Add prometheus endpoint for getting metrics (#33)

config.yml.sample

@@ -9,6 +9,9 @@ service:
   frontendurl: ""
   # The number of items which gets returned per page
   pagecount: 50
+  # If set to true, enables a /metrics endpoint for prometheus to collect metrics about the system
+  # You'll need to use redis for this in order to enable common metrics over multiple nodes
+  enablemetrics: true
 
 database:
   # Database type to use. Supported types are mysql and sqlite.
@@ -25,18 +28,26 @@ database:
   Path: "./vikunja.db"
   # Whether to show mysql queries or not. Useful for debugging.
   showqueries: "false"
+  # Sets the max open connections to the database. Only used when using mysql.
+  openconnections: 100
+
+redis:
+  # Whether to enable redis or not
+  enabled: false
+  # The host of the redis server including its port.
+  redishost: 'localhost:6379'
+  # The password used to authenicate against the redis server
+  redispassword: ''
+  # 0 means default database
+  db: 0
 
 cache:
   # If cache is enabled or not
   enabled: false
-  # Cache type. Possible values are memory or redis
+  # Cache type. Possible values are memory or redis, you'll need to enable redis below when using redis
   type: memory
   # When using memory this defines the maximum size an element can take
   maxelementsize: 1000
-  # When using redis, this is the host of the redis server including its port.
-  redishost: 'localhost:6379'
-  # When using redis, this is the password used to authenicate against the redis server
-  redispassword: ''
 
 mailer:
   # SMTP Host

docs/config.md

@@ -35,6 +35,9 @@ service:
   rootpath: <the path of the executable>
   # The number of items which gets returned per page
   pagecount: 50
+  # If set to true, enables a /metrics endpoint for prometheus to collect metrics about the system
+  # You'll need to use redis for this in order to enable common metrics over multiple nodes
+  enablemetrics: false
 
 database:
   # Database type to use. Supported types are mysql and sqlite.
@@ -54,18 +57,23 @@ database:
   # Sets the max open connections to the database. Only used when using mysql.
   openconnections: 100
 
-
 cache:
   # If cache is enabled or not
   enabled: false
-  # Cache type. Possible values are memory or redis
+  # Cache type. Possible values are memory or redis, you'll need to enable redis below when using redis
   type: memory
   # When using memory this defines the maximum size an element can take
   maxelementsize: 1000
-  # When using redis, this is the host of the redis server including its port.
+
+redis:
+  # Whether to enable redis or not
+  enabled: false
+  # The host of the redis server including its port.
   redishost: 'localhost:6379'
-  # When using redis, this is the password used to authenicate against the redis server
+  # The password used to authenicate against the redis server
   redispassword: ''
+  # 0 means default database
+  db: 0
 
 mailer:
   # SMTP Host

go.mod

@@ -30,6 +30,7 @@ require (
 	github.com/ghodss/yaml v1.0.0 // indirect
 	github.com/go-openapi/spec v0.17.2 // indirect
 	github.com/go-openapi/swag v0.17.2 // indirect
+	github.com/go-redis/redis v6.14.2+incompatible
 	github.com/go-sql-driver/mysql v0.0.0-20171007150158-ee359f95877b
 	github.com/go-xorm/builder v0.0.0-20170519032130-c8871c857d25 // indirect
 	github.com/go-xorm/core v0.5.8
@@ -49,6 +50,7 @@ require (
 	github.com/mitchellh/mapstructure v1.1.2 // indirect
 	github.com/op/go-logging v0.0.0-20160315200505-970db520ece7
 	github.com/pkg/errors v0.8.0 // indirect
+	github.com/prometheus/client_golang v0.9.2
 	github.com/spf13/viper v1.2.0
 	github.com/stretchr/testify v1.2.2
 	github.com/swaggo/echo-swagger v0.0.0-20180315045949-97f46bb9e5a5

go.sum

@@ -14,6 +14,8 @@ github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc h1:cAKDfWh5Vpd
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/asaskevich/govalidator v0.0.0-20180720115003-f9ffefc3facf h1:eg0MeVzsP1G42dRafH3vf+al2vQIJU0YHX+1Tw87oco=
 github.com/asaskevich/govalidator v0.0.0-20180720115003-f9ffefc3facf/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
+github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973 h1:xJ4a3vCFaGF/jqvzLMYoU8P317H5OQ+Via4RmuPwCS0=
+github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/client9/misspell v0.3.4 h1:ta993UF76GwbvJcIo3Y68y/M3WxlpEHPWIGDkJYwzJI=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -39,6 +41,8 @@ github.com/go-openapi/spec v0.17.2/go.mod h1:XkF/MOi14NmjsfZ8VtAKf8pIlbZzyoTvZsd
 github.com/go-openapi/swag v0.17.0/go.mod h1:AByQ+nYG6gQg71GINrmuDXCPWdL640yX49/kXLo40Tg=
 github.com/go-openapi/swag v0.17.2 h1:K/ycE/XTUDFltNHSO32cGRUhrVGJD64o8WgAIZNyc3k=
 github.com/go-openapi/swag v0.17.2/go.mod h1:AByQ+nYG6gQg71GINrmuDXCPWdL640yX49/kXLo40Tg=
+github.com/go-redis/redis v6.14.2+incompatible h1:UE9pLhzmWf+xHNmZsoccjXosPicuiNaInPgym8nzfg0=
+github.com/go-redis/redis v6.14.2+incompatible/go.mod h1:NAIEuMOZ/fxfXJIrKDQDz8wamY7mA7PouImQ2Jvg6kA=
 github.com/go-sql-driver/mysql v0.0.0-20171007150158-ee359f95877b h1:/CMGgAYard7jx9+bI7tUIqafFDR7Pv2BRu2Tb5dDaqM=
 github.com/go-sql-driver/mysql v0.0.0-20171007150158-ee359f95877b/go.mod h1:zAC/RDZ24gD3HViQzih4MyKcchzm+sOG5ZlKdlhCg5w=
 github.com/go-xorm/builder v0.0.0-20170519032130-c8871c857d25 h1:jUX9yw6+iKrs/WuysV2M6ap/ObK/07SE/a7I2uxitwM=
@@ -51,6 +55,8 @@ github.com/go-xorm/xorm v0.0.0-20170930012613-29d4a0330a00 h1:jlA1XEj8QHl6my6FUk
 github.com/go-xorm/xorm v0.0.0-20170930012613-29d4a0330a00/go.mod h1:i7qRPD38xj/v75UV+a9pEzr5tfRaH2ndJfwt/fGbQhs=
 github.com/go-xorm/xorm-redis-cache v0.0.0-20180727005610-859b313566b2 h1:57QbyUkFcFjipHJQstYR5owRxsQzgD8/OAO/hr4yl/E=
 github.com/go-xorm/xorm-redis-cache v0.0.0-20180727005610-859b313566b2/go.mod h1:xxK9FGkFXrau9/vGdDYSOyQfSgKXBV7iHXpQfNuv6B0=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/gordonklaus/ineffassign v0.0.0-20180909121442-1003c8bd00dc h1:cJlkeAx1QYgO5N80aF5xRGstVsRQwgLR7uA2FnP1ZjY=
@@ -84,6 +90,8 @@ github.com/mattn/go-oci8 v0.0.0-20181011085415-1a014d1384b5 h1:+IPgoz43mdEYG5lrq
 github.com/mattn/go-oci8 v0.0.0-20181011085415-1a014d1384b5/go.mod h1:/M9VLO+lUPmxvoOK2PfWRZ8mTtB4q1Hy9lEGijv9Nr8=
 github.com/mattn/go-sqlite3 v1.9.0 h1:pDRiWfl+++eC2FEFRy6jXmQlvp4Yh3z1MJKg4UeYM/4=
 github.com/mattn/go-sqlite3 v1.9.0/go.mod h1:FPy6KqzDD04eiIsT53CuJW3U88zkxoIYsOqkbpncsNc=
+github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
+github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/mitchellh/mapstructure v1.0.0 h1:vVpGvMXJPqSDh2VYHF7gsfQj8Ncx+Xw5Y1KHeTRY+7I=
 github.com/mitchellh/mapstructure v1.0.0/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
@@ -96,6 +104,14 @@ github.com/pkg/errors v0.8.0 h1:WdK/asTD0HN+q6hsWO3/vpuAkAr+tw6aNJNDFFf0+qw=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/prometheus/client_golang v0.9.2 h1:awm861/B8OKDd2I/6o1dy3ra4BamzKhYOiGItCeZ740=
+github.com/prometheus/client_golang v0.9.2/go.mod h1:OsXs2jCmiKlQ1lTBmv21f2mNfw4xf/QclQDMrYNZzcM=
+github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910 h1:idejC8f05m9MGOsuEi1ATq9shN03HrxNkD/luQvxCv8=
+github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
+github.com/prometheus/common v0.0.0-20181126121408-4724e9255275 h1:PnBWHBf+6L0jOqq0gIVUe6Yk0/QMZ640k6NvkxcBf+8=
+github.com/prometheus/common v0.0.0-20181126121408-4724e9255275/go.mod h1:daVV7qP5qjZbuso7PdcryaAu0sAZbrN9i7WWcTMWvro=
+github.com/prometheus/procfs v0.0.0-20181204211112-1dc9a6cbc91a h1:9a8MnZMP0X2nLJdBg+pBmGgkJlSaKC2KaQmTCk1XDtE=
+github.com/prometheus/procfs v0.0.0-20181204211112-1dc9a6cbc91a/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/spf13/afero v1.1.2 h1:m8/z1t7/fwjysjQRYbP0RD+bUIF/8tJwPdEZsI83ACI=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/cast v1.2.0 h1:HHl1DSRbEQN2i8tJmtS6ViPyHx35+p51amrdsiTCrkg=
@@ -133,6 +149,9 @@ golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3 h1:x/bBzNauLQAlE3fLku/xy92Y
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/net v0.0.0-20181005035420-146acd28ed58 h1:otZG8yDCO4LVps5+9bxOeNiCvgmOyt96J3roHTYs7oE=
 golang.org/x/net v0.0.0-20181005035420-146acd28ed58/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20181201002055-351d144fa1fc h1:a3CU5tJYVj92DY2LaA1kUkrsqD5/3mLDhx2NcNqyW+0=
+golang.org/x/net v0.0.0-20181201002055-351d144fa1fc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180906133057-8cf3aee42992 h1:BH3eQWeGbwRU2+wxxuuPOdFBmaiBH81O8BugSjHeTFg=
 golang.org/x/sys v0.0.0-20180906133057-8cf3aee42992/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181107165924-66b7b1311ac8/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

main.go

@@ -18,12 +18,11 @@ package main
 
 import (
 	"code.vikunja.io/api/docs"
-	"code.vikunja.io/api/pkg/config"
+	_ "code.vikunja.io/api/pkg/config" // To trigger its init() which initializes the config
 	"code.vikunja.io/api/pkg/log"
 	"code.vikunja.io/api/pkg/mail"
 	"code.vikunja.io/api/pkg/models"
 	"code.vikunja.io/api/pkg/routes"
-
 	"context"
 	"github.com/spf13/viper"
 	"os"
@@ -39,18 +38,10 @@ func main() {
 	// Init logging
 	log.InitLogger()
 
-	// Init Config
-	err := config.InitConfig()
-	if err != nil {
-		log.Log.Error(err.Error())
-		os.Exit(1)
-	}
-
 	// Set Engine
-	err = models.SetEngine()
+	err := models.SetEngine()
 	if err != nil {
-		log.Log.Error(err.Error())
+		log.Log.Fatal(err.Error())
-		os.Exit(1)
 	}
 
 	// Start the mail daemon

pkg/config/config.go

@@ -17,6 +17,7 @@
 package config
 
 import (
+	"code.vikunja.io/api/pkg/log"
 	"crypto/rand"
 	"fmt"
 	"github.com/spf13/viper"
@@ -26,13 +27,13 @@ import (
 )
 
 // InitConfig initializes the config, sets defaults etc.
-func InitConfig() (err error) {
+func init() {
 
 	// Set defaults
 	// Service config
 	random, err := random(32)
 	if err != nil {
-		return err
+		log.Log.Fatal(err.Error())
 	}
 
 	// Service
@@ -46,6 +47,7 @@ func InitConfig() (err error) {
 	exPath := filepath.Dir(ex)
 	viper.SetDefault("service.rootpath", exPath)
 	viper.SetDefault("service.pagecount", 50)
+	viper.SetDefault("service.enablemetrics", false)
 	// Database
 	viper.SetDefault("database.type", "sqlite")
 	viper.SetDefault("database.host", "localhost")
@@ -59,8 +61,6 @@ func InitConfig() (err error) {
 	viper.SetDefault("cache.enabled", false)
 	viper.SetDefault("cache.type", "memory")
 	viper.SetDefault("cache.maxelementsize", 1000)
-	viper.SetDefault("cache.redishost", "localhost:6379")
-	viper.SetDefault("cache.redispassword", "")
 	// Mailer
 	viper.SetDefault("mailer.host", "")
 	viper.SetDefault("mailer.port", "587")
@@ -70,6 +70,11 @@ func InitConfig() (err error) {
 	viper.SetDefault("mailer.fromemail", "mail@vikunja")
 	viper.SetDefault("mailer.queuelength", 100)
 	viper.SetDefault("mailer.queuetimeout", 30)
+	// Redis
+	viper.SetDefault("redis.enabled", false)
+	viper.SetDefault("redis.host", "localhost:6379")
+	viper.SetDefault("redis.password", "")
+	viper.SetDefault("redis.db", 0)
 
 	// Init checking for environment variables
 	viper.SetEnvPrefix("vikunja")
@@ -81,11 +86,9 @@ func InitConfig() (err error) {
 	viper.SetConfigName("config")
 	err = viper.ReadInConfig()
 	if err != nil {
-		fmt.Println(err)
+		log.Log.Info(err)
-		fmt.Println("Using defaults.")
+		log.Log.Info("Using defaults.")
 	}
-
-	return nil
 }
 
 func random(length int) (string, error) {

pkg/metrics/active_users.go

@@ -0,0 +1,92 @@
+//  Vikunja is a todo-list application to facilitate your life.
+//  Copyright 2018 Vikunja and contributors. All rights reserved.
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package metrics
+
+import (
+	"bytes"
+	"code.vikunja.io/api/pkg/log"
+	"encoding/gob"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+	"time"
+)
+
+// SecondsUntilInactive defines the seconds until a user is considered inactive
+const SecondsUntilInactive = 60
+
+// ActiveUsersKey is the key used to store active users in redis
+const ActiveUsersKey = `activeusers`
+
+// ActiveUser defines an active user
+type ActiveUser struct {
+	UserID   int64
+	LastSeen time.Time
+}
+
+func init() {
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_active_users",
+		Help: "The currently active users on this node",
+	}, func() float64 {
+
+		allActiveUsers, err := GetActiveUsers()
+		if err != nil {
+			log.Log.Error(err.Error())
+		}
+		activeUsersCount := 0
+		for _, u := range allActiveUsers {
+			if time.Since(u.LastSeen) < SecondsUntilInactive*time.Second {
+				activeUsersCount++
+			}
+		}
+		return float64(activeUsersCount)
+	})
+}
+
+// GetActiveUsers returns the active users from redis
+func GetActiveUsers() (users []*ActiveUser, err error) {
+
+	activeUsersR, err := r.Get(ActiveUsersKey).Bytes()
+	if err != nil {
+		if err.Error() == "redis: nil" {
+			return users, nil
+		}
+		return
+	}
+
+	var b bytes.Buffer
+	_, err = b.Write(activeUsersR)
+	if err != nil {
+		return nil, err
+	}
+	d := gob.NewDecoder(&b)
+	if err := d.Decode(&users); err != nil {
+		return nil, err
+	}
+	return
+}
+
+// SetActiveUsers sets the active users from redis
+func SetActiveUsers(users []*ActiveUser) (err error) {
+	var b bytes.Buffer
+	e := gob.NewEncoder(&b)
+	if err := e.Encode(users); err != nil {
+		return err
+	}
+
+	return r.Set(ActiveUsersKey, b.Bytes(), 0).Err()
+}

pkg/metrics/metrics.go

@@ -0,0 +1,123 @@
+//  Vikunja is a todo-list application to facilitate your life.
+//  Copyright 2018 Vikunja and contributors. All rights reserved.
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package metrics
+
+import (
+	"code.vikunja.io/api/pkg/log"
+	"code.vikunja.io/api/pkg/red"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+	"github.com/spf13/viper"
+)
+
+var r = red.GetRedis()
+
+const (
+	// ListCountKey is the name of the key in which we save the list count
+	ListCountKey = `listcount`
+
+	// UserCountKey is the name of the key we use to store total users in redis
+	UserCountKey = `usercount`
+
+	// NamespaceCountKey is the name of the key we use to store the amount of total namespaces in redis
+	NamespaceCountKey = `namespacecount`
+
+	// TaskCountKey is the name of the key we use to store the amount of total tasks in redis
+	TaskCountKey = `taskcount`
+
+	// TeamCountKey is the name of the key we use to store the amount of total teams in redis
+	TeamCountKey = `teamcount`
+)
+
+func init() {
+	// Register total list count metric
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_list_count",
+		Help: "The number of lists on this instance",
+	}, func() float64 {
+		count, _ := GetCount(ListCountKey)
+		return float64(count)
+	})
+
+	// Register total user count metric
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_user_count",
+		Help: "The total number of users on this instance",
+	}, func() float64 {
+		count, _ := GetCount(UserCountKey)
+		return float64(count)
+	})
+
+	// Register total Namespaces count metric
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_namespcae_count",
+		Help: "The total number of namespaces on this instance",
+	}, func() float64 {
+		count, _ := GetCount(NamespaceCountKey)
+		return float64(count)
+	})
+
+	// Register total Tasks count metric
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_task_count",
+		Help: "The total number of tasks on this instance",
+	}, func() float64 {
+		count, _ := GetCount(TaskCountKey)
+		return float64(count)
+	})
+
+	// Register total user count metric
+	promauto.NewGaugeFunc(prometheus.GaugeOpts{
+		Name: "vikunja_team_count",
+		Help: "The total number of teams on this instance",
+	}, func() float64 {
+		count, _ := GetCount(TeamCountKey)
+		return float64(count)
+	})
+}
+
+// GetCount returns the current count from redis
+func GetCount(key string) (count int64, err error) {
+	count, err = r.Get(key).Int64()
+	if err != nil && err.Error() != "redis: nil" {
+		return
+	}
+	err = nil
+
+	return
+}
+
+// SetCount sets the list count to a given value
+func SetCount(count int64, key string) error {
+	return r.Set(key, count, 0).Err()
+}
+
+// UpdateCount updates a count with a given amount
+func UpdateCount(update int64, key string) {
+	if !viper.GetBool("service.enablemetrics") {
+		return
+	}
+	oldtotal, err := GetCount(key)
+	if err != nil {
+		log.Log.Error(err.Error())
+	}
+
+	err = SetCount(oldtotal+update, key)
+	if err != nil {
+		log.Log.Error(err.Error())
+	}
+}

pkg/models/list_create_update.go

@@ -16,7 +16,10 @@
 
 package models
 
-import "code.vikunja.io/web"
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	"code.vikunja.io/web"
+)
 
 // CreateOrUpdateList updates a list or creates it if it doesn't exist
 func CreateOrUpdateList(list *List) (err error) {
@@ -36,6 +39,7 @@ func CreateOrUpdateList(list *List) (err error) {
 
 	if list.ID == 0 {
 		_, err = x.Insert(list)
+		metrics.UpdateCount(1, metrics.ListCountKey)
 	} else {
 		_, err = x.ID(list.ID).Update(list)
 	}

pkg/models/list_delete.go

@@ -16,7 +16,10 @@
 
 package models
 
-import _ "code.vikunja.io/web" // For swaggerdocs generation
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	_ "code.vikunja.io/web" // For swaggerdocs generation
+)
 
 // Delete implements the delete method of CRUDable
 // @Summary Deletes a list
@@ -41,6 +44,7 @@ func (l *List) Delete() (err error) {
 	if err != nil {
 		return
 	}
+	metrics.UpdateCount(-1, metrics.ListCountKey)
 
 	// Delete all todotasks on that list
 	_, err = x.Where("list_id = ?", l.ID).Delete(&ListTask{})

pkg/models/list_tasks_create_update.go

@@ -17,6 +17,7 @@
 package models
 
 import (
+	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/web"
 	"github.com/imdario/mergo"
 )
@@ -61,8 +62,12 @@ func (i *ListTask) Create(a web.Auth) (err error) {
 
 	i.CreatedByID = u.ID
 	i.CreatedBy = u
-	_, err = x.Insert(i)
+	if _, err = x.Insert(i); err != nil {
-	return err
+		return err
+	}
+
+	metrics.UpdateCount(1, metrics.TaskCountKey)
+	return
 }
 
 // Update updates a list task

pkg/models/list_tasks_delete.go

@@ -16,7 +16,10 @@
 
 package models
 
-import _ "code.vikunja.io/web" // For swaggerdocs generation
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	_ "code.vikunja.io/web" // For swaggerdocs generation
+)
 
 // Delete implements the delete method for listTask
 // @Summary Delete a task
@@ -38,6 +41,10 @@ func (i *ListTask) Delete() (err error) {
 		return
 	}
 
-	_, err = x.ID(i.ID).Delete(ListTask{})
+	if _, err = x.ID(i.ID).Delete(ListTask{}); err != nil {
+		return err
+	}
+
+	metrics.UpdateCount(-1, metrics.TaskCountKey)
 	return
 }

pkg/models/models.go

@@ -17,14 +17,13 @@
 package models
 
 import (
+	"encoding/gob"
 	"fmt"
 	_ "github.com/go-sql-driver/mysql" // Because.
 	"github.com/go-xorm/core"
 	"github.com/go-xorm/xorm"
 	xrc "github.com/go-xorm/xorm-redis-cache"
 	_ "github.com/mattn/go-sqlite3" // Because.
-
-	"encoding/gob"
 	"github.com/spf13/viper"
 )
 
@@ -86,7 +85,7 @@ func SetEngine() (err error) {
 			x.SetDefaultCacher(cacher)
 			break
 		case "redis":
-			cacher := xrc.NewRedisCacher(viper.GetString("cache.redishost"), viper.GetString("cache.redispassword"), xrc.DEFAULT_EXPIRATION, x.Logger())
+			cacher := xrc.NewRedisCacher(viper.GetString("redis.host"), viper.GetString("redis.password"), xrc.DEFAULT_EXPIRATION, x.Logger())
 			x.SetDefaultCacher(cacher)
 			gob.Register(tables)
 			break
@@ -118,3 +117,8 @@ func getLimitFromPageIndex(page int) (limit, start int) {
 	start = limit * (page - 1)
 	return
 }
+
+// GetTotalCount returns the total amount of something
+func GetTotalCount(counting interface{}) (count int64, err error) {
+	return x.Count(counting)
+}

pkg/models/namespace_create.go

@@ -16,7 +16,10 @@
 
 package models
 
-import "code.vikunja.io/web"
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	"code.vikunja.io/web"
+)
 
 // Create implements the creation method via the interface
 // @Summary Creates a new namespace
@@ -51,6 +54,10 @@ func (n *Namespace) Create(a web.Auth) (err error) {
 	n.OwnerID = n.Owner.ID
 
 	// Insert
-	_, err = x.Insert(n)
+	if _, err = x.Insert(n); err != nil {
+		return err
+	}
+
+	metrics.UpdateCount(1, metrics.NamespaceCountKey)
 	return
 }

pkg/models/namespace_delete.go

@@ -16,7 +16,10 @@
 
 package models
 
-import _ "code.vikunja.io/web" // For swaggerdocs generation
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	_ "code.vikunja.io/web" // For swaggerdocs generation
+)
 
 // Delete deletes a namespace
 // @Summary Deletes a namespace
@@ -66,5 +69,7 @@ func (n *Namespace) Delete() (err error) {
 		return
 	}
 
+	metrics.UpdateCount(-1, metrics.NamespaceCountKey)
+
 	return
 }

pkg/models/teams_create.go

@@ -16,7 +16,10 @@
 
 package models
 
-import "code.vikunja.io/web"
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	"code.vikunja.io/web"
+)
 
 // Create is the handler to create a team
 // @Summary Creates a new team
@@ -51,6 +54,10 @@ func (t *Team) Create(a web.Auth) (err error) {
 
 	// Insert the current user as member and admin
 	tm := TeamMember{TeamID: t.ID, UserID: doer.ID, Admin: true}
-	err = tm.Create(doer)
+	if err = tm.Create(doer); err != nil {
+		return err
+	}
+
+	metrics.UpdateCount(1, metrics.TeamCountKey)
 	return
 }

pkg/models/teams_delete.go

@@ -16,7 +16,10 @@
 
 package models
 
-import _ "code.vikunja.io/web" // For swaggerdocs generation
+import (
+	"code.vikunja.io/api/pkg/metrics"
+	_ "code.vikunja.io/web" // For swaggerdocs generation
+)
 
 // Delete deletes a team
 // @Summary Deletes a team
@@ -57,5 +60,10 @@ func (t *Team) Delete() (err error) {
 
 	// Delete team <-> lists relations
 	_, err = x.Where("team_id = ?", t.ID).Delete(&TeamList{})
+	if err != nil {
+		return
+	}
+
+	metrics.UpdateCount(-1, metrics.TeamCountKey)
 	return
 }

pkg/models/unit_tests.go

@@ -17,6 +17,8 @@
 package models
 
 import (
+	_ "code.vikunja.io/api/pkg/config" // To trigger its init() which initializes the config
+	"code.vikunja.io/api/pkg/log"
 	"code.vikunja.io/api/pkg/mail"
 	"fmt"
 	"github.com/go-xorm/core"
@@ -36,8 +38,7 @@ func MainTest(m *testing.M, pathToRoot string) {
 	var err error
 	fixturesDir := filepath.Join(pathToRoot, "models", "fixtures")
 	if err = createTestEngine(fixturesDir); err != nil {
-		fmt.Fprintf(os.Stderr, "Error creating test engine: %v\n", err)
+		log.Log.Fatalf("Error creating test engine: %v\n", err)
-		os.Exit(1)
 	}
 
 	IsTesting = true
@@ -46,7 +47,9 @@ func MainTest(m *testing.M, pathToRoot string) {
 	mail.StartMailDaemon()
 
 	// Create test database
-	PrepareTestDatabase()
+	if err = PrepareTestDatabase(); err != nil {
+		log.Log.Fatal(err.Error())
+	}
 
 	os.Exit(m.Run())
 }

pkg/models/user.go

@@ -18,12 +18,14 @@ package models
 
 import (
 	"code.vikunja.io/api/pkg/log"
+	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/web"
 	"fmt"
 	"github.com/dgrijalva/jwt-go"
 	"github.com/labstack/echo"
 	"golang.org/x/crypto/bcrypt"
 	"reflect"
+	"time"
 )
 
 // UserLogin Object to recive user credentials in JSON format
@@ -159,3 +161,30 @@ func GetCurrentUser(c echo.Context) (user *User, err error) {
 
 	return
 }
+
+// UpdateActiveUsersFromContext updates the currently active users in redis
+func UpdateActiveUsersFromContext(c echo.Context) (err error) {
+	user, err := GetCurrentUser(c)
+	if err != nil {
+		return err
+	}
+
+	allActiveUsers, err := metrics.GetActiveUsers()
+	if err != nil {
+		return
+	}
+
+	var uupdated bool
+	for in, u := range allActiveUsers {
+		if u.UserID == user.ID {
+			allActiveUsers[in].LastSeen = time.Now()
+			uupdated = true
+		}
+	}
+
+	if !uupdated {
+		allActiveUsers = append(allActiveUsers, &metrics.ActiveUser{UserID: user.ID, LastSeen: time.Now()})
+	}
+
+	return metrics.SetActiveUsers(allActiveUsers)
+}

pkg/models/user_add_update.go

@@ -18,6 +18,7 @@ package models
 
 import (
 	"code.vikunja.io/api/pkg/mail"
+	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/api/pkg/utils"
 	"golang.org/x/crypto/bcrypt"
 )
@@ -78,6 +79,9 @@ func CreateUser(user User) (newUser User, err error) {
 		return User{}, err
 	}
 
+	// Update the metrics
+	metrics.UpdateCount(1, metrics.ActiveUsersKey)
+
 	// Get the  full new User
 	newUserOut, err := GetUser(newUser)
 	if err != nil {

pkg/models/user_delete.go

@@ -16,6 +16,8 @@
 
 package models
 
+import "code.vikunja.io/api/pkg/metrics"
+
 // DeleteUserByID deletes a user by its ID
 func DeleteUserByID(id int64, doer *User) error {
 	// Check if the id is 0
@@ -30,5 +32,8 @@ func DeleteUserByID(id int64, doer *User) error {
 		return err
 	}
 
+	// Update the metrics
+	metrics.UpdateCount(-1, metrics.ActiveUsersKey)
+
 	return err
 }

pkg/red/redis.go

@@ -0,0 +1,52 @@
+//  Vikunja is a todo-list application to facilitate your life.
+//  Copyright 2018 Vikunja and contributors. All rights reserved.
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package red
+
+import (
+	"code.vikunja.io/api/pkg/log"
+	"github.com/go-redis/redis"
+	"github.com/spf13/viper"
+)
+
+var r *redis.Client
+
+// SetRedis initializes a redis connection
+func init() {
+	if !viper.GetBool("redis.enabled") {
+		return
+	}
+
+	if viper.GetString("redis.host") == "" {
+		log.Log.Fatal("No redis host provided.")
+	}
+
+	r = redis.NewClient(&redis.Options{
+		Addr:     viper.GetString("redis.host"),
+		Password: viper.GetString("redis.password"),
+		DB:       viper.GetInt("redis.db"),
+	})
+
+	err := r.Ping().Err()
+	if err != nil {
+		log.Log.Fatal(err.Error())
+	}
+}
+
+// GetRedis returns a pointer to a redis client
+func GetRedis() *redis.Client {
+	return r
+}

pkg/routes/routes.go

@@ -45,6 +45,7 @@ package routes
 import (
 	_ "code.vikunja.io/api/docs" // To generate swagger docs
 	"code.vikunja.io/api/pkg/log"
+	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/api/pkg/models"
 	apiv1 "code.vikunja.io/api/pkg/routes/api/v1"
 	"code.vikunja.io/web"
@@ -52,6 +53,7 @@ import (
 	"github.com/asaskevich/govalidator"
 	"github.com/labstack/echo"
 	"github.com/labstack/echo/middleware"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/spf13/viper"
 	"github.com/swaggo/echo-swagger"
 )
@@ -112,6 +114,54 @@ func RegisterRoutes(e *echo.Echo) {
 	// Swagger UI
 	a.GET("/swagger/*", echoSwagger.WrapHandler)
 
+	// Prometheus endpoint
+	if viper.GetBool("service.enablemetrics") {
+
+		if !viper.GetBool("redis.enabled") {
+			log.Log.Fatal("You have to enable redis in order to use metrics")
+		}
+
+		type countable struct {
+			Rediskey string
+			Type     interface{}
+		}
+
+		for _, c := range []countable{
+			{
+				metrics.ListCountKey,
+				models.List{},
+			},
+			{
+				metrics.UserCountKey,
+				models.User{},
+			},
+			{
+				metrics.NamespaceCountKey,
+				models.Namespace{},
+			},
+			{
+				metrics.TaskCountKey,
+				models.ListTask{},
+			},
+			{
+				metrics.TeamCountKey,
+				models.Team{},
+			},
+		} {
+			// Set initial totals
+			total, err := models.GetTotalCount(c.Type)
+			if err != nil {
+				log.Log.Fatalf("Could not set initial count for %v, error was %s", c.Type, err)
+			}
+			if err := metrics.SetCount(total, c.Rediskey); err != nil {
+				log.Log.Fatalf("Could not set initial count for %v, error was %s", c.Type, err)
+			}
+		}
+
+		a.GET("/metrics", echo.WrapHandler(promhttp.Handler()))
+	}
+
+	// User stuff
 	a.POST("/login", apiv1.Login)
 	a.POST("/register", apiv1.RegisterUser)
 	a.POST("/user/password/token", apiv1.UserRequestResetPasswordToken)
@@ -138,6 +188,21 @@ func RegisterRoutes(e *echo.Echo) {
 		}
 	})
 
+	// Middleware to collect metrics
+	if viper.GetBool("service.enablemetrics") {
+		a.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
+			return func(c echo.Context) error {
+
+				// Update currently active users
+				if err := models.UpdateActiveUsersFromContext(c); err != nil {
+					log.Log.Error(err)
+					return next(c)
+				}
+				return next(c)
+			}
+		})
+	}
+
 	a.POST("/tokenTest", apiv1.CheckToken)
 
 	// User stuff

vendor/github.com/beorn7/perks/LICENSE

@@ -0,0 +1,20 @@
+Copyright (C) 2013 Blake Mizerany
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/beorn7/perks/quantile/stream.go

@@ -0,0 +1,316 @@
+// Package quantile computes approximate quantiles over an unbounded data
+// stream within low memory and CPU bounds.
+//
+// A small amount of accuracy is traded to achieve the above properties.
+//
+// Multiple streams can be merged before calling Query to generate a single set
+// of results. This is meaningful when the streams represent the same type of
+// data. See Merge and Samples.
+//
+// For more detailed information about the algorithm used, see:
+//
+// Effective Computation of Biased Quantiles over Data Streams
+//
+// http://www.cs.rutgers.edu/~muthu/bquant.pdf
+package quantile
+
+import (
+	"math"
+	"sort"
+)
+
+// Sample holds an observed value and meta information for compression. JSON
+// tags have been added for convenience.
+type Sample struct {
+	Value float64 `json:",string"`
+	Width float64 `json:",string"`
+	Delta float64 `json:",string"`
+}
+
+// Samples represents a slice of samples. It implements sort.Interface.
+type Samples []Sample
+
+func (a Samples) Len() int           { return len(a) }
+func (a Samples) Less(i, j int) bool { return a[i].Value < a[j].Value }
+func (a Samples) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+type invariant func(s *stream, r float64) float64
+
+// NewLowBiased returns an initialized Stream for low-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the lower ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within (1±Epsilon)*Quantile.
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewLowBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * r
+	}
+	return newStream(ƒ)
+}
+
+// NewHighBiased returns an initialized Stream for high-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the higher ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within 1-(1±Epsilon)*(1-Quantile).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewHighBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * (s.n - r)
+	}
+	return newStream(ƒ)
+}
+
+// NewTargeted returns an initialized Stream concerned with a particular set of
+// quantile values that are supplied a priori. Knowing these a priori reduces
+// space and computation time. The targets map maps the desired quantiles to
+// their absolute errors, i.e. the true quantile of a value returned by a query
+// is guaranteed to be within (Quantile±Epsilon).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error properties.
+func NewTargeted(targetMap map[float64]float64) *Stream {
+	// Convert map to slice to avoid slow iterations on a map.
+	// ƒ is called on the hot path, so converting the map to a slice
+	// beforehand results in significant CPU savings.
+	targets := targetMapToSlice(targetMap)
+
+	ƒ := func(s *stream, r float64) float64 {
+		var m = math.MaxFloat64
+		var f float64
+		for _, t := range targets {
+			if t.quantile*s.n <= r {
+				f = (2 * t.epsilon * r) / t.quantile
+			} else {
+				f = (2 * t.epsilon * (s.n - r)) / (1 - t.quantile)
+			}
+			if f < m {
+				m = f
+			}
+		}
+		return m
+	}
+	return newStream(ƒ)
+}
+
+type target struct {
+	quantile float64
+	epsilon  float64
+}
+
+func targetMapToSlice(targetMap map[float64]float64) []target {
+	targets := make([]target, 0, len(targetMap))
+
+	for quantile, epsilon := range targetMap {
+		t := target{
+			quantile: quantile,
+			epsilon:  epsilon,
+		}
+		targets = append(targets, t)
+	}
+
+	return targets
+}
+
+// Stream computes quantiles for a stream of float64s. It is not thread-safe by
+// design. Take care when using across multiple goroutines.
+type Stream struct {
+	*stream
+	b      Samples
+	sorted bool
+}
+
+func newStream(ƒ invariant) *Stream {
+	x := &stream{ƒ: ƒ}
+	return &Stream{x, make(Samples, 0, 500), true}
+}
+
+// Insert inserts v into the stream.
+func (s *Stream) Insert(v float64) {
+	s.insert(Sample{Value: v, Width: 1})
+}
+
+func (s *Stream) insert(sample Sample) {
+	s.b = append(s.b, sample)
+	s.sorted = false
+	if len(s.b) == cap(s.b) {
+		s.flush()
+	}
+}
+
+// Query returns the computed qth percentiles value. If s was created with
+// NewTargeted, and q is not in the set of quantiles provided a priori, Query
+// will return an unspecified result.
+func (s *Stream) Query(q float64) float64 {
+	if !s.flushed() {
+		// Fast path when there hasn't been enough data for a flush;
+		// this also yields better accuracy for small sets of data.
+		l := len(s.b)
+		if l == 0 {
+			return 0
+		}
+		i := int(math.Ceil(float64(l) * q))
+		if i > 0 {
+			i -= 1
+		}
+		s.maybeSort()
+		return s.b[i].Value
+	}
+	s.flush()
+	return s.stream.query(q)
+}
+
+// Merge merges samples into the underlying streams samples. This is handy when
+// merging multiple streams from separate threads, database shards, etc.
+//
+// ATTENTION: This method is broken and does not yield correct results. The
+// underlying algorithm is not capable of merging streams correctly.
+func (s *Stream) Merge(samples Samples) {
+	sort.Sort(samples)
+	s.stream.merge(samples)
+}
+
+// Reset reinitializes and clears the list reusing the samples buffer memory.
+func (s *Stream) Reset() {
+	s.stream.reset()
+	s.b = s.b[:0]
+}
+
+// Samples returns stream samples held by s.
+func (s *Stream) Samples() Samples {
+	if !s.flushed() {
+		return s.b
+	}
+	s.flush()
+	return s.stream.samples()
+}
+
+// Count returns the total number of samples observed in the stream
+// since initialization.
+func (s *Stream) Count() int {
+	return len(s.b) + s.stream.count()
+}
+
+func (s *Stream) flush() {
+	s.maybeSort()
+	s.stream.merge(s.b)
+	s.b = s.b[:0]
+}
+
+func (s *Stream) maybeSort() {
+	if !s.sorted {
+		s.sorted = true
+		sort.Sort(s.b)
+	}
+}
+
+func (s *Stream) flushed() bool {
+	return len(s.stream.l) > 0
+}
+
+type stream struct {
+	n float64
+	l []Sample
+	ƒ invariant
+}
+
+func (s *stream) reset() {
+	s.l = s.l[:0]
+	s.n = 0
+}
+
+func (s *stream) insert(v float64) {
+	s.merge(Samples{{v, 1, 0}})
+}
+
+func (s *stream) merge(samples Samples) {
+	// TODO(beorn7): This tries to merge not only individual samples, but
+	// whole summaries. The paper doesn't mention merging summaries at
+	// all. Unittests show that the merging is inaccurate. Find out how to
+	// do merges properly.
+	var r float64
+	i := 0
+	for _, sample := range samples {
+		for ; i < len(s.l); i++ {
+			c := s.l[i]
+			if c.Value > sample.Value {
+				// Insert at position i.
+				s.l = append(s.l, Sample{})
+				copy(s.l[i+1:], s.l[i:])
+				s.l[i] = Sample{
+					sample.Value,
+					sample.Width,
+					math.Max(sample.Delta, math.Floor(s.ƒ(s, r))-1),
+					// TODO(beorn7): How to calculate delta correctly?
+				}
+				i++
+				goto inserted
+			}
+			r += c.Width
+		}
+		s.l = append(s.l, Sample{sample.Value, sample.Width, 0})
+		i++
+	inserted:
+		s.n += sample.Width
+		r += sample.Width
+	}
+	s.compress()
+}
+
+func (s *stream) count() int {
+	return int(s.n)
+}
+
+func (s *stream) query(q float64) float64 {
+	t := math.Ceil(q * s.n)
+	t += math.Ceil(s.ƒ(s, t) / 2)
+	p := s.l[0]
+	var r float64
+	for _, c := range s.l[1:] {
+		r += p.Width
+		if r+c.Width+c.Delta > t {
+			return p.Value
+		}
+		p = c
+	}
+	return p.Value
+}
+
+func (s *stream) compress() {
+	if len(s.l) < 2 {
+		return
+	}
+	x := s.l[len(s.l)-1]
+	xi := len(s.l) - 1
+	r := s.n - 1 - x.Width
+
+	for i := len(s.l) - 2; i >= 0; i-- {
+		c := s.l[i]
+		if c.Width+x.Width+x.Delta <= s.ƒ(s, r) {
+			x.Width += c.Width
+			s.l[xi] = x
+			// Remove element at i.
+			copy(s.l[i:], s.l[i+1:])
+			s.l = s.l[:len(s.l)-1]
+			xi -= 1
+		} else {
+			x = c
+			xi = i
+		}
+		r -= c.Width
+	}
+}
+
+func (s *stream) samples() Samples {
+	samples := make(Samples, len(s.l))
+	copy(samples, s.l)
+	return samples
+}

vendor/github.com/go-redis/redis/.gitignore

@@ -0,0 +1,2 @@
+*.rdb
+testdata/*/

vendor/github.com/go-redis/redis/.travis.yml

@@ -0,0 +1,21 @@
+sudo: false
+language: go
+
+services:
+  - redis-server
+
+go:
+  - 1.7.x
+  - 1.8.x
+  - 1.9.x
+  - 1.10.x
+  - 1.11.x
+  - tip
+
+matrix:
+  allow_failures:
+    - go: tip
+
+install:
+  - go get github.com/onsi/ginkgo
+  - go get github.com/onsi/gomega

vendor/github.com/go-redis/redis/CHANGELOG.md

@@ -0,0 +1,25 @@
+# Changelog
+
+## Unreleased
+
+- Cluster and Ring pipelines process commands for each node in its own goroutine.
+
+## 6.14
+
+- Added Options.MinIdleConns.
+- Added Options.MaxConnAge.
+- PoolStats.FreeConns is renamed to PoolStats.IdleConns.
+- Add Client.Do to simplify creating custom commands.
+- Add Cmd.String, Cmd.Int, Cmd.Int64, Cmd.Uint64, Cmd.Float64, and Cmd.Bool helpers.
+- Lower memory usage.
+
+## v6.13
+
+- Ring got new options called `HashReplicas` and `Hash`. It is recommended to set `HashReplicas = 1000` for better keys distribution between shards.
+- Cluster client was optimized to use much less memory when reloading cluster state.
+- PubSub.ReceiveMessage is re-worked to not use ReceiveTimeout so it does not lose data when timeout occurres. In most cases it is recommended to use PubSub.Channel instead.
+- Dialer.KeepAlive is set to 5 minutes by default.
+
+## v6.12
+
+- ClusterClient got new option called `ClusterSlots` which allows to build cluster of normal Redis Servers that don't have cluster mode enabled. See https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup

vendor/github.com/go-redis/redis/LICENSE

@@ -0,0 +1,25 @@
+Copyright (c) 2013 The github.com/go-redis/redis Authors.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/go-redis/redis/Makefile

@@ -0,0 +1,20 @@
+all: testdeps
+	go test ./...
+	go test ./... -short -race
+	env GOOS=linux GOARCH=386 go test ./...
+	go vet
+
+testdeps: testdata/redis/src/redis-server
+
+bench: testdeps
+	go test ./... -test.run=NONE -test.bench=. -test.benchmem
+
+.PHONY: all test testdeps bench
+
+testdata/redis:
+	mkdir -p $@
+	wget -qO- https://github.com/antirez/redis/archive/unstable.tar.gz | tar xvz --strip-components=1 -C $@
+
+testdata/redis/src/redis-server: testdata/redis
+	sed -i.bak 's/libjemalloc.a/libjemalloc.a -lrt/g' $</src/Makefile
+	cd $< && make all

vendor/github.com/go-redis/redis/README.md

@@ -0,0 +1,146 @@
+# Redis client for Golang
+
+[![Build Status](https://travis-ci.org/go-redis/redis.png?branch=master)](https://travis-ci.org/go-redis/redis)
+[![GoDoc](https://godoc.org/github.com/go-redis/redis?status.svg)](https://godoc.org/github.com/go-redis/redis)
+[![Airbrake](https://img.shields.io/badge/kudos-airbrake.io-orange.svg)](https://airbrake.io)
+
+Supports:
+
+- Redis 3 commands except QUIT, MONITOR, SLOWLOG and SYNC.
+- Automatic connection pooling with [circuit breaker](https://en.wikipedia.org/wiki/Circuit_breaker_design_pattern) support.
+- [Pub/Sub](https://godoc.org/github.com/go-redis/redis#PubSub).
+- [Transactions](https://godoc.org/github.com/go-redis/redis#Multi).
+- [Pipeline](https://godoc.org/github.com/go-redis/redis#example-Client-Pipeline) and [TxPipeline](https://godoc.org/github.com/go-redis/redis#example-Client-TxPipeline).
+- [Scripting](https://godoc.org/github.com/go-redis/redis#Script).
+- [Timeouts](https://godoc.org/github.com/go-redis/redis#Options).
+- [Redis Sentinel](https://godoc.org/github.com/go-redis/redis#NewFailoverClient).
+- [Redis Cluster](https://godoc.org/github.com/go-redis/redis#NewClusterClient).
+- [Cluster of Redis Servers](https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup) without using cluster mode and Redis Sentinel.
+- [Ring](https://godoc.org/github.com/go-redis/redis#NewRing).
+- [Instrumentation](https://godoc.org/github.com/go-redis/redis#ex-package--Instrumentation).
+- [Cache friendly](https://github.com/go-redis/cache).
+- [Rate limiting](https://github.com/go-redis/redis_rate).
+- [Distributed Locks](https://github.com/bsm/redis-lock).
+
+API docs: https://godoc.org/github.com/go-redis/redis.
+Examples: https://godoc.org/github.com/go-redis/redis#pkg-examples.
+
+## Installation
+
+Install:
+
+```shell
+go get -u github.com/go-redis/redis
+```
+
+Import:
+
+```go
+import "github.com/go-redis/redis"
+```
+
+## Quickstart
+
+```go
+func ExampleNewClient() {
+	client := redis.NewClient(&redis.Options{
+		Addr:     "localhost:6379",
+		Password: "", // no password set
+		DB:       0,  // use default DB
+	})
+
+	pong, err := client.Ping().Result()
+	fmt.Println(pong, err)
+	// Output: PONG <nil>
+}
+
+func ExampleClient() {
+	err := client.Set("key", "value", 0).Err()
+	if err != nil {
+		panic(err)
+	}
+
+	val, err := client.Get("key").Result()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println("key", val)
+
+	val2, err := client.Get("key2").Result()
+	if err == redis.Nil {
+		fmt.Println("key2 does not exist")
+	} else if err != nil {
+		panic(err)
+	} else {
+		fmt.Println("key2", val2)
+	}
+	// Output: key value
+	// key2 does not exist
+}
+```
+
+## Howto
+
+Please go through [examples](https://godoc.org/github.com/go-redis/redis#pkg-examples) to get an idea how to use this package.
+
+## Look and feel
+
+Some corner cases:
+
+```go
+// SET key value EX 10 NX
+set, err := client.SetNX("key", "value", 10*time.Second).Result()
+
+// SORT list LIMIT 0 2 ASC
+vals, err := client.Sort("list", redis.Sort{Offset: 0, Count: 2, Order: "ASC"}).Result()
+
+// ZRANGEBYSCORE zset -inf +inf WITHSCORES LIMIT 0 2
+vals, err := client.ZRangeByScoreWithScores("zset", redis.ZRangeBy{
+	Min: "-inf",
+	Max: "+inf",
+	Offset: 0,
+	Count: 2,
+}).Result()
+
+// ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3 AGGREGATE SUM
+vals, err := client.ZInterStore("out", redis.ZStore{Weights: []int64{2, 3}}, "zset1", "zset2").Result()
+
+// EVAL "return {KEYS[1],ARGV[1]}" 1 "key" "hello"
+vals, err := client.Eval("return {KEYS[1],ARGV[1]}", []string{"key"}, "hello").Result()
+```
+
+## Benchmark
+
+go-redis vs redigo:
+
+```
+BenchmarkSetGoRedis10Conns64Bytes-4 	  200000	      7621 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns64Bytes-4	  200000	      7554 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns1KB-4     	  200000	      7697 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns1KB-4    	  200000	      7688 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns10KB-4    	  200000	      9214 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns10KB-4   	  200000	      9181 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns1MB-4     	    2000	    583242 ns/op	    2337 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns1MB-4    	    2000	    583089 ns/op	    2338 B/op	       6 allocs/op
+BenchmarkSetRedigo10Conns64Bytes-4  	  200000	      7576 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns64Bytes-4 	  200000	      7782 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns1KB-4      	  200000	      7958 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns1KB-4     	  200000	      7725 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns10KB-4     	  100000	     18442 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns10KB-4    	  100000	     18818 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns1MB-4      	    2000	    668829 ns/op	     226 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns1MB-4     	    2000	    679542 ns/op	     226 B/op	       7 allocs/op
+```
+
+Redis Cluster:
+
+```
+BenchmarkRedisPing-4                	  200000	      6983 ns/op	     116 B/op	       4 allocs/op
+BenchmarkRedisClusterPing-4         	  100000	     11535 ns/op	     117 B/op	       4 allocs/op
+```
+
+## See also
+
+- [Golang PostgreSQL ORM](https://github.com/go-pg/pg)
+- [Golang msgpack](https://github.com/vmihailenco/msgpack)
+- [Golang message task queue](https://github.com/go-msgqueue/msgqueue)

vendor/github.com/go-redis/redis/cluster_commands.go

@@ -0,0 +1,22 @@
+package redis
+
+import "sync/atomic"
+
+func (c *ClusterClient) DBSize() *IntCmd {
+	cmd := NewIntCmd("dbsize")
+	var size int64
+	err := c.ForEachMaster(func(master *Client) error {
+		n, err := master.DBSize().Result()
+		if err != nil {
+			return err
+		}
+		atomic.AddInt64(&size, n)
+		return nil
+	})
+	if err != nil {
+		cmd.setErr(err)
+		return cmd
+	}
+	cmd.val = size
+	return cmd
+}

vendor/github.com/go-redis/redis/doc.go

@@ -0,0 +1,4 @@
+/*
+Package redis implements a Redis client.
+*/
+package redis

vendor/github.com/go-redis/redis/internal/consistenthash/consistenthash.go

@@ -0,0 +1,81 @@
+/*
+Copyright 2013 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package consistenthash provides an implementation of a ring hash.
+package consistenthash
+
+import (
+	"hash/crc32"
+	"sort"
+	"strconv"
+)
+
+type Hash func(data []byte) uint32
+
+type Map struct {
+	hash     Hash
+	replicas int
+	keys     []int // Sorted
+	hashMap  map[int]string
+}
+
+func New(replicas int, fn Hash) *Map {
+	m := &Map{
+		replicas: replicas,
+		hash:     fn,
+		hashMap:  make(map[int]string),
+	}
+	if m.hash == nil {
+		m.hash = crc32.ChecksumIEEE
+	}
+	return m
+}
+
+// Returns true if there are no items available.
+func (m *Map) IsEmpty() bool {
+	return len(m.keys) == 0
+}
+
+// Adds some keys to the hash.
+func (m *Map) Add(keys ...string) {
+	for _, key := range keys {
+		for i := 0; i < m.replicas; i++ {
+			hash := int(m.hash([]byte(strconv.Itoa(i) + key)))
+			m.keys = append(m.keys, hash)
+			m.hashMap[hash] = key
+		}
+	}
+	sort.Ints(m.keys)
+}
+
+// Gets the closest item in the hash to the provided key.
+func (m *Map) Get(key string) string {
+	if m.IsEmpty() {
+		return ""
+	}
+
+	hash := int(m.hash([]byte(key)))
+
+	// Binary search for appropriate replica.
+	idx := sort.Search(len(m.keys), func(i int) bool { return m.keys[i] >= hash })
+
+	// Means we have cycled back to the first replica.
+	if idx == len(m.keys) {
+		idx = 0
+	}
+
+	return m.hashMap[m.keys[idx]]
+}

vendor/github.com/go-redis/redis/internal/error.go

@@ -0,0 +1,84 @@
+package internal
+
+import (
+	"io"
+	"net"
+	"strings"
+
+	"github.com/go-redis/redis/internal/proto"
+)
+
+func IsRetryableError(err error, retryTimeout bool) bool {
+	if err == nil {
+		return false
+	}
+	if err == io.EOF {
+		return true
+	}
+	if netErr, ok := err.(net.Error); ok {
+		if netErr.Timeout() {
+			return retryTimeout
+		}
+		return true
+	}
+	s := err.Error()
+	if s == "ERR max number of clients reached" {
+		return true
+	}
+	if strings.HasPrefix(s, "LOADING ") {
+		return true
+	}
+	if strings.HasPrefix(s, "READONLY ") {
+		return true
+	}
+	if strings.HasPrefix(s, "CLUSTERDOWN ") {
+		return true
+	}
+	return false
+}
+
+func IsRedisError(err error) bool {
+	_, ok := err.(proto.RedisError)
+	return ok
+}
+
+func IsBadConn(err error, allowTimeout bool) bool {
+	if err == nil {
+		return false
+	}
+	if IsRedisError(err) {
+		return strings.HasPrefix(err.Error(), "READONLY ")
+	}
+	if allowTimeout {
+		if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
+			return false
+		}
+	}
+	return true
+}
+
+func IsMovedError(err error) (moved bool, ask bool, addr string) {
+	if !IsRedisError(err) {
+		return
+	}
+
+	s := err.Error()
+	if strings.HasPrefix(s, "MOVED ") {
+		moved = true
+	} else if strings.HasPrefix(s, "ASK ") {
+		ask = true
+	} else {
+		return
+	}
+
+	ind := strings.LastIndex(s, " ")
+	if ind == -1 {
+		return false, false, ""
+	}
+	addr = s[ind+1:]
+	return
+}
+
+func IsLoadingError(err error) bool {
+	return strings.HasPrefix(err.Error(), "LOADING ")
+}

vendor/github.com/go-redis/redis/internal/hashtag/hashtag.go

@@ -0,0 +1,77 @@
+package hashtag
+
+import (
+	"math/rand"
+	"strings"
+)
+
+const slotNumber = 16384
+
+// CRC16 implementation according to CCITT standards.
+// Copyright 2001-2010 Georges Menie (www.menie.org)
+// Copyright 2013 The Go Authors. All rights reserved.
+// http://redis.io/topics/cluster-spec#appendix-a-crc16-reference-implementation-in-ansi-c
+var crc16tab = [256]uint16{
+	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
+}
+
+func Key(key string) string {
+	if s := strings.IndexByte(key, '{'); s > -1 {
+		if e := strings.IndexByte(key[s+1:], '}'); e > 0 {
+			return key[s+1 : s+e+1]
+		}
+	}
+	return key
+}
+
+func RandomSlot() int {
+	return rand.Intn(slotNumber)
+}
+
+// hashSlot returns a consistent slot number between 0 and 16383
+// for any given string key.
+func Slot(key string) int {
+	if key == "" {
+		return RandomSlot()
+	}
+	key = Key(key)
+	return int(crc16sum(key)) % slotNumber
+}
+
+func crc16sum(key string) (crc uint16) {
+	for i := 0; i < len(key); i++ {
+		crc = (crc << 8) ^ crc16tab[(byte(crc>>8)^key[i])&0x00ff]
+	}
+	return
+}

vendor/github.com/go-redis/redis/internal/internal.go

@@ -0,0 +1,24 @@
+package internal
+
+import (
+	"math/rand"
+	"time"
+)
+
+// Retry backoff with jitter sleep to prevent overloaded conditions during intervals
+// https://www.awsarchitectureblog.com/2015/03/backoff.html
+func RetryBackoff(retry int, minBackoff, maxBackoff time.Duration) time.Duration {
+	if retry < 0 {
+		retry = 0
+	}
+
+	backoff := minBackoff << uint(retry)
+	if backoff > maxBackoff || backoff < minBackoff {
+		backoff = maxBackoff
+	}
+
+	if backoff == 0 {
+		return 0
+	}
+	return time.Duration(rand.Int63n(int64(backoff)))
+}

vendor/github.com/go-redis/redis/internal/log.go

@@ -0,0 +1,15 @@
+package internal
+
+import (
+	"fmt"
+	"log"
+)
+
+var Logger *log.Logger
+
+func Logf(s string, args ...interface{}) {
+	if Logger == nil {
+		return
+	}
+	Logger.Output(2, fmt.Sprintf(s, args...))
+}

vendor/github.com/go-redis/redis/internal/once.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2014 The Camlistore Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package internal
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+// A Once will perform a successful action exactly once.
+//
+// Unlike a sync.Once, this Once's func returns an error
+// and is re-armed on failure.
+type Once struct {
+	m    sync.Mutex
+	done uint32
+}
+
+// Do calls the function f if and only if Do has not been invoked
+// without error for this instance of Once.  In other words, given
+// 	var once Once
+// if once.Do(f) is called multiple times, only the first call will
+// invoke f, even if f has a different value in each invocation unless
+// f returns an error.  A new instance of Once is required for each
+// function to execute.
+//
+// Do is intended for initialization that must be run exactly once.  Since f
+// is niladic, it may be necessary to use a function literal to capture the
+// arguments to a function to be invoked by Do:
+// 	err := config.once.Do(func() error { return config.init(filename) })
+func (o *Once) Do(f func() error) error {
+	if atomic.LoadUint32(&o.done) == 1 {
+		return nil
+	}
+	// Slow-path.
+	o.m.Lock()
+	defer o.m.Unlock()
+	var err error
+	if o.done == 0 {
+		err = f()
+		if err == nil {
+			atomic.StoreUint32(&o.done, 1)
+		}
+	}
+	return err
+}

vendor/github.com/go-redis/redis/internal/pool/conn.go

@@ -0,0 +1,93 @@
+package pool
+
+import (
+	"net"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal/proto"
+)
+
+var noDeadline = time.Time{}
+
+type Conn struct {
+	netConn net.Conn
+
+	rd       *proto.Reader
+	rdLocked bool
+	wr       *proto.Writer
+
+	InitedAt time.Time
+	pooled   bool
+	usedAt   atomic.Value
+}
+
+func NewConn(netConn net.Conn) *Conn {
+	cn := &Conn{
+		netConn: netConn,
+	}
+	cn.rd = proto.NewReader(netConn)
+	cn.wr = proto.NewWriter(netConn)
+	cn.SetUsedAt(time.Now())
+	return cn
+}
+
+func (cn *Conn) UsedAt() time.Time {
+	return cn.usedAt.Load().(time.Time)
+}
+
+func (cn *Conn) SetUsedAt(tm time.Time) {
+	cn.usedAt.Store(tm)
+}
+
+func (cn *Conn) SetNetConn(netConn net.Conn) {
+	cn.netConn = netConn
+	cn.rd.Reset(netConn)
+	cn.wr.Reset(netConn)
+}
+
+func (cn *Conn) setReadTimeout(timeout time.Duration) error {
+	now := time.Now()
+	cn.SetUsedAt(now)
+	if timeout > 0 {
+		return cn.netConn.SetReadDeadline(now.Add(timeout))
+	}
+	return cn.netConn.SetReadDeadline(noDeadline)
+}
+
+func (cn *Conn) setWriteTimeout(timeout time.Duration) error {
+	now := time.Now()
+	cn.SetUsedAt(now)
+	if timeout > 0 {
+		return cn.netConn.SetWriteDeadline(now.Add(timeout))
+	}
+	return cn.netConn.SetWriteDeadline(noDeadline)
+}
+
+func (cn *Conn) Write(b []byte) (int, error) {
+	return cn.netConn.Write(b)
+}
+
+func (cn *Conn) RemoteAddr() net.Addr {
+	return cn.netConn.RemoteAddr()
+}
+
+func (cn *Conn) WithReader(timeout time.Duration, fn func(rd *proto.Reader) error) error {
+	_ = cn.setReadTimeout(timeout)
+	return fn(cn.rd)
+}
+
+func (cn *Conn) WithWriter(timeout time.Duration, fn func(wr *proto.Writer) error) error {
+	_ = cn.setWriteTimeout(timeout)
+
+	firstErr := fn(cn.wr)
+	err := cn.wr.Flush()
+	if err != nil && firstErr == nil {
+		firstErr = err
+	}
+	return firstErr
+}
+
+func (cn *Conn) Close() error {
+	return cn.netConn.Close()
+}

vendor/github.com/go-redis/redis/internal/pool/pool.go

@@ -0,0 +1,476 @@
+package pool
+
+import (
+	"errors"
+	"net"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+)
+
+var ErrClosed = errors.New("redis: client is closed")
+var ErrPoolTimeout = errors.New("redis: connection pool timeout")
+
+var timers = sync.Pool{
+	New: func() interface{} {
+		t := time.NewTimer(time.Hour)
+		t.Stop()
+		return t
+	},
+}
+
+// Stats contains pool state information and accumulated stats.
+type Stats struct {
+	Hits     uint32 // number of times free connection was found in the pool
+	Misses   uint32 // number of times free connection was NOT found in the pool
+	Timeouts uint32 // number of times a wait timeout occurred
+
+	TotalConns uint32 // number of total connections in the pool
+	IdleConns  uint32 // number of idle connections in the pool
+	StaleConns uint32 // number of stale connections removed from the pool
+}
+
+type Pooler interface {
+	NewConn() (*Conn, error)
+	CloseConn(*Conn) error
+
+	Get() (*Conn, error)
+	Put(*Conn)
+	Remove(*Conn)
+
+	Len() int
+	IdleLen() int
+	Stats() *Stats
+
+	Close() error
+}
+
+type Options struct {
+	Dialer  func() (net.Conn, error)
+	OnClose func(*Conn) error
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+}
+
+type ConnPool struct {
+	opt *Options
+
+	dialErrorsNum uint32 // atomic
+
+	lastDialErrorMu sync.RWMutex
+	lastDialError   error
+
+	queue chan struct{}
+
+	connsMu      sync.Mutex
+	conns        []*Conn
+	idleConns    []*Conn
+	poolSize     int
+	idleConnsLen int
+
+	stats Stats
+
+	_closed uint32 // atomic
+}
+
+var _ Pooler = (*ConnPool)(nil)
+
+func NewConnPool(opt *Options) *ConnPool {
+	p := &ConnPool{
+		opt: opt,
+
+		queue:     make(chan struct{}, opt.PoolSize),
+		conns:     make([]*Conn, 0, opt.PoolSize),
+		idleConns: make([]*Conn, 0, opt.PoolSize),
+	}
+
+	for i := 0; i < opt.MinIdleConns; i++ {
+		p.checkMinIdleConns()
+	}
+
+	if opt.IdleTimeout > 0 && opt.IdleCheckFrequency > 0 {
+		go p.reaper(opt.IdleCheckFrequency)
+	}
+
+	return p
+}
+
+func (p *ConnPool) checkMinIdleConns() {
+	if p.opt.MinIdleConns == 0 {
+		return
+	}
+	if p.poolSize < p.opt.PoolSize && p.idleConnsLen < p.opt.MinIdleConns {
+		p.poolSize++
+		p.idleConnsLen++
+		go p.addIdleConn()
+	}
+}
+
+func (p *ConnPool) addIdleConn() {
+	cn, err := p.newConn(true)
+	if err != nil {
+		return
+	}
+
+	p.connsMu.Lock()
+	p.conns = append(p.conns, cn)
+	p.idleConns = append(p.idleConns, cn)
+	p.connsMu.Unlock()
+}
+
+func (p *ConnPool) NewConn() (*Conn, error) {
+	return p._NewConn(false)
+}
+
+func (p *ConnPool) _NewConn(pooled bool) (*Conn, error) {
+	cn, err := p.newConn(pooled)
+	if err != nil {
+		return nil, err
+	}
+
+	p.connsMu.Lock()
+	p.conns = append(p.conns, cn)
+	if pooled {
+		if p.poolSize < p.opt.PoolSize {
+			p.poolSize++
+		} else {
+			cn.pooled = false
+		}
+	}
+	p.connsMu.Unlock()
+	return cn, nil
+}
+
+func (p *ConnPool) newConn(pooled bool) (*Conn, error) {
+	if p.closed() {
+		return nil, ErrClosed
+	}
+
+	if atomic.LoadUint32(&p.dialErrorsNum) >= uint32(p.opt.PoolSize) {
+		return nil, p.getLastDialError()
+	}
+
+	netConn, err := p.opt.Dialer()
+	if err != nil {
+		p.setLastDialError(err)
+		if atomic.AddUint32(&p.dialErrorsNum, 1) == uint32(p.opt.PoolSize) {
+			go p.tryDial()
+		}
+		return nil, err
+	}
+
+	cn := NewConn(netConn)
+	cn.pooled = pooled
+	return cn, nil
+}
+
+func (p *ConnPool) tryDial() {
+	for {
+		if p.closed() {
+			return
+		}
+
+		conn, err := p.opt.Dialer()
+		if err != nil {
+			p.setLastDialError(err)
+			time.Sleep(time.Second)
+			continue
+		}
+
+		atomic.StoreUint32(&p.dialErrorsNum, 0)
+		_ = conn.Close()
+		return
+	}
+}
+
+func (p *ConnPool) setLastDialError(err error) {
+	p.lastDialErrorMu.Lock()
+	p.lastDialError = err
+	p.lastDialErrorMu.Unlock()
+}
+
+func (p *ConnPool) getLastDialError() error {
+	p.lastDialErrorMu.RLock()
+	err := p.lastDialError
+	p.lastDialErrorMu.RUnlock()
+	return err
+}
+
+// Get returns existed connection from the pool or creates a new one.
+func (p *ConnPool) Get() (*Conn, error) {
+	if p.closed() {
+		return nil, ErrClosed
+	}
+
+	err := p.waitTurn()
+	if err != nil {
+		return nil, err
+	}
+
+	for {
+		p.connsMu.Lock()
+		cn := p.popIdle()
+		p.connsMu.Unlock()
+
+		if cn == nil {
+			break
+		}
+
+		if p.isStaleConn(cn) {
+			_ = p.CloseConn(cn)
+			continue
+		}
+
+		atomic.AddUint32(&p.stats.Hits, 1)
+		return cn, nil
+	}
+
+	atomic.AddUint32(&p.stats.Misses, 1)
+
+	newcn, err := p._NewConn(true)
+	if err != nil {
+		p.freeTurn()
+		return nil, err
+	}
+
+	return newcn, nil
+}
+
+func (p *ConnPool) getTurn() {
+	p.queue <- struct{}{}
+}
+
+func (p *ConnPool) waitTurn() error {
+	select {
+	case p.queue <- struct{}{}:
+		return nil
+	default:
+		timer := timers.Get().(*time.Timer)
+		timer.Reset(p.opt.PoolTimeout)
+
+		select {
+		case p.queue <- struct{}{}:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			timers.Put(timer)
+			return nil
+		case <-timer.C:
+			timers.Put(timer)
+			atomic.AddUint32(&p.stats.Timeouts, 1)
+			return ErrPoolTimeout
+		}
+	}
+}
+
+func (p *ConnPool) freeTurn() {
+	<-p.queue
+}
+
+func (p *ConnPool) popIdle() *Conn {
+	if len(p.idleConns) == 0 {
+		return nil
+	}
+
+	idx := len(p.idleConns) - 1
+	cn := p.idleConns[idx]
+	p.idleConns = p.idleConns[:idx]
+	p.idleConnsLen--
+	p.checkMinIdleConns()
+	return cn
+}
+
+func (p *ConnPool) Put(cn *Conn) {
+	if !cn.pooled {
+		p.Remove(cn)
+		return
+	}
+
+	p.connsMu.Lock()
+	p.idleConns = append(p.idleConns, cn)
+	p.idleConnsLen++
+	p.connsMu.Unlock()
+	p.freeTurn()
+}
+
+func (p *ConnPool) Remove(cn *Conn) {
+	p.removeConn(cn)
+	p.freeTurn()
+	_ = p.closeConn(cn)
+}
+
+func (p *ConnPool) CloseConn(cn *Conn) error {
+	p.removeConn(cn)
+	return p.closeConn(cn)
+}
+
+func (p *ConnPool) removeConn(cn *Conn) {
+	p.connsMu.Lock()
+	for i, c := range p.conns {
+		if c == cn {
+			p.conns = append(p.conns[:i], p.conns[i+1:]...)
+			if cn.pooled {
+				p.poolSize--
+				p.checkMinIdleConns()
+			}
+			break
+		}
+	}
+	p.connsMu.Unlock()
+}
+
+func (p *ConnPool) closeConn(cn *Conn) error {
+	if p.opt.OnClose != nil {
+		_ = p.opt.OnClose(cn)
+	}
+	return cn.Close()
+}
+
+// Len returns total number of connections.
+func (p *ConnPool) Len() int {
+	p.connsMu.Lock()
+	n := len(p.conns)
+	p.connsMu.Unlock()
+	return n
+}
+
+// IdleLen returns number of idle connections.
+func (p *ConnPool) IdleLen() int {
+	p.connsMu.Lock()
+	n := p.idleConnsLen
+	p.connsMu.Unlock()
+	return n
+}
+
+func (p *ConnPool) Stats() *Stats {
+	idleLen := p.IdleLen()
+	return &Stats{
+		Hits:     atomic.LoadUint32(&p.stats.Hits),
+		Misses:   atomic.LoadUint32(&p.stats.Misses),
+		Timeouts: atomic.LoadUint32(&p.stats.Timeouts),
+
+		TotalConns: uint32(p.Len()),
+		IdleConns:  uint32(idleLen),
+		StaleConns: atomic.LoadUint32(&p.stats.StaleConns),
+	}
+}
+
+func (p *ConnPool) closed() bool {
+	return atomic.LoadUint32(&p._closed) == 1
+}
+
+func (p *ConnPool) Filter(fn func(*Conn) bool) error {
+	var firstErr error
+	p.connsMu.Lock()
+	for _, cn := range p.conns {
+		if fn(cn) {
+			if err := p.closeConn(cn); err != nil && firstErr == nil {
+				firstErr = err
+			}
+		}
+	}
+	p.connsMu.Unlock()
+	return firstErr
+}
+
+func (p *ConnPool) Close() error {
+	if !atomic.CompareAndSwapUint32(&p._closed, 0, 1) {
+		return ErrClosed
+	}
+
+	var firstErr error
+	p.connsMu.Lock()
+	for _, cn := range p.conns {
+		if err := p.closeConn(cn); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	p.conns = nil
+	p.poolSize = 0
+	p.idleConns = nil
+	p.idleConnsLen = 0
+	p.connsMu.Unlock()
+
+	return firstErr
+}
+
+func (p *ConnPool) reapStaleConn() *Conn {
+	if len(p.idleConns) == 0 {
+		return nil
+	}
+
+	cn := p.idleConns[0]
+	if !p.isStaleConn(cn) {
+		return nil
+	}
+
+	p.idleConns = append(p.idleConns[:0], p.idleConns[1:]...)
+	p.idleConnsLen--
+
+	return cn
+}
+
+func (p *ConnPool) ReapStaleConns() (int, error) {
+	var n int
+	for {
+		p.getTurn()
+
+		p.connsMu.Lock()
+		cn := p.reapStaleConn()
+		p.connsMu.Unlock()
+
+		if cn != nil {
+			p.removeConn(cn)
+		}
+
+		p.freeTurn()
+
+		if cn != nil {
+			p.closeConn(cn)
+			n++
+		} else {
+			break
+		}
+	}
+	return n, nil
+}
+
+func (p *ConnPool) reaper(frequency time.Duration) {
+	ticker := time.NewTicker(frequency)
+	defer ticker.Stop()
+
+	for range ticker.C {
+		if p.closed() {
+			break
+		}
+		n, err := p.ReapStaleConns()
+		if err != nil {
+			internal.Logf("ReapStaleConns failed: %s", err)
+			continue
+		}
+		atomic.AddUint32(&p.stats.StaleConns, uint32(n))
+	}
+}
+
+func (p *ConnPool) isStaleConn(cn *Conn) bool {
+	if p.opt.IdleTimeout == 0 && p.opt.MaxConnAge == 0 {
+		return false
+	}
+
+	now := time.Now()
+	if p.opt.IdleTimeout > 0 && now.Sub(cn.UsedAt()) >= p.opt.IdleTimeout {
+		return true
+	}
+	if p.opt.MaxConnAge > 0 && now.Sub(cn.InitedAt) >= p.opt.MaxConnAge {
+		return true
+	}
+
+	return false
+}

vendor/github.com/go-redis/redis/internal/pool/pool_single.go

@@ -0,0 +1,53 @@
+package pool
+
+type SingleConnPool struct {
+	cn *Conn
+}
+
+var _ Pooler = (*SingleConnPool)(nil)
+
+func NewSingleConnPool(cn *Conn) *SingleConnPool {
+	return &SingleConnPool{
+		cn: cn,
+	}
+}
+
+func (p *SingleConnPool) NewConn() (*Conn, error) {
+	panic("not implemented")
+}
+
+func (p *SingleConnPool) CloseConn(*Conn) error {
+	panic("not implemented")
+}
+
+func (p *SingleConnPool) Get() (*Conn, error) {
+	return p.cn, nil
+}
+
+func (p *SingleConnPool) Put(cn *Conn) {
+	if p.cn != cn {
+		panic("p.cn != cn")
+	}
+}
+
+func (p *SingleConnPool) Remove(cn *Conn) {
+	if p.cn != cn {
+		panic("p.cn != cn")
+	}
+}
+
+func (p *SingleConnPool) Len() int {
+	return 1
+}
+
+func (p *SingleConnPool) IdleLen() int {
+	return 0
+}
+
+func (p *SingleConnPool) Stats() *Stats {
+	return nil
+}
+
+func (p *SingleConnPool) Close() error {
+	return nil
+}

vendor/github.com/go-redis/redis/internal/pool/pool_sticky.go

@@ -0,0 +1,109 @@
+package pool
+
+import "sync"
+
+type StickyConnPool struct {
+	pool     *ConnPool
+	reusable bool
+
+	cn     *Conn
+	closed bool
+	mu     sync.Mutex
+}
+
+var _ Pooler = (*StickyConnPool)(nil)
+
+func NewStickyConnPool(pool *ConnPool, reusable bool) *StickyConnPool {
+	return &StickyConnPool{
+		pool:     pool,
+		reusable: reusable,
+	}
+}
+
+func (p *StickyConnPool) NewConn() (*Conn, error) {
+	panic("not implemented")
+}
+
+func (p *StickyConnPool) CloseConn(*Conn) error {
+	panic("not implemented")
+}
+
+func (p *StickyConnPool) Get() (*Conn, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.closed {
+		return nil, ErrClosed
+	}
+	if p.cn != nil {
+		return p.cn, nil
+	}
+
+	cn, err := p.pool.Get()
+	if err != nil {
+		return nil, err
+	}
+
+	p.cn = cn
+	return cn, nil
+}
+
+func (p *StickyConnPool) putUpstream() {
+	p.pool.Put(p.cn)
+	p.cn = nil
+}
+
+func (p *StickyConnPool) Put(cn *Conn) {}
+
+func (p *StickyConnPool) removeUpstream() {
+	p.pool.Remove(p.cn)
+	p.cn = nil
+}
+
+func (p *StickyConnPool) Remove(cn *Conn) {
+	p.removeUpstream()
+}
+
+func (p *StickyConnPool) Len() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.cn == nil {
+		return 0
+	}
+	return 1
+}
+
+func (p *StickyConnPool) IdleLen() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.cn == nil {
+		return 1
+	}
+	return 0
+}
+
+func (p *StickyConnPool) Stats() *Stats {
+	return nil
+}
+
+func (p *StickyConnPool) Close() error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.closed {
+		return ErrClosed
+	}
+	p.closed = true
+
+	if p.cn != nil {
+		if p.reusable {
+			p.putUpstream()
+		} else {
+			p.removeUpstream()
+		}
+	}
+
+	return nil
+}

vendor/github.com/go-redis/redis/internal/proto/reader.go

@@ -0,0 +1,290 @@
+package proto
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strconv"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+const (
+	ErrorReply  = '-'
+	StatusReply = '+'
+	IntReply    = ':'
+	StringReply = '$'
+	ArrayReply  = '*'
+)
+
+//------------------------------------------------------------------------------
+
+const Nil = RedisError("redis: nil")
+
+type RedisError string
+
+func (e RedisError) Error() string { return string(e) }
+
+//------------------------------------------------------------------------------
+
+type MultiBulkParse func(*Reader, int64) (interface{}, error)
+
+type Reader struct {
+	rd   *bufio.Reader
+	_buf []byte
+}
+
+func NewReader(rd io.Reader) *Reader {
+	return &Reader{
+		rd:   bufio.NewReader(rd),
+		_buf: make([]byte, 64),
+	}
+}
+
+func (r *Reader) Reset(rd io.Reader) {
+	r.rd.Reset(rd)
+}
+
+func (r *Reader) ReadLine() ([]byte, error) {
+	line, isPrefix, err := r.rd.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	if isPrefix {
+		return nil, bufio.ErrBufferFull
+	}
+	if len(line) == 0 {
+		return nil, fmt.Errorf("redis: reply is empty")
+	}
+	if isNilReply(line) {
+		return nil, Nil
+	}
+	return line, nil
+}
+
+func (r *Reader) ReadReply(m MultiBulkParse) (interface{}, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case StatusReply:
+		return string(line[1:]), nil
+	case IntReply:
+		return util.ParseInt(line[1:], 10, 64)
+	case StringReply:
+		return r.readStringReply(line)
+	case ArrayReply:
+		n, err := parseArrayLen(line)
+		if err != nil {
+			return nil, err
+		}
+		return m(r, n)
+	}
+	return nil, fmt.Errorf("redis: can't parse %.100q", line)
+}
+
+func (r *Reader) ReadIntReply() (int64, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return 0, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return 0, ParseErrorReply(line)
+	case IntReply:
+		return util.ParseInt(line[1:], 10, 64)
+	default:
+		return 0, fmt.Errorf("redis: can't parse int reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadString() (string, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return "", err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return "", ParseErrorReply(line)
+	case StringReply:
+		return r.readStringReply(line)
+	case StatusReply:
+		return string(line[1:]), nil
+	case IntReply:
+		return string(line[1:]), nil
+	default:
+		return "", fmt.Errorf("redis: can't parse reply=%.100q reading string", line)
+	}
+}
+
+func (r *Reader) readStringReply(line []byte) (string, error) {
+	if isNilReply(line) {
+		return "", Nil
+	}
+
+	replyLen, err := strconv.Atoi(string(line[1:]))
+	if err != nil {
+		return "", err
+	}
+
+	b := make([]byte, replyLen+2)
+	_, err = io.ReadFull(r.rd, b)
+	if err != nil {
+		return "", err
+	}
+
+	return util.BytesToString(b[:replyLen]), nil
+}
+
+func (r *Reader) ReadArrayReply(m MultiBulkParse) (interface{}, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case ArrayReply:
+		n, err := parseArrayLen(line)
+		if err != nil {
+			return nil, err
+		}
+		return m(r, n)
+	default:
+		return nil, fmt.Errorf("redis: can't parse array reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadArrayLen() (int64, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return 0, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return 0, ParseErrorReply(line)
+	case ArrayReply:
+		return parseArrayLen(line)
+	default:
+		return 0, fmt.Errorf("redis: can't parse array reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadScanReply() ([]string, uint64, error) {
+	n, err := r.ReadArrayLen()
+	if err != nil {
+		return nil, 0, err
+	}
+	if n != 2 {
+		return nil, 0, fmt.Errorf("redis: got %d elements in scan reply, expected 2", n)
+	}
+
+	cursor, err := r.ReadUint()
+	if err != nil {
+		return nil, 0, err
+	}
+
+	n, err = r.ReadArrayLen()
+	if err != nil {
+		return nil, 0, err
+	}
+
+	keys := make([]string, n)
+	for i := int64(0); i < n; i++ {
+		key, err := r.ReadString()
+		if err != nil {
+			return nil, 0, err
+		}
+		keys[i] = key
+	}
+
+	return keys, cursor, err
+}
+
+func (r *Reader) ReadInt() (int64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseInt(b, 10, 64)
+}
+
+func (r *Reader) ReadUint() (uint64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseUint(b, 10, 64)
+}
+
+func (r *Reader) ReadFloatReply() (float64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseFloat(b, 64)
+}
+
+func (r *Reader) readTmpBytesReply() ([]byte, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case StringReply:
+		return r._readTmpBytesReply(line)
+	case StatusReply:
+		return line[1:], nil
+	default:
+		return nil, fmt.Errorf("redis: can't parse string reply: %.100q", line)
+	}
+}
+
+func (r *Reader) _readTmpBytesReply(line []byte) ([]byte, error) {
+	if isNilReply(line) {
+		return nil, Nil
+	}
+
+	replyLen, err := strconv.Atoi(string(line[1:]))
+	if err != nil {
+		return nil, err
+	}
+
+	buf := r.buf(replyLen + 2)
+	_, err = io.ReadFull(r.rd, buf)
+	if err != nil {
+		return nil, err
+	}
+
+	return buf[:replyLen], nil
+}
+
+func (r *Reader) buf(n int) []byte {
+	if d := n - cap(r._buf); d > 0 {
+		r._buf = append(r._buf, make([]byte, d)...)
+	}
+	return r._buf[:n]
+}
+
+func isNilReply(b []byte) bool {
+	return len(b) == 3 &&
+		(b[0] == StringReply || b[0] == ArrayReply) &&
+		b[1] == '-' && b[2] == '1'
+}
+
+func ParseErrorReply(line []byte) error {
+	return RedisError(string(line[1:]))
+}
+
+func parseArrayLen(line []byte) (int64, error) {
+	if isNilReply(line) {
+		return 0, Nil
+	}
+	return util.ParseInt(line[1:], 10, 64)
+}

vendor/github.com/go-redis/redis/internal/proto/scan.go

@@ -0,0 +1,166 @@
+package proto
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+func Scan(b []byte, v interface{}) error {
+	switch v := v.(type) {
+	case nil:
+		return fmt.Errorf("redis: Scan(nil)")
+	case *string:
+		*v = util.BytesToString(b)
+		return nil
+	case *[]byte:
+		*v = b
+		return nil
+	case *int:
+		var err error
+		*v, err = util.Atoi(b)
+		return err
+	case *int8:
+		n, err := util.ParseInt(b, 10, 8)
+		if err != nil {
+			return err
+		}
+		*v = int8(n)
+		return nil
+	case *int16:
+		n, err := util.ParseInt(b, 10, 16)
+		if err != nil {
+			return err
+		}
+		*v = int16(n)
+		return nil
+	case *int32:
+		n, err := util.ParseInt(b, 10, 32)
+		if err != nil {
+			return err
+		}
+		*v = int32(n)
+		return nil
+	case *int64:
+		n, err := util.ParseInt(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = n
+		return nil
+	case *uint:
+		n, err := util.ParseUint(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = uint(n)
+		return nil
+	case *uint8:
+		n, err := util.ParseUint(b, 10, 8)
+		if err != nil {
+			return err
+		}
+		*v = uint8(n)
+		return nil
+	case *uint16:
+		n, err := util.ParseUint(b, 10, 16)
+		if err != nil {
+			return err
+		}
+		*v = uint16(n)
+		return nil
+	case *uint32:
+		n, err := util.ParseUint(b, 10, 32)
+		if err != nil {
+			return err
+		}
+		*v = uint32(n)
+		return nil
+	case *uint64:
+		n, err := util.ParseUint(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = n
+		return nil
+	case *float32:
+		n, err := util.ParseFloat(b, 32)
+		if err != nil {
+			return err
+		}
+		*v = float32(n)
+		return err
+	case *float64:
+		var err error
+		*v, err = util.ParseFloat(b, 64)
+		return err
+	case *bool:
+		*v = len(b) == 1 && b[0] == '1'
+		return nil
+	case encoding.BinaryUnmarshaler:
+		return v.UnmarshalBinary(b)
+	default:
+		return fmt.Errorf(
+			"redis: can't unmarshal %T (consider implementing BinaryUnmarshaler)", v)
+	}
+}
+
+func ScanSlice(data []string, slice interface{}) error {
+	v := reflect.ValueOf(slice)
+	if !v.IsValid() {
+		return fmt.Errorf("redis: ScanSlice(nil)")
+	}
+	if v.Kind() != reflect.Ptr {
+		return fmt.Errorf("redis: ScanSlice(non-pointer %T)", slice)
+	}
+	v = v.Elem()
+	if v.Kind() != reflect.Slice {
+		return fmt.Errorf("redis: ScanSlice(non-slice %T)", slice)
+	}
+
+	next := makeSliceNextElemFunc(v)
+	for i, s := range data {
+		elem := next()
+		if err := Scan([]byte(s), elem.Addr().Interface()); err != nil {
+			err = fmt.Errorf("redis: ScanSlice index=%d value=%q failed: %s", i, s, err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func makeSliceNextElemFunc(v reflect.Value) func() reflect.Value {
+	elemType := v.Type().Elem()
+
+	if elemType.Kind() == reflect.Ptr {
+		elemType = elemType.Elem()
+		return func() reflect.Value {
+			if v.Len() < v.Cap() {
+				v.Set(v.Slice(0, v.Len()+1))
+				elem := v.Index(v.Len() - 1)
+				if elem.IsNil() {
+					elem.Set(reflect.New(elemType))
+				}
+				return elem.Elem()
+			}
+
+			elem := reflect.New(elemType)
+			v.Set(reflect.Append(v, elem))
+			return elem.Elem()
+		}
+	}
+
+	zero := reflect.Zero(elemType)
+	return func() reflect.Value {
+		if v.Len() < v.Cap() {
+			v.Set(v.Slice(0, v.Len()+1))
+			return v.Index(v.Len() - 1)
+		}
+
+		v.Set(reflect.Append(v, zero))
+		return v.Index(v.Len() - 1)
+	}
+}

vendor/github.com/go-redis/redis/internal/proto/writer.go

@@ -0,0 +1,159 @@
+package proto
+
+import (
+	"bufio"
+	"encoding"
+	"fmt"
+	"io"
+	"strconv"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+type Writer struct {
+	wr *bufio.Writer
+
+	lenBuf []byte
+	numBuf []byte
+}
+
+func NewWriter(wr io.Writer) *Writer {
+	return &Writer{
+		wr: bufio.NewWriter(wr),
+
+		lenBuf: make([]byte, 64),
+		numBuf: make([]byte, 64),
+	}
+}
+
+func (w *Writer) WriteArgs(args []interface{}) error {
+	err := w.wr.WriteByte(ArrayReply)
+	if err != nil {
+		return err
+	}
+
+	err = w.writeLen(len(args))
+	if err != nil {
+		return err
+	}
+
+	for _, arg := range args {
+		err := w.writeArg(arg)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (w *Writer) writeLen(n int) error {
+	w.lenBuf = strconv.AppendUint(w.lenBuf[:0], uint64(n), 10)
+	w.lenBuf = append(w.lenBuf, '\r', '\n')
+	_, err := w.wr.Write(w.lenBuf)
+	return err
+}
+
+func (w *Writer) writeArg(v interface{}) error {
+	switch v := v.(type) {
+	case nil:
+		return w.string("")
+	case string:
+		return w.string(v)
+	case []byte:
+		return w.bytes(v)
+	case int:
+		return w.int(int64(v))
+	case int8:
+		return w.int(int64(v))
+	case int16:
+		return w.int(int64(v))
+	case int32:
+		return w.int(int64(v))
+	case int64:
+		return w.int(v)
+	case uint:
+		return w.uint(uint64(v))
+	case uint8:
+		return w.uint(uint64(v))
+	case uint16:
+		return w.uint(uint64(v))
+	case uint32:
+		return w.uint(uint64(v))
+	case uint64:
+		return w.uint(v)
+	case float32:
+		return w.float(float64(v))
+	case float64:
+		return w.float(v)
+	case bool:
+		if v {
+			return w.int(1)
+		} else {
+			return w.int(0)
+		}
+	case encoding.BinaryMarshaler:
+		b, err := v.MarshalBinary()
+		if err != nil {
+			return err
+		}
+		return w.bytes(b)
+	default:
+		return fmt.Errorf(
+			"redis: can't marshal %T (implement encoding.BinaryMarshaler)", v)
+	}
+}
+
+func (w *Writer) bytes(b []byte) error {
+	err := w.wr.WriteByte(StringReply)
+	if err != nil {
+		return err
+	}
+
+	err = w.writeLen(len(b))
+	if err != nil {
+		return err
+	}
+
+	_, err = w.wr.Write(b)
+	if err != nil {
+		return err
+	}
+
+	return w.crlf()
+}
+
+func (w *Writer) string(s string) error {
+	return w.bytes(util.StringToBytes(s))
+}
+
+func (w *Writer) uint(n uint64) error {
+	w.numBuf = strconv.AppendUint(w.numBuf[:0], n, 10)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) int(n int64) error {
+	w.numBuf = strconv.AppendInt(w.numBuf[:0], n, 10)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) float(f float64) error {
+	w.numBuf = strconv.AppendFloat(w.numBuf[:0], f, 'f', -1, 64)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) crlf() error {
+	err := w.wr.WriteByte('\r')
+	if err != nil {
+		return err
+	}
+	return w.wr.WriteByte('\n')
+}
+
+func (w *Writer) Reset(wr io.Writer) {
+	w.wr.Reset(wr)
+}
+
+func (w *Writer) Flush() error {
+	return w.wr.Flush()
+}

vendor/github.com/go-redis/redis/internal/singleflight/singleflight.go

@@ -0,0 +1,64 @@
+/*
+Copyright 2013 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package singleflight provides a duplicate function call suppression
+// mechanism.
+package singleflight
+
+import "sync"
+
+// call is an in-flight or completed Do call
+type call struct {
+	wg  sync.WaitGroup
+	val interface{}
+	err error
+}
+
+// Group represents a class of work and forms a namespace in which
+// units of work can be executed with duplicate suppression.
+type Group struct {
+	mu sync.Mutex       // protects m
+	m  map[string]*call // lazily initialized
+}
+
+// Do executes and returns the results of the given function, making
+// sure that only one execution is in-flight for a given key at a
+// time. If a duplicate comes in, the duplicate caller waits for the
+// original to complete and receives the same results.
+func (g *Group) Do(key string, fn func() (interface{}, error)) (interface{}, error) {
+	g.mu.Lock()
+	if g.m == nil {
+		g.m = make(map[string]*call)
+	}
+	if c, ok := g.m[key]; ok {
+		g.mu.Unlock()
+		c.wg.Wait()
+		return c.val, c.err
+	}
+	c := new(call)
+	c.wg.Add(1)
+	g.m[key] = c
+	g.mu.Unlock()
+
+	c.val, c.err = fn()
+	c.wg.Done()
+
+	g.mu.Lock()
+	delete(g.m, key)
+	g.mu.Unlock()
+
+	return c.val, c.err
+}

vendor/github.com/go-redis/redis/internal/util.go

@@ -0,0 +1,29 @@
+package internal
+
+import "github.com/go-redis/redis/internal/util"
+
+func ToLower(s string) string {
+	if isLower(s) {
+		return s
+	}
+
+	b := make([]byte, len(s))
+	for i := range b {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			c += 'a' - 'A'
+		}
+		b[i] = c
+	}
+	return util.BytesToString(b)
+}
+
+func isLower(s string) bool {
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/go-redis/redis/internal/util/safe.go

@@ -0,0 +1,11 @@
+// +build appengine
+
+package util
+
+func BytesToString(b []byte) string {
+	return string(b)
+}
+
+func StringToBytes(s string) []byte {
+	return []byte(s)
+}

vendor/github.com/go-redis/redis/internal/util/strconv.go

@@ -0,0 +1,19 @@
+package util
+
+import "strconv"
+
+func Atoi(b []byte) (int, error) {
+	return strconv.Atoi(BytesToString(b))
+}
+
+func ParseInt(b []byte, base int, bitSize int) (int64, error) {
+	return strconv.ParseInt(BytesToString(b), base, bitSize)
+}
+
+func ParseUint(b []byte, base int, bitSize int) (uint64, error) {
+	return strconv.ParseUint(BytesToString(b), base, bitSize)
+}
+
+func ParseFloat(b []byte, bitSize int) (float64, error) {
+	return strconv.ParseFloat(BytesToString(b), bitSize)
+}

vendor/github.com/go-redis/redis/internal/util/unsafe.go

@@ -0,0 +1,22 @@
+// +build !appengine
+
+package util
+
+import (
+	"unsafe"
+)
+
+// BytesToString converts byte slice to string.
+func BytesToString(b []byte) string {
+	return *(*string)(unsafe.Pointer(&b))
+}
+
+// StringToBytes converts string to byte slice.
+func StringToBytes(s string) []byte {
+	return *(*[]byte)(unsafe.Pointer(
+		&struct {
+			string
+			Cap int
+		}{s, len(s)},
+	))
+}

vendor/github.com/go-redis/redis/iterator.go

@@ -0,0 +1,73 @@
+package redis
+
+import "sync"
+
+// ScanIterator is used to incrementally iterate over a collection of elements.
+// It's safe for concurrent use by multiple goroutines.
+type ScanIterator struct {
+	mu  sync.Mutex // protects Scanner and pos
+	cmd *ScanCmd
+	pos int
+}
+
+// Err returns the last iterator error, if any.
+func (it *ScanIterator) Err() error {
+	it.mu.Lock()
+	err := it.cmd.Err()
+	it.mu.Unlock()
+	return err
+}
+
+// Next advances the cursor and returns true if more values can be read.
+func (it *ScanIterator) Next() bool {
+	it.mu.Lock()
+	defer it.mu.Unlock()
+
+	// Instantly return on errors.
+	if it.cmd.Err() != nil {
+		return false
+	}
+
+	// Advance cursor, check if we are still within range.
+	if it.pos < len(it.cmd.page) {
+		it.pos++
+		return true
+	}
+
+	for {
+		// Return if there is no more data to fetch.
+		if it.cmd.cursor == 0 {
+			return false
+		}
+
+		// Fetch next page.
+		if it.cmd._args[0] == "scan" {
+			it.cmd._args[1] = it.cmd.cursor
+		} else {
+			it.cmd._args[2] = it.cmd.cursor
+		}
+
+		err := it.cmd.process(it.cmd)
+		if err != nil {
+			return false
+		}
+
+		it.pos = 1
+
+		// Redis can occasionally return empty page.
+		if len(it.cmd.page) > 0 {
+			return true
+		}
+	}
+}
+
+// Val returns the key/field at the current cursor position.
+func (it *ScanIterator) Val() string {
+	var v string
+	it.mu.Lock()
+	if it.cmd.Err() == nil && it.pos > 0 && it.pos <= len(it.cmd.page) {
+		v = it.cmd.page[it.pos-1]
+	}
+	it.mu.Unlock()
+	return v
+}

vendor/github.com/go-redis/redis/options.go

@@ -0,0 +1,212 @@
+package redis
+
+import (
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"runtime"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/go-redis/redis/internal/pool"
+)
+
+type Options struct {
+	// The network type, either tcp or unix.
+	// Default is tcp.
+	Network string
+	// host:port address.
+	Addr string
+
+	// Dialer creates new network connection and has priority over
+	// Network and Addr options.
+	Dialer func() (net.Conn, error)
+
+	// Hook that is called when new connection is established.
+	OnConnect func(*Conn) error
+
+	// Optional password. Must match the password specified in the
+	// requirepass server configuration option.
+	Password string
+	// Database to be selected after connecting to the server.
+	DB int
+
+	// Maximum number of retries before giving up.
+	// Default is to not retry failed commands.
+	MaxRetries int
+	// Minimum backoff between each retry.
+	// Default is 8 milliseconds; -1 disables backoff.
+	MinRetryBackoff time.Duration
+	// Maximum backoff between each retry.
+	// Default is 512 milliseconds; -1 disables backoff.
+	MaxRetryBackoff time.Duration
+
+	// Dial timeout for establishing new connections.
+	// Default is 5 seconds.
+	DialTimeout time.Duration
+	// Timeout for socket reads. If reached, commands will fail
+	// with a timeout instead of blocking. Use value -1 for no timeout and 0 for default.
+	// Default is 3 seconds.
+	ReadTimeout time.Duration
+	// Timeout for socket writes. If reached, commands will fail
+	// with a timeout instead of blocking.
+	// Default is ReadTimeout.
+	WriteTimeout time.Duration
+
+	// Maximum number of socket connections.
+	// Default is 10 connections per every CPU as reported by runtime.NumCPU.
+	PoolSize int
+	// Minimum number of idle connections which is useful when establishing
+	// new connection is slow.
+	MinIdleConns int
+	// Connection age at which client retires (closes) the connection.
+	// Default is to not close aged connections.
+	MaxConnAge time.Duration
+	// Amount of time client waits for connection if all connections
+	// are busy before returning an error.
+	// Default is ReadTimeout + 1 second.
+	PoolTimeout time.Duration
+	// Amount of time after which client closes idle connections.
+	// Should be less than server's timeout.
+	// Default is 5 minutes. -1 disables idle timeout check.
+	IdleTimeout time.Duration
+	// Frequency of idle checks made by idle connections reaper.
+	// Default is 1 minute. -1 disables idle connections reaper,
+	// but idle connections are still discarded by the client
+	// if IdleTimeout is set.
+	IdleCheckFrequency time.Duration
+
+	// Enables read only queries on slave nodes.
+	readOnly bool
+
+	// TLS Config to use. When set TLS will be negotiated.
+	TLSConfig *tls.Config
+}
+
+func (opt *Options) init() {
+	if opt.Network == "" {
+		opt.Network = "tcp"
+	}
+	if opt.Dialer == nil {
+		opt.Dialer = func() (net.Conn, error) {
+			netDialer := &net.Dialer{
+				Timeout:   opt.DialTimeout,
+				KeepAlive: 5 * time.Minute,
+			}
+			if opt.TLSConfig == nil {
+				return netDialer.Dial(opt.Network, opt.Addr)
+			} else {
+				return tls.DialWithDialer(netDialer, opt.Network, opt.Addr, opt.TLSConfig)
+			}
+		}
+	}
+	if opt.PoolSize == 0 {
+		opt.PoolSize = 10 * runtime.NumCPU()
+	}
+	if opt.DialTimeout == 0 {
+		opt.DialTimeout = 5 * time.Second
+	}
+	switch opt.ReadTimeout {
+	case -1:
+		opt.ReadTimeout = 0
+	case 0:
+		opt.ReadTimeout = 3 * time.Second
+	}
+	switch opt.WriteTimeout {
+	case -1:
+		opt.WriteTimeout = 0
+	case 0:
+		opt.WriteTimeout = opt.ReadTimeout
+	}
+	if opt.PoolTimeout == 0 {
+		opt.PoolTimeout = opt.ReadTimeout + time.Second
+	}
+	if opt.IdleTimeout == 0 {
+		opt.IdleTimeout = 5 * time.Minute
+	}
+	if opt.IdleCheckFrequency == 0 {
+		opt.IdleCheckFrequency = time.Minute
+	}
+
+	switch opt.MinRetryBackoff {
+	case -1:
+		opt.MinRetryBackoff = 0
+	case 0:
+		opt.MinRetryBackoff = 8 * time.Millisecond
+	}
+	switch opt.MaxRetryBackoff {
+	case -1:
+		opt.MaxRetryBackoff = 0
+	case 0:
+		opt.MaxRetryBackoff = 512 * time.Millisecond
+	}
+}
+
+// ParseURL parses an URL into Options that can be used to connect to Redis.
+func ParseURL(redisURL string) (*Options, error) {
+	o := &Options{Network: "tcp"}
+	u, err := url.Parse(redisURL)
+	if err != nil {
+		return nil, err
+	}
+
+	if u.Scheme != "redis" && u.Scheme != "rediss" {
+		return nil, errors.New("invalid redis URL scheme: " + u.Scheme)
+	}
+
+	if u.User != nil {
+		if p, ok := u.User.Password(); ok {
+			o.Password = p
+		}
+	}
+
+	if len(u.Query()) > 0 {
+		return nil, errors.New("no options supported")
+	}
+
+	h, p, err := net.SplitHostPort(u.Host)
+	if err != nil {
+		h = u.Host
+	}
+	if h == "" {
+		h = "localhost"
+	}
+	if p == "" {
+		p = "6379"
+	}
+	o.Addr = net.JoinHostPort(h, p)
+
+	f := strings.FieldsFunc(u.Path, func(r rune) bool {
+		return r == '/'
+	})
+	switch len(f) {
+	case 0:
+		o.DB = 0
+	case 1:
+		if o.DB, err = strconv.Atoi(f[0]); err != nil {
+			return nil, fmt.Errorf("invalid redis database number: %q", f[0])
+		}
+	default:
+		return nil, errors.New("invalid redis URL path: " + u.Path)
+	}
+
+	if u.Scheme == "rediss" {
+		o.TLSConfig = &tls.Config{ServerName: h}
+	}
+	return o, nil
+}
+
+func newConnPool(opt *Options) *pool.ConnPool {
+	return pool.NewConnPool(&pool.Options{
+		Dialer:             opt.Dialer,
+		PoolSize:           opt.PoolSize,
+		MinIdleConns:       opt.MinIdleConns,
+		MaxConnAge:         opt.MaxConnAge,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+	})
+}

vendor/github.com/go-redis/redis/pipeline.go

@@ -0,0 +1,113 @@
+package redis
+
+import (
+	"sync"
+
+	"github.com/go-redis/redis/internal/pool"
+)
+
+type pipelineExecer func([]Cmder) error
+
+type Pipeliner interface {
+	StatefulCmdable
+	Process(cmd Cmder) error
+	Close() error
+	Discard() error
+	Exec() ([]Cmder, error)
+}
+
+var _ Pipeliner = (*Pipeline)(nil)
+
+// Pipeline implements pipelining as described in
+// http://redis.io/topics/pipelining. It's safe for concurrent use
+// by multiple goroutines.
+type Pipeline struct {
+	statefulCmdable
+
+	exec pipelineExecer
+
+	mu     sync.Mutex
+	cmds   []Cmder
+	closed bool
+}
+
+// Process queues the cmd for later execution.
+func (c *Pipeline) Process(cmd Cmder) error {
+	c.mu.Lock()
+	c.cmds = append(c.cmds, cmd)
+	c.mu.Unlock()
+	return nil
+}
+
+// Close closes the pipeline, releasing any open resources.
+func (c *Pipeline) Close() error {
+	c.mu.Lock()
+	c.discard()
+	c.closed = true
+	c.mu.Unlock()
+	return nil
+}
+
+// Discard resets the pipeline and discards queued commands.
+func (c *Pipeline) Discard() error {
+	c.mu.Lock()
+	err := c.discard()
+	c.mu.Unlock()
+	return err
+}
+
+func (c *Pipeline) discard() error {
+	if c.closed {
+		return pool.ErrClosed
+	}
+	c.cmds = c.cmds[:0]
+	return nil
+}
+
+// Exec executes all previously queued commands using one
+// client-server roundtrip.
+//
+// Exec always returns list of commands and error of the first failed
+// command if any.
+func (c *Pipeline) Exec() ([]Cmder, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return nil, pool.ErrClosed
+	}
+
+	if len(c.cmds) == 0 {
+		return nil, nil
+	}
+
+	cmds := c.cmds
+	c.cmds = nil
+
+	return cmds, c.exec(cmds)
+}
+
+func (c *Pipeline) pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	if err := fn(c); err != nil {
+		return nil, err
+	}
+	cmds, err := c.Exec()
+	_ = c.Close()
+	return cmds, err
+}
+
+func (c *Pipeline) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.pipelined(fn)
+}
+
+func (c *Pipeline) Pipeline() Pipeliner {
+	return c
+}
+
+func (c *Pipeline) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.pipelined(fn)
+}
+
+func (c *Pipeline) TxPipeline() Pipeliner {
+	return c
+}

vendor/github.com/go-redis/redis/pubsub.go

@@ -0,0 +1,473 @@
+package redis
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+var errPingTimeout = errors.New("redis: ping timeout")
+
+// PubSub implements Pub/Sub commands bas described in
+// http://redis.io/topics/pubsub. Message receiving is NOT safe
+// for concurrent use by multiple goroutines.
+//
+// PubSub automatically reconnects to Redis Server and resubscribes
+// to the channels in case of network errors.
+type PubSub struct {
+	opt *Options
+
+	newConn   func([]string) (*pool.Conn, error)
+	closeConn func(*pool.Conn) error
+
+	mu       sync.Mutex
+	cn       *pool.Conn
+	channels map[string]struct{}
+	patterns map[string]struct{}
+	closed   bool
+	exit     chan struct{}
+
+	cmd *Cmd
+
+	chOnce sync.Once
+	ch     chan *Message
+	ping   chan struct{}
+}
+
+func (c *PubSub) init() {
+	c.exit = make(chan struct{})
+}
+
+func (c *PubSub) conn() (*pool.Conn, error) {
+	c.mu.Lock()
+	cn, err := c._conn(nil)
+	c.mu.Unlock()
+	return cn, err
+}
+
+func (c *PubSub) _conn(newChannels []string) (*pool.Conn, error) {
+	if c.closed {
+		return nil, pool.ErrClosed
+	}
+	if c.cn != nil {
+		return c.cn, nil
+	}
+
+	channels := mapKeys(c.channels)
+	channels = append(channels, newChannels...)
+
+	cn, err := c.newConn(channels)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := c.resubscribe(cn); err != nil {
+		_ = c.closeConn(cn)
+		return nil, err
+	}
+
+	c.cn = cn
+	return cn, nil
+}
+
+func (c *PubSub) writeCmd(cn *pool.Conn, cmd Cmder) error {
+	return cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return writeCmd(wr, cmd)
+	})
+}
+
+func (c *PubSub) resubscribe(cn *pool.Conn) error {
+	var firstErr error
+
+	if len(c.channels) > 0 {
+		err := c._subscribe(cn, "subscribe", mapKeys(c.channels))
+		if err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+
+	if len(c.patterns) > 0 {
+		err := c._subscribe(cn, "psubscribe", mapKeys(c.patterns))
+		if err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+
+	return firstErr
+}
+
+func mapKeys(m map[string]struct{}) []string {
+	s := make([]string, len(m))
+	i := 0
+	for k := range m {
+		s[i] = k
+		i++
+	}
+	return s
+}
+
+func (c *PubSub) _subscribe(
+	cn *pool.Conn, redisCmd string, channels []string,
+) error {
+	args := make([]interface{}, 0, 1+len(channels))
+	args = append(args, redisCmd)
+	for _, channel := range channels {
+		args = append(args, channel)
+	}
+	cmd := NewSliceCmd(args...)
+	return c.writeCmd(cn, cmd)
+}
+
+func (c *PubSub) releaseConn(cn *pool.Conn, err error, allowTimeout bool) {
+	c.mu.Lock()
+	c._releaseConn(cn, err, allowTimeout)
+	c.mu.Unlock()
+}
+
+func (c *PubSub) _releaseConn(cn *pool.Conn, err error, allowTimeout bool) {
+	if c.cn != cn {
+		return
+	}
+	if internal.IsBadConn(err, allowTimeout) {
+		c._reconnect(err)
+	}
+}
+
+func (c *PubSub) _reconnect(reason error) {
+	_ = c._closeTheCn(reason)
+	_, _ = c._conn(nil)
+}
+
+func (c *PubSub) _closeTheCn(reason error) error {
+	if c.cn == nil {
+		return nil
+	}
+	if !c.closed {
+		internal.Logf("redis: discarding bad PubSub connection: %s", reason)
+	}
+	err := c.closeConn(c.cn)
+	c.cn = nil
+	return err
+}
+
+func (c *PubSub) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return pool.ErrClosed
+	}
+	c.closed = true
+	close(c.exit)
+
+	err := c._closeTheCn(pool.ErrClosed)
+	return err
+}
+
+// Subscribe the client to the specified channels. It returns
+// empty subscription if there are no channels.
+func (c *PubSub) Subscribe(channels ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	err := c.subscribe("subscribe", channels...)
+	if c.channels == nil {
+		c.channels = make(map[string]struct{})
+	}
+	for _, s := range channels {
+		c.channels[s] = struct{}{}
+	}
+	return err
+}
+
+// PSubscribe the client to the given patterns. It returns
+// empty subscription if there are no patterns.
+func (c *PubSub) PSubscribe(patterns ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	err := c.subscribe("psubscribe", patterns...)
+	if c.patterns == nil {
+		c.patterns = make(map[string]struct{})
+	}
+	for _, s := range patterns {
+		c.patterns[s] = struct{}{}
+	}
+	return err
+}
+
+// Unsubscribe the client from the given channels, or from all of
+// them if none is given.
+func (c *PubSub) Unsubscribe(channels ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for _, channel := range channels {
+		delete(c.channels, channel)
+	}
+	err := c.subscribe("unsubscribe", channels...)
+	return err
+}
+
+// PUnsubscribe the client from the given patterns, or from all of
+// them if none is given.
+func (c *PubSub) PUnsubscribe(patterns ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for _, pattern := range patterns {
+		delete(c.patterns, pattern)
+	}
+	err := c.subscribe("punsubscribe", patterns...)
+	return err
+}
+
+func (c *PubSub) subscribe(redisCmd string, channels ...string) error {
+	cn, err := c._conn(channels)
+	if err != nil {
+		return err
+	}
+
+	err = c._subscribe(cn, redisCmd, channels)
+	c._releaseConn(cn, err, false)
+	return err
+}
+
+func (c *PubSub) Ping(payload ...string) error {
+	args := []interface{}{"ping"}
+	if len(payload) == 1 {
+		args = append(args, payload[0])
+	}
+	cmd := NewCmd(args...)
+
+	cn, err := c.conn()
+	if err != nil {
+		return err
+	}
+
+	err = c.writeCmd(cn, cmd)
+	c.releaseConn(cn, err, false)
+	return err
+}
+
+// Subscription received after a successful subscription to channel.
+type Subscription struct {
+	// Can be "subscribe", "unsubscribe", "psubscribe" or "punsubscribe".
+	Kind string
+	// Channel name we have subscribed to.
+	Channel string
+	// Number of channels we are currently subscribed to.
+	Count int
+}
+
+func (m *Subscription) String() string {
+	return fmt.Sprintf("%s: %s", m.Kind, m.Channel)
+}
+
+// Message received as result of a PUBLISH command issued by another client.
+type Message struct {
+	Channel string
+	Pattern string
+	Payload string
+}
+
+func (m *Message) String() string {
+	return fmt.Sprintf("Message<%s: %s>", m.Channel, m.Payload)
+}
+
+// Pong received as result of a PING command issued by another client.
+type Pong struct {
+	Payload string
+}
+
+func (p *Pong) String() string {
+	if p.Payload != "" {
+		return fmt.Sprintf("Pong<%s>", p.Payload)
+	}
+	return "Pong"
+}
+
+func (c *PubSub) newMessage(reply interface{}) (interface{}, error) {
+	switch reply := reply.(type) {
+	case string:
+		return &Pong{
+			Payload: reply,
+		}, nil
+	case []interface{}:
+		switch kind := reply[0].(string); kind {
+		case "subscribe", "unsubscribe", "psubscribe", "punsubscribe":
+			return &Subscription{
+				Kind:    kind,
+				Channel: reply[1].(string),
+				Count:   int(reply[2].(int64)),
+			}, nil
+		case "message":
+			return &Message{
+				Channel: reply[1].(string),
+				Payload: reply[2].(string),
+			}, nil
+		case "pmessage":
+			return &Message{
+				Pattern: reply[1].(string),
+				Channel: reply[2].(string),
+				Payload: reply[3].(string),
+			}, nil
+		case "pong":
+			return &Pong{
+				Payload: reply[1].(string),
+			}, nil
+		default:
+			return nil, fmt.Errorf("redis: unsupported pubsub message: %q", kind)
+		}
+	default:
+		return nil, fmt.Errorf("redis: unsupported pubsub message: %#v", reply)
+	}
+}
+
+// ReceiveTimeout acts like Receive but returns an error if message
+// is not received in time. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) ReceiveTimeout(timeout time.Duration) (interface{}, error) {
+	if c.cmd == nil {
+		c.cmd = NewCmd()
+	}
+
+	cn, err := c.conn()
+	if err != nil {
+		return nil, err
+	}
+
+	err = cn.WithReader(timeout, func(rd *proto.Reader) error {
+		return c.cmd.readReply(rd)
+	})
+
+	c.releaseConn(cn, err, timeout > 0)
+	if err != nil {
+		return nil, err
+	}
+
+	return c.newMessage(c.cmd.Val())
+}
+
+// Receive returns a message as a Subscription, Message, Pong or error.
+// See PubSub example for details. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) Receive() (interface{}, error) {
+	return c.ReceiveTimeout(0)
+}
+
+// ReceiveMessage returns a Message or error ignoring Subscription and Pong
+// messages. This is low-level API and in most cases Channel should be used
+// instead.
+func (c *PubSub) ReceiveMessage() (*Message, error) {
+	for {
+		msg, err := c.Receive()
+		if err != nil {
+			return nil, err
+		}
+
+		switch msg := msg.(type) {
+		case *Subscription:
+			// Ignore.
+		case *Pong:
+			// Ignore.
+		case *Message:
+			return msg, nil
+		default:
+			err := fmt.Errorf("redis: unknown message: %T", msg)
+			return nil, err
+		}
+	}
+}
+
+// Channel returns a Go channel for concurrently receiving messages.
+// It periodically sends Ping messages to test connection health.
+// The channel is closed with PubSub. Receive* APIs can not be used
+// after channel is created.
+func (c *PubSub) Channel() <-chan *Message {
+	c.chOnce.Do(c.initChannel)
+	return c.ch
+}
+
+func (c *PubSub) initChannel() {
+	c.ch = make(chan *Message, 100)
+	c.ping = make(chan struct{}, 10)
+
+	go func() {
+		var errCount int
+		for {
+			msg, err := c.Receive()
+			if err != nil {
+				if err == pool.ErrClosed {
+					close(c.ch)
+					return
+				}
+				if errCount > 0 {
+					time.Sleep(c.retryBackoff(errCount))
+				}
+				errCount++
+				continue
+			}
+			errCount = 0
+
+			// Any message is as good as a ping.
+			select {
+			case c.ping <- struct{}{}:
+			default:
+			}
+
+			switch msg := msg.(type) {
+			case *Subscription:
+				// Ignore.
+			case *Pong:
+				// Ignore.
+			case *Message:
+				c.ch <- msg
+			default:
+				internal.Logf("redis: unknown message: %T", msg)
+			}
+		}
+	}()
+
+	go func() {
+		const timeout = 5 * time.Second
+
+		timer := time.NewTimer(timeout)
+		timer.Stop()
+
+		healthy := true
+		for {
+			timer.Reset(timeout)
+			select {
+			case <-c.ping:
+				healthy = true
+				if !timer.Stop() {
+					<-timer.C
+				}
+			case <-timer.C:
+				pingErr := c.Ping()
+				if healthy {
+					healthy = false
+				} else {
+					if pingErr == nil {
+						pingErr = errPingTimeout
+					}
+					c.mu.Lock()
+					c._reconnect(pingErr)
+					c.mu.Unlock()
+				}
+			case <-c.exit:
+				return
+			}
+		}
+	}()
+}
+
+func (c *PubSub) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}

vendor/github.com/go-redis/redis/redis.go

@@ -0,0 +1,524 @@
+package redis
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+// Nil reply Redis returns when key does not exist.
+const Nil = proto.Nil
+
+func init() {
+	SetLogger(log.New(os.Stderr, "redis: ", log.LstdFlags|log.Lshortfile))
+}
+
+func SetLogger(logger *log.Logger) {
+	internal.Logger = logger
+}
+
+type baseClient struct {
+	opt      *Options
+	connPool pool.Pooler
+
+	process           func(Cmder) error
+	processPipeline   func([]Cmder) error
+	processTxPipeline func([]Cmder) error
+
+	onClose func() error // hook called when client is closed
+}
+
+func (c *baseClient) init() {
+	c.process = c.defaultProcess
+	c.processPipeline = c.defaultProcessPipeline
+	c.processTxPipeline = c.defaultProcessTxPipeline
+}
+
+func (c *baseClient) String() string {
+	return fmt.Sprintf("Redis<%s db:%d>", c.getAddr(), c.opt.DB)
+}
+
+func (c *baseClient) newConn() (*pool.Conn, error) {
+	cn, err := c.connPool.NewConn()
+	if err != nil {
+		return nil, err
+	}
+
+	if cn.InitedAt.IsZero() {
+		if err := c.initConn(cn); err != nil {
+			_ = c.connPool.CloseConn(cn)
+			return nil, err
+		}
+	}
+
+	return cn, nil
+}
+
+func (c *baseClient) getConn() (*pool.Conn, error) {
+	cn, err := c.connPool.Get()
+	if err != nil {
+		return nil, err
+	}
+
+	if cn.InitedAt.IsZero() {
+		err := c.initConn(cn)
+		if err != nil {
+			c.connPool.Remove(cn)
+			return nil, err
+		}
+	}
+
+	return cn, nil
+}
+
+func (c *baseClient) releaseConn(cn *pool.Conn, err error) {
+	if internal.IsBadConn(err, false) {
+		c.connPool.Remove(cn)
+	} else {
+		c.connPool.Put(cn)
+	}
+}
+
+func (c *baseClient) releaseConnStrict(cn *pool.Conn, err error) {
+	if err == nil || internal.IsRedisError(err) {
+		c.connPool.Put(cn)
+	} else {
+		c.connPool.Remove(cn)
+	}
+}
+
+func (c *baseClient) initConn(cn *pool.Conn) error {
+	cn.InitedAt = time.Now()
+
+	if c.opt.Password == "" &&
+		c.opt.DB == 0 &&
+		!c.opt.readOnly &&
+		c.opt.OnConnect == nil {
+		return nil
+	}
+
+	conn := newConn(c.opt, cn)
+	_, err := conn.Pipelined(func(pipe Pipeliner) error {
+		if c.opt.Password != "" {
+			pipe.Auth(c.opt.Password)
+		}
+
+		if c.opt.DB > 0 {
+			pipe.Select(c.opt.DB)
+		}
+
+		if c.opt.readOnly {
+			pipe.ReadOnly()
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	if c.opt.OnConnect != nil {
+		return c.opt.OnConnect(conn)
+	}
+	return nil
+}
+
+// Do creates a Cmd from the args and processes the cmd.
+func (c *baseClient) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+// WrapProcess wraps function that processes Redis commands.
+func (c *baseClient) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
+	c.process = fn(c.process)
+}
+
+func (c *baseClient) Process(cmd Cmder) error {
+	return c.process(cmd)
+}
+
+func (c *baseClient) defaultProcess(cmd Cmder) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		cn, err := c.getConn()
+		if err != nil {
+			cmd.setErr(err)
+			if internal.IsRetryableError(err, true) {
+				continue
+			}
+			return err
+		}
+
+		err = cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+			return writeCmd(wr, cmd)
+		})
+		if err != nil {
+			c.releaseConn(cn, err)
+			cmd.setErr(err)
+			if internal.IsRetryableError(err, true) {
+				continue
+			}
+			return err
+		}
+
+		err = cn.WithReader(c.cmdTimeout(cmd), func(rd *proto.Reader) error {
+			return cmd.readReply(rd)
+		})
+		c.releaseConn(cn, err)
+		if err != nil && internal.IsRetryableError(err, cmd.readTimeout() == nil) {
+			continue
+		}
+
+		return err
+	}
+
+	return cmd.Err()
+}
+
+func (c *baseClient) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}
+
+func (c *baseClient) cmdTimeout(cmd Cmder) time.Duration {
+	if timeout := cmd.readTimeout(); timeout != nil {
+		t := *timeout
+		if t == 0 {
+			return 0
+		}
+		return t + 10*time.Second
+	}
+	return c.opt.ReadTimeout
+}
+
+// Close closes the client, releasing any open resources.
+//
+// It is rare to Close a Client, as the Client is meant to be
+// long-lived and shared between many goroutines.
+func (c *baseClient) Close() error {
+	var firstErr error
+	if c.onClose != nil {
+		if err := c.onClose(); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	if err := c.connPool.Close(); err != nil && firstErr == nil {
+		firstErr = err
+	}
+	return firstErr
+}
+
+func (c *baseClient) getAddr() string {
+	return c.opt.Addr
+}
+
+func (c *baseClient) WrapProcessPipeline(
+	fn func(oldProcess func([]Cmder) error) func([]Cmder) error,
+) {
+	c.processPipeline = fn(c.processPipeline)
+	c.processTxPipeline = fn(c.processTxPipeline)
+}
+
+func (c *baseClient) defaultProcessPipeline(cmds []Cmder) error {
+	return c.generalProcessPipeline(cmds, c.pipelineProcessCmds)
+}
+
+func (c *baseClient) defaultProcessTxPipeline(cmds []Cmder) error {
+	return c.generalProcessPipeline(cmds, c.txPipelineProcessCmds)
+}
+
+type pipelineProcessor func(*pool.Conn, []Cmder) (bool, error)
+
+func (c *baseClient) generalProcessPipeline(cmds []Cmder, p pipelineProcessor) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		cn, err := c.getConn()
+		if err != nil {
+			setCmdsErr(cmds, err)
+			return err
+		}
+
+		canRetry, err := p(cn, cmds)
+		c.releaseConnStrict(cn, err)
+
+		if !canRetry || !internal.IsRetryableError(err, true) {
+			break
+		}
+	}
+	return cmdsFirstErr(cmds)
+}
+
+func (c *baseClient) pipelineProcessCmds(cn *pool.Conn, cmds []Cmder) (bool, error) {
+	err := cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return writeCmd(wr, cmds...)
+	})
+	if err != nil {
+		setCmdsErr(cmds, err)
+		return true, err
+	}
+
+	err = cn.WithReader(c.opt.ReadTimeout, func(rd *proto.Reader) error {
+		return pipelineReadCmds(rd, cmds)
+	})
+	return true, err
+}
+
+func pipelineReadCmds(rd *proto.Reader, cmds []Cmder) error {
+	for _, cmd := range cmds {
+		err := cmd.readReply(rd)
+		if err != nil && !internal.IsRedisError(err) {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *baseClient) txPipelineProcessCmds(cn *pool.Conn, cmds []Cmder) (bool, error) {
+	err := cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return txPipelineWriteMulti(wr, cmds)
+	})
+	if err != nil {
+		setCmdsErr(cmds, err)
+		return true, err
+	}
+
+	err = cn.WithReader(c.opt.ReadTimeout, func(rd *proto.Reader) error {
+		err := txPipelineReadQueued(rd, cmds)
+		if err != nil {
+			setCmdsErr(cmds, err)
+			return err
+		}
+		return pipelineReadCmds(rd, cmds)
+	})
+	return false, err
+}
+
+func txPipelineWriteMulti(wr *proto.Writer, cmds []Cmder) error {
+	multiExec := make([]Cmder, 0, len(cmds)+2)
+	multiExec = append(multiExec, NewStatusCmd("MULTI"))
+	multiExec = append(multiExec, cmds...)
+	multiExec = append(multiExec, NewSliceCmd("EXEC"))
+	return writeCmd(wr, multiExec...)
+}
+
+func txPipelineReadQueued(rd *proto.Reader, cmds []Cmder) error {
+	// Parse queued replies.
+	var statusCmd StatusCmd
+	err := statusCmd.readReply(rd)
+	if err != nil {
+		return err
+	}
+
+	for range cmds {
+		err = statusCmd.readReply(rd)
+		if err != nil && !internal.IsRedisError(err) {
+			return err
+		}
+	}
+
+	// Parse number of replies.
+	line, err := rd.ReadLine()
+	if err != nil {
+		if err == Nil {
+			err = TxFailedErr
+		}
+		return err
+	}
+
+	switch line[0] {
+	case proto.ErrorReply:
+		return proto.ParseErrorReply(line)
+	case proto.ArrayReply:
+		// ok
+	default:
+		err := fmt.Errorf("redis: expected '*', but got line %q", line)
+		return err
+	}
+
+	return nil
+}
+
+//------------------------------------------------------------------------------
+
+// Client is a Redis client representing a pool of zero or more
+// underlying connections. It's safe for concurrent use by multiple
+// goroutines.
+type Client struct {
+	baseClient
+	cmdable
+
+	ctx context.Context
+}
+
+// NewClient returns a client to the Redis Server specified by Options.
+func NewClient(opt *Options) *Client {
+	opt.init()
+
+	c := Client{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: newConnPool(opt),
+		},
+	}
+	c.baseClient.init()
+	c.init()
+
+	return &c
+}
+
+func (c *Client) init() {
+	c.cmdable.setProcessor(c.Process)
+}
+
+func (c *Client) Context() context.Context {
+	if c.ctx != nil {
+		return c.ctx
+	}
+	return context.Background()
+}
+
+func (c *Client) WithContext(ctx context.Context) *Client {
+	if ctx == nil {
+		panic("nil context")
+	}
+	c2 := c.copy()
+	c2.ctx = ctx
+	return c2
+}
+
+func (c *Client) copy() *Client {
+	cp := *c
+	cp.init()
+	return &cp
+}
+
+// Options returns read-only Options that were used to create the client.
+func (c *Client) Options() *Options {
+	return c.opt
+}
+
+type PoolStats pool.Stats
+
+// PoolStats returns connection pool stats.
+func (c *Client) PoolStats() *PoolStats {
+	stats := c.connPool.Stats()
+	return (*PoolStats)(stats)
+}
+
+func (c *Client) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Client) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Client) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.TxPipeline().Pipelined(fn)
+}
+
+// TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
+func (c *Client) TxPipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Client) pubSub() *PubSub {
+	pubsub := &PubSub{
+		opt: c.opt,
+
+		newConn: func(channels []string) (*pool.Conn, error) {
+			return c.newConn()
+		},
+		closeConn: c.connPool.CloseConn,
+	}
+	pubsub.init()
+	return pubsub
+}
+
+// Subscribe subscribes the client to the specified channels.
+// Channels can be omitted to create empty subscription.
+func (c *Client) Subscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.Subscribe(channels...)
+	}
+	return pubsub
+}
+
+// PSubscribe subscribes the client to the given patterns.
+// Patterns can be omitted to create empty subscription.
+func (c *Client) PSubscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.PSubscribe(channels...)
+	}
+	return pubsub
+}
+
+//------------------------------------------------------------------------------
+
+// Conn is like Client, but its pool contains single connection.
+type Conn struct {
+	baseClient
+	statefulCmdable
+}
+
+func newConn(opt *Options, cn *pool.Conn) *Conn {
+	c := Conn{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: pool.NewSingleConnPool(cn),
+		},
+	}
+	c.baseClient.init()
+	c.statefulCmdable.setProcessor(c.Process)
+	return &c
+}
+
+func (c *Conn) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Conn) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Conn) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.TxPipeline().Pipelined(fn)
+}
+
+// TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
+func (c *Conn) TxPipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}

vendor/github.com/go-redis/redis/result.go

@@ -0,0 +1,140 @@
+package redis
+
+import "time"
+
+// NewCmdResult returns a Cmd initialised with val and err for testing
+func NewCmdResult(val interface{}, err error) *Cmd {
+	var cmd Cmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewSliceResult returns a SliceCmd initialised with val and err for testing
+func NewSliceResult(val []interface{}, err error) *SliceCmd {
+	var cmd SliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStatusResult returns a StatusCmd initialised with val and err for testing
+func NewStatusResult(val string, err error) *StatusCmd {
+	var cmd StatusCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewIntResult returns an IntCmd initialised with val and err for testing
+func NewIntResult(val int64, err error) *IntCmd {
+	var cmd IntCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewDurationResult returns a DurationCmd initialised with val and err for testing
+func NewDurationResult(val time.Duration, err error) *DurationCmd {
+	var cmd DurationCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewBoolResult returns a BoolCmd initialised with val and err for testing
+func NewBoolResult(val bool, err error) *BoolCmd {
+	var cmd BoolCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringResult returns a StringCmd initialised with val and err for testing
+func NewStringResult(val string, err error) *StringCmd {
+	var cmd StringCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewFloatResult returns a FloatCmd initialised with val and err for testing
+func NewFloatResult(val float64, err error) *FloatCmd {
+	var cmd FloatCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringSliceResult returns a StringSliceCmd initialised with val and err for testing
+func NewStringSliceResult(val []string, err error) *StringSliceCmd {
+	var cmd StringSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewBoolSliceResult returns a BoolSliceCmd initialised with val and err for testing
+func NewBoolSliceResult(val []bool, err error) *BoolSliceCmd {
+	var cmd BoolSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringStringMapResult returns a StringStringMapCmd initialised with val and err for testing
+func NewStringStringMapResult(val map[string]string, err error) *StringStringMapCmd {
+	var cmd StringStringMapCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringIntMapCmdResult returns a StringIntMapCmd initialised with val and err for testing
+func NewStringIntMapCmdResult(val map[string]int64, err error) *StringIntMapCmd {
+	var cmd StringIntMapCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewZSliceCmdResult returns a ZSliceCmd initialised with val and err for testing
+func NewZSliceCmdResult(val []Z, err error) *ZSliceCmd {
+	var cmd ZSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewScanCmdResult returns a ScanCmd initialised with val and err for testing
+func NewScanCmdResult(keys []string, cursor uint64, err error) *ScanCmd {
+	var cmd ScanCmd
+	cmd.page = keys
+	cmd.cursor = cursor
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewClusterSlotsCmdResult returns a ClusterSlotsCmd initialised with val and err for testing
+func NewClusterSlotsCmdResult(val []ClusterSlot, err error) *ClusterSlotsCmd {
+	var cmd ClusterSlotsCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewGeoLocationCmdResult returns a GeoLocationCmd initialised with val and err for testing
+func NewGeoLocationCmdResult(val []GeoLocation, err error) *GeoLocationCmd {
+	var cmd GeoLocationCmd
+	cmd.locations = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewCommandsInfoCmdResult returns a CommandsInfoCmd initialised with val and err for testing
+func NewCommandsInfoCmdResult(val map[string]*CommandInfo, err error) *CommandsInfoCmd {
+	var cmd CommandsInfoCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}

vendor/github.com/go-redis/redis/ring.go

@@ -0,0 +1,658 @@
+package redis
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"math/rand"
+	"strconv"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/consistenthash"
+	"github.com/go-redis/redis/internal/hashtag"
+	"github.com/go-redis/redis/internal/pool"
+)
+
+// Hash is type of hash function used in consistent hash.
+type Hash consistenthash.Hash
+
+var errRingShardsDown = errors.New("redis: all ring shards are down")
+
+// RingOptions are used to configure a ring client and should be
+// passed to NewRing.
+type RingOptions struct {
+	// Map of name => host:port addresses of ring shards.
+	Addrs map[string]string
+
+	// Frequency of PING commands sent to check shards availability.
+	// Shard is considered down after 3 subsequent failed checks.
+	HeartbeatFrequency time.Duration
+
+	// Hash function used in consistent hash.
+	// Default is crc32.ChecksumIEEE.
+	Hash Hash
+
+	// Number of replicas in consistent hash.
+	// Default is 100 replicas.
+	//
+	// Higher number of replicas will provide less deviation, that is keys will be
+	// distributed to nodes more evenly.
+	//
+	// Following is deviation for common nreplicas:
+	//  --------------------------------------------------------
+	//  | nreplicas | standard error | 99% confidence interval |
+	//  |     10    |     0.3152     |      (0.37, 1.98)       |
+	//  |    100    |     0.0997     |      (0.76, 1.28)       |
+	//  |   1000    |     0.0316     |      (0.92, 1.09)       |
+	//  --------------------------------------------------------
+	//
+	//  See https://arxiv.org/abs/1406.2294 for reference
+	HashReplicas int
+
+	// Following options are copied from Options struct.
+
+	OnConnect func(*Conn) error
+
+	DB       int
+	Password string
+
+	MaxRetries      int
+	MinRetryBackoff time.Duration
+	MaxRetryBackoff time.Duration
+
+	DialTimeout  time.Duration
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+}
+
+func (opt *RingOptions) init() {
+	if opt.HeartbeatFrequency == 0 {
+		opt.HeartbeatFrequency = 500 * time.Millisecond
+	}
+
+	if opt.HashReplicas == 0 {
+		opt.HashReplicas = 100
+	}
+
+	switch opt.MinRetryBackoff {
+	case -1:
+		opt.MinRetryBackoff = 0
+	case 0:
+		opt.MinRetryBackoff = 8 * time.Millisecond
+	}
+	switch opt.MaxRetryBackoff {
+	case -1:
+		opt.MaxRetryBackoff = 0
+	case 0:
+		opt.MaxRetryBackoff = 512 * time.Millisecond
+	}
+}
+
+func (opt *RingOptions) clientOptions() *Options {
+	return &Options{
+		OnConnect: opt.OnConnect,
+
+		DB:       opt.DB,
+		Password: opt.Password,
+
+		DialTimeout:  opt.DialTimeout,
+		ReadTimeout:  opt.ReadTimeout,
+		WriteTimeout: opt.WriteTimeout,
+
+		PoolSize:           opt.PoolSize,
+		MinIdleConns:       opt.MinIdleConns,
+		MaxConnAge:         opt.MaxConnAge,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+	}
+}
+
+//------------------------------------------------------------------------------
+
+type ringShard struct {
+	Client *Client
+	down   int32
+}
+
+func (shard *ringShard) String() string {
+	var state string
+	if shard.IsUp() {
+		state = "up"
+	} else {
+		state = "down"
+	}
+	return fmt.Sprintf("%s is %s", shard.Client, state)
+}
+
+func (shard *ringShard) IsDown() bool {
+	const threshold = 3
+	return atomic.LoadInt32(&shard.down) >= threshold
+}
+
+func (shard *ringShard) IsUp() bool {
+	return !shard.IsDown()
+}
+
+// Vote votes to set shard state and returns true if state was changed.
+func (shard *ringShard) Vote(up bool) bool {
+	if up {
+		changed := shard.IsDown()
+		atomic.StoreInt32(&shard.down, 0)
+		return changed
+	}
+
+	if shard.IsDown() {
+		return false
+	}
+
+	atomic.AddInt32(&shard.down, 1)
+	return shard.IsDown()
+}
+
+//------------------------------------------------------------------------------
+
+type ringShards struct {
+	opt *RingOptions
+
+	mu     sync.RWMutex
+	hash   *consistenthash.Map
+	shards map[string]*ringShard // read only
+	list   []*ringShard          // read only
+	len    int
+	closed bool
+}
+
+func newRingShards(opt *RingOptions) *ringShards {
+	return &ringShards{
+		opt: opt,
+
+		hash:   newConsistentHash(opt),
+		shards: make(map[string]*ringShard),
+	}
+}
+
+func (c *ringShards) Add(name string, cl *Client) {
+	shard := &ringShard{Client: cl}
+	c.hash.Add(name)
+	c.shards[name] = shard
+	c.list = append(c.list, shard)
+}
+
+func (c *ringShards) List() []*ringShard {
+	c.mu.RLock()
+	list := c.list
+	c.mu.RUnlock()
+	return list
+}
+
+func (c *ringShards) Hash(key string) string {
+	c.mu.RLock()
+	hash := c.hash.Get(key)
+	c.mu.RUnlock()
+	return hash
+}
+
+func (c *ringShards) GetByKey(key string) (*ringShard, error) {
+	key = hashtag.Key(key)
+
+	c.mu.RLock()
+
+	if c.closed {
+		c.mu.RUnlock()
+		return nil, pool.ErrClosed
+	}
+
+	hash := c.hash.Get(key)
+	if hash == "" {
+		c.mu.RUnlock()
+		return nil, errRingShardsDown
+	}
+
+	shard := c.shards[hash]
+	c.mu.RUnlock()
+
+	return shard, nil
+}
+
+func (c *ringShards) GetByHash(name string) (*ringShard, error) {
+	if name == "" {
+		return c.Random()
+	}
+
+	c.mu.RLock()
+	shard := c.shards[name]
+	c.mu.RUnlock()
+	return shard, nil
+}
+
+func (c *ringShards) Random() (*ringShard, error) {
+	return c.GetByKey(strconv.Itoa(rand.Int()))
+}
+
+// heartbeat monitors state of each shard in the ring.
+func (c *ringShards) Heartbeat(frequency time.Duration) {
+	ticker := time.NewTicker(frequency)
+	defer ticker.Stop()
+	for range ticker.C {
+		var rebalance bool
+
+		c.mu.RLock()
+
+		if c.closed {
+			c.mu.RUnlock()
+			break
+		}
+
+		shards := c.list
+		c.mu.RUnlock()
+
+		for _, shard := range shards {
+			err := shard.Client.Ping().Err()
+			if shard.Vote(err == nil || err == pool.ErrPoolTimeout) {
+				internal.Logf("ring shard state changed: %s", shard)
+				rebalance = true
+			}
+		}
+
+		if rebalance {
+			c.rebalance()
+		}
+	}
+}
+
+// rebalance removes dead shards from the Ring.
+func (c *ringShards) rebalance() {
+	hash := newConsistentHash(c.opt)
+	var shardsNum int
+	for name, shard := range c.shards {
+		if shard.IsUp() {
+			hash.Add(name)
+			shardsNum++
+		}
+	}
+
+	c.mu.Lock()
+	c.hash = hash
+	c.len = shardsNum
+	c.mu.Unlock()
+}
+
+func (c *ringShards) Len() int {
+	c.mu.RLock()
+	l := c.len
+	c.mu.RUnlock()
+	return l
+}
+
+func (c *ringShards) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return nil
+	}
+	c.closed = true
+
+	var firstErr error
+	for _, shard := range c.shards {
+		if err := shard.Client.Close(); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	c.hash = nil
+	c.shards = nil
+	c.list = nil
+
+	return firstErr
+}
+
+//------------------------------------------------------------------------------
+
+// Ring is a Redis client that uses constistent hashing to distribute
+// keys across multiple Redis servers (shards). It's safe for
+// concurrent use by multiple goroutines.
+//
+// Ring monitors the state of each shard and removes dead shards from
+// the ring. When shard comes online it is added back to the ring. This
+// gives you maximum availability and partition tolerance, but no
+// consistency between different shards or even clients. Each client
+// uses shards that are available to the client and does not do any
+// coordination when shard state is changed.
+//
+// Ring should be used when you need multiple Redis servers for caching
+// and can tolerate losing data when one of the servers dies.
+// Otherwise you should use Redis Cluster.
+type Ring struct {
+	cmdable
+
+	ctx context.Context
+
+	opt           *RingOptions
+	shards        *ringShards
+	cmdsInfoCache *cmdsInfoCache
+
+	process         func(Cmder) error
+	processPipeline func([]Cmder) error
+}
+
+func NewRing(opt *RingOptions) *Ring {
+	opt.init()
+
+	ring := &Ring{
+		opt:    opt,
+		shards: newRingShards(opt),
+	}
+	ring.cmdsInfoCache = newCmdsInfoCache(ring.cmdsInfo)
+
+	ring.process = ring.defaultProcess
+	ring.processPipeline = ring.defaultProcessPipeline
+	ring.cmdable.setProcessor(ring.Process)
+
+	for name, addr := range opt.Addrs {
+		clopt := opt.clientOptions()
+		clopt.Addr = addr
+		ring.shards.Add(name, NewClient(clopt))
+	}
+
+	go ring.shards.Heartbeat(opt.HeartbeatFrequency)
+
+	return ring
+}
+
+func (c *Ring) Context() context.Context {
+	if c.ctx != nil {
+		return c.ctx
+	}
+	return context.Background()
+}
+
+func (c *Ring) WithContext(ctx context.Context) *Ring {
+	if ctx == nil {
+		panic("nil context")
+	}
+	c2 := c.copy()
+	c2.ctx = ctx
+	return c2
+}
+
+func (c *Ring) copy() *Ring {
+	cp := *c
+	return &cp
+}
+
+// Options returns read-only Options that were used to create the client.
+func (c *Ring) Options() *RingOptions {
+	return c.opt
+}
+
+func (c *Ring) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}
+
+// PoolStats returns accumulated connection pool stats.
+func (c *Ring) PoolStats() *PoolStats {
+	shards := c.shards.List()
+	var acc PoolStats
+	for _, shard := range shards {
+		s := shard.Client.connPool.Stats()
+		acc.Hits += s.Hits
+		acc.Misses += s.Misses
+		acc.Timeouts += s.Timeouts
+		acc.TotalConns += s.TotalConns
+		acc.IdleConns += s.IdleConns
+	}
+	return &acc
+}
+
+// Len returns the current number of shards in the ring.
+func (c *Ring) Len() int {
+	return c.shards.Len()
+}
+
+// Subscribe subscribes the client to the specified channels.
+func (c *Ring) Subscribe(channels ...string) *PubSub {
+	if len(channels) == 0 {
+		panic("at least one channel is required")
+	}
+
+	shard, err := c.shards.GetByKey(channels[0])
+	if err != nil {
+		// TODO: return PubSub with sticky error
+		panic(err)
+	}
+	return shard.Client.Subscribe(channels...)
+}
+
+// PSubscribe subscribes the client to the given patterns.
+func (c *Ring) PSubscribe(channels ...string) *PubSub {
+	if len(channels) == 0 {
+		panic("at least one channel is required")
+	}
+
+	shard, err := c.shards.GetByKey(channels[0])
+	if err != nil {
+		// TODO: return PubSub with sticky error
+		panic(err)
+	}
+	return shard.Client.PSubscribe(channels...)
+}
+
+// ForEachShard concurrently calls the fn on each live shard in the ring.
+// It returns the first error if any.
+func (c *Ring) ForEachShard(fn func(client *Client) error) error {
+	shards := c.shards.List()
+	var wg sync.WaitGroup
+	errCh := make(chan error, 1)
+	for _, shard := range shards {
+		if shard.IsDown() {
+			continue
+		}
+
+		wg.Add(1)
+		go func(shard *ringShard) {
+			defer wg.Done()
+			err := fn(shard.Client)
+			if err != nil {
+				select {
+				case errCh <- err:
+				default:
+				}
+			}
+		}(shard)
+	}
+	wg.Wait()
+
+	select {
+	case err := <-errCh:
+		return err
+	default:
+		return nil
+	}
+}
+
+func (c *Ring) cmdsInfo() (map[string]*CommandInfo, error) {
+	shards := c.shards.List()
+	firstErr := errRingShardsDown
+	for _, shard := range shards {
+		cmdsInfo, err := shard.Client.Command().Result()
+		if err == nil {
+			return cmdsInfo, nil
+		}
+		if firstErr == nil {
+			firstErr = err
+		}
+	}
+	return nil, firstErr
+}
+
+func (c *Ring) cmdInfo(name string) *CommandInfo {
+	cmdsInfo, err := c.cmdsInfoCache.Get()
+	if err != nil {
+		return nil
+	}
+	info := cmdsInfo[name]
+	if info == nil {
+		internal.Logf("info for cmd=%s not found", name)
+	}
+	return info
+}
+
+func (c *Ring) cmdShard(cmd Cmder) (*ringShard, error) {
+	cmdInfo := c.cmdInfo(cmd.Name())
+	pos := cmdFirstKeyPos(cmd, cmdInfo)
+	if pos == 0 {
+		return c.shards.Random()
+	}
+	firstKey := cmd.stringArg(pos)
+	return c.shards.GetByKey(firstKey)
+}
+
+// Do creates a Cmd from the args and processes the cmd.
+func (c *Ring) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+func (c *Ring) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
+	c.process = fn(c.process)
+}
+
+func (c *Ring) Process(cmd Cmder) error {
+	return c.process(cmd)
+}
+
+func (c *Ring) defaultProcess(cmd Cmder) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		shard, err := c.cmdShard(cmd)
+		if err != nil {
+			cmd.setErr(err)
+			return err
+		}
+
+		err = shard.Client.Process(cmd)
+		if err == nil {
+			return nil
+		}
+		if !internal.IsRetryableError(err, cmd.readTimeout() == nil) {
+			return err
+		}
+	}
+	return cmd.Err()
+}
+
+func (c *Ring) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.cmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Ring) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Ring) WrapProcessPipeline(
+	fn func(oldProcess func([]Cmder) error) func([]Cmder) error,
+) {
+	c.processPipeline = fn(c.processPipeline)
+}
+
+func (c *Ring) defaultProcessPipeline(cmds []Cmder) error {
+	cmdsMap := make(map[string][]Cmder)
+	for _, cmd := range cmds {
+		cmdInfo := c.cmdInfo(cmd.Name())
+		hash := cmd.stringArg(cmdFirstKeyPos(cmd, cmdInfo))
+		if hash != "" {
+			hash = c.shards.Hash(hashtag.Key(hash))
+		}
+		cmdsMap[hash] = append(cmdsMap[hash], cmd)
+	}
+
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		var mu sync.Mutex
+		var failedCmdsMap map[string][]Cmder
+		var wg sync.WaitGroup
+
+		for hash, cmds := range cmdsMap {
+			wg.Add(1)
+			go func(hash string, cmds []Cmder) {
+				defer wg.Done()
+
+				shard, err := c.shards.GetByHash(hash)
+				if err != nil {
+					setCmdsErr(cmds, err)
+					return
+				}
+
+				cn, err := shard.Client.getConn()
+				if err != nil {
+					setCmdsErr(cmds, err)
+					return
+				}
+
+				canRetry, err := shard.Client.pipelineProcessCmds(cn, cmds)
+				shard.Client.releaseConnStrict(cn, err)
+
+				if canRetry && internal.IsRetryableError(err, true) {
+					mu.Lock()
+					if failedCmdsMap == nil {
+						failedCmdsMap = make(map[string][]Cmder)
+					}
+					failedCmdsMap[hash] = cmds
+					mu.Unlock()
+				}
+			}(hash, cmds)
+		}
+
+		wg.Wait()
+		if len(failedCmdsMap) == 0 {
+			break
+		}
+		cmdsMap = failedCmdsMap
+	}
+
+	return cmdsFirstErr(cmds)
+}
+
+func (c *Ring) TxPipeline() Pipeliner {
+	panic("not implemented")
+}
+
+func (c *Ring) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	panic("not implemented")
+}
+
+// Close closes the ring client, releasing any open resources.
+//
+// It is rare to Close a Ring, as the Ring is meant to be long-lived
+// and shared between many goroutines.
+func (c *Ring) Close() error {
+	return c.shards.Close()
+}
+
+func newConsistentHash(opt *RingOptions) *consistenthash.Map {
+	return consistenthash.New(opt.HashReplicas, consistenthash.Hash(opt.Hash))
+}

vendor/github.com/go-redis/redis/script.go

@@ -0,0 +1,62 @@
+package redis
+
+import (
+	"crypto/sha1"
+	"encoding/hex"
+	"io"
+	"strings"
+)
+
+type scripter interface {
+	Eval(script string, keys []string, args ...interface{}) *Cmd
+	EvalSha(sha1 string, keys []string, args ...interface{}) *Cmd
+	ScriptExists(hashes ...string) *BoolSliceCmd
+	ScriptLoad(script string) *StringCmd
+}
+
+var _ scripter = (*Client)(nil)
+var _ scripter = (*Ring)(nil)
+var _ scripter = (*ClusterClient)(nil)
+
+type Script struct {
+	src, hash string
+}
+
+func NewScript(src string) *Script {
+	h := sha1.New()
+	io.WriteString(h, src)
+	return &Script{
+		src:  src,
+		hash: hex.EncodeToString(h.Sum(nil)),
+	}
+}
+
+func (s *Script) Hash() string {
+	return s.hash
+}
+
+func (s *Script) Load(c scripter) *StringCmd {
+	return c.ScriptLoad(s.src)
+}
+
+func (s *Script) Exists(c scripter) *BoolSliceCmd {
+	return c.ScriptExists(s.hash)
+}
+
+func (s *Script) Eval(c scripter, keys []string, args ...interface{}) *Cmd {
+	return c.Eval(s.src, keys, args...)
+}
+
+func (s *Script) EvalSha(c scripter, keys []string, args ...interface{}) *Cmd {
+	return c.EvalSha(s.hash, keys, args...)
+}
+
+// Run optimistically uses EVALSHA to run the script. If script does not exist
+// it is retried using EVAL.
+func (s *Script) Run(c scripter, keys []string, args ...interface{}) *Cmd {
+	r := s.EvalSha(c, keys, args...)
+	if err := r.Err(); err != nil && strings.HasPrefix(err.Error(), "NOSCRIPT ") {
+		return s.Eval(c, keys, args...)
+	}
+	return r
+}

vendor/github.com/go-redis/redis/sentinel.go

@@ -0,0 +1,369 @@
+package redis
+
+import (
+	"crypto/tls"
+	"errors"
+	"net"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+)
+
+//------------------------------------------------------------------------------
+
+// FailoverOptions are used to configure a failover client and should
+// be passed to NewFailoverClient.
+type FailoverOptions struct {
+	// The master name.
+	MasterName string
+	// A seed list of host:port addresses of sentinel nodes.
+	SentinelAddrs []string
+
+	// Following options are copied from Options struct.
+
+	OnConnect func(*Conn) error
+
+	Password string
+	DB       int
+
+	MaxRetries      int
+	MinRetryBackoff time.Duration
+	MaxRetryBackoff time.Duration
+
+	DialTimeout  time.Duration
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+
+	TLSConfig *tls.Config
+}
+
+func (opt *FailoverOptions) options() *Options {
+	return &Options{
+		Addr: "FailoverClient",
+
+		OnConnect: opt.OnConnect,
+
+		DB:       opt.DB,
+		Password: opt.Password,
+
+		MaxRetries: opt.MaxRetries,
+
+		DialTimeout:  opt.DialTimeout,
+		ReadTimeout:  opt.ReadTimeout,
+		WriteTimeout: opt.WriteTimeout,
+
+		PoolSize:           opt.PoolSize,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+
+		TLSConfig: opt.TLSConfig,
+	}
+}
+
+// NewFailoverClient returns a Redis client that uses Redis Sentinel
+// for automatic failover. It's safe for concurrent use by multiple
+// goroutines.
+func NewFailoverClient(failoverOpt *FailoverOptions) *Client {
+	opt := failoverOpt.options()
+	opt.init()
+
+	failover := &sentinelFailover{
+		masterName:    failoverOpt.MasterName,
+		sentinelAddrs: failoverOpt.SentinelAddrs,
+
+		opt: opt,
+	}
+
+	c := Client{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: failover.Pool(),
+
+			onClose: func() error {
+				return failover.Close()
+			},
+		},
+	}
+	c.baseClient.init()
+	c.cmdable.setProcessor(c.Process)
+
+	return &c
+}
+
+//------------------------------------------------------------------------------
+
+type SentinelClient struct {
+	baseClient
+}
+
+func NewSentinelClient(opt *Options) *SentinelClient {
+	opt.init()
+	c := &SentinelClient{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: newConnPool(opt),
+		},
+	}
+	c.baseClient.init()
+	return c
+}
+
+func (c *SentinelClient) pubSub() *PubSub {
+	pubsub := &PubSub{
+		opt: c.opt,
+
+		newConn: func(channels []string) (*pool.Conn, error) {
+			return c.newConn()
+		},
+		closeConn: c.connPool.CloseConn,
+	}
+	pubsub.init()
+	return pubsub
+}
+
+// Subscribe subscribes the client to the specified channels.
+// Channels can be omitted to create empty subscription.
+func (c *SentinelClient) Subscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.Subscribe(channels...)
+	}
+	return pubsub
+}
+
+// PSubscribe subscribes the client to the given patterns.
+// Patterns can be omitted to create empty subscription.
+func (c *SentinelClient) PSubscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.PSubscribe(channels...)
+	}
+	return pubsub
+}
+
+func (c *SentinelClient) GetMasterAddrByName(name string) *StringSliceCmd {
+	cmd := NewStringSliceCmd("sentinel", "get-master-addr-by-name", name)
+	c.Process(cmd)
+	return cmd
+}
+
+func (c *SentinelClient) Sentinels(name string) *SliceCmd {
+	cmd := NewSliceCmd("sentinel", "sentinels", name)
+	c.Process(cmd)
+	return cmd
+}
+
+type sentinelFailover struct {
+	sentinelAddrs []string
+
+	opt *Options
+
+	pool     *pool.ConnPool
+	poolOnce sync.Once
+
+	mu          sync.RWMutex
+	masterName  string
+	_masterAddr string
+	sentinel    *SentinelClient
+}
+
+func (c *sentinelFailover) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.sentinel != nil {
+		return c.closeSentinel()
+	}
+	return nil
+}
+
+func (c *sentinelFailover) Pool() *pool.ConnPool {
+	c.poolOnce.Do(func() {
+		c.opt.Dialer = c.dial
+		c.pool = newConnPool(c.opt)
+	})
+	return c.pool
+}
+
+func (c *sentinelFailover) dial() (net.Conn, error) {
+	addr, err := c.MasterAddr()
+	if err != nil {
+		return nil, err
+	}
+	return net.DialTimeout("tcp", addr, c.opt.DialTimeout)
+}
+
+func (c *sentinelFailover) MasterAddr() (string, error) {
+	addr, err := c.masterAddr()
+	if err != nil {
+		return "", err
+	}
+	c.switchMaster(addr)
+	return addr, nil
+}
+
+func (c *sentinelFailover) masterAddr() (string, error) {
+	addr := c.getMasterAddr()
+	if addr != "" {
+		return addr, nil
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for i, sentinelAddr := range c.sentinelAddrs {
+		sentinel := NewSentinelClient(&Options{
+			Addr: sentinelAddr,
+
+			MaxRetries: c.opt.MaxRetries,
+
+			DialTimeout:  c.opt.DialTimeout,
+			ReadTimeout:  c.opt.ReadTimeout,
+			WriteTimeout: c.opt.WriteTimeout,
+
+			PoolSize:           c.opt.PoolSize,
+			PoolTimeout:        c.opt.PoolTimeout,
+			IdleTimeout:        c.opt.IdleTimeout,
+			IdleCheckFrequency: c.opt.IdleCheckFrequency,
+
+			TLSConfig: c.opt.TLSConfig,
+		})
+
+		masterAddr, err := sentinel.GetMasterAddrByName(c.masterName).Result()
+		if err != nil {
+			internal.Logf("sentinel: GetMasterAddrByName master=%q failed: %s",
+				c.masterName, err)
+			_ = sentinel.Close()
+			continue
+		}
+
+		// Push working sentinel to the top.
+		c.sentinelAddrs[0], c.sentinelAddrs[i] = c.sentinelAddrs[i], c.sentinelAddrs[0]
+		c.setSentinel(sentinel)
+
+		addr := net.JoinHostPort(masterAddr[0], masterAddr[1])
+		return addr, nil
+	}
+
+	return "", errors.New("redis: all sentinels are unreachable")
+}
+
+func (c *sentinelFailover) getMasterAddr() string {
+	c.mu.RLock()
+	sentinel := c.sentinel
+	c.mu.RUnlock()
+
+	if sentinel == nil {
+		return ""
+	}
+
+	addr, err := sentinel.GetMasterAddrByName(c.masterName).Result()
+	if err != nil {
+		internal.Logf("sentinel: GetMasterAddrByName name=%q failed: %s",
+			c.masterName, err)
+		c.mu.Lock()
+		if c.sentinel == sentinel {
+			c.closeSentinel()
+		}
+		c.mu.Unlock()
+		return ""
+	}
+
+	return net.JoinHostPort(addr[0], addr[1])
+}
+
+func (c *sentinelFailover) switchMaster(addr string) {
+	c.mu.RLock()
+	masterAddr := c._masterAddr
+	c.mu.RUnlock()
+	if masterAddr == addr {
+		return
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	internal.Logf("sentinel: new master=%q addr=%q",
+		c.masterName, addr)
+	_ = c.Pool().Filter(func(cn *pool.Conn) bool {
+		return cn.RemoteAddr().String() != addr
+	})
+	c._masterAddr = addr
+}
+
+func (c *sentinelFailover) setSentinel(sentinel *SentinelClient) {
+	c.discoverSentinels(sentinel)
+	c.sentinel = sentinel
+	go c.listen(sentinel)
+}
+
+func (c *sentinelFailover) closeSentinel() error {
+	err := c.sentinel.Close()
+	c.sentinel = nil
+	return err
+}
+
+func (c *sentinelFailover) discoverSentinels(sentinel *SentinelClient) {
+	sentinels, err := sentinel.Sentinels(c.masterName).Result()
+	if err != nil {
+		internal.Logf("sentinel: Sentinels master=%q failed: %s", c.masterName, err)
+		return
+	}
+	for _, sentinel := range sentinels {
+		vals := sentinel.([]interface{})
+		for i := 0; i < len(vals); i += 2 {
+			key := vals[i].(string)
+			if key == "name" {
+				sentinelAddr := vals[i+1].(string)
+				if !contains(c.sentinelAddrs, sentinelAddr) {
+					internal.Logf("sentinel: discovered new sentinel=%q for master=%q",
+						sentinelAddr, c.masterName)
+					c.sentinelAddrs = append(c.sentinelAddrs, sentinelAddr)
+				}
+			}
+		}
+	}
+}
+
+func (c *sentinelFailover) listen(sentinel *SentinelClient) {
+	pubsub := sentinel.Subscribe("+switch-master")
+	defer pubsub.Close()
+
+	ch := pubsub.Channel()
+	for {
+		msg, ok := <-ch
+		if !ok {
+			break
+		}
+
+		switch msg.Channel {
+		case "+switch-master":
+			parts := strings.Split(msg.Payload, " ")
+			if parts[0] != c.masterName {
+				internal.Logf("sentinel: ignore addr for master=%q", parts[0])
+				continue
+			}
+			addr := net.JoinHostPort(parts[3], parts[4])
+			c.switchMaster(addr)
+		}
+	}
+}
+
+func contains(slice []string, str string) bool {
+	for _, s := range slice {
+		if s == str {
+			return true
+		}
+	}
+	return false
+}

vendor/github.com/go-redis/redis/tx.go

@@ -0,0 +1,110 @@
+package redis
+
+import (
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+// TxFailedErr transaction redis failed.
+const TxFailedErr = proto.RedisError("redis: transaction failed")
+
+// Tx implements Redis transactions as described in
+// http://redis.io/topics/transactions. It's NOT safe for concurrent use
+// by multiple goroutines, because Exec resets list of watched keys.
+// If you don't need WATCH it is better to use Pipeline.
+type Tx struct {
+	statefulCmdable
+	baseClient
+}
+
+func (c *Client) newTx() *Tx {
+	tx := Tx{
+		baseClient: baseClient{
+			opt:      c.opt,
+			connPool: pool.NewStickyConnPool(c.connPool.(*pool.ConnPool), true),
+		},
+	}
+	tx.baseClient.init()
+	tx.statefulCmdable.setProcessor(tx.Process)
+	return &tx
+}
+
+// Watch prepares a transcaction and marks the keys to be watched
+// for conditional execution if there are any keys.
+//
+// The transaction is automatically closed when the fn exits.
+func (c *Client) Watch(fn func(*Tx) error, keys ...string) error {
+	tx := c.newTx()
+	if len(keys) > 0 {
+		if err := tx.Watch(keys...).Err(); err != nil {
+			_ = tx.Close()
+			return err
+		}
+	}
+
+	err := fn(tx)
+	_ = tx.Close()
+	return err
+}
+
+// Close closes the transaction, releasing any open resources.
+func (c *Tx) Close() error {
+	_ = c.Unwatch().Err()
+	return c.baseClient.Close()
+}
+
+// Watch marks the keys to be watched for conditional execution
+// of a transaction.
+func (c *Tx) Watch(keys ...string) *StatusCmd {
+	args := make([]interface{}, 1+len(keys))
+	args[0] = "watch"
+	for i, key := range keys {
+		args[1+i] = key
+	}
+	cmd := NewStatusCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+// Unwatch flushes all the previously watched keys for a transaction.
+func (c *Tx) Unwatch(keys ...string) *StatusCmd {
+	args := make([]interface{}, 1+len(keys))
+	args[0] = "unwatch"
+	for i, key := range keys {
+		args[1+i] = key
+	}
+	cmd := NewStatusCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+// Pipeline creates a new pipeline. It is more convenient to use Pipelined.
+func (c *Tx) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+// Pipelined executes commands queued in the fn in a transaction.
+//
+// When using WATCH, EXEC will execute commands only if the watched keys
+// were not modified, allowing for a check-and-set mechanism.
+//
+// Exec always returns list of commands. If transaction fails
+// TxFailedErr is returned. Otherwise Exec returns an error of the first
+// failed command or nil.
+func (c *Tx) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+// TxPipelined is an alias for Pipelined.
+func (c *Tx) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipelined(fn)
+}
+
+// TxPipeline is an alias for Pipeline.
+func (c *Tx) TxPipeline() Pipeliner {
+	return c.Pipeline()
+}

vendor/github.com/go-redis/redis/universal.go

@@ -0,0 +1,179 @@
+package redis
+
+import (
+	"crypto/tls"
+	"time"
+)
+
+// UniversalOptions information is required by UniversalClient to establish
+// connections.
+type UniversalOptions struct {
+	// Either a single address or a seed list of host:port addresses
+	// of cluster/sentinel nodes.
+	Addrs []string
+
+	// Database to be selected after connecting to the server.
+	// Only single-node and failover clients.
+	DB int
+
+	// Common options.
+
+	OnConnect          func(*Conn) error
+	Password           string
+	MaxRetries         int
+	MinRetryBackoff    time.Duration
+	MaxRetryBackoff    time.Duration
+	DialTimeout        time.Duration
+	ReadTimeout        time.Duration
+	WriteTimeout       time.Duration
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+	TLSConfig          *tls.Config
+
+	// Only cluster clients.
+
+	MaxRedirects   int
+	ReadOnly       bool
+	RouteByLatency bool
+	RouteRandomly  bool
+
+	// The sentinel master name.
+	// Only failover clients.
+	MasterName string
+}
+
+func (o *UniversalOptions) cluster() *ClusterOptions {
+	if len(o.Addrs) == 0 {
+		o.Addrs = []string{"127.0.0.1:6379"}
+	}
+
+	return &ClusterOptions{
+		Addrs:     o.Addrs,
+		OnConnect: o.OnConnect,
+
+		Password: o.Password,
+
+		MaxRedirects:   o.MaxRedirects,
+		ReadOnly:       o.ReadOnly,
+		RouteByLatency: o.RouteByLatency,
+		RouteRandomly:  o.RouteRandomly,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:        o.DialTimeout,
+		ReadTimeout:        o.ReadTimeout,
+		WriteTimeout:       o.WriteTimeout,
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+func (o *UniversalOptions) failover() *FailoverOptions {
+	if len(o.Addrs) == 0 {
+		o.Addrs = []string{"127.0.0.1:26379"}
+	}
+
+	return &FailoverOptions{
+		SentinelAddrs: o.Addrs,
+		MasterName:    o.MasterName,
+		OnConnect:     o.OnConnect,
+
+		DB:       o.DB,
+		Password: o.Password,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:  o.DialTimeout,
+		ReadTimeout:  o.ReadTimeout,
+		WriteTimeout: o.WriteTimeout,
+
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+func (o *UniversalOptions) simple() *Options {
+	addr := "127.0.0.1:6379"
+	if len(o.Addrs) > 0 {
+		addr = o.Addrs[0]
+	}
+
+	return &Options{
+		Addr:      addr,
+		OnConnect: o.OnConnect,
+
+		DB:       o.DB,
+		Password: o.Password,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:  o.DialTimeout,
+		ReadTimeout:  o.ReadTimeout,
+		WriteTimeout: o.WriteTimeout,
+
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+// --------------------------------------------------------------------
+
+// UniversalClient is an abstract client which - based on the provided options -
+// can connect to either clusters, or sentinel-backed failover instances or simple
+// single-instance servers. This can be useful for testing cluster-specific
+// applications locally.
+type UniversalClient interface {
+	Cmdable
+	Watch(fn func(*Tx) error, keys ...string) error
+	Process(cmd Cmder) error
+	WrapProcess(fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error)
+	Subscribe(channels ...string) *PubSub
+	PSubscribe(channels ...string) *PubSub
+	Close() error
+}
+
+var _ UniversalClient = (*Client)(nil)
+var _ UniversalClient = (*ClusterClient)(nil)
+
+// NewUniversalClient returns a new multi client. The type of client returned depends
+// on the following three conditions:
+//
+// 1. if a MasterName is passed a sentinel-backed FailoverClient will be returned
+// 2. if the number of Addrs is two or more, a ClusterClient will be returned
+// 3. otherwise, a single-node redis Client will be returned.
+func NewUniversalClient(opts *UniversalOptions) UniversalClient {
+	if opts.MasterName != "" {
+		return NewFailoverClient(opts.failover())
+	} else if len(opts.Addrs) > 1 {
+		return NewClusterClient(opts.cluster())
+	}
+	return NewClient(opts.simple())
+}

vendor/github.com/golang/protobuf/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at http://tip.golang.org/AUTHORS.

vendor/github.com/golang/protobuf/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at http://tip.golang.org/CONTRIBUTORS.

vendor/github.com/golang/protobuf/LICENSE

@@ -0,0 +1,28 @@
+Copyright 2010 The Go Authors.  All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+

vendor/github.com/golang/protobuf/proto/clone.go

@@ -0,0 +1,253 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer deep copy and merge.
+// TODO: RawMessage.
+
+package proto
+
+import (
+	"fmt"
+	"log"
+	"reflect"
+	"strings"
+)
+
+// Clone returns a deep copy of a protocol buffer.
+func Clone(src Message) Message {
+	in := reflect.ValueOf(src)
+	if in.IsNil() {
+		return src
+	}
+	out := reflect.New(in.Type().Elem())
+	dst := out.Interface().(Message)
+	Merge(dst, src)
+	return dst
+}
+
+// Merger is the interface representing objects that can merge messages of the same type.
+type Merger interface {
+	// Merge merges src into this message.
+	// Required and optional fields that are set in src will be set to that value in dst.
+	// Elements of repeated fields will be appended.
+	//
+	// Merge may panic if called with a different argument type than the receiver.
+	Merge(src Message)
+}
+
+// generatedMerger is the custom merge method that generated protos will have.
+// We must add this method since a generate Merge method will conflict with
+// many existing protos that have a Merge data field already defined.
+type generatedMerger interface {
+	XXX_Merge(src Message)
+}
+
+// Merge merges src into dst.
+// Required and optional fields that are set in src will be set to that value in dst.
+// Elements of repeated fields will be appended.
+// Merge panics if src and dst are not the same type, or if dst is nil.
+func Merge(dst, src Message) {
+	if m, ok := dst.(Merger); ok {
+		m.Merge(src)
+		return
+	}
+
+	in := reflect.ValueOf(src)
+	out := reflect.ValueOf(dst)
+	if out.IsNil() {
+		panic("proto: nil destination")
+	}
+	if in.Type() != out.Type() {
+		panic(fmt.Sprintf("proto.Merge(%T, %T) type mismatch", dst, src))
+	}
+	if in.IsNil() {
+		return // Merge from nil src is a noop
+	}
+	if m, ok := dst.(generatedMerger); ok {
+		m.XXX_Merge(src)
+		return
+	}
+	mergeStruct(out.Elem(), in.Elem())
+}
+
+func mergeStruct(out, in reflect.Value) {
+	sprop := GetProperties(in.Type())
+	for i := 0; i < in.NumField(); i++ {
+		f := in.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
+	}
+
+	if emIn, err := extendable(in.Addr().Interface()); err == nil {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
+	}
+
+	uf := in.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return
+	}
+	uin := uf.Bytes()
+	if len(uin) > 0 {
+		out.FieldByName("XXX_unrecognized").SetBytes(append([]byte(nil), uin...))
+	}
+}
+
+// mergeAny performs a merge between two values of the same type.
+// viaPtr indicates whether the values were indirected through a pointer (implying proto2).
+// prop is set if this is a struct field (it may be nil).
+func mergeAny(out, in reflect.Value, viaPtr bool, prop *Properties) {
+	if in.Type() == protoMessageType {
+		if !in.IsNil() {
+			if out.IsNil() {
+				out.Set(reflect.ValueOf(Clone(in.Interface().(Message))))
+			} else {
+				Merge(out.Interface().(Message), in.Interface().(Message))
+			}
+		}
+		return
+	}
+	switch in.Kind() {
+	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+		reflect.String, reflect.Uint32, reflect.Uint64:
+		if !viaPtr && isProto3Zero(in) {
+			return
+		}
+		out.Set(in)
+	case reflect.Interface:
+		// Probably a oneof field; copy non-nil values.
+		if in.IsNil() {
+			return
+		}
+		// Allocate destination if it is not set, or set to a different type.
+		// Otherwise we will merge as normal.
+		if out.IsNil() || out.Elem().Type() != in.Elem().Type() {
+			out.Set(reflect.New(in.Elem().Elem().Type())) // interface -> *T -> T -> new(T)
+		}
+		mergeAny(out.Elem(), in.Elem(), false, nil)
+	case reflect.Map:
+		if in.Len() == 0 {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.MakeMap(in.Type()))
+		}
+		// For maps with value types of *T or []byte we need to deep copy each value.
+		elemKind := in.Type().Elem().Kind()
+		for _, key := range in.MapKeys() {
+			var val reflect.Value
+			switch elemKind {
+			case reflect.Ptr:
+				val = reflect.New(in.Type().Elem().Elem())
+				mergeAny(val, in.MapIndex(key), false, nil)
+			case reflect.Slice:
+				val = in.MapIndex(key)
+				val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+			default:
+				val = in.MapIndex(key)
+			}
+			out.SetMapIndex(key, val)
+		}
+	case reflect.Ptr:
+		if in.IsNil() {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.New(in.Elem().Type()))
+		}
+		mergeAny(out.Elem(), in.Elem(), true, nil)
+	case reflect.Slice:
+		if in.IsNil() {
+			return
+		}
+		if in.Type().Elem().Kind() == reflect.Uint8 {
+			// []byte is a scalar bytes field, not a repeated field.
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value, and should not
+			// be merged.
+			if prop != nil && prop.proto3 && in.Len() == 0 {
+				return
+			}
+
+			// Make a deep copy.
+			// Append to []byte{} instead of []byte(nil) so that we never end up
+			// with a nil result.
+			out.SetBytes(append([]byte{}, in.Bytes()...))
+			return
+		}
+		n := in.Len()
+		if out.IsNil() {
+			out.Set(reflect.MakeSlice(in.Type(), 0, n))
+		}
+		switch in.Type().Elem().Kind() {
+		case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+			reflect.String, reflect.Uint32, reflect.Uint64:
+			out.Set(reflect.AppendSlice(out, in))
+		default:
+			for i := 0; i < n; i++ {
+				x := reflect.Indirect(reflect.New(in.Type().Elem()))
+				mergeAny(x, in.Index(i), false, nil)
+				out.Set(reflect.Append(out, x))
+			}
+		}
+	case reflect.Struct:
+		mergeStruct(out, in)
+	default:
+		// unknown type, so not a protocol buffer
+		log.Printf("proto: don't know how to copy %v", in)
+	}
+}
+
+func mergeExtension(out, in map[int32]Extension) {
+	for extNum, eIn := range in {
+		eOut := Extension{desc: eIn.desc}
+		if eIn.value != nil {
+			v := reflect.New(reflect.TypeOf(eIn.value)).Elem()
+			mergeAny(v, reflect.ValueOf(eIn.value), false, nil)
+			eOut.value = v.Interface()
+		}
+		if eIn.enc != nil {
+			eOut.enc = make([]byte, len(eIn.enc))
+			copy(eOut.enc, eIn.enc)
+		}
+
+		out[extNum] = eOut
+	}
+}

vendor/github.com/golang/protobuf/proto/decode.go

@@ -0,0 +1,428 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for decoding protocol buffer data to construct in-memory representations.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+// errOverflow is returned when an integer is too large to be represented.
+var errOverflow = errors.New("proto: integer overflow")
+
+// ErrInternalBadWireType is returned by generated code when an incorrect
+// wire type is encountered. It does not get returned to user code.
+var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
+
+// DecodeVarint reads a varint-encoded integer from the slice.
+// It returns the integer and the number of bytes consumed, or
+// zero if there is not enough.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func DecodeVarint(buf []byte) (x uint64, n int) {
+	for shift := uint(0); shift < 64; shift += 7 {
+		if n >= len(buf) {
+			return 0, 0
+		}
+		b := uint64(buf[n])
+		n++
+		x |= (b & 0x7F) << shift
+		if (b & 0x80) == 0 {
+			return x, n
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	return 0, 0
+}
+
+func (p *Buffer) decodeVarintSlow() (x uint64, err error) {
+	i := p.index
+	l := len(p.buf)
+
+	for shift := uint(0); shift < 64; shift += 7 {
+		if i >= l {
+			err = io.ErrUnexpectedEOF
+			return
+		}
+		b := p.buf[i]
+		i++
+		x |= (uint64(b) & 0x7F) << shift
+		if b < 0x80 {
+			p.index = i
+			return
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	err = errOverflow
+	return
+}
+
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	i := p.index
+	buf := p.buf
+
+	if i >= len(buf) {
+		return 0, io.ErrUnexpectedEOF
+	} else if buf[i] < 0x80 {
+		p.index++
+		return uint64(buf[i]), nil
+	} else if len(buf)-i < 10 {
+		return p.decodeVarintSlow()
+	}
+
+	var b uint64
+	// we already checked the first byte
+	x = uint64(buf[i]) - 0x80
+	i++
+
+	b = uint64(buf[i])
+	i++
+	x += b << 7
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 7
+
+	b = uint64(buf[i])
+	i++
+	x += b << 14
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 14
+
+	b = uint64(buf[i])
+	i++
+	x += b << 21
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 21
+
+	b = uint64(buf[i])
+	i++
+	x += b << 28
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 28
+
+	b = uint64(buf[i])
+	i++
+	x += b << 35
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 35
+
+	b = uint64(buf[i])
+	i++
+	x += b << 42
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 42
+
+	b = uint64(buf[i])
+	i++
+	x += b << 49
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 49
+
+	b = uint64(buf[i])
+	i++
+	x += b << 56
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 56
+
+	b = uint64(buf[i])
+	i++
+	x += b << 63
+	if b&0x80 == 0 {
+		goto done
+	}
+	// x -= 0x80 << 63 // Always zero.
+
+	return 0, errOverflow
+
+done:
+	p.index = i
+	return x, nil
+}
+
+// DecodeFixed64 reads a 64-bit integer from the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) DecodeFixed64() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 8
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-8])
+	x |= uint64(p.buf[i-7]) << 8
+	x |= uint64(p.buf[i-6]) << 16
+	x |= uint64(p.buf[i-5]) << 24
+	x |= uint64(p.buf[i-4]) << 32
+	x |= uint64(p.buf[i-3]) << 40
+	x |= uint64(p.buf[i-2]) << 48
+	x |= uint64(p.buf[i-1]) << 56
+	return
+}
+
+// DecodeFixed32 reads a 32-bit integer from the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) DecodeFixed32() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 4
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-4])
+	x |= uint64(p.buf[i-3]) << 8
+	x |= uint64(p.buf[i-2]) << 16
+	x |= uint64(p.buf[i-1]) << 24
+	return
+}
+
+// DecodeZigzag64 reads a zigzag-encoded 64-bit integer
+// from the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) DecodeZigzag64() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = (x >> 1) ^ uint64((int64(x&1)<<63)>>63)
+	return
+}
+
+// DecodeZigzag32 reads a zigzag-encoded 32-bit integer
+// from  the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) DecodeZigzag32() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = uint64((uint32(x) >> 1) ^ uint32((int32(x&1)<<31)>>31))
+	return
+}
+
+// DecodeRawBytes reads a count-delimited byte buffer from the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) DecodeRawBytes(alloc bool) (buf []byte, err error) {
+	n, err := p.DecodeVarint()
+	if err != nil {
+		return nil, err
+	}
+
+	nb := int(n)
+	if nb < 0 {
+		return nil, fmt.Errorf("proto: bad byte length %d", nb)
+	}
+	end := p.index + nb
+	if end < p.index || end > len(p.buf) {
+		return nil, io.ErrUnexpectedEOF
+	}
+
+	if !alloc {
+		// todo: check if can get more uses of alloc=false
+		buf = p.buf[p.index:end]
+		p.index += nb
+		return
+	}
+
+	buf = make([]byte, nb)
+	copy(buf, p.buf[p.index:])
+	p.index += nb
+	return
+}
+
+// DecodeStringBytes reads an encoded string from the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) DecodeStringBytes() (s string, err error) {
+	buf, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return
+	}
+	return string(buf), nil
+}
+
+// Unmarshaler is the interface representing objects that can
+// unmarshal themselves.  The argument points to data that may be
+// overwritten, so implementations should not keep references to the
+// buffer.
+// Unmarshal implementations should not clear the receiver.
+// Any unmarshaled data should be merged into the receiver.
+// Callers of Unmarshal that do not want to retain existing data
+// should Reset the receiver before calling Unmarshal.
+type Unmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+// newUnmarshaler is the interface representing objects that can
+// unmarshal themselves. The semantics are identical to Unmarshaler.
+//
+// This exists to support protoc-gen-go generated messages.
+// The proto package will stop type-asserting to this interface in the future.
+//
+// DO NOT DEPEND ON THIS.
+type newUnmarshaler interface {
+	XXX_Unmarshal([]byte) error
+}
+
+// Unmarshal parses the protocol buffer representation in buf and places the
+// decoded result in pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// Unmarshal resets pb before starting to unmarshal, so any
+// existing data in pb is always removed. Use UnmarshalMerge
+// to preserve and append to existing data.
+func Unmarshal(buf []byte, pb Message) error {
+	pb.Reset()
+	if u, ok := pb.(newUnmarshaler); ok {
+		return u.XXX_Unmarshal(buf)
+	}
+	if u, ok := pb.(Unmarshaler); ok {
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
+}
+
+// UnmarshalMerge parses the protocol buffer representation in buf and
+// writes the decoded result to pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// UnmarshalMerge merges into existing data in pb.
+// Most code should use Unmarshal instead.
+func UnmarshalMerge(buf []byte, pb Message) error {
+	if u, ok := pb.(newUnmarshaler); ok {
+		return u.XXX_Unmarshal(buf)
+	}
+	if u, ok := pb.(Unmarshaler); ok {
+		// NOTE: The history of proto have unfortunately been inconsistent
+		// whether Unmarshaler should or should not implicitly clear itself.
+		// Some implementations do, most do not.
+		// Thus, calling this here may or may not do what people want.
+		//
+		// See https://github.com/golang/protobuf/issues/424
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
+}
+
+// DecodeMessage reads a count-delimited message from the Buffer.
+func (p *Buffer) DecodeMessage(pb Message) error {
+	enc, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	return NewBuffer(enc).Unmarshal(pb)
+}
+
+// DecodeGroup reads a tag-delimited group from the Buffer.
+// StartGroup tag is already consumed. This function consumes
+// EndGroup tag.
+func (p *Buffer) DecodeGroup(pb Message) error {
+	b := p.buf[p.index:]
+	x, y := findEndGroup(b)
+	if x < 0 {
+		return io.ErrUnexpectedEOF
+	}
+	err := Unmarshal(b[:x], pb)
+	p.index += y
+	return err
+}
+
+// Unmarshal parses the protocol buffer representation in the
+// Buffer and places the decoded result in pb.  If the struct
+// underlying pb does not match the data in the buffer, the results can be
+// unpredictable.
+//
+// Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
+func (p *Buffer) Unmarshal(pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(newUnmarshaler); ok {
+		err := u.XXX_Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
+		return err
+	}
+	if u, ok := pb.(Unmarshaler); ok {
+		// NOTE: The history of proto have unfortunately been inconsistent
+		// whether Unmarshaler should or should not implicitly clear itself.
+		// Some implementations do, most do not.
+		// Thus, calling this here may or may not do what people want.
+		//
+		// See https://github.com/golang/protobuf/issues/424
+		err := u.Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
+		return err
+	}
+
+	// Slow workaround for messages that aren't Unmarshalers.
+	// This includes some hand-coded .pb.go files and
+	// bootstrap protos.
+	// TODO: fix all of those and then add Unmarshal to
+	// the Message interface. Then:
+	// The cast above and code below can be deleted.
+	// The old unmarshaler can be deleted.
+	// Clients can call Unmarshal directly (can already do that, actually).
+	var info InternalMessageInfo
+	err := info.Unmarshal(pb, p.buf[p.index:])
+	p.index = len(p.buf)
+	return err
+}

vendor/github.com/golang/protobuf/proto/discard.go

@@ -0,0 +1,350 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2017 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+type generatedDiscarder interface {
+	XXX_DiscardUnknown()
+}
+
+// DiscardUnknown recursively discards all unknown fields from this message
+// and all embedded messages.
+//
+// When unmarshaling a message with unrecognized fields, the tags and values
+// of such fields are preserved in the Message. This allows a later call to
+// marshal to be able to produce a message that continues to have those
+// unrecognized fields. To avoid this, DiscardUnknown is used to
+// explicitly clear the unknown fields after unmarshaling.
+//
+// For proto2 messages, the unknown fields of message extensions are only
+// discarded from messages that have been accessed via GetExtension.
+func DiscardUnknown(m Message) {
+	if m, ok := m.(generatedDiscarder); ok {
+		m.XXX_DiscardUnknown()
+		return
+	}
+	// TODO: Dynamically populate a InternalMessageInfo for legacy messages,
+	// but the master branch has no implementation for InternalMessageInfo,
+	// so it would be more work to replicate that approach.
+	discardLegacy(m)
+}
+
+// DiscardUnknown recursively discards all unknown fields.
+func (a *InternalMessageInfo) DiscardUnknown(m Message) {
+	di := atomicLoadDiscardInfo(&a.discard)
+	if di == nil {
+		di = getDiscardInfo(reflect.TypeOf(m).Elem())
+		atomicStoreDiscardInfo(&a.discard, di)
+	}
+	di.discard(toPointer(&m))
+}
+
+type discardInfo struct {
+	typ reflect.Type
+
+	initialized int32 // 0: only typ is valid, 1: everything is valid
+	lock        sync.Mutex
+
+	fields       []discardFieldInfo
+	unrecognized field
+}
+
+type discardFieldInfo struct {
+	field   field // Offset of field, guaranteed to be valid
+	discard func(src pointer)
+}
+
+var (
+	discardInfoMap  = map[reflect.Type]*discardInfo{}
+	discardInfoLock sync.Mutex
+)
+
+func getDiscardInfo(t reflect.Type) *discardInfo {
+	discardInfoLock.Lock()
+	defer discardInfoLock.Unlock()
+	di := discardInfoMap[t]
+	if di == nil {
+		di = &discardInfo{typ: t}
+		discardInfoMap[t] = di
+	}
+	return di
+}
+
+func (di *discardInfo) discard(src pointer) {
+	if src.isNil() {
+		return // Nothing to do.
+	}
+
+	if atomic.LoadInt32(&di.initialized) == 0 {
+		di.computeDiscardInfo()
+	}
+
+	for _, fi := range di.fields {
+		sfp := src.offset(fi.field)
+		fi.discard(sfp)
+	}
+
+	// For proto2 messages, only discard unknown fields in message extensions
+	// that have been accessed via GetExtension.
+	if em, err := extendable(src.asPointerTo(di.typ).Interface()); err == nil {
+		// Ignore lock since DiscardUnknown is not concurrency safe.
+		emm, _ := em.extensionsRead()
+		for _, mx := range emm {
+			if m, ok := mx.value.(Message); ok {
+				DiscardUnknown(m)
+			}
+		}
+	}
+
+	if di.unrecognized.IsValid() {
+		*src.offset(di.unrecognized).toBytes() = nil
+	}
+}
+
+func (di *discardInfo) computeDiscardInfo() {
+	di.lock.Lock()
+	defer di.lock.Unlock()
+	if di.initialized != 0 {
+		return
+	}
+	t := di.typ
+	n := t.NumField()
+
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+
+		dfi := discardFieldInfo{field: toField(&f)}
+		tf := f.Type
+
+		// Unwrap tf to get its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("%v.%s cannot be a slice of pointers to primitive types", t, f.Name))
+		}
+
+		switch tf.Kind() {
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("%v.%s cannot be a direct struct value", t, f.Name))
+			case isSlice: // E.g., []*pb.T
+				di := getDiscardInfo(tf)
+				dfi.discard = func(src pointer) {
+					sps := src.getPointerSlice()
+					for _, sp := range sps {
+						if !sp.isNil() {
+							di.discard(sp)
+						}
+					}
+				}
+			default: // E.g., *pb.T
+				di := getDiscardInfo(tf)
+				dfi.discard = func(src pointer) {
+					sp := src.getPointer()
+					if !sp.isNil() {
+						di.discard(sp)
+					}
+				}
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%v.%s cannot be a pointer to a map or a slice of map values", t, f.Name))
+			default: // E.g., map[K]V
+				if tf.Elem().Kind() == reflect.Ptr { // Proto struct (e.g., *T)
+					dfi.discard = func(src pointer) {
+						sm := src.asPointerTo(tf).Elem()
+						if sm.Len() == 0 {
+							return
+						}
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							DiscardUnknown(val.Interface().(Message))
+						}
+					}
+				} else {
+					dfi.discard = func(pointer) {} // Noop
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%v.%s cannot be a pointer to a interface or a slice of interface values", t, f.Name))
+			default: // E.g., interface{}
+				// TODO: Make this faster?
+				dfi.discard = func(src pointer) {
+					su := src.asPointerTo(tf).Elem()
+					if !su.IsNil() {
+						sv := su.Elem().Elem().Field(0)
+						if sv.Kind() == reflect.Ptr && sv.IsNil() {
+							return
+						}
+						switch sv.Type().Kind() {
+						case reflect.Ptr: // Proto struct (e.g., *T)
+							DiscardUnknown(sv.Interface().(Message))
+						}
+					}
+				}
+			}
+		default:
+			continue
+		}
+		di.fields = append(di.fields, dfi)
+	}
+
+	di.unrecognized = invalidField
+	if f, ok := t.FieldByName("XXX_unrecognized"); ok {
+		if f.Type != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		di.unrecognized = toField(&f)
+	}
+
+	atomic.StoreInt32(&di.initialized, 1)
+}
+
+func discardLegacy(m Message) {
+	v := reflect.ValueOf(m)
+	if v.Kind() != reflect.Ptr || v.IsNil() {
+		return
+	}
+	v = v.Elem()
+	if v.Kind() != reflect.Struct {
+		return
+	}
+	t := v.Type()
+
+	for i := 0; i < v.NumField(); i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		vf := v.Field(i)
+		tf := f.Type
+
+		// Unwrap tf to get its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("%T.%s cannot be a slice of pointers to primitive types", m, f.Name))
+		}
+
+		switch tf.Kind() {
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("%T.%s cannot be a direct struct value", m, f.Name))
+			case isSlice: // E.g., []*pb.T
+				for j := 0; j < vf.Len(); j++ {
+					discardLegacy(vf.Index(j).Interface().(Message))
+				}
+			default: // E.g., *pb.T
+				discardLegacy(vf.Interface().(Message))
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a map or a slice of map values", m, f.Name))
+			default: // E.g., map[K]V
+				tv := vf.Type().Elem()
+				if tv.Kind() == reflect.Ptr && tv.Implements(protoMessageType) { // Proto struct (e.g., *T)
+					for _, key := range vf.MapKeys() {
+						val := vf.MapIndex(key)
+						discardLegacy(val.Interface().(Message))
+					}
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a interface or a slice of interface values", m, f.Name))
+			default: // E.g., test_proto.isCommunique_Union interface
+				if !vf.IsNil() && f.Tag.Get("protobuf_oneof") != "" {
+					vf = vf.Elem() // E.g., *test_proto.Communique_Msg
+					if !vf.IsNil() {
+						vf = vf.Elem()   // E.g., test_proto.Communique_Msg
+						vf = vf.Field(0) // E.g., Proto struct (e.g., *T) or primitive value
+						if vf.Kind() == reflect.Ptr {
+							discardLegacy(vf.Interface().(Message))
+						}
+					}
+				}
+			}
+		}
+	}
+
+	if vf := v.FieldByName("XXX_unrecognized"); vf.IsValid() {
+		if vf.Type() != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		vf.Set(reflect.ValueOf([]byte(nil)))
+	}
+
+	// For proto2 messages, only discard unknown fields in message extensions
+	// that have been accessed via GetExtension.
+	if em, err := extendable(m); err == nil {
+		// Ignore lock since discardLegacy is not concurrency safe.
+		emm, _ := em.extensionsRead()
+		for _, mx := range emm {
+			if m, ok := mx.value.(Message); ok {
+				discardLegacy(m)
+			}
+		}
+	}
+}

vendor/github.com/golang/protobuf/proto/encode.go

@@ -0,0 +1,203 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"errors"
+	"reflect"
+)
+
+var (
+	// errRepeatedHasNil is the error returned if Marshal is called with
+	// a struct with a repeated field containing a nil element.
+	errRepeatedHasNil = errors.New("proto: repeated field has nil element")
+
+	// errOneofHasNil is the error returned if Marshal is called with
+	// a struct with a oneof field containing a nil element.
+	errOneofHasNil = errors.New("proto: oneof field has nil value")
+
+	// ErrNil is the error returned if Marshal is called with nil.
+	ErrNil = errors.New("proto: Marshal called with nil")
+
+	// ErrTooLarge is the error returned if Marshal is called with a
+	// message that encodes to >2GB.
+	ErrTooLarge = errors.New("proto: message encodes to over 2 GB")
+)
+
+// The fundamental encoders that put bytes on the wire.
+// Those that take integer types all accept uint64 and are
+// therefore of type valueEncoder.
+
+const maxVarintBytes = 10 // maximum length of a varint
+
+// EncodeVarint returns the varint encoding of x.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+// Not used by the package itself, but helpful to clients
+// wishing to use the same encoding.
+func EncodeVarint(x uint64) []byte {
+	var buf [maxVarintBytes]byte
+	var n int
+	for n = 0; x > 127; n++ {
+		buf[n] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	buf[n] = uint8(x)
+	n++
+	return buf[0:n]
+}
+
+// EncodeVarint writes a varint-encoded integer to the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) EncodeVarint(x uint64) error {
+	for x >= 1<<7 {
+		p.buf = append(p.buf, uint8(x&0x7f|0x80))
+		x >>= 7
+	}
+	p.buf = append(p.buf, uint8(x))
+	return nil
+}
+
+// SizeVarint returns the varint encoding size of an integer.
+func SizeVarint(x uint64) int {
+	switch {
+	case x < 1<<7:
+		return 1
+	case x < 1<<14:
+		return 2
+	case x < 1<<21:
+		return 3
+	case x < 1<<28:
+		return 4
+	case x < 1<<35:
+		return 5
+	case x < 1<<42:
+		return 6
+	case x < 1<<49:
+		return 7
+	case x < 1<<56:
+		return 8
+	case x < 1<<63:
+		return 9
+	}
+	return 10
+}
+
+// EncodeFixed64 writes a 64-bit integer to the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) EncodeFixed64(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24),
+		uint8(x>>32),
+		uint8(x>>40),
+		uint8(x>>48),
+		uint8(x>>56))
+	return nil
+}
+
+// EncodeFixed32 writes a 32-bit integer to the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) EncodeFixed32(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24))
+	return nil
+}
+
+// EncodeZigzag64 writes a zigzag-encoded 64-bit integer
+// to the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) EncodeZigzag64(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+
+// EncodeZigzag32 writes a zigzag-encoded 32-bit integer
+// to the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) EncodeZigzag32(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
+}
+
+// EncodeRawBytes writes a count-delimited byte buffer to the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) EncodeRawBytes(b []byte) error {
+	p.EncodeVarint(uint64(len(b)))
+	p.buf = append(p.buf, b...)
+	return nil
+}
+
+// EncodeStringBytes writes an encoded string to the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) EncodeStringBytes(s string) error {
+	p.EncodeVarint(uint64(len(s)))
+	p.buf = append(p.buf, s...)
+	return nil
+}
+
+// Marshaler is the interface representing objects that can marshal themselves.
+type Marshaler interface {
+	Marshal() ([]byte, error)
+}
+
+// EncodeMessage writes the protocol buffer to the Buffer,
+// prefixed by a varint-encoded length.
+func (p *Buffer) EncodeMessage(pb Message) error {
+	siz := Size(pb)
+	p.EncodeVarint(uint64(siz))
+	return p.Marshal(pb)
+}
+
+// All protocol buffer fields are nillable, but be careful.
+func isNil(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return v.IsNil()
+	}
+	return false
+}

vendor/github.com/golang/protobuf/proto/equal.go

@@ -0,0 +1,300 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer comparison.
+
+package proto
+
+import (
+	"bytes"
+	"log"
+	"reflect"
+	"strings"
+)
+
+/*
+Equal returns true iff protocol buffers a and b are equal.
+The arguments must both be pointers to protocol buffer structs.
+
+Equality is defined in this way:
+  - Two messages are equal iff they are the same type,
+    corresponding fields are equal, unknown field sets
+    are equal, and extensions sets are equal.
+  - Two set scalar fields are equal iff their values are equal.
+    If the fields are of a floating-point type, remember that
+    NaN != x for all x, including NaN. If the message is defined
+    in a proto3 .proto file, fields are not "set"; specifically,
+    zero length proto3 "bytes" fields are equal (nil == {}).
+  - Two repeated fields are equal iff their lengths are the same,
+    and their corresponding elements are equal. Note a "bytes" field,
+    although represented by []byte, is not a repeated field and the
+    rule for the scalar fields described above applies.
+  - Two unset fields are equal.
+  - Two unknown field sets are equal if their current
+    encoded state is equal.
+  - Two extension sets are equal iff they have corresponding
+    elements that are pairwise equal.
+  - Two map fields are equal iff their lengths are the same,
+    and they contain the same set of elements. Zero-length map
+    fields are equal.
+  - Every other combination of things are not equal.
+
+The return value is undefined if a and b are not protocol buffers.
+*/
+func Equal(a, b Message) bool {
+	if a == nil || b == nil {
+		return a == b
+	}
+	v1, v2 := reflect.ValueOf(a), reflect.ValueOf(b)
+	if v1.Type() != v2.Type() {
+		return false
+	}
+	if v1.Kind() == reflect.Ptr {
+		if v1.IsNil() {
+			return v2.IsNil()
+		}
+		if v2.IsNil() {
+			return false
+		}
+		v1, v2 = v1.Elem(), v2.Elem()
+	}
+	if v1.Kind() != reflect.Struct {
+		return false
+	}
+	return equalStruct(v1, v2)
+}
+
+// v1 and v2 are known to have the same type.
+func equalStruct(v1, v2 reflect.Value) bool {
+	sprop := GetProperties(v1.Type())
+	for i := 0; i < v1.NumField(); i++ {
+		f := v1.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		f1, f2 := v1.Field(i), v2.Field(i)
+		if f.Type.Kind() == reflect.Ptr {
+			if n1, n2 := f1.IsNil(), f2.IsNil(); n1 && n2 {
+				// both unset
+				continue
+			} else if n1 != n2 {
+				// set/unset mismatch
+				return false
+			}
+			f1, f2 = f1.Elem(), f2.Elem()
+		}
+		if !equalAny(f1, f2, sprop.Prop[i]) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_InternalExtensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_InternalExtensions")
+		if !equalExtensions(v1.Type(), em1.Interface().(XXX_InternalExtensions), em2.Interface().(XXX_InternalExtensions)) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_extensions")
+		if !equalExtMap(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
+			return false
+		}
+	}
+
+	uf := v1.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return true
+	}
+
+	u1 := uf.Bytes()
+	u2 := v2.FieldByName("XXX_unrecognized").Bytes()
+	return bytes.Equal(u1, u2)
+}
+
+// v1 and v2 are known to have the same type.
+// prop may be nil.
+func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
+	if v1.Type() == protoMessageType {
+		m1, _ := v1.Interface().(Message)
+		m2, _ := v2.Interface().(Message)
+		return Equal(m1, m2)
+	}
+	switch v1.Kind() {
+	case reflect.Bool:
+		return v1.Bool() == v2.Bool()
+	case reflect.Float32, reflect.Float64:
+		return v1.Float() == v2.Float()
+	case reflect.Int32, reflect.Int64:
+		return v1.Int() == v2.Int()
+	case reflect.Interface:
+		// Probably a oneof field; compare the inner values.
+		n1, n2 := v1.IsNil(), v2.IsNil()
+		if n1 || n2 {
+			return n1 == n2
+		}
+		e1, e2 := v1.Elem(), v2.Elem()
+		if e1.Type() != e2.Type() {
+			return false
+		}
+		return equalAny(e1, e2, nil)
+	case reflect.Map:
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for _, key := range v1.MapKeys() {
+			val2 := v2.MapIndex(key)
+			if !val2.IsValid() {
+				// This key was not found in the second map.
+				return false
+			}
+			if !equalAny(v1.MapIndex(key), val2, nil) {
+				return false
+			}
+		}
+		return true
+	case reflect.Ptr:
+		// Maps may have nil values in them, so check for nil.
+		if v1.IsNil() && v2.IsNil() {
+			return true
+		}
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
+		return equalAny(v1.Elem(), v2.Elem(), prop)
+	case reflect.Slice:
+		if v1.Type().Elem().Kind() == reflect.Uint8 {
+			// short circuit: []byte
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value.
+			if prop != nil && prop.proto3 && v1.Len() == 0 && v2.Len() == 0 {
+				return true
+			}
+			if v1.IsNil() != v2.IsNil() {
+				return false
+			}
+			return bytes.Equal(v1.Interface().([]byte), v2.Interface().([]byte))
+		}
+
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for i := 0; i < v1.Len(); i++ {
+			if !equalAny(v1.Index(i), v2.Index(i), prop) {
+				return false
+			}
+		}
+		return true
+	case reflect.String:
+		return v1.Interface().(string) == v2.Interface().(string)
+	case reflect.Struct:
+		return equalStruct(v1, v2)
+	case reflect.Uint32, reflect.Uint64:
+		return v1.Uint() == v2.Uint()
+	}
+
+	// unknown type, so not a protocol buffer
+	log.Printf("proto: don't know how to compare %v", v1)
+	return false
+}
+
+// base is the struct type that the extensions are based on.
+// x1 and x2 are InternalExtensions.
+func equalExtensions(base reflect.Type, x1, x2 XXX_InternalExtensions) bool {
+	em1, _ := x1.extensionsRead()
+	em2, _ := x2.extensionsRead()
+	return equalExtMap(base, em1, em2)
+}
+
+func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
+	if len(em1) != len(em2) {
+		return false
+	}
+
+	for extNum, e1 := range em1 {
+		e2, ok := em2[extNum]
+		if !ok {
+			return false
+		}
+
+		m1, m2 := e1.value, e2.value
+
+		if m1 == nil && m2 == nil {
+			// Both have only encoded form.
+			if bytes.Equal(e1.enc, e2.enc) {
+				continue
+			}
+			// The bytes are different, but the extensions might still be
+			// equal. We need to decode them to compare.
+		}
+
+		if m1 != nil && m2 != nil {
+			// Both are unencoded.
+			if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+				return false
+			}
+			continue
+		}
+
+		// At least one is encoded. To do a semantically correct comparison
+		// we need to unmarshal them first.
+		var desc *ExtensionDesc
+		if m := extensionMaps[base]; m != nil {
+			desc = m[extNum]
+		}
+		if desc == nil {
+			// If both have only encoded form and the bytes are the same,
+			// it is handled above. We get here when the bytes are different.
+			// We don't know how to decode it, so just compare them as byte
+			// slices.
+			log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
+			return false
+		}
+		var err error
+		if m1 == nil {
+			m1, err = decodeExtension(e1.enc, desc)
+		}
+		if m2 == nil && err == nil {
+			m2, err = decodeExtension(e2.enc, desc)
+		}
+		if err != nil {
+			// The encoded form is invalid.
+			log.Printf("proto: badly encoded extension %d of %v: %v", extNum, base, err)
+			return false
+		}
+		if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+			return false
+		}
+	}
+
+	return true
+}

vendor/github.com/golang/protobuf/proto/extensions.go

@@ -0,0 +1,543 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Types and routines for supporting protocol buffer extensions.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"strconv"
+	"sync"
+)
+
+// ErrMissingExtension is the error returned by GetExtension if the named extension is not in the message.
+var ErrMissingExtension = errors.New("proto: missing extension")
+
+// ExtensionRange represents a range of message extensions for a protocol buffer.
+// Used in code generated by the protocol compiler.
+type ExtensionRange struct {
+	Start, End int32 // both inclusive
+}
+
+// extendableProto is an interface implemented by any protocol buffer generated by the current
+// proto compiler that may be extended.
+type extendableProto interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	extensionsWrite() map[int32]Extension
+	extensionsRead() (map[int32]Extension, sync.Locker)
+}
+
+// extendableProtoV1 is an interface implemented by a protocol buffer generated by the previous
+// version of the proto compiler that may be extended.
+type extendableProtoV1 interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	ExtensionMap() map[int32]Extension
+}
+
+// extensionAdapter is a wrapper around extendableProtoV1 that implements extendableProto.
+type extensionAdapter struct {
+	extendableProtoV1
+}
+
+func (e extensionAdapter) extensionsWrite() map[int32]Extension {
+	return e.ExtensionMap()
+}
+
+func (e extensionAdapter) extensionsRead() (map[int32]Extension, sync.Locker) {
+	return e.ExtensionMap(), notLocker{}
+}
+
+// notLocker is a sync.Locker whose Lock and Unlock methods are nops.
+type notLocker struct{}
+
+func (n notLocker) Lock()   {}
+func (n notLocker) Unlock() {}
+
+// extendable returns the extendableProto interface for the given generated proto message.
+// If the proto message has the old extension format, it returns a wrapper that implements
+// the extendableProto interface.
+func extendable(p interface{}) (extendableProto, error) {
+	switch p := p.(type) {
+	case extendableProto:
+		if isNilPtr(p) {
+			return nil, fmt.Errorf("proto: nil %T is not extendable", p)
+		}
+		return p, nil
+	case extendableProtoV1:
+		if isNilPtr(p) {
+			return nil, fmt.Errorf("proto: nil %T is not extendable", p)
+		}
+		return extensionAdapter{p}, nil
+	}
+	// Don't allocate a specific error containing %T:
+	// this is the hot path for Clone and MarshalText.
+	return nil, errNotExtendable
+}
+
+var errNotExtendable = errors.New("proto: not an extendable proto.Message")
+
+func isNilPtr(x interface{}) bool {
+	v := reflect.ValueOf(x)
+	return v.Kind() == reflect.Ptr && v.IsNil()
+}
+
+// XXX_InternalExtensions is an internal representation of proto extensions.
+//
+// Each generated message struct type embeds an anonymous XXX_InternalExtensions field,
+// thus gaining the unexported 'extensions' method, which can be called only from the proto package.
+//
+// The methods of XXX_InternalExtensions are not concurrency safe in general,
+// but calls to logically read-only methods such as has and get may be executed concurrently.
+type XXX_InternalExtensions struct {
+	// The struct must be indirect so that if a user inadvertently copies a
+	// generated message and its embedded XXX_InternalExtensions, they
+	// avoid the mayhem of a copied mutex.
+	//
+	// The mutex serializes all logically read-only operations to p.extensionMap.
+	// It is up to the client to ensure that write operations to p.extensionMap are
+	// mutually exclusive with other accesses.
+	p *struct {
+		mu           sync.Mutex
+		extensionMap map[int32]Extension
+	}
+}
+
+// extensionsWrite returns the extension map, creating it on first use.
+func (e *XXX_InternalExtensions) extensionsWrite() map[int32]Extension {
+	if e.p == nil {
+		e.p = new(struct {
+			mu           sync.Mutex
+			extensionMap map[int32]Extension
+		})
+		e.p.extensionMap = make(map[int32]Extension)
+	}
+	return e.p.extensionMap
+}
+
+// extensionsRead returns the extensions map for read-only use.  It may be nil.
+// The caller must hold the returned mutex's lock when accessing Elements within the map.
+func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Locker) {
+	if e.p == nil {
+		return nil, nil
+	}
+	return e.p.extensionMap, &e.p.mu
+}
+
+// ExtensionDesc represents an extension specification.
+// Used in generated code from the protocol compiler.
+type ExtensionDesc struct {
+	ExtendedType  Message     // nil pointer to the type that is being extended
+	ExtensionType interface{} // nil pointer to the extension type
+	Field         int32       // field number
+	Name          string      // fully-qualified name of extension, for text formatting
+	Tag           string      // protobuf tag style
+	Filename      string      // name of the file in which the extension is defined
+}
+
+func (ed *ExtensionDesc) repeated() bool {
+	t := reflect.TypeOf(ed.ExtensionType)
+	return t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+}
+
+// Extension represents an extension in a message.
+type Extension struct {
+	// When an extension is stored in a message using SetExtension
+	// only desc and value are set. When the message is marshaled
+	// enc will be set to the encoded form of the message.
+	//
+	// When a message is unmarshaled and contains extensions, each
+	// extension will have only enc set. When such an extension is
+	// accessed using GetExtension (or GetExtensions) desc and value
+	// will be set.
+	desc  *ExtensionDesc
+	value interface{}
+	enc   []byte
+}
+
+// SetRawExtension is for testing only.
+func SetRawExtension(base Message, id int32, b []byte) {
+	epb, err := extendable(base)
+	if err != nil {
+		return
+	}
+	extmap := epb.extensionsWrite()
+	extmap[id] = Extension{enc: b}
+}
+
+// isExtensionField returns true iff the given field number is in an extension range.
+func isExtensionField(pb extendableProto, field int32) bool {
+	for _, er := range pb.ExtensionRangeArray() {
+		if er.Start <= field && field <= er.End {
+			return true
+		}
+	}
+	return false
+}
+
+// checkExtensionTypes checks that the given extension is valid for pb.
+func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
+	var pbi interface{} = pb
+	// Check the extended type.
+	if ea, ok := pbi.(extensionAdapter); ok {
+		pbi = ea.extendableProtoV1
+	}
+	if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b {
+		return fmt.Errorf("proto: bad extended type; %v does not extend %v", b, a)
+	}
+	// Check the range.
+	if !isExtensionField(pb, extension.Field) {
+		return errors.New("proto: bad extension number; not in declared ranges")
+	}
+	return nil
+}
+
+// extPropKey is sufficient to uniquely identify an extension.
+type extPropKey struct {
+	base  reflect.Type
+	field int32
+}
+
+var extProp = struct {
+	sync.RWMutex
+	m map[extPropKey]*Properties
+}{
+	m: make(map[extPropKey]*Properties),
+}
+
+func extensionProperties(ed *ExtensionDesc) *Properties {
+	key := extPropKey{base: reflect.TypeOf(ed.ExtendedType), field: ed.Field}
+
+	extProp.RLock()
+	if prop, ok := extProp.m[key]; ok {
+		extProp.RUnlock()
+		return prop
+	}
+	extProp.RUnlock()
+
+	extProp.Lock()
+	defer extProp.Unlock()
+	// Check again.
+	if prop, ok := extProp.m[key]; ok {
+		return prop
+	}
+
+	prop := new(Properties)
+	prop.Init(reflect.TypeOf(ed.ExtensionType), "unknown_name", ed.Tag, nil)
+	extProp.m[key] = prop
+	return prop
+}
+
+// HasExtension returns whether the given extension is present in pb.
+func HasExtension(pb Message, extension *ExtensionDesc) bool {
+	// TODO: Check types, field numbers, etc.?
+	epb, err := extendable(pb)
+	if err != nil {
+		return false
+	}
+	extmap, mu := epb.extensionsRead()
+	if extmap == nil {
+		return false
+	}
+	mu.Lock()
+	_, ok := extmap[extension.Field]
+	mu.Unlock()
+	return ok
+}
+
+// ClearExtension removes the given extension from pb.
+func ClearExtension(pb Message, extension *ExtensionDesc) {
+	epb, err := extendable(pb)
+	if err != nil {
+		return
+	}
+	// TODO: Check types, field numbers, etc.?
+	extmap := epb.extensionsWrite()
+	delete(extmap, extension.Field)
+}
+
+// GetExtension retrieves a proto2 extended field from pb.
+//
+// If the descriptor is type complete (i.e., ExtensionDesc.ExtensionType is non-nil),
+// then GetExtension parses the encoded field and returns a Go value of the specified type.
+// If the field is not present, then the default value is returned (if one is specified),
+// otherwise ErrMissingExtension is reported.
+//
+// If the descriptor is not type complete (i.e., ExtensionDesc.ExtensionType is nil),
+// then GetExtension returns the raw encoded bytes of the field extension.
+func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
+	}
+
+	if extension.ExtendedType != nil {
+		// can only check type if this is a complete descriptor
+		if err := checkExtensionTypes(epb, extension); err != nil {
+			return nil, err
+		}
+	}
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return defaultExtensionValue(extension)
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	e, ok := emap[extension.Field]
+	if !ok {
+		// defaultExtensionValue returns the default value or
+		// ErrMissingExtension if there is no default.
+		return defaultExtensionValue(extension)
+	}
+
+	if e.value != nil {
+		// Already decoded. Check the descriptor, though.
+		if e.desc != extension {
+			// This shouldn't happen. If it does, it means that
+			// GetExtension was called twice with two different
+			// descriptors with the same field number.
+			return nil, errors.New("proto: descriptor conflict")
+		}
+		return e.value, nil
+	}
+
+	if extension.ExtensionType == nil {
+		// incomplete descriptor
+		return e.enc, nil
+	}
+
+	v, err := decodeExtension(e.enc, extension)
+	if err != nil {
+		return nil, err
+	}
+
+	// Remember the decoded version and drop the encoded version.
+	// That way it is safe to mutate what we return.
+	e.value = v
+	e.desc = extension
+	e.enc = nil
+	emap[extension.Field] = e
+	return e.value, nil
+}
+
+// defaultExtensionValue returns the default value for extension.
+// If no default for an extension is defined ErrMissingExtension is returned.
+func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
+	if extension.ExtensionType == nil {
+		// incomplete descriptor, so no default
+		return nil, ErrMissingExtension
+	}
+
+	t := reflect.TypeOf(extension.ExtensionType)
+	props := extensionProperties(extension)
+
+	sf, _, err := fieldDefault(t, props)
+	if err != nil {
+		return nil, err
+	}
+
+	if sf == nil || sf.value == nil {
+		// There is no default value.
+		return nil, ErrMissingExtension
+	}
+
+	if t.Kind() != reflect.Ptr {
+		// We do not need to return a Ptr, we can directly return sf.value.
+		return sf.value, nil
+	}
+
+	// We need to return an interface{} that is a pointer to sf.value.
+	value := reflect.New(t).Elem()
+	value.Set(reflect.New(value.Type().Elem()))
+	if sf.kind == reflect.Int32 {
+		// We may have an int32 or an enum, but the underlying data is int32.
+		// Since we can't set an int32 into a non int32 reflect.value directly
+		// set it as a int32.
+		value.Elem().SetInt(int64(sf.value.(int32)))
+	} else {
+		value.Elem().Set(reflect.ValueOf(sf.value))
+	}
+	return value.Interface(), nil
+}
+
+// decodeExtension decodes an extension encoded in b.
+func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
+	t := reflect.TypeOf(extension.ExtensionType)
+	unmarshal := typeUnmarshaler(t, extension.Tag)
+
+	// t is a pointer to a struct, pointer to basic type or a slice.
+	// Allocate space to store the pointer/slice.
+	value := reflect.New(t).Elem()
+
+	var err error
+	for {
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		wire := int(x) & 7
+
+		b, err = unmarshal(b, valToPointer(value.Addr()), wire)
+		if err != nil {
+			return nil, err
+		}
+
+		if len(b) == 0 {
+			break
+		}
+	}
+	return value.Interface(), nil
+}
+
+// GetExtensions returns a slice of the extensions present in pb that are also listed in es.
+// The returned slice has the same length as es; missing extensions will appear as nil elements.
+func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
+	}
+	extensions = make([]interface{}, len(es))
+	for i, e := range es {
+		extensions[i], err = GetExtension(epb, e)
+		if err == ErrMissingExtension {
+			err = nil
+		}
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// ExtensionDescs returns a new slice containing pb's extension descriptors, in undefined order.
+// For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing
+// just the Field field, which defines the extension's field number.
+func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
+	}
+	registeredExtensions := RegisteredExtensions(pb)
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return nil, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	extensions := make([]*ExtensionDesc, 0, len(emap))
+	for extid, e := range emap {
+		desc := e.desc
+		if desc == nil {
+			desc = registeredExtensions[extid]
+			if desc == nil {
+				desc = &ExtensionDesc{Field: extid}
+			}
+		}
+
+		extensions = append(extensions, desc)
+	}
+	return extensions, nil
+}
+
+// SetExtension sets the specified extension of pb to the specified value.
+func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error {
+	epb, err := extendable(pb)
+	if err != nil {
+		return err
+	}
+	if err := checkExtensionTypes(epb, extension); err != nil {
+		return err
+	}
+	typ := reflect.TypeOf(extension.ExtensionType)
+	if typ != reflect.TypeOf(value) {
+		return errors.New("proto: bad extension value type")
+	}
+	// nil extension values need to be caught early, because the
+	// encoder can't distinguish an ErrNil due to a nil extension
+	// from an ErrNil due to a missing field. Extensions are
+	// always optional, so the encoder would just swallow the error
+	// and drop all the extensions from the encoded message.
+	if reflect.ValueOf(value).IsNil() {
+		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
+	}
+
+	extmap := epb.extensionsWrite()
+	extmap[extension.Field] = Extension{desc: extension, value: value}
+	return nil
+}
+
+// ClearAllExtensions clears all extensions from pb.
+func ClearAllExtensions(pb Message) {
+	epb, err := extendable(pb)
+	if err != nil {
+		return
+	}
+	m := epb.extensionsWrite()
+	for k := range m {
+		delete(m, k)
+	}
+}
+
+// A global registry of extensions.
+// The generated code will register the generated descriptors by calling RegisterExtension.
+
+var extensionMaps = make(map[reflect.Type]map[int32]*ExtensionDesc)
+
+// RegisterExtension is called from the generated code.
+func RegisterExtension(desc *ExtensionDesc) {
+	st := reflect.TypeOf(desc.ExtendedType).Elem()
+	m := extensionMaps[st]
+	if m == nil {
+		m = make(map[int32]*ExtensionDesc)
+		extensionMaps[st] = m
+	}
+	if _, ok := m[desc.Field]; ok {
+		panic("proto: duplicate extension registered: " + st.String() + " " + strconv.Itoa(int(desc.Field)))
+	}
+	m[desc.Field] = desc
+}
+
+// RegisteredExtensions returns a map of the registered extensions of a
+// protocol buffer struct, indexed by the extension number.
+// The argument pb should be a nil pointer to the struct type.
+func RegisteredExtensions(pb Message) map[int32]*ExtensionDesc {
+	return extensionMaps[reflect.TypeOf(pb).Elem()]
+}

vendor/github.com/golang/protobuf/proto/lib.go

@@ -0,0 +1,979 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/*
+Package proto converts data structures to and from the wire format of
+protocol buffers.  It works in concert with the Go source code generated
+for .proto files by the protocol compiler.
+
+A summary of the properties of the protocol buffer interface
+for a protocol buffer variable v:
+
+  - Names are turned from camel_case to CamelCase for export.
+  - There are no methods on v to set fields; just treat
+	them as structure fields.
+  - There are getters that return a field's value if set,
+	and return the field's default value if unset.
+	The getters work even if the receiver is a nil message.
+  - The zero value for a struct is its correct initialization state.
+	All desired fields must be set before marshaling.
+  - A Reset() method will restore a protobuf struct to its zero state.
+  - Non-repeated fields are pointers to the values; nil means unset.
+	That is, optional or required field int32 f becomes F *int32.
+  - Repeated fields are slices.
+  - Helper functions are available to aid the setting of fields.
+	msg.Foo = proto.String("hello") // set field
+  - Constants are defined to hold the default values of all fields that
+	have them.  They have the form Default_StructName_FieldName.
+	Because the getter methods handle defaulted values,
+	direct use of these constants should be rare.
+  - Enums are given type names and maps from names to values.
+	Enum values are prefixed by the enclosing message's name, or by the
+	enum's type name if it is a top-level enum. Enum types have a String
+	method, and a Enum method to assist in message construction.
+  - Nested messages, groups and enums have type names prefixed with the name of
+	the surrounding message type.
+  - Extensions are given descriptor names that start with E_,
+	followed by an underscore-delimited list of the nested messages
+	that contain it (if any) followed by the CamelCased name of the
+	extension field itself.  HasExtension, ClearExtension, GetExtension
+	and SetExtension are functions for manipulating extensions.
+  - Oneof field sets are given a single field in their message,
+	with distinguished wrapper types for each possible field value.
+  - Marshal and Unmarshal are functions to encode and decode the wire format.
+
+When the .proto file specifies `syntax="proto3"`, there are some differences:
+
+  - Non-repeated fields of non-message type are values instead of pointers.
+  - Enum types do not get an Enum method.
+
+The simplest way to describe this is to see an example.
+Given file test.proto, containing
+
+	package example;
+
+	enum FOO { X = 17; }
+
+	message Test {
+	  required string label = 1;
+	  optional int32 type = 2 [default=77];
+	  repeated int64 reps = 3;
+	  optional group OptionalGroup = 4 {
+	    required string RequiredField = 5;
+	  }
+	  oneof union {
+	    int32 number = 6;
+	    string name = 7;
+	  }
+	}
+
+The resulting file, test.pb.go, is:
+
+	package example
+
+	import proto "github.com/golang/protobuf/proto"
+	import math "math"
+
+	type FOO int32
+	const (
+		FOO_X FOO = 17
+	)
+	var FOO_name = map[int32]string{
+		17: "X",
+	}
+	var FOO_value = map[string]int32{
+		"X": 17,
+	}
+
+	func (x FOO) Enum() *FOO {
+		p := new(FOO)
+		*p = x
+		return p
+	}
+	func (x FOO) String() string {
+		return proto.EnumName(FOO_name, int32(x))
+	}
+	func (x *FOO) UnmarshalJSON(data []byte) error {
+		value, err := proto.UnmarshalJSONEnum(FOO_value, data)
+		if err != nil {
+			return err
+		}
+		*x = FOO(value)
+		return nil
+	}
+
+	type Test struct {
+		Label         *string             `protobuf:"bytes,1,req,name=label" json:"label,omitempty"`
+		Type          *int32              `protobuf:"varint,2,opt,name=type,def=77" json:"type,omitempty"`
+		Reps          []int64             `protobuf:"varint,3,rep,name=reps" json:"reps,omitempty"`
+		Optionalgroup *Test_OptionalGroup `protobuf:"group,4,opt,name=OptionalGroup" json:"optionalgroup,omitempty"`
+		// Types that are valid to be assigned to Union:
+		//	*Test_Number
+		//	*Test_Name
+		Union            isTest_Union `protobuf_oneof:"union"`
+		XXX_unrecognized []byte       `json:"-"`
+	}
+	func (m *Test) Reset()         { *m = Test{} }
+	func (m *Test) String() string { return proto.CompactTextString(m) }
+	func (*Test) ProtoMessage() {}
+
+	type isTest_Union interface {
+		isTest_Union()
+	}
+
+	type Test_Number struct {
+		Number int32 `protobuf:"varint,6,opt,name=number"`
+	}
+	type Test_Name struct {
+		Name string `protobuf:"bytes,7,opt,name=name"`
+	}
+
+	func (*Test_Number) isTest_Union() {}
+	func (*Test_Name) isTest_Union()   {}
+
+	func (m *Test) GetUnion() isTest_Union {
+		if m != nil {
+			return m.Union
+		}
+		return nil
+	}
+	const Default_Test_Type int32 = 77
+
+	func (m *Test) GetLabel() string {
+		if m != nil && m.Label != nil {
+			return *m.Label
+		}
+		return ""
+	}
+
+	func (m *Test) GetType() int32 {
+		if m != nil && m.Type != nil {
+			return *m.Type
+		}
+		return Default_Test_Type
+	}
+
+	func (m *Test) GetOptionalgroup() *Test_OptionalGroup {
+		if m != nil {
+			return m.Optionalgroup
+		}
+		return nil
+	}
+
+	type Test_OptionalGroup struct {
+		RequiredField *string `protobuf:"bytes,5,req" json:"RequiredField,omitempty"`
+	}
+	func (m *Test_OptionalGroup) Reset()         { *m = Test_OptionalGroup{} }
+	func (m *Test_OptionalGroup) String() string { return proto.CompactTextString(m) }
+
+	func (m *Test_OptionalGroup) GetRequiredField() string {
+		if m != nil && m.RequiredField != nil {
+			return *m.RequiredField
+		}
+		return ""
+	}
+
+	func (m *Test) GetNumber() int32 {
+		if x, ok := m.GetUnion().(*Test_Number); ok {
+			return x.Number
+		}
+		return 0
+	}
+
+	func (m *Test) GetName() string {
+		if x, ok := m.GetUnion().(*Test_Name); ok {
+			return x.Name
+		}
+		return ""
+	}
+
+	func init() {
+		proto.RegisterEnum("example.FOO", FOO_name, FOO_value)
+	}
+
+To create and play with a Test object:
+
+	package main
+
+	import (
+		"log"
+
+		"github.com/golang/protobuf/proto"
+		pb "./example.pb"
+	)
+
+	func main() {
+		test := &pb.Test{
+			Label: proto.String("hello"),
+			Type:  proto.Int32(17),
+			Reps:  []int64{1, 2, 3},
+			Optionalgroup: &pb.Test_OptionalGroup{
+				RequiredField: proto.String("good bye"),
+			},
+			Union: &pb.Test_Name{"fred"},
+		}
+		data, err := proto.Marshal(test)
+		if err != nil {
+			log.Fatal("marshaling error: ", err)
+		}
+		newTest := &pb.Test{}
+		err = proto.Unmarshal(data, newTest)
+		if err != nil {
+			log.Fatal("unmarshaling error: ", err)
+		}
+		// Now test and newTest contain the same data.
+		if test.GetLabel() != newTest.GetLabel() {
+			log.Fatalf("data mismatch %q != %q", test.GetLabel(), newTest.GetLabel())
+		}
+		// Use a type switch to determine which oneof was set.
+		switch u := test.Union.(type) {
+		case *pb.Test_Number: // u.Number contains the number.
+		case *pb.Test_Name: // u.Name contains the string.
+		}
+		// etc.
+	}
+*/
+package proto
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"reflect"
+	"sort"
+	"strconv"
+	"sync"
+)
+
+// RequiredNotSetError is an error type returned by either Marshal or Unmarshal.
+// Marshal reports this when a required field is not initialized.
+// Unmarshal reports this when a required field is missing from the wire data.
+type RequiredNotSetError struct{ field string }
+
+func (e *RequiredNotSetError) Error() string {
+	if e.field == "" {
+		return fmt.Sprintf("proto: required field not set")
+	}
+	return fmt.Sprintf("proto: required field %q not set", e.field)
+}
+func (e *RequiredNotSetError) RequiredNotSet() bool {
+	return true
+}
+
+type invalidUTF8Error struct{ field string }
+
+func (e *invalidUTF8Error) Error() string {
+	if e.field == "" {
+		return "proto: invalid UTF-8 detected"
+	}
+	return fmt.Sprintf("proto: field %q contains invalid UTF-8", e.field)
+}
+func (e *invalidUTF8Error) InvalidUTF8() bool {
+	return true
+}
+
+// errInvalidUTF8 is a sentinel error to identify fields with invalid UTF-8.
+// This error should not be exposed to the external API as such errors should
+// be recreated with the field information.
+var errInvalidUTF8 = &invalidUTF8Error{}
+
+// isNonFatal reports whether the error is either a RequiredNotSet error
+// or a InvalidUTF8 error.
+func isNonFatal(err error) bool {
+	if re, ok := err.(interface{ RequiredNotSet() bool }); ok && re.RequiredNotSet() {
+		return true
+	}
+	if re, ok := err.(interface{ InvalidUTF8() bool }); ok && re.InvalidUTF8() {
+		return true
+	}
+	return false
+}
+
+type nonFatal struct{ E error }
+
+// Merge merges err into nf and reports whether it was successful.
+// Otherwise it returns false for any fatal non-nil errors.
+func (nf *nonFatal) Merge(err error) (ok bool) {
+	if err == nil {
+		return true // not an error
+	}
+	if !isNonFatal(err) {
+		return false // fatal error
+	}
+	if nf.E == nil {
+		nf.E = err // store first instance of non-fatal error
+	}
+	return true
+}
+
+// Message is implemented by generated protocol buffer messages.
+type Message interface {
+	Reset()
+	String() string
+	ProtoMessage()
+}
+
+// Stats records allocation details about the protocol buffer encoders
+// and decoders.  Useful for tuning the library itself.
+type Stats struct {
+	Emalloc uint64 // mallocs in encode
+	Dmalloc uint64 // mallocs in decode
+	Encode  uint64 // number of encodes
+	Decode  uint64 // number of decodes
+	Chit    uint64 // number of cache hits
+	Cmiss   uint64 // number of cache misses
+	Size    uint64 // number of sizes
+}
+
+// Set to true to enable stats collection.
+const collectStats = false
+
+var stats Stats
+
+// GetStats returns a copy of the global Stats structure.
+func GetStats() Stats { return stats }
+
+// A Buffer is a buffer manager for marshaling and unmarshaling
+// protocol buffers.  It may be reused between invocations to
+// reduce memory usage.  It is not necessary to use a Buffer;
+// the global functions Marshal and Unmarshal create a
+// temporary Buffer and are fine for most applications.
+type Buffer struct {
+	buf   []byte // encode/decode byte stream
+	index int    // read point
+
+	deterministic bool
+}
+
+// NewBuffer allocates a new Buffer and initializes its internal data to
+// the contents of the argument slice.
+func NewBuffer(e []byte) *Buffer {
+	return &Buffer{buf: e}
+}
+
+// Reset resets the Buffer, ready for marshaling a new protocol buffer.
+func (p *Buffer) Reset() {
+	p.buf = p.buf[0:0] // for reading/writing
+	p.index = 0        // for reading
+}
+
+// SetBuf replaces the internal buffer with the slice,
+// ready for unmarshaling the contents of the slice.
+func (p *Buffer) SetBuf(s []byte) {
+	p.buf = s
+	p.index = 0
+}
+
+// Bytes returns the contents of the Buffer.
+func (p *Buffer) Bytes() []byte { return p.buf }
+
+// SetDeterministic sets whether to use deterministic serialization.
+//
+// Deterministic serialization guarantees that for a given binary, equal
+// messages will always be serialized to the same bytes. This implies:
+//
+//   - Repeated serialization of a message will return the same bytes.
+//   - Different processes of the same binary (which may be executing on
+//     different machines) will serialize equal messages to the same bytes.
+//
+// Note that the deterministic serialization is NOT canonical across
+// languages. It is not guaranteed to remain stable over time. It is unstable
+// across different builds with schema changes due to unknown fields.
+// Users who need canonical serialization (e.g., persistent storage in a
+// canonical form, fingerprinting, etc.) should define their own
+// canonicalization specification and implement their own serializer rather
+// than relying on this API.
+//
+// If deterministic serialization is requested, map entries will be sorted
+// by keys in lexographical order. This is an implementation detail and
+// subject to change.
+func (p *Buffer) SetDeterministic(deterministic bool) {
+	p.deterministic = deterministic
+}
+
+/*
+ * Helper routines for simplifying the creation of optional fields of basic type.
+ */
+
+// Bool is a helper routine that allocates a new bool value
+// to store v and returns a pointer to it.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// Int32 is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it.
+func Int32(v int32) *int32 {
+	return &v
+}
+
+// Int is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it, but unlike Int32
+// its argument value is an int.
+func Int(v int) *int32 {
+	p := new(int32)
+	*p = int32(v)
+	return p
+}
+
+// Int64 is a helper routine that allocates a new int64 value
+// to store v and returns a pointer to it.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Float32 is a helper routine that allocates a new float32 value
+// to store v and returns a pointer to it.
+func Float32(v float32) *float32 {
+	return &v
+}
+
+// Float64 is a helper routine that allocates a new float64 value
+// to store v and returns a pointer to it.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Uint32 is a helper routine that allocates a new uint32 value
+// to store v and returns a pointer to it.
+func Uint32(v uint32) *uint32 {
+	return &v
+}
+
+// Uint64 is a helper routine that allocates a new uint64 value
+// to store v and returns a pointer to it.
+func Uint64(v uint64) *uint64 {
+	return &v
+}
+
+// String is a helper routine that allocates a new string value
+// to store v and returns a pointer to it.
+func String(v string) *string {
+	return &v
+}
+
+// EnumName is a helper function to simplify printing protocol buffer enums
+// by name.  Given an enum map and a value, it returns a useful string.
+func EnumName(m map[int32]string, v int32) string {
+	s, ok := m[v]
+	if ok {
+		return s
+	}
+	return strconv.Itoa(int(v))
+}
+
+// UnmarshalJSONEnum is a helper function to simplify recovering enum int values
+// from their JSON-encoded representation. Given a map from the enum's symbolic
+// names to its int values, and a byte buffer containing the JSON-encoded
+// value, it returns an int32 that can be cast to the enum type by the caller.
+//
+// The function can deal with both JSON representations, numeric and symbolic.
+func UnmarshalJSONEnum(m map[string]int32, data []byte, enumName string) (int32, error) {
+	if data[0] == '"' {
+		// New style: enums are strings.
+		var repr string
+		if err := json.Unmarshal(data, &repr); err != nil {
+			return -1, err
+		}
+		val, ok := m[repr]
+		if !ok {
+			return 0, fmt.Errorf("unrecognized enum %s value %q", enumName, repr)
+		}
+		return val, nil
+	}
+	// Old style: enums are ints.
+	var val int32
+	if err := json.Unmarshal(data, &val); err != nil {
+		return 0, fmt.Errorf("cannot unmarshal %#q into enum %s", data, enumName)
+	}
+	return val, nil
+}
+
+// DebugPrint dumps the encoded data in b in a debugging format with a header
+// including the string s. Used in testing but made available for general debugging.
+func (p *Buffer) DebugPrint(s string, b []byte) {
+	var u uint64
+
+	obuf := p.buf
+	index := p.index
+	p.buf = b
+	p.index = 0
+	depth := 0
+
+	fmt.Printf("\n--- %s ---\n", s)
+
+out:
+	for {
+		for i := 0; i < depth; i++ {
+			fmt.Print("  ")
+		}
+
+		index := p.index
+		if index == len(p.buf) {
+			break
+		}
+
+		op, err := p.DecodeVarint()
+		if err != nil {
+			fmt.Printf("%3d: fetching op err %v\n", index, err)
+			break out
+		}
+		tag := op >> 3
+		wire := op & 7
+
+		switch wire {
+		default:
+			fmt.Printf("%3d: t=%3d unknown wire=%d\n",
+				index, tag, wire)
+			break out
+
+		case WireBytes:
+			var r []byte
+
+			r, err = p.DecodeRawBytes(false)
+			if err != nil {
+				break out
+			}
+			fmt.Printf("%3d: t=%3d bytes [%d]", index, tag, len(r))
+			if len(r) <= 6 {
+				for i := 0; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			} else {
+				for i := 0; i < 3; i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+				fmt.Printf(" ..")
+				for i := len(r) - 3; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			}
+			fmt.Printf("\n")
+
+		case WireFixed32:
+			u, err = p.DecodeFixed32()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix32 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix32 %d\n", index, tag, u)
+
+		case WireFixed64:
+			u, err = p.DecodeFixed64()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix64 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix64 %d\n", index, tag, u)
+
+		case WireVarint:
+			u, err = p.DecodeVarint()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d varint err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d varint %d\n", index, tag, u)
+
+		case WireStartGroup:
+			fmt.Printf("%3d: t=%3d start\n", index, tag)
+			depth++
+
+		case WireEndGroup:
+			depth--
+			fmt.Printf("%3d: t=%3d end\n", index, tag)
+		}
+	}
+
+	if depth != 0 {
+		fmt.Printf("%3d: start-end not balanced %d\n", p.index, depth)
+	}
+	fmt.Printf("\n")
+
+	p.buf = obuf
+	p.index = index
+}
+
+// SetDefaults sets unset protocol buffer fields to their default values.
+// It only modifies fields that are both unset and have defined defaults.
+// It recursively sets default values in any non-nil sub-messages.
+func SetDefaults(pb Message) {
+	setDefaults(reflect.ValueOf(pb), true, false)
+}
+
+// v is a pointer to a struct.
+func setDefaults(v reflect.Value, recur, zeros bool) {
+	v = v.Elem()
+
+	defaultMu.RLock()
+	dm, ok := defaults[v.Type()]
+	defaultMu.RUnlock()
+	if !ok {
+		dm = buildDefaultMessage(v.Type())
+		defaultMu.Lock()
+		defaults[v.Type()] = dm
+		defaultMu.Unlock()
+	}
+
+	for _, sf := range dm.scalars {
+		f := v.Field(sf.index)
+		if !f.IsNil() {
+			// field already set
+			continue
+		}
+		dv := sf.value
+		if dv == nil && !zeros {
+			// no explicit default, and don't want to set zeros
+			continue
+		}
+		fptr := f.Addr().Interface() // **T
+		// TODO: Consider batching the allocations we do here.
+		switch sf.kind {
+		case reflect.Bool:
+			b := new(bool)
+			if dv != nil {
+				*b = dv.(bool)
+			}
+			*(fptr.(**bool)) = b
+		case reflect.Float32:
+			f := new(float32)
+			if dv != nil {
+				*f = dv.(float32)
+			}
+			*(fptr.(**float32)) = f
+		case reflect.Float64:
+			f := new(float64)
+			if dv != nil {
+				*f = dv.(float64)
+			}
+			*(fptr.(**float64)) = f
+		case reflect.Int32:
+			// might be an enum
+			if ft := f.Type(); ft != int32PtrType {
+				// enum
+				f.Set(reflect.New(ft.Elem()))
+				if dv != nil {
+					f.Elem().SetInt(int64(dv.(int32)))
+				}
+			} else {
+				// int32 field
+				i := new(int32)
+				if dv != nil {
+					*i = dv.(int32)
+				}
+				*(fptr.(**int32)) = i
+			}
+		case reflect.Int64:
+			i := new(int64)
+			if dv != nil {
+				*i = dv.(int64)
+			}
+			*(fptr.(**int64)) = i
+		case reflect.String:
+			s := new(string)
+			if dv != nil {
+				*s = dv.(string)
+			}
+			*(fptr.(**string)) = s
+		case reflect.Uint8:
+			// exceptional case: []byte
+			var b []byte
+			if dv != nil {
+				db := dv.([]byte)
+				b = make([]byte, len(db))
+				copy(b, db)
+			} else {
+				b = []byte{}
+			}
+			*(fptr.(*[]byte)) = b
+		case reflect.Uint32:
+			u := new(uint32)
+			if dv != nil {
+				*u = dv.(uint32)
+			}
+			*(fptr.(**uint32)) = u
+		case reflect.Uint64:
+			u := new(uint64)
+			if dv != nil {
+				*u = dv.(uint64)
+			}
+			*(fptr.(**uint64)) = u
+		default:
+			log.Printf("proto: can't set default for field %v (sf.kind=%v)", f, sf.kind)
+		}
+	}
+
+	for _, ni := range dm.nested {
+		f := v.Field(ni)
+		// f is *T or []*T or map[T]*T
+		switch f.Kind() {
+		case reflect.Ptr:
+			if f.IsNil() {
+				continue
+			}
+			setDefaults(f, recur, zeros)
+
+		case reflect.Slice:
+			for i := 0; i < f.Len(); i++ {
+				e := f.Index(i)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+
+		case reflect.Map:
+			for _, k := range f.MapKeys() {
+				e := f.MapIndex(k)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+		}
+	}
+}
+
+var (
+	// defaults maps a protocol buffer struct type to a slice of the fields,
+	// with its scalar fields set to their proto-declared non-zero default values.
+	defaultMu sync.RWMutex
+	defaults  = make(map[reflect.Type]defaultMessage)
+
+	int32PtrType = reflect.TypeOf((*int32)(nil))
+)
+
+// defaultMessage represents information about the default values of a message.
+type defaultMessage struct {
+	scalars []scalarField
+	nested  []int // struct field index of nested messages
+}
+
+type scalarField struct {
+	index int          // struct field index
+	kind  reflect.Kind // element type (the T in *T or []T)
+	value interface{}  // the proto-declared default value, or nil
+}
+
+// t is a struct type.
+func buildDefaultMessage(t reflect.Type) (dm defaultMessage) {
+	sprop := GetProperties(t)
+	for _, prop := range sprop.Prop {
+		fi, ok := sprop.decoderTags.get(prop.Tag)
+		if !ok {
+			// XXX_unrecognized
+			continue
+		}
+		ft := t.Field(fi).Type
+
+		sf, nested, err := fieldDefault(ft, prop)
+		switch {
+		case err != nil:
+			log.Print(err)
+		case nested:
+			dm.nested = append(dm.nested, fi)
+		case sf != nil:
+			sf.index = fi
+			dm.scalars = append(dm.scalars, *sf)
+		}
+	}
+
+	return dm
+}
+
+// fieldDefault returns the scalarField for field type ft.
+// sf will be nil if the field can not have a default.
+// nestedMessage will be true if this is a nested message.
+// Note that sf.index is not set on return.
+func fieldDefault(ft reflect.Type, prop *Properties) (sf *scalarField, nestedMessage bool, err error) {
+	var canHaveDefault bool
+	switch ft.Kind() {
+	case reflect.Ptr:
+		if ft.Elem().Kind() == reflect.Struct {
+			nestedMessage = true
+		} else {
+			canHaveDefault = true // proto2 scalar field
+		}
+
+	case reflect.Slice:
+		switch ft.Elem().Kind() {
+		case reflect.Ptr:
+			nestedMessage = true // repeated message
+		case reflect.Uint8:
+			canHaveDefault = true // bytes field
+		}
+
+	case reflect.Map:
+		if ft.Elem().Kind() == reflect.Ptr {
+			nestedMessage = true // map with message values
+		}
+	}
+
+	if !canHaveDefault {
+		if nestedMessage {
+			return nil, true, nil
+		}
+		return nil, false, nil
+	}
+
+	// We now know that ft is a pointer or slice.
+	sf = &scalarField{kind: ft.Elem().Kind()}
+
+	// scalar fields without defaults
+	if !prop.HasDefault {
+		return sf, false, nil
+	}
+
+	// a scalar field: either *T or []byte
+	switch ft.Elem().Kind() {
+	case reflect.Bool:
+		x, err := strconv.ParseBool(prop.Default)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default bool %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Float32:
+		x, err := strconv.ParseFloat(prop.Default, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float32 %q: %v", prop.Default, err)
+		}
+		sf.value = float32(x)
+	case reflect.Float64:
+		x, err := strconv.ParseFloat(prop.Default, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Int32:
+		x, err := strconv.ParseInt(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int32 %q: %v", prop.Default, err)
+		}
+		sf.value = int32(x)
+	case reflect.Int64:
+		x, err := strconv.ParseInt(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.String:
+		sf.value = prop.Default
+	case reflect.Uint8:
+		// []byte (not *uint8)
+		sf.value = []byte(prop.Default)
+	case reflect.Uint32:
+		x, err := strconv.ParseUint(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint32 %q: %v", prop.Default, err)
+		}
+		sf.value = uint32(x)
+	case reflect.Uint64:
+		x, err := strconv.ParseUint(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	default:
+		return nil, false, fmt.Errorf("proto: unhandled def kind %v", ft.Elem().Kind())
+	}
+
+	return sf, false, nil
+}
+
+// mapKeys returns a sort.Interface to be used for sorting the map keys.
+// Map fields may have key types of non-float scalars, strings and enums.
+func mapKeys(vs []reflect.Value) sort.Interface {
+	s := mapKeySorter{vs: vs}
+
+	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps.
+	if len(vs) == 0 {
+		return s
+	}
+	switch vs[0].Kind() {
+	case reflect.Int32, reflect.Int64:
+		s.less = func(a, b reflect.Value) bool { return a.Int() < b.Int() }
+	case reflect.Uint32, reflect.Uint64:
+		s.less = func(a, b reflect.Value) bool { return a.Uint() < b.Uint() }
+	case reflect.Bool:
+		s.less = func(a, b reflect.Value) bool { return !a.Bool() && b.Bool() } // false < true
+	case reflect.String:
+		s.less = func(a, b reflect.Value) bool { return a.String() < b.String() }
+	default:
+		panic(fmt.Sprintf("unsupported map key type: %v", vs[0].Kind()))
+	}
+
+	return s
+}
+
+type mapKeySorter struct {
+	vs   []reflect.Value
+	less func(a, b reflect.Value) bool
+}
+
+func (s mapKeySorter) Len() int      { return len(s.vs) }
+func (s mapKeySorter) Swap(i, j int) { s.vs[i], s.vs[j] = s.vs[j], s.vs[i] }
+func (s mapKeySorter) Less(i, j int) bool {
+	return s.less(s.vs[i], s.vs[j])
+}
+
+// isProto3Zero reports whether v is a zero proto3 value.
+func isProto3Zero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint32, reflect.Uint64:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.String:
+		return v.String() == ""
+	}
+	return false
+}
+
+// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion2 = true
+
+// ProtoPackageIsVersion1 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion1 = true
+
+// InternalMessageInfo is a type used internally by generated .pb.go files.
+// This type is not intended to be used by non-generated code.
+// This type is not subject to any compatibility guarantee.
+type InternalMessageInfo struct {
+	marshal   *marshalInfo
+	unmarshal *unmarshalInfo
+	merge     *mergeInfo
+	discard   *discardInfo
+}

vendor/github.com/golang/protobuf/proto/message_set.go

@@ -0,0 +1,314 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Support for message sets.
+ */
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+	"sync"
+)
+
+// errNoMessageTypeID occurs when a protocol buffer does not have a message type ID.
+// A message type ID is required for storing a protocol buffer in a message set.
+var errNoMessageTypeID = errors.New("proto does not have a message type ID")
+
+// The first two types (_MessageSet_Item and messageSet)
+// model what the protocol compiler produces for the following protocol message:
+//   message MessageSet {
+//     repeated group Item = 1 {
+//       required int32 type_id = 2;
+//       required string message = 3;
+//     };
+//   }
+// That is the MessageSet wire format. We can't use a proto to generate these
+// because that would introduce a circular dependency between it and this package.
+
+type _MessageSet_Item struct {
+	TypeId  *int32 `protobuf:"varint,2,req,name=type_id"`
+	Message []byte `protobuf:"bytes,3,req,name=message"`
+}
+
+type messageSet struct {
+	Item             []*_MessageSet_Item `protobuf:"group,1,rep"`
+	XXX_unrecognized []byte
+	// TODO: caching?
+}
+
+// Make sure messageSet is a Message.
+var _ Message = (*messageSet)(nil)
+
+// messageTypeIder is an interface satisfied by a protocol buffer type
+// that may be stored in a MessageSet.
+type messageTypeIder interface {
+	MessageTypeId() int32
+}
+
+func (ms *messageSet) find(pb Message) *_MessageSet_Item {
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return nil
+	}
+	id := mti.MessageTypeId()
+	for _, item := range ms.Item {
+		if *item.TypeId == id {
+			return item
+		}
+	}
+	return nil
+}
+
+func (ms *messageSet) Has(pb Message) bool {
+	return ms.find(pb) != nil
+}
+
+func (ms *messageSet) Unmarshal(pb Message) error {
+	if item := ms.find(pb); item != nil {
+		return Unmarshal(item.Message, pb)
+	}
+	if _, ok := pb.(messageTypeIder); !ok {
+		return errNoMessageTypeID
+	}
+	return nil // TODO: return error instead?
+}
+
+func (ms *messageSet) Marshal(pb Message) error {
+	msg, err := Marshal(pb)
+	if err != nil {
+		return err
+	}
+	if item := ms.find(pb); item != nil {
+		// reuse existing item
+		item.Message = msg
+		return nil
+	}
+
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return errNoMessageTypeID
+	}
+
+	mtid := mti.MessageTypeId()
+	ms.Item = append(ms.Item, &_MessageSet_Item{
+		TypeId:  &mtid,
+		Message: msg,
+	})
+	return nil
+}
+
+func (ms *messageSet) Reset()         { *ms = messageSet{} }
+func (ms *messageSet) String() string { return CompactTextString(ms) }
+func (*messageSet) ProtoMessage()     {}
+
+// Support for the message_set_wire_format message option.
+
+func skipVarint(buf []byte) []byte {
+	i := 0
+	for ; buf[i]&0x80 != 0; i++ {
+	}
+	return buf[i+1:]
+}
+
+// MarshalMessageSet encodes the extension map represented by m in the message set wire format.
+// It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSet(exts interface{}) ([]byte, error) {
+	return marshalMessageSet(exts, false)
+}
+
+// marshaMessageSet implements above function, with the opt to turn on / off deterministic during Marshal.
+func marshalMessageSet(exts interface{}, deterministic bool) ([]byte, error) {
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		var u marshalInfo
+		siz := u.sizeMessageSet(exts)
+		b := make([]byte, 0, siz)
+		return u.appendMessageSet(b, exts, deterministic)
+
+	case map[int32]Extension:
+		// This is an old-style extension map.
+		// Wrap it in a new-style XXX_InternalExtensions.
+		ie := XXX_InternalExtensions{
+			p: &struct {
+				mu           sync.Mutex
+				extensionMap map[int32]Extension
+			}{
+				extensionMap: exts,
+			},
+		}
+
+		var u marshalInfo
+		siz := u.sizeMessageSet(&ie)
+		b := make([]byte, 0, siz)
+		return u.appendMessageSet(b, &ie, deterministic)
+
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+}
+
+// UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
+// It is called by Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSet(buf []byte, exts interface{}) error {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m = exts.extensionsWrite()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return errors.New("proto: not an extension map")
+	}
+
+	ms := new(messageSet)
+	if err := Unmarshal(buf, ms); err != nil {
+		return err
+	}
+	for _, item := range ms.Item {
+		id := *item.TypeId
+		msg := item.Message
+
+		// Restore wire type and field number varint, plus length varint.
+		// Be careful to preserve duplicate items.
+		b := EncodeVarint(uint64(id)<<3 | WireBytes)
+		if ext, ok := m[id]; ok {
+			// Existing data; rip off the tag and length varint
+			// so we join the new data correctly.
+			// We can assume that ext.enc is set because we are unmarshaling.
+			o := ext.enc[len(b):]   // skip wire type and field number
+			_, n := DecodeVarint(o) // calculate length of length varint
+			o = o[n:]               // skip length varint
+			msg = append(o, msg...) // join old data and new data
+		}
+		b = append(b, EncodeVarint(uint64(len(msg)))...)
+		b = append(b, msg...)
+
+		m[id] = Extension{enc: b}
+	}
+	return nil
+}
+
+// MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
+// It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSetJSON(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		var mu sync.Locker
+		m, mu = exts.extensionsRead()
+		if m != nil {
+			// Keep the extensions map locked until we're done marshaling to prevent
+			// races between marshaling and unmarshaling the lazily-{en,de}coded
+			// values.
+			mu.Lock()
+			defer mu.Unlock()
+		}
+	case map[int32]Extension:
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+	var b bytes.Buffer
+	b.WriteByte('{')
+
+	// Process the map in key order for deterministic output.
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids)) // int32Slice defined in text.go
+
+	for i, id := range ids {
+		ext := m[id]
+		msd, ok := messageSetMap[id]
+		if !ok {
+			// Unknown type; we can't render it, so skip it.
+			continue
+		}
+
+		if i > 0 && b.Len() > 1 {
+			b.WriteByte(',')
+		}
+
+		fmt.Fprintf(&b, `"[%s]":`, msd.name)
+
+		x := ext.value
+		if x == nil {
+			x = reflect.New(msd.t.Elem()).Interface()
+			if err := Unmarshal(ext.enc, x.(Message)); err != nil {
+				return nil, err
+			}
+		}
+		d, err := json.Marshal(x)
+		if err != nil {
+			return nil, err
+		}
+		b.Write(d)
+	}
+	b.WriteByte('}')
+	return b.Bytes(), nil
+}
+
+// UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
+// It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSetJSON(buf []byte, exts interface{}) error {
+	// Common-case fast path.
+	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
+		return nil
+	}
+
+	// This is fairly tricky, and it's not clear that it is needed.
+	return errors.New("TODO: UnmarshalMessageSetJSON not yet implemented")
+}
+
+// A global registry of types that can be used in a MessageSet.
+
+var messageSetMap = make(map[int32]messageSetDesc)
+
+type messageSetDesc struct {
+	t    reflect.Type // pointer to struct
+	name string
+}
+
+// RegisterMessageSetType is called from the generated code.
+func RegisterMessageSetType(m Message, fieldNum int32, name string) {
+	messageSetMap[fieldNum] = messageSetDesc{
+		t:    reflect.TypeOf(m),
+		name: name,
+	}
+}

vendor/github.com/golang/protobuf/proto/pointer_reflect.go

@@ -0,0 +1,357 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build purego appengine js
+
+// This file contains an implementation of proto field accesses using package reflect.
+// It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
+// be used on App Engine.
+
+package proto
+
+import (
+	"reflect"
+	"sync"
+)
+
+const unsafeAllowed = false
+
+// A field identifies a field in a struct, accessible from a pointer.
+// In this implementation, a field is identified by the sequence of field indices
+// passed to reflect's FieldByIndex.
+type field []int
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return f.Index
+}
+
+// invalidField is an invalid field identifier.
+var invalidField = field(nil)
+
+// zeroField is a noop when calling pointer.offset.
+var zeroField = field([]int{})
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool { return f != nil }
+
+// The pointer type is for the table-driven decoder.
+// The implementation here uses a reflect.Value of pointer type to
+// create a generic pointer. In pointer_unsafe.go we use unsafe
+// instead of reflect to implement the same (but faster) interface.
+type pointer struct {
+	v reflect.Value
+}
+
+// toPointer converts an interface of pointer type to a pointer
+// that points to the same target.
+func toPointer(i *Message) pointer {
+	return pointer{v: reflect.ValueOf(*i)}
+}
+
+// toAddrPointer converts an interface to a pointer that points to
+// the interface data.
+func toAddrPointer(i *interface{}, isptr bool) pointer {
+	v := reflect.ValueOf(*i)
+	u := reflect.New(v.Type())
+	u.Elem().Set(v)
+	return pointer{v: u}
+}
+
+// valToPointer converts v to a pointer.  v must be of pointer type.
+func valToPointer(v reflect.Value) pointer {
+	return pointer{v: v}
+}
+
+// offset converts from a pointer to a structure to a pointer to
+// one of its fields.
+func (p pointer) offset(f field) pointer {
+	return pointer{v: p.v.Elem().FieldByIndex(f).Addr()}
+}
+
+func (p pointer) isNil() bool {
+	return p.v.IsNil()
+}
+
+// grow updates the slice s in place to make it one element longer.
+// s must be addressable.
+// Returns the (addressable) new element.
+func grow(s reflect.Value) reflect.Value {
+	n, m := s.Len(), s.Cap()
+	if n < m {
+		s.SetLen(n + 1)
+	} else {
+		s.Set(reflect.Append(s, reflect.Zero(s.Type().Elem())))
+	}
+	return s.Index(n)
+}
+
+func (p pointer) toInt64() *int64 {
+	return p.v.Interface().(*int64)
+}
+func (p pointer) toInt64Ptr() **int64 {
+	return p.v.Interface().(**int64)
+}
+func (p pointer) toInt64Slice() *[]int64 {
+	return p.v.Interface().(*[]int64)
+}
+
+var int32ptr = reflect.TypeOf((*int32)(nil))
+
+func (p pointer) toInt32() *int32 {
+	return p.v.Convert(int32ptr).Interface().(*int32)
+}
+
+// The toInt32Ptr/Slice methods don't work because of enums.
+// Instead, we must use set/get methods for the int32ptr/slice case.
+/*
+	func (p pointer) toInt32Ptr() **int32 {
+		return p.v.Interface().(**int32)
+}
+	func (p pointer) toInt32Slice() *[]int32 {
+		return p.v.Interface().(*[]int32)
+}
+*/
+func (p pointer) getInt32Ptr() *int32 {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		return p.v.Elem().Interface().(*int32)
+	}
+	// an enum
+	return p.v.Elem().Convert(int32PtrType).Interface().(*int32)
+}
+func (p pointer) setInt32Ptr(v int32) {
+	// Allocate value in a *int32. Possibly convert that to a *enum.
+	// Then assign it to a **int32 or **enum.
+	// Note: we can convert *int32 to *enum, but we can't convert
+	// **int32 to **enum!
+	p.v.Elem().Set(reflect.ValueOf(&v).Convert(p.v.Type().Elem()))
+}
+
+// getInt32Slice copies []int32 from p as a new slice.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) getInt32Slice() []int32 {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		return p.v.Elem().Interface().([]int32)
+	}
+	// an enum
+	// Allocate a []int32, then assign []enum's values into it.
+	// Note: we can't convert []enum to []int32.
+	slice := p.v.Elem()
+	s := make([]int32, slice.Len())
+	for i := 0; i < slice.Len(); i++ {
+		s[i] = int32(slice.Index(i).Int())
+	}
+	return s
+}
+
+// setInt32Slice copies []int32 into p as a new slice.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) setInt32Slice(v []int32) {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		p.v.Elem().Set(reflect.ValueOf(v))
+		return
+	}
+	// an enum
+	// Allocate a []enum, then assign []int32's values into it.
+	// Note: we can't convert []enum to []int32.
+	slice := reflect.MakeSlice(p.v.Type().Elem(), len(v), cap(v))
+	for i, x := range v {
+		slice.Index(i).SetInt(int64(x))
+	}
+	p.v.Elem().Set(slice)
+}
+func (p pointer) appendInt32Slice(v int32) {
+	grow(p.v.Elem()).SetInt(int64(v))
+}
+
+func (p pointer) toUint64() *uint64 {
+	return p.v.Interface().(*uint64)
+}
+func (p pointer) toUint64Ptr() **uint64 {
+	return p.v.Interface().(**uint64)
+}
+func (p pointer) toUint64Slice() *[]uint64 {
+	return p.v.Interface().(*[]uint64)
+}
+func (p pointer) toUint32() *uint32 {
+	return p.v.Interface().(*uint32)
+}
+func (p pointer) toUint32Ptr() **uint32 {
+	return p.v.Interface().(**uint32)
+}
+func (p pointer) toUint32Slice() *[]uint32 {
+	return p.v.Interface().(*[]uint32)
+}
+func (p pointer) toBool() *bool {
+	return p.v.Interface().(*bool)
+}
+func (p pointer) toBoolPtr() **bool {
+	return p.v.Interface().(**bool)
+}
+func (p pointer) toBoolSlice() *[]bool {
+	return p.v.Interface().(*[]bool)
+}
+func (p pointer) toFloat64() *float64 {
+	return p.v.Interface().(*float64)
+}
+func (p pointer) toFloat64Ptr() **float64 {
+	return p.v.Interface().(**float64)
+}
+func (p pointer) toFloat64Slice() *[]float64 {
+	return p.v.Interface().(*[]float64)
+}
+func (p pointer) toFloat32() *float32 {
+	return p.v.Interface().(*float32)
+}
+func (p pointer) toFloat32Ptr() **float32 {
+	return p.v.Interface().(**float32)
+}
+func (p pointer) toFloat32Slice() *[]float32 {
+	return p.v.Interface().(*[]float32)
+}
+func (p pointer) toString() *string {
+	return p.v.Interface().(*string)
+}
+func (p pointer) toStringPtr() **string {
+	return p.v.Interface().(**string)
+}
+func (p pointer) toStringSlice() *[]string {
+	return p.v.Interface().(*[]string)
+}
+func (p pointer) toBytes() *[]byte {
+	return p.v.Interface().(*[]byte)
+}
+func (p pointer) toBytesSlice() *[][]byte {
+	return p.v.Interface().(*[][]byte)
+}
+func (p pointer) toExtensions() *XXX_InternalExtensions {
+	return p.v.Interface().(*XXX_InternalExtensions)
+}
+func (p pointer) toOldExtensions() *map[int32]Extension {
+	return p.v.Interface().(*map[int32]Extension)
+}
+func (p pointer) getPointer() pointer {
+	return pointer{v: p.v.Elem()}
+}
+func (p pointer) setPointer(q pointer) {
+	p.v.Elem().Set(q.v)
+}
+func (p pointer) appendPointer(q pointer) {
+	grow(p.v.Elem()).Set(q.v)
+}
+
+// getPointerSlice copies []*T from p as a new []pointer.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) getPointerSlice() []pointer {
+	if p.v.IsNil() {
+		return nil
+	}
+	n := p.v.Elem().Len()
+	s := make([]pointer, n)
+	for i := 0; i < n; i++ {
+		s[i] = pointer{v: p.v.Elem().Index(i)}
+	}
+	return s
+}
+
+// setPointerSlice copies []pointer into p as a new []*T.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) setPointerSlice(v []pointer) {
+	if v == nil {
+		p.v.Elem().Set(reflect.New(p.v.Elem().Type()).Elem())
+		return
+	}
+	s := reflect.MakeSlice(p.v.Elem().Type(), 0, len(v))
+	for _, p := range v {
+		s = reflect.Append(s, p.v)
+	}
+	p.v.Elem().Set(s)
+}
+
+// getInterfacePointer returns a pointer that points to the
+// interface data of the interface pointed by p.
+func (p pointer) getInterfacePointer() pointer {
+	if p.v.Elem().IsNil() {
+		return pointer{v: p.v.Elem()}
+	}
+	return pointer{v: p.v.Elem().Elem().Elem().Field(0).Addr()} // *interface -> interface -> *struct -> struct
+}
+
+func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
+	// TODO: check that p.v.Type().Elem() == t?
+	return p.v
+}
+
+func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
+}
+func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
+}
+func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
+}
+func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
+}
+
+var atomicLock sync.Mutex

vendor/github.com/golang/protobuf/proto/pointer_unsafe.go

@@ -0,0 +1,308 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build !purego,!appengine,!js
+
+// This file contains the implementation of the proto field accesses using package unsafe.
+
+package proto
+
+import (
+	"reflect"
+	"sync/atomic"
+	"unsafe"
+)
+
+const unsafeAllowed = true
+
+// A field identifies a field in a struct, accessible from a pointer.
+// In this implementation, a field is identified by its byte offset from the start of the struct.
+type field uintptr
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return field(f.Offset)
+}
+
+// invalidField is an invalid field identifier.
+const invalidField = ^field(0)
+
+// zeroField is a noop when calling pointer.offset.
+const zeroField = field(0)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool {
+	return f != invalidField
+}
+
+// The pointer type below is for the new table-driven encoder/decoder.
+// The implementation here uses unsafe.Pointer to create a generic pointer.
+// In pointer_reflect.go we use reflect instead of unsafe to implement
+// the same (but slower) interface.
+type pointer struct {
+	p unsafe.Pointer
+}
+
+// size of pointer
+var ptrSize = unsafe.Sizeof(uintptr(0))
+
+// toPointer converts an interface of pointer type to a pointer
+// that points to the same target.
+func toPointer(i *Message) pointer {
+	// Super-tricky - read pointer out of data word of interface value.
+	// Saves ~25ns over the equivalent:
+	// return valToPointer(reflect.ValueOf(*i))
+	return pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
+}
+
+// toAddrPointer converts an interface to a pointer that points to
+// the interface data.
+func toAddrPointer(i *interface{}, isptr bool) pointer {
+	// Super-tricky - read or get the address of data word of interface value.
+	if isptr {
+		// The interface is of pointer type, thus it is a direct interface.
+		// The data word is the pointer data itself. We take its address.
+		return pointer{p: unsafe.Pointer(uintptr(unsafe.Pointer(i)) + ptrSize)}
+	}
+	// The interface is not of pointer type. The data word is the pointer
+	// to the data.
+	return pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
+}
+
+// valToPointer converts v to a pointer. v must be of pointer type.
+func valToPointer(v reflect.Value) pointer {
+	return pointer{p: unsafe.Pointer(v.Pointer())}
+}
+
+// offset converts from a pointer to a structure to a pointer to
+// one of its fields.
+func (p pointer) offset(f field) pointer {
+	// For safety, we should panic if !f.IsValid, however calling panic causes
+	// this to no longer be inlineable, which is a serious performance cost.
+	/*
+		if !f.IsValid() {
+			panic("invalid field")
+		}
+	*/
+	return pointer{p: unsafe.Pointer(uintptr(p.p) + uintptr(f))}
+}
+
+func (p pointer) isNil() bool {
+	return p.p == nil
+}
+
+func (p pointer) toInt64() *int64 {
+	return (*int64)(p.p)
+}
+func (p pointer) toInt64Ptr() **int64 {
+	return (**int64)(p.p)
+}
+func (p pointer) toInt64Slice() *[]int64 {
+	return (*[]int64)(p.p)
+}
+func (p pointer) toInt32() *int32 {
+	return (*int32)(p.p)
+}
+
+// See pointer_reflect.go for why toInt32Ptr/Slice doesn't exist.
+/*
+	func (p pointer) toInt32Ptr() **int32 {
+		return (**int32)(p.p)
+	}
+	func (p pointer) toInt32Slice() *[]int32 {
+		return (*[]int32)(p.p)
+	}
+*/
+func (p pointer) getInt32Ptr() *int32 {
+	return *(**int32)(p.p)
+}
+func (p pointer) setInt32Ptr(v int32) {
+	*(**int32)(p.p) = &v
+}
+
+// getInt32Slice loads a []int32 from p.
+// The value returned is aliased with the original slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) getInt32Slice() []int32 {
+	return *(*[]int32)(p.p)
+}
+
+// setInt32Slice stores a []int32 to p.
+// The value set is aliased with the input slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) setInt32Slice(v []int32) {
+	*(*[]int32)(p.p) = v
+}
+
+// TODO: Can we get rid of appendInt32Slice and use setInt32Slice instead?
+func (p pointer) appendInt32Slice(v int32) {
+	s := (*[]int32)(p.p)
+	*s = append(*s, v)
+}
+
+func (p pointer) toUint64() *uint64 {
+	return (*uint64)(p.p)
+}
+func (p pointer) toUint64Ptr() **uint64 {
+	return (**uint64)(p.p)
+}
+func (p pointer) toUint64Slice() *[]uint64 {
+	return (*[]uint64)(p.p)
+}
+func (p pointer) toUint32() *uint32 {
+	return (*uint32)(p.p)
+}
+func (p pointer) toUint32Ptr() **uint32 {
+	return (**uint32)(p.p)
+}
+func (p pointer) toUint32Slice() *[]uint32 {
+	return (*[]uint32)(p.p)
+}
+func (p pointer) toBool() *bool {
+	return (*bool)(p.p)
+}
+func (p pointer) toBoolPtr() **bool {
+	return (**bool)(p.p)
+}
+func (p pointer) toBoolSlice() *[]bool {
+	return (*[]bool)(p.p)
+}
+func (p pointer) toFloat64() *float64 {
+	return (*float64)(p.p)
+}
+func (p pointer) toFloat64Ptr() **float64 {
+	return (**float64)(p.p)
+}
+func (p pointer) toFloat64Slice() *[]float64 {
+	return (*[]float64)(p.p)
+}
+func (p pointer) toFloat32() *float32 {
+	return (*float32)(p.p)
+}
+func (p pointer) toFloat32Ptr() **float32 {
+	return (**float32)(p.p)
+}
+func (p pointer) toFloat32Slice() *[]float32 {
+	return (*[]float32)(p.p)
+}
+func (p pointer) toString() *string {
+	return (*string)(p.p)
+}
+func (p pointer) toStringPtr() **string {
+	return (**string)(p.p)
+}
+func (p pointer) toStringSlice() *[]string {
+	return (*[]string)(p.p)
+}
+func (p pointer) toBytes() *[]byte {
+	return (*[]byte)(p.p)
+}
+func (p pointer) toBytesSlice() *[][]byte {
+	return (*[][]byte)(p.p)
+}
+func (p pointer) toExtensions() *XXX_InternalExtensions {
+	return (*XXX_InternalExtensions)(p.p)
+}
+func (p pointer) toOldExtensions() *map[int32]Extension {
+	return (*map[int32]Extension)(p.p)
+}
+
+// getPointerSlice loads []*T from p as a []pointer.
+// The value returned is aliased with the original slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) getPointerSlice() []pointer {
+	// Super-tricky - p should point to a []*T where T is a
+	// message type. We load it as []pointer.
+	return *(*[]pointer)(p.p)
+}
+
+// setPointerSlice stores []pointer into p as a []*T.
+// The value set is aliased with the input slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) setPointerSlice(v []pointer) {
+	// Super-tricky - p should point to a []*T where T is a
+	// message type. We store it as []pointer.
+	*(*[]pointer)(p.p) = v
+}
+
+// getPointer loads the pointer at p and returns it.
+func (p pointer) getPointer() pointer {
+	return pointer{p: *(*unsafe.Pointer)(p.p)}
+}
+
+// setPointer stores the pointer q at p.
+func (p pointer) setPointer(q pointer) {
+	*(*unsafe.Pointer)(p.p) = q.p
+}
+
+// append q to the slice pointed to by p.
+func (p pointer) appendPointer(q pointer) {
+	s := (*[]unsafe.Pointer)(p.p)
+	*s = append(*s, q.p)
+}
+
+// getInterfacePointer returns a pointer that points to the
+// interface data of the interface pointed by p.
+func (p pointer) getInterfacePointer() pointer {
+	// Super-tricky - read pointer out of data word of interface value.
+	return pointer{p: (*(*[2]unsafe.Pointer)(p.p))[1]}
+}
+
+// asPointerTo returns a reflect.Value that is a pointer to an
+// object of type t stored at p.
+func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
+	return reflect.NewAt(t, p.p)
+}
+
+func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
+	return (*unmarshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
+	return (*marshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
+	return (*mergeInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
+	return (*discardInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}

vendor/github.com/golang/protobuf/proto/properties.go

@@ -0,0 +1,544 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+const debug bool = false
+
+// Constants that identify the encoding of a value on the wire.
+const (
+	WireVarint     = 0
+	WireFixed64    = 1
+	WireBytes      = 2
+	WireStartGroup = 3
+	WireEndGroup   = 4
+	WireFixed32    = 5
+)
+
+// tagMap is an optimization over map[int]int for typical protocol buffer
+// use-cases. Encoded protocol buffers are often in tag order with small tag
+// numbers.
+type tagMap struct {
+	fastTags []int
+	slowTags map[int]int
+}
+
+// tagMapFastLimit is the upper bound on the tag number that will be stored in
+// the tagMap slice rather than its map.
+const tagMapFastLimit = 1024
+
+func (p *tagMap) get(t int) (int, bool) {
+	if t > 0 && t < tagMapFastLimit {
+		if t >= len(p.fastTags) {
+			return 0, false
+		}
+		fi := p.fastTags[t]
+		return fi, fi >= 0
+	}
+	fi, ok := p.slowTags[t]
+	return fi, ok
+}
+
+func (p *tagMap) put(t int, fi int) {
+	if t > 0 && t < tagMapFastLimit {
+		for len(p.fastTags) < t+1 {
+			p.fastTags = append(p.fastTags, -1)
+		}
+		p.fastTags[t] = fi
+		return
+	}
+	if p.slowTags == nil {
+		p.slowTags = make(map[int]int)
+	}
+	p.slowTags[t] = fi
+}
+
+// StructProperties represents properties for all the fields of a struct.
+// decoderTags and decoderOrigNames should only be used by the decoder.
+type StructProperties struct {
+	Prop             []*Properties  // properties for each field
+	reqCount         int            // required count
+	decoderTags      tagMap         // map from proto tag to struct field number
+	decoderOrigNames map[string]int // map from original name to struct field number
+	order            []int          // list of struct field numbers in tag order
+
+	// OneofTypes contains information about the oneof fields in this message.
+	// It is keyed by the original name of a field.
+	OneofTypes map[string]*OneofProperties
+}
+
+// OneofProperties represents information about a specific field in a oneof.
+type OneofProperties struct {
+	Type  reflect.Type // pointer to generated struct type for this oneof field
+	Field int          // struct field number of the containing oneof in the message
+	Prop  *Properties
+}
+
+// Implement the sorting interface so we can sort the fields in tag order, as recommended by the spec.
+// See encode.go, (*Buffer).enc_struct.
+
+func (sp *StructProperties) Len() int { return len(sp.order) }
+func (sp *StructProperties) Less(i, j int) bool {
+	return sp.Prop[sp.order[i]].Tag < sp.Prop[sp.order[j]].Tag
+}
+func (sp *StructProperties) Swap(i, j int) { sp.order[i], sp.order[j] = sp.order[j], sp.order[i] }
+
+// Properties represents the protocol-specific behavior of a single struct field.
+type Properties struct {
+	Name     string // name of the field, for error messages
+	OrigName string // original name before protocol compiler (always set)
+	JSONName string // name to use for JSON; determined by protoc
+	Wire     string
+	WireType int
+	Tag      int
+	Required bool
+	Optional bool
+	Repeated bool
+	Packed   bool   // relevant for repeated primitives only
+	Enum     string // set for enum types only
+	proto3   bool   // whether this is known to be a proto3 field
+	oneof    bool   // whether this is a oneof field
+
+	Default    string // default value
+	HasDefault bool   // whether an explicit default was provided
+
+	stype reflect.Type      // set for struct types only
+	sprop *StructProperties // set for struct types only
+
+	mtype      reflect.Type // set for map types only
+	MapKeyProp *Properties  // set for map types only
+	MapValProp *Properties  // set for map types only
+}
+
+// String formats the properties in the protobuf struct field tag style.
+func (p *Properties) String() string {
+	s := p.Wire
+	s += ","
+	s += strconv.Itoa(p.Tag)
+	if p.Required {
+		s += ",req"
+	}
+	if p.Optional {
+		s += ",opt"
+	}
+	if p.Repeated {
+		s += ",rep"
+	}
+	if p.Packed {
+		s += ",packed"
+	}
+	s += ",name=" + p.OrigName
+	if p.JSONName != p.OrigName {
+		s += ",json=" + p.JSONName
+	}
+	if p.proto3 {
+		s += ",proto3"
+	}
+	if p.oneof {
+		s += ",oneof"
+	}
+	if len(p.Enum) > 0 {
+		s += ",enum=" + p.Enum
+	}
+	if p.HasDefault {
+		s += ",def=" + p.Default
+	}
+	return s
+}
+
+// Parse populates p by parsing a string in the protobuf struct field tag style.
+func (p *Properties) Parse(s string) {
+	// "bytes,49,opt,name=foo,def=hello!"
+	fields := strings.Split(s, ",") // breaks def=, but handled below.
+	if len(fields) < 2 {
+		fmt.Fprintf(os.Stderr, "proto: tag has too few fields: %q\n", s)
+		return
+	}
+
+	p.Wire = fields[0]
+	switch p.Wire {
+	case "varint":
+		p.WireType = WireVarint
+	case "fixed32":
+		p.WireType = WireFixed32
+	case "fixed64":
+		p.WireType = WireFixed64
+	case "zigzag32":
+		p.WireType = WireVarint
+	case "zigzag64":
+		p.WireType = WireVarint
+	case "bytes", "group":
+		p.WireType = WireBytes
+		// no numeric converter for non-numeric types
+	default:
+		fmt.Fprintf(os.Stderr, "proto: tag has unknown wire type: %q\n", s)
+		return
+	}
+
+	var err error
+	p.Tag, err = strconv.Atoi(fields[1])
+	if err != nil {
+		return
+	}
+
+outer:
+	for i := 2; i < len(fields); i++ {
+		f := fields[i]
+		switch {
+		case f == "req":
+			p.Required = true
+		case f == "opt":
+			p.Optional = true
+		case f == "rep":
+			p.Repeated = true
+		case f == "packed":
+			p.Packed = true
+		case strings.HasPrefix(f, "name="):
+			p.OrigName = f[5:]
+		case strings.HasPrefix(f, "json="):
+			p.JSONName = f[5:]
+		case strings.HasPrefix(f, "enum="):
+			p.Enum = f[5:]
+		case f == "proto3":
+			p.proto3 = true
+		case f == "oneof":
+			p.oneof = true
+		case strings.HasPrefix(f, "def="):
+			p.HasDefault = true
+			p.Default = f[4:] // rest of string
+			if i+1 < len(fields) {
+				// Commas aren't escaped, and def is always last.
+				p.Default += "," + strings.Join(fields[i+1:], ",")
+				break outer
+			}
+		}
+	}
+}
+
+var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem()
+
+// setFieldProps initializes the field properties for submessages and maps.
+func (p *Properties) setFieldProps(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
+	switch t1 := typ; t1.Kind() {
+	case reflect.Ptr:
+		if t1.Elem().Kind() == reflect.Struct {
+			p.stype = t1.Elem()
+		}
+
+	case reflect.Slice:
+		if t2 := t1.Elem(); t2.Kind() == reflect.Ptr && t2.Elem().Kind() == reflect.Struct {
+			p.stype = t2.Elem()
+		}
+
+	case reflect.Map:
+		p.mtype = t1
+		p.MapKeyProp = &Properties{}
+		p.MapKeyProp.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
+		p.MapValProp = &Properties{}
+		vtype := p.mtype.Elem()
+		if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice {
+			// The value type is not a message (*T) or bytes ([]byte),
+			// so we need encoders for the pointer to this type.
+			vtype = reflect.PtrTo(vtype)
+		}
+		p.MapValProp.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
+	}
+
+	if p.stype != nil {
+		if lockGetProp {
+			p.sprop = GetProperties(p.stype)
+		} else {
+			p.sprop = getPropertiesLocked(p.stype)
+		}
+	}
+}
+
+var (
+	marshalerType = reflect.TypeOf((*Marshaler)(nil)).Elem()
+)
+
+// Init populates the properties from a protocol buffer struct tag.
+func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) {
+	p.init(typ, name, tag, f, true)
+}
+
+func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructField, lockGetProp bool) {
+	// "bytes,49,opt,def=hello!"
+	p.Name = name
+	p.OrigName = name
+	if tag == "" {
+		return
+	}
+	p.Parse(tag)
+	p.setFieldProps(typ, f, lockGetProp)
+}
+
+var (
+	propertiesMu  sync.RWMutex
+	propertiesMap = make(map[reflect.Type]*StructProperties)
+)
+
+// GetProperties returns the list of properties for the type represented by t.
+// t must represent a generated struct type of a protocol message.
+func GetProperties(t reflect.Type) *StructProperties {
+	if t.Kind() != reflect.Struct {
+		panic("proto: type must have kind struct")
+	}
+
+	// Most calls to GetProperties in a long-running program will be
+	// retrieving details for types we have seen before.
+	propertiesMu.RLock()
+	sprop, ok := propertiesMap[t]
+	propertiesMu.RUnlock()
+	if ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return sprop
+	}
+
+	propertiesMu.Lock()
+	sprop = getPropertiesLocked(t)
+	propertiesMu.Unlock()
+	return sprop
+}
+
+// getPropertiesLocked requires that propertiesMu is held.
+func getPropertiesLocked(t reflect.Type) *StructProperties {
+	if prop, ok := propertiesMap[t]; ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return prop
+	}
+	if collectStats {
+		stats.Cmiss++
+	}
+
+	prop := new(StructProperties)
+	// in case of recursive protos, fill this in now.
+	propertiesMap[t] = prop
+
+	// build properties
+	prop.Prop = make([]*Properties, t.NumField())
+	prop.order = make([]int, t.NumField())
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		p := new(Properties)
+		name := f.Name
+		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
+
+		oneof := f.Tag.Get("protobuf_oneof") // special case
+		if oneof != "" {
+			// Oneof fields don't use the traditional protobuf tag.
+			p.OrigName = oneof
+		}
+		prop.Prop[i] = p
+		prop.order[i] = i
+		if debug {
+			print(i, " ", f.Name, " ", t.String(), " ")
+			if p.Tag > 0 {
+				print(p.String())
+			}
+			print("\n")
+		}
+	}
+
+	// Re-order prop.order.
+	sort.Sort(prop)
+
+	type oneofMessage interface {
+		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{})
+	}
+	if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok {
+		var oots []interface{}
+		_, _, _, oots = om.XXX_OneofFuncs()
+
+		// Interpret oneof metadata.
+		prop.OneofTypes = make(map[string]*OneofProperties)
+		for _, oot := range oots {
+			oop := &OneofProperties{
+				Type: reflect.ValueOf(oot).Type(), // *T
+				Prop: new(Properties),
+			}
+			sft := oop.Type.Elem().Field(0)
+			oop.Prop.Name = sft.Name
+			oop.Prop.Parse(sft.Tag.Get("protobuf"))
+			// There will be exactly one interface field that
+			// this new value is assignable to.
+			for i := 0; i < t.NumField(); i++ {
+				f := t.Field(i)
+				if f.Type.Kind() != reflect.Interface {
+					continue
+				}
+				if !oop.Type.AssignableTo(f.Type) {
+					continue
+				}
+				oop.Field = i
+				break
+			}
+			prop.OneofTypes[oop.Prop.OrigName] = oop
+		}
+	}
+
+	// build required counts
+	// build tags
+	reqCount := 0
+	prop.decoderOrigNames = make(map[string]int)
+	for i, p := range prop.Prop {
+		if strings.HasPrefix(p.Name, "XXX_") {
+			// Internal fields should not appear in tags/origNames maps.
+			// They are handled specially when encoding and decoding.
+			continue
+		}
+		if p.Required {
+			reqCount++
+		}
+		prop.decoderTags.put(p.Tag, i)
+		prop.decoderOrigNames[p.OrigName] = i
+	}
+	prop.reqCount = reqCount
+
+	return prop
+}
+
+// A global registry of enum types.
+// The generated code will register the generated maps by calling RegisterEnum.
+
+var enumValueMaps = make(map[string]map[string]int32)
+
+// RegisterEnum is called from the generated code to install the enum descriptor
+// maps into the global table to aid parsing text format protocol buffers.
+func RegisterEnum(typeName string, unusedNameMap map[int32]string, valueMap map[string]int32) {
+	if _, ok := enumValueMaps[typeName]; ok {
+		panic("proto: duplicate enum registered: " + typeName)
+	}
+	enumValueMaps[typeName] = valueMap
+}
+
+// EnumValueMap returns the mapping from names to integers of the
+// enum type enumType, or a nil if not found.
+func EnumValueMap(enumType string) map[string]int32 {
+	return enumValueMaps[enumType]
+}
+
+// A registry of all linked message types.
+// The string is a fully-qualified proto name ("pkg.Message").
+var (
+	protoTypedNils = make(map[string]Message)      // a map from proto names to typed nil pointers
+	protoMapTypes  = make(map[string]reflect.Type) // a map from proto names to map types
+	revProtoTypes  = make(map[reflect.Type]string)
+)
+
+// RegisterType is called from generated code and maps from the fully qualified
+// proto name to the type (pointer to struct) of the protocol buffer.
+func RegisterType(x Message, name string) {
+	if _, ok := protoTypedNils[name]; ok {
+		// TODO: Some day, make this a panic.
+		log.Printf("proto: duplicate proto type registered: %s", name)
+		return
+	}
+	t := reflect.TypeOf(x)
+	if v := reflect.ValueOf(x); v.Kind() == reflect.Ptr && v.Pointer() == 0 {
+		// Generated code always calls RegisterType with nil x.
+		// This check is just for extra safety.
+		protoTypedNils[name] = x
+	} else {
+		protoTypedNils[name] = reflect.Zero(t).Interface().(Message)
+	}
+	revProtoTypes[t] = name
+}
+
+// RegisterMapType is called from generated code and maps from the fully qualified
+// proto name to the native map type of the proto map definition.
+func RegisterMapType(x interface{}, name string) {
+	if reflect.TypeOf(x).Kind() != reflect.Map {
+		panic(fmt.Sprintf("RegisterMapType(%T, %q); want map", x, name))
+	}
+	if _, ok := protoMapTypes[name]; ok {
+		log.Printf("proto: duplicate proto type registered: %s", name)
+		return
+	}
+	t := reflect.TypeOf(x)
+	protoMapTypes[name] = t
+	revProtoTypes[t] = name
+}
+
+// MessageName returns the fully-qualified proto name for the given message type.
+func MessageName(x Message) string {
+	type xname interface {
+		XXX_MessageName() string
+	}
+	if m, ok := x.(xname); ok {
+		return m.XXX_MessageName()
+	}
+	return revProtoTypes[reflect.TypeOf(x)]
+}
+
+// MessageType returns the message type (pointer to struct) for a named message.
+// The type is not guaranteed to implement proto.Message if the name refers to a
+// map entry.
+func MessageType(name string) reflect.Type {
+	if t, ok := protoTypedNils[name]; ok {
+		return reflect.TypeOf(t)
+	}
+	return protoMapTypes[name]
+}
+
+// A registry of all linked proto files.
+var (
+	protoFiles = make(map[string][]byte) // file name => fileDescriptor
+)
+
+// RegisterFile is called from generated code and maps from the
+// full file name of a .proto file to its compressed FileDescriptorProto.
+func RegisterFile(filename string, fileDescriptor []byte) {
+	protoFiles[filename] = fileDescriptor
+}
+
+// FileDescriptor returns the compressed FileDescriptorProto for a .proto file.
+func FileDescriptor(filename string) []byte { return protoFiles[filename] }

vendor/github.com/golang/protobuf/proto/table_merge.go

@@ -0,0 +1,654 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2016 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+// Merge merges the src message into dst.
+// This assumes that dst and src of the same type and are non-nil.
+func (a *InternalMessageInfo) Merge(dst, src Message) {
+	mi := atomicLoadMergeInfo(&a.merge)
+	if mi == nil {
+		mi = getMergeInfo(reflect.TypeOf(dst).Elem())
+		atomicStoreMergeInfo(&a.merge, mi)
+	}
+	mi.merge(toPointer(&dst), toPointer(&src))
+}
+
+type mergeInfo struct {
+	typ reflect.Type
+
+	initialized int32 // 0: only typ is valid, 1: everything is valid
+	lock        sync.Mutex
+
+	fields       []mergeFieldInfo
+	unrecognized field // Offset of XXX_unrecognized
+}
+
+type mergeFieldInfo struct {
+	field field // Offset of field, guaranteed to be valid
+
+	// isPointer reports whether the value in the field is a pointer.
+	// This is true for the following situations:
+	//	* Pointer to struct
+	//	* Pointer to basic type (proto2 only)
+	//	* Slice (first value in slice header is a pointer)
+	//	* String (first value in string header is a pointer)
+	isPointer bool
+
+	// basicWidth reports the width of the field assuming that it is directly
+	// embedded in the struct (as is the case for basic types in proto3).
+	// The possible values are:
+	// 	0: invalid
+	//	1: bool
+	//	4: int32, uint32, float32
+	//	8: int64, uint64, float64
+	basicWidth int
+
+	// Where dst and src are pointers to the types being merged.
+	merge func(dst, src pointer)
+}
+
+var (
+	mergeInfoMap  = map[reflect.Type]*mergeInfo{}
+	mergeInfoLock sync.Mutex
+)
+
+func getMergeInfo(t reflect.Type) *mergeInfo {
+	mergeInfoLock.Lock()
+	defer mergeInfoLock.Unlock()
+	mi := mergeInfoMap[t]
+	if mi == nil {
+		mi = &mergeInfo{typ: t}
+		mergeInfoMap[t] = mi
+	}
+	return mi
+}
+
+// merge merges src into dst assuming they are both of type *mi.typ.
+func (mi *mergeInfo) merge(dst, src pointer) {
+	if dst.isNil() {
+		panic("proto: nil destination")
+	}
+	if src.isNil() {
+		return // Nothing to do.
+	}
+
+	if atomic.LoadInt32(&mi.initialized) == 0 {
+		mi.computeMergeInfo()
+	}
+
+	for _, fi := range mi.fields {
+		sfp := src.offset(fi.field)
+
+		// As an optimization, we can avoid the merge function call cost
+		// if we know for sure that the source will have no effect
+		// by checking if it is the zero value.
+		if unsafeAllowed {
+			if fi.isPointer && sfp.getPointer().isNil() { // Could be slice or string
+				continue
+			}
+			if fi.basicWidth > 0 {
+				switch {
+				case fi.basicWidth == 1 && !*sfp.toBool():
+					continue
+				case fi.basicWidth == 4 && *sfp.toUint32() == 0:
+					continue
+				case fi.basicWidth == 8 && *sfp.toUint64() == 0:
+					continue
+				}
+			}
+		}
+
+		dfp := dst.offset(fi.field)
+		fi.merge(dfp, sfp)
+	}
+
+	// TODO: Make this faster?
+	out := dst.asPointerTo(mi.typ).Elem()
+	in := src.asPointerTo(mi.typ).Elem()
+	if emIn, err := extendable(in.Addr().Interface()); err == nil {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
+	}
+
+	if mi.unrecognized.IsValid() {
+		if b := *src.offset(mi.unrecognized).toBytes(); len(b) > 0 {
+			*dst.offset(mi.unrecognized).toBytes() = append([]byte(nil), b...)
+		}
+	}
+}
+
+func (mi *mergeInfo) computeMergeInfo() {
+	mi.lock.Lock()
+	defer mi.lock.Unlock()
+	if mi.initialized != 0 {
+		return
+	}
+	t := mi.typ
+	n := t.NumField()
+
+	props := GetProperties(t)
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+
+		mfi := mergeFieldInfo{field: toField(&f)}
+		tf := f.Type
+
+		// As an optimization, we can avoid the merge function call cost
+		// if we know for sure that the source will have no effect
+		// by checking if it is the zero value.
+		if unsafeAllowed {
+			switch tf.Kind() {
+			case reflect.Ptr, reflect.Slice, reflect.String:
+				// As a special case, we assume slices and strings are pointers
+				// since we know that the first field in the SliceSlice or
+				// StringHeader is a data pointer.
+				mfi.isPointer = true
+			case reflect.Bool:
+				mfi.basicWidth = 1
+			case reflect.Int32, reflect.Uint32, reflect.Float32:
+				mfi.basicWidth = 4
+			case reflect.Int64, reflect.Uint64, reflect.Float64:
+				mfi.basicWidth = 8
+			}
+		}
+
+		// Unwrap tf to get at its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic("both pointer and slice for basic type in " + tf.Name())
+		}
+
+		switch tf.Kind() {
+		case reflect.Int32:
+			switch {
+			case isSlice: // E.g., []int32
+				mfi.merge = func(dst, src pointer) {
+					// NOTE: toInt32Slice is not defined (see pointer_reflect.go).
+					/*
+						sfsp := src.toInt32Slice()
+						if *sfsp != nil {
+							dfsp := dst.toInt32Slice()
+							*dfsp = append(*dfsp, *sfsp...)
+							if *dfsp == nil {
+								*dfsp = []int64{}
+							}
+						}
+					*/
+					sfs := src.getInt32Slice()
+					if sfs != nil {
+						dfs := dst.getInt32Slice()
+						dfs = append(dfs, sfs...)
+						if dfs == nil {
+							dfs = []int32{}
+						}
+						dst.setInt32Slice(dfs)
+					}
+				}
+			case isPointer: // E.g., *int32
+				mfi.merge = func(dst, src pointer) {
+					// NOTE: toInt32Ptr is not defined (see pointer_reflect.go).
+					/*
+						sfpp := src.toInt32Ptr()
+						if *sfpp != nil {
+							dfpp := dst.toInt32Ptr()
+							if *dfpp == nil {
+								*dfpp = Int32(**sfpp)
+							} else {
+								**dfpp = **sfpp
+							}
+						}
+					*/
+					sfp := src.getInt32Ptr()
+					if sfp != nil {
+						dfp := dst.getInt32Ptr()
+						if dfp == nil {
+							dst.setInt32Ptr(*sfp)
+						} else {
+							*dfp = *sfp
+						}
+					}
+				}
+			default: // E.g., int32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toInt32(); v != 0 {
+						*dst.toInt32() = v
+					}
+				}
+			}
+		case reflect.Int64:
+			switch {
+			case isSlice: // E.g., []int64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toInt64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toInt64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []int64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *int64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toInt64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toInt64Ptr()
+						if *dfpp == nil {
+							*dfpp = Int64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., int64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toInt64(); v != 0 {
+						*dst.toInt64() = v
+					}
+				}
+			}
+		case reflect.Uint32:
+			switch {
+			case isSlice: // E.g., []uint32
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toUint32Slice()
+					if *sfsp != nil {
+						dfsp := dst.toUint32Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []uint32{}
+						}
+					}
+				}
+			case isPointer: // E.g., *uint32
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toUint32Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toUint32Ptr()
+						if *dfpp == nil {
+							*dfpp = Uint32(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., uint32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toUint32(); v != 0 {
+						*dst.toUint32() = v
+					}
+				}
+			}
+		case reflect.Uint64:
+			switch {
+			case isSlice: // E.g., []uint64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toUint64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toUint64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []uint64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *uint64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toUint64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toUint64Ptr()
+						if *dfpp == nil {
+							*dfpp = Uint64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., uint64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toUint64(); v != 0 {
+						*dst.toUint64() = v
+					}
+				}
+			}
+		case reflect.Float32:
+			switch {
+			case isSlice: // E.g., []float32
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toFloat32Slice()
+					if *sfsp != nil {
+						dfsp := dst.toFloat32Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []float32{}
+						}
+					}
+				}
+			case isPointer: // E.g., *float32
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toFloat32Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toFloat32Ptr()
+						if *dfpp == nil {
+							*dfpp = Float32(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., float32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toFloat32(); v != 0 {
+						*dst.toFloat32() = v
+					}
+				}
+			}
+		case reflect.Float64:
+			switch {
+			case isSlice: // E.g., []float64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toFloat64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toFloat64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []float64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *float64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toFloat64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toFloat64Ptr()
+						if *dfpp == nil {
+							*dfpp = Float64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., float64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toFloat64(); v != 0 {
+						*dst.toFloat64() = v
+					}
+				}
+			}
+		case reflect.Bool:
+			switch {
+			case isSlice: // E.g., []bool
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toBoolSlice()
+					if *sfsp != nil {
+						dfsp := dst.toBoolSlice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []bool{}
+						}
+					}
+				}
+			case isPointer: // E.g., *bool
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toBoolPtr()
+					if *sfpp != nil {
+						dfpp := dst.toBoolPtr()
+						if *dfpp == nil {
+							*dfpp = Bool(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., bool
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toBool(); v {
+						*dst.toBool() = v
+					}
+				}
+			}
+		case reflect.String:
+			switch {
+			case isSlice: // E.g., []string
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toStringSlice()
+					if *sfsp != nil {
+						dfsp := dst.toStringSlice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []string{}
+						}
+					}
+				}
+			case isPointer: // E.g., *string
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toStringPtr()
+					if *sfpp != nil {
+						dfpp := dst.toStringPtr()
+						if *dfpp == nil {
+							*dfpp = String(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., string
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toString(); v != "" {
+						*dst.toString() = v
+					}
+				}
+			}
+		case reflect.Slice:
+			isProto3 := props.Prop[i].proto3
+			switch {
+			case isPointer:
+				panic("bad pointer in byte slice case in " + tf.Name())
+			case tf.Elem().Kind() != reflect.Uint8:
+				panic("bad element kind in byte slice case in " + tf.Name())
+			case isSlice: // E.g., [][]byte
+				mfi.merge = func(dst, src pointer) {
+					sbsp := src.toBytesSlice()
+					if *sbsp != nil {
+						dbsp := dst.toBytesSlice()
+						for _, sb := range *sbsp {
+							if sb == nil {
+								*dbsp = append(*dbsp, nil)
+							} else {
+								*dbsp = append(*dbsp, append([]byte{}, sb...))
+							}
+						}
+						if *dbsp == nil {
+							*dbsp = [][]byte{}
+						}
+					}
+				}
+			default: // E.g., []byte
+				mfi.merge = func(dst, src pointer) {
+					sbp := src.toBytes()
+					if *sbp != nil {
+						dbp := dst.toBytes()
+						if !isProto3 || len(*sbp) > 0 {
+							*dbp = append([]byte{}, *sbp...)
+						}
+					}
+				}
+			}
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("message field %s without pointer", tf))
+			case isSlice: // E.g., []*pb.T
+				mi := getMergeInfo(tf)
+				mfi.merge = func(dst, src pointer) {
+					sps := src.getPointerSlice()
+					if sps != nil {
+						dps := dst.getPointerSlice()
+						for _, sp := range sps {
+							var dp pointer
+							if !sp.isNil() {
+								dp = valToPointer(reflect.New(tf))
+								mi.merge(dp, sp)
+							}
+							dps = append(dps, dp)
+						}
+						if dps == nil {
+							dps = []pointer{}
+						}
+						dst.setPointerSlice(dps)
+					}
+				}
+			default: // E.g., *pb.T
+				mi := getMergeInfo(tf)
+				mfi.merge = func(dst, src pointer) {
+					sp := src.getPointer()
+					if !sp.isNil() {
+						dp := dst.getPointer()
+						if dp.isNil() {
+							dp = valToPointer(reflect.New(tf))
+							dst.setPointer(dp)
+						}
+						mi.merge(dp, sp)
+					}
+				}
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic("bad pointer or slice in map case in " + tf.Name())
+			default: // E.g., map[K]V
+				mfi.merge = func(dst, src pointer) {
+					sm := src.asPointerTo(tf).Elem()
+					if sm.Len() == 0 {
+						return
+					}
+					dm := dst.asPointerTo(tf).Elem()
+					if dm.IsNil() {
+						dm.Set(reflect.MakeMap(tf))
+					}
+
+					switch tf.Elem().Kind() {
+					case reflect.Ptr: // Proto struct (e.g., *T)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							val = reflect.ValueOf(Clone(val.Interface().(Message)))
+							dm.SetMapIndex(key, val)
+						}
+					case reflect.Slice: // E.g. Bytes type (e.g., []byte)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+							dm.SetMapIndex(key, val)
+						}
+					default: // Basic type (e.g., string)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							dm.SetMapIndex(key, val)
+						}
+					}
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic("bad pointer or slice in interface case in " + tf.Name())
+			default: // E.g., interface{}
+				// TODO: Make this faster?
+				mfi.merge = func(dst, src pointer) {
+					su := src.asPointerTo(tf).Elem()
+					if !su.IsNil() {
+						du := dst.asPointerTo(tf).Elem()
+						typ := su.Elem().Type()
+						if du.IsNil() || du.Elem().Type() != typ {
+							du.Set(reflect.New(typ.Elem())) // Initialize interface if empty
+						}
+						sv := su.Elem().Elem().Field(0)
+						if sv.Kind() == reflect.Ptr && sv.IsNil() {
+							return
+						}
+						dv := du.Elem().Elem().Field(0)
+						if dv.Kind() == reflect.Ptr && dv.IsNil() {
+							dv.Set(reflect.New(sv.Type().Elem())) // Initialize proto message if empty
+						}
+						switch sv.Type().Kind() {
+						case reflect.Ptr: // Proto struct (e.g., *T)
+							Merge(dv.Interface().(Message), sv.Interface().(Message))
+						case reflect.Slice: // E.g. Bytes type (e.g., []byte)
+							dv.Set(reflect.ValueOf(append([]byte{}, sv.Bytes()...)))
+						default: // Basic type (e.g., string)
+							dv.Set(sv)
+						}
+					}
+				}
+			}
+		default:
+			panic(fmt.Sprintf("merger not found for type:%s", tf))
+		}
+		mi.fields = append(mi.fields, mfi)
+	}
+
+	mi.unrecognized = invalidField
+	if f, ok := t.FieldByName("XXX_unrecognized"); ok {
+		if f.Type != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		mi.unrecognized = toField(&f)
+	}
+
+	atomic.StoreInt32(&mi.initialized, 1)
+}

vendor/github.com/golang/protobuf/proto/text.go

@@ -0,0 +1,843 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for writing the text protocol buffer format.
+
+import (
+	"bufio"
+	"bytes"
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"reflect"
+	"sort"
+	"strings"
+)
+
+var (
+	newline         = []byte("\n")
+	spaces          = []byte("                                        ")
+	endBraceNewline = []byte("}\n")
+	backslashN      = []byte{'\\', 'n'}
+	backslashR      = []byte{'\\', 'r'}
+	backslashT      = []byte{'\\', 't'}
+	backslashDQ     = []byte{'\\', '"'}
+	backslashBS     = []byte{'\\', '\\'}
+	posInf          = []byte("inf")
+	negInf          = []byte("-inf")
+	nan             = []byte("nan")
+)
+
+type writer interface {
+	io.Writer
+	WriteByte(byte) error
+}
+
+// textWriter is an io.Writer that tracks its indentation level.
+type textWriter struct {
+	ind      int
+	complete bool // if the current position is a complete line
+	compact  bool // whether to write out as a one-liner
+	w        writer
+}
+
+func (w *textWriter) WriteString(s string) (n int, err error) {
+	if !strings.Contains(s, "\n") {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		w.complete = false
+		return io.WriteString(w.w, s)
+	}
+	// WriteString is typically called without newlines, so this
+	// codepath and its copy are rare.  We copy to avoid
+	// duplicating all of Write's logic here.
+	return w.Write([]byte(s))
+}
+
+func (w *textWriter) Write(p []byte) (n int, err error) {
+	newlines := bytes.Count(p, newline)
+	if newlines == 0 {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		n, err = w.w.Write(p)
+		w.complete = false
+		return n, err
+	}
+
+	frags := bytes.SplitN(p, newline, newlines+1)
+	if w.compact {
+		for i, frag := range frags {
+			if i > 0 {
+				if err := w.w.WriteByte(' '); err != nil {
+					return n, err
+				}
+				n++
+			}
+			nn, err := w.w.Write(frag)
+			n += nn
+			if err != nil {
+				return n, err
+			}
+		}
+		return n, nil
+	}
+
+	for i, frag := range frags {
+		if w.complete {
+			w.writeIndent()
+		}
+		nn, err := w.w.Write(frag)
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		if i+1 < len(frags) {
+			if err := w.w.WriteByte('\n'); err != nil {
+				return n, err
+			}
+			n++
+		}
+	}
+	w.complete = len(frags[len(frags)-1]) == 0
+	return n, nil
+}
+
+func (w *textWriter) WriteByte(c byte) error {
+	if w.compact && c == '\n' {
+		c = ' '
+	}
+	if !w.compact && w.complete {
+		w.writeIndent()
+	}
+	err := w.w.WriteByte(c)
+	w.complete = c == '\n'
+	return err
+}
+
+func (w *textWriter) indent() { w.ind++ }
+
+func (w *textWriter) unindent() {
+	if w.ind == 0 {
+		log.Print("proto: textWriter unindented too far")
+		return
+	}
+	w.ind--
+}
+
+func writeName(w *textWriter, props *Properties) error {
+	if _, err := w.WriteString(props.OrigName); err != nil {
+		return err
+	}
+	if props.Wire != "group" {
+		return w.WriteByte(':')
+	}
+	return nil
+}
+
+func requiresQuotes(u string) bool {
+	// When type URL contains any characters except [0-9A-Za-z./\-]*, it must be quoted.
+	for _, ch := range u {
+		switch {
+		case ch == '.' || ch == '/' || ch == '_':
+			continue
+		case '0' <= ch && ch <= '9':
+			continue
+		case 'A' <= ch && ch <= 'Z':
+			continue
+		case 'a' <= ch && ch <= 'z':
+			continue
+		default:
+			return true
+		}
+	}
+	return false
+}
+
+// isAny reports whether sv is a google.protobuf.Any message
+func isAny(sv reflect.Value) bool {
+	type wkt interface {
+		XXX_WellKnownType() string
+	}
+	t, ok := sv.Addr().Interface().(wkt)
+	return ok && t.XXX_WellKnownType() == "Any"
+}
+
+// writeProto3Any writes an expanded google.protobuf.Any message.
+//
+// It returns (false, nil) if sv value can't be unmarshaled (e.g. because
+// required messages are not linked in).
+//
+// It returns (true, error) when sv was written in expanded format or an error
+// was encountered.
+func (tm *TextMarshaler) writeProto3Any(w *textWriter, sv reflect.Value) (bool, error) {
+	turl := sv.FieldByName("TypeUrl")
+	val := sv.FieldByName("Value")
+	if !turl.IsValid() || !val.IsValid() {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	b, ok := val.Interface().([]byte)
+	if !ok {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	parts := strings.Split(turl.String(), "/")
+	mt := MessageType(parts[len(parts)-1])
+	if mt == nil {
+		return false, nil
+	}
+	m := reflect.New(mt.Elem())
+	if err := Unmarshal(b, m.Interface().(Message)); err != nil {
+		return false, nil
+	}
+	w.Write([]byte("["))
+	u := turl.String()
+	if requiresQuotes(u) {
+		writeString(w, u)
+	} else {
+		w.Write([]byte(u))
+	}
+	if w.compact {
+		w.Write([]byte("]:<"))
+	} else {
+		w.Write([]byte("]: <\n"))
+		w.ind++
+	}
+	if err := tm.writeStruct(w, m.Elem()); err != nil {
+		return true, err
+	}
+	if w.compact {
+		w.Write([]byte("> "))
+	} else {
+		w.ind--
+		w.Write([]byte(">\n"))
+	}
+	return true, nil
+}
+
+func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
+	if tm.ExpandAny && isAny(sv) {
+		if canExpand, err := tm.writeProto3Any(w, sv); canExpand {
+			return err
+		}
+	}
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < sv.NumField(); i++ {
+		fv := sv.Field(i)
+		props := sprops.Prop[i]
+		name := st.Field(i).Name
+
+		if name == "XXX_NoUnkeyedLiteral" {
+			continue
+		}
+
+		if strings.HasPrefix(name, "XXX_") {
+			// There are two XXX_ fields:
+			//   XXX_unrecognized []byte
+			//   XXX_extensions   map[int32]proto.Extension
+			// The first is handled here;
+			// the second is handled at the bottom of this function.
+			if name == "XXX_unrecognized" && !fv.IsNil() {
+				if err := writeUnknownStruct(w, fv.Interface().([]byte)); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Ptr && fv.IsNil() {
+			// Field not filled in. This could be an optional field or
+			// a required field that wasn't filled in. Either way, there
+			// isn't anything we can show for it.
+			continue
+		}
+		if fv.Kind() == reflect.Slice && fv.IsNil() {
+			// Repeated field that is empty, or a bytes field that is unused.
+			continue
+		}
+
+		if props.Repeated && fv.Kind() == reflect.Slice {
+			// Repeated field.
+			for j := 0; j < fv.Len(); j++ {
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				v := fv.Index(j)
+				if v.Kind() == reflect.Ptr && v.IsNil() {
+					// A nil message in a repeated field is not valid,
+					// but we can handle that more gracefully than panicking.
+					if _, err := w.Write([]byte("<nil>\n")); err != nil {
+						return err
+					}
+					continue
+				}
+				if err := tm.writeAny(w, v, props); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Map {
+			// Map fields are rendered as a repeated struct with key/value fields.
+			keys := fv.MapKeys()
+			sort.Sort(mapKeys(keys))
+			for _, key := range keys {
+				val := fv.MapIndex(key)
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				// open struct
+				if err := w.WriteByte('<'); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				w.indent()
+				// key
+				if _, err := w.WriteString("key:"); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				if err := tm.writeAny(w, key, props.MapKeyProp); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+				// nil values aren't legal, but we can avoid panicking because of them.
+				if val.Kind() != reflect.Ptr || !val.IsNil() {
+					// value
+					if _, err := w.WriteString("value:"); err != nil {
+						return err
+					}
+					if !w.compact {
+						if err := w.WriteByte(' '); err != nil {
+							return err
+						}
+					}
+					if err := tm.writeAny(w, val, props.MapValProp); err != nil {
+						return err
+					}
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				// close struct
+				w.unindent()
+				if err := w.WriteByte('>'); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if props.proto3 && fv.Kind() == reflect.Slice && fv.Len() == 0 {
+			// empty bytes field
+			continue
+		}
+		if fv.Kind() != reflect.Ptr && fv.Kind() != reflect.Slice {
+			// proto3 non-repeated scalar field; skip if zero value
+			if isProto3Zero(fv) {
+				continue
+			}
+		}
+
+		if fv.Kind() == reflect.Interface {
+			// Check if it is a oneof.
+			if st.Field(i).Tag.Get("protobuf_oneof") != "" {
+				// fv is nil, or holds a pointer to generated struct.
+				// That generated struct has exactly one field,
+				// which has a protobuf struct tag.
+				if fv.IsNil() {
+					continue
+				}
+				inner := fv.Elem().Elem() // interface -> *T -> T
+				tag := inner.Type().Field(0).Tag.Get("protobuf")
+				props = new(Properties) // Overwrite the outer props var, but not its pointee.
+				props.Parse(tag)
+				// Write the value in the oneof, not the oneof itself.
+				fv = inner.Field(0)
+
+				// Special case to cope with malformed messages gracefully:
+				// If the value in the oneof is a nil pointer, don't panic
+				// in writeAny.
+				if fv.Kind() == reflect.Ptr && fv.IsNil() {
+					// Use errors.New so writeAny won't render quotes.
+					msg := errors.New("/* nil */")
+					fv = reflect.ValueOf(&msg).Elem()
+				}
+			}
+		}
+
+		if err := writeName(w, props); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+
+		// Enums have a String method, so writeAny will work fine.
+		if err := tm.writeAny(w, fv, props); err != nil {
+			return err
+		}
+
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+
+	// Extensions (the XXX_extensions field).
+	pv := sv.Addr()
+	if _, err := extendable(pv.Interface()); err == nil {
+		if err := tm.writeExtensions(w, pv); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// writeAny writes an arbitrary field.
+func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Properties) error {
+	v = reflect.Indirect(v)
+
+	// Floats have special cases.
+	if v.Kind() == reflect.Float32 || v.Kind() == reflect.Float64 {
+		x := v.Float()
+		var b []byte
+		switch {
+		case math.IsInf(x, 1):
+			b = posInf
+		case math.IsInf(x, -1):
+			b = negInf
+		case math.IsNaN(x):
+			b = nan
+		}
+		if b != nil {
+			_, err := w.Write(b)
+			return err
+		}
+		// Other values are handled below.
+	}
+
+	// We don't attempt to serialise every possible value type; only those
+	// that can occur in protocol buffers.
+	switch v.Kind() {
+	case reflect.Slice:
+		// Should only be a []byte; repeated fields are handled in writeStruct.
+		if err := writeString(w, string(v.Bytes())); err != nil {
+			return err
+		}
+	case reflect.String:
+		if err := writeString(w, v.String()); err != nil {
+			return err
+		}
+	case reflect.Struct:
+		// Required/optional group/message.
+		var bra, ket byte = '<', '>'
+		if props != nil && props.Wire == "group" {
+			bra, ket = '{', '}'
+		}
+		if err := w.WriteByte(bra); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte('\n'); err != nil {
+				return err
+			}
+		}
+		w.indent()
+		if v.CanAddr() {
+			// Calling v.Interface on a struct causes the reflect package to
+			// copy the entire struct. This is racy with the new Marshaler
+			// since we atomically update the XXX_sizecache.
+			//
+			// Thus, we retrieve a pointer to the struct if possible to avoid
+			// a race since v.Interface on the pointer doesn't copy the struct.
+			//
+			// If v is not addressable, then we are not worried about a race
+			// since it implies that the binary Marshaler cannot possibly be
+			// mutating this value.
+			v = v.Addr()
+		}
+		if etm, ok := v.Interface().(encoding.TextMarshaler); ok {
+			text, err := etm.MarshalText()
+			if err != nil {
+				return err
+			}
+			if _, err = w.Write(text); err != nil {
+				return err
+			}
+		} else {
+			if v.Kind() == reflect.Ptr {
+				v = v.Elem()
+			}
+			if err := tm.writeStruct(w, v); err != nil {
+				return err
+			}
+		}
+		w.unindent()
+		if err := w.WriteByte(ket); err != nil {
+			return err
+		}
+	default:
+		_, err := fmt.Fprint(w, v.Interface())
+		return err
+	}
+	return nil
+}
+
+// equivalent to C's isprint.
+func isprint(c byte) bool {
+	return c >= 0x20 && c < 0x7f
+}
+
+// writeString writes a string in the protocol buffer text format.
+// It is similar to strconv.Quote except we don't use Go escape sequences,
+// we treat the string as a byte sequence, and we use octal escapes.
+// These differences are to maintain interoperability with the other
+// languages' implementations of the text format.
+func writeString(w *textWriter, s string) error {
+	// use WriteByte here to get any needed indent
+	if err := w.WriteByte('"'); err != nil {
+		return err
+	}
+	// Loop over the bytes, not the runes.
+	for i := 0; i < len(s); i++ {
+		var err error
+		// Divergence from C++: we don't escape apostrophes.
+		// There's no need to escape them, and the C++ parser
+		// copes with a naked apostrophe.
+		switch c := s[i]; c {
+		case '\n':
+			_, err = w.w.Write(backslashN)
+		case '\r':
+			_, err = w.w.Write(backslashR)
+		case '\t':
+			_, err = w.w.Write(backslashT)
+		case '"':
+			_, err = w.w.Write(backslashDQ)
+		case '\\':
+			_, err = w.w.Write(backslashBS)
+		default:
+			if isprint(c) {
+				err = w.w.WriteByte(c)
+			} else {
+				_, err = fmt.Fprintf(w.w, "\\%03o", c)
+			}
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return w.WriteByte('"')
+}
+
+func writeUnknownStruct(w *textWriter, data []byte) (err error) {
+	if !w.compact {
+		if _, err := fmt.Fprintf(w, "/* %d unknown bytes */\n", len(data)); err != nil {
+			return err
+		}
+	}
+	b := NewBuffer(data)
+	for b.index < len(b.buf) {
+		x, err := b.DecodeVarint()
+		if err != nil {
+			_, err := fmt.Fprintf(w, "/* %v */\n", err)
+			return err
+		}
+		wire, tag := x&7, x>>3
+		if wire == WireEndGroup {
+			w.unindent()
+			if _, err := w.Write(endBraceNewline); err != nil {
+				return err
+			}
+			continue
+		}
+		if _, err := fmt.Fprint(w, tag); err != nil {
+			return err
+		}
+		if wire != WireStartGroup {
+			if err := w.WriteByte(':'); err != nil {
+				return err
+			}
+		}
+		if !w.compact || wire == WireStartGroup {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		switch wire {
+		case WireBytes:
+			buf, e := b.DecodeRawBytes(false)
+			if e == nil {
+				_, err = fmt.Fprintf(w, "%q", buf)
+			} else {
+				_, err = fmt.Fprintf(w, "/* %v */", e)
+			}
+		case WireFixed32:
+			x, err = b.DecodeFixed32()
+			err = writeUnknownInt(w, x, err)
+		case WireFixed64:
+			x, err = b.DecodeFixed64()
+			err = writeUnknownInt(w, x, err)
+		case WireStartGroup:
+			err = w.WriteByte('{')
+			w.indent()
+		case WireVarint:
+			x, err = b.DecodeVarint()
+			err = writeUnknownInt(w, x, err)
+		default:
+			_, err = fmt.Fprintf(w, "/* unknown wire type %d */", wire)
+		}
+		if err != nil {
+			return err
+		}
+		if err = w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeUnknownInt(w *textWriter, x uint64, err error) error {
+	if err == nil {
+		_, err = fmt.Fprint(w, x)
+	} else {
+		_, err = fmt.Fprintf(w, "/* %v */", err)
+	}
+	return err
+}
+
+type int32Slice []int32
+
+func (s int32Slice) Len() int           { return len(s) }
+func (s int32Slice) Less(i, j int) bool { return s[i] < s[j] }
+func (s int32Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// writeExtensions writes all the extensions in pv.
+// pv is assumed to be a pointer to a protocol message struct that is extendable.
+func (tm *TextMarshaler) writeExtensions(w *textWriter, pv reflect.Value) error {
+	emap := extensionMaps[pv.Type().Elem()]
+	ep, _ := extendable(pv.Interface())
+
+	// Order the extensions by ID.
+	// This isn't strictly necessary, but it will give us
+	// canonical output, which will also make testing easier.
+	m, mu := ep.extensionsRead()
+	if m == nil {
+		return nil
+	}
+	mu.Lock()
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids))
+	mu.Unlock()
+
+	for _, extNum := range ids {
+		ext := m[extNum]
+		var desc *ExtensionDesc
+		if emap != nil {
+			desc = emap[extNum]
+		}
+		if desc == nil {
+			// Unknown extension.
+			if err := writeUnknownStruct(w, ext.enc); err != nil {
+				return err
+			}
+			continue
+		}
+
+		pb, err := GetExtension(ep, desc)
+		if err != nil {
+			return fmt.Errorf("failed getting extension: %v", err)
+		}
+
+		// Repeated extensions will appear as a slice.
+		if !desc.repeated() {
+			if err := tm.writeExtension(w, desc.Name, pb); err != nil {
+				return err
+			}
+		} else {
+			v := reflect.ValueOf(pb)
+			for i := 0; i < v.Len(); i++ {
+				if err := tm.writeExtension(w, desc.Name, v.Index(i).Interface()); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (tm *TextMarshaler) writeExtension(w *textWriter, name string, pb interface{}) error {
+	if _, err := fmt.Fprintf(w, "[%s]:", name); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte(' '); err != nil {
+			return err
+		}
+	}
+	if err := tm.writeAny(w, reflect.ValueOf(pb), nil); err != nil {
+		return err
+	}
+	if err := w.WriteByte('\n'); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (w *textWriter) writeIndent() {
+	if !w.complete {
+		return
+	}
+	remain := w.ind * 2
+	for remain > 0 {
+		n := remain
+		if n > len(spaces) {
+			n = len(spaces)
+		}
+		w.w.Write(spaces[:n])
+		remain -= n
+	}
+	w.complete = false
+}
+
+// TextMarshaler is a configurable text format marshaler.
+type TextMarshaler struct {
+	Compact   bool // use compact text format (one line).
+	ExpandAny bool // expand google.protobuf.Any messages of known types
+}
+
+// Marshal writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func (tm *TextMarshaler) Marshal(w io.Writer, pb Message) error {
+	val := reflect.ValueOf(pb)
+	if pb == nil || val.IsNil() {
+		w.Write([]byte("<nil>"))
+		return nil
+	}
+	var bw *bufio.Writer
+	ww, ok := w.(writer)
+	if !ok {
+		bw = bufio.NewWriter(w)
+		ww = bw
+	}
+	aw := &textWriter{
+		w:        ww,
+		complete: true,
+		compact:  tm.Compact,
+	}
+
+	if etm, ok := pb.(encoding.TextMarshaler); ok {
+		text, err := etm.MarshalText()
+		if err != nil {
+			return err
+		}
+		if _, err = aw.Write(text); err != nil {
+			return err
+		}
+		if bw != nil {
+			return bw.Flush()
+		}
+		return nil
+	}
+	// Dereference the received pointer so we don't have outer < and >.
+	v := reflect.Indirect(val)
+	if err := tm.writeStruct(aw, v); err != nil {
+		return err
+	}
+	if bw != nil {
+		return bw.Flush()
+	}
+	return nil
+}
+
+// Text is the same as Marshal, but returns the string directly.
+func (tm *TextMarshaler) Text(pb Message) string {
+	var buf bytes.Buffer
+	tm.Marshal(&buf, pb)
+	return buf.String()
+}
+
+var (
+	defaultTextMarshaler = TextMarshaler{}
+	compactTextMarshaler = TextMarshaler{Compact: true}
+)
+
+// TODO: consider removing some of the Marshal functions below.
+
+// MarshalText writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func MarshalText(w io.Writer, pb Message) error { return defaultTextMarshaler.Marshal(w, pb) }
+
+// MarshalTextString is the same as MarshalText, but returns the string directly.
+func MarshalTextString(pb Message) string { return defaultTextMarshaler.Text(pb) }
+
+// CompactText writes a given protocol buffer in compact text format (one line).
+func CompactText(w io.Writer, pb Message) error { return compactTextMarshaler.Marshal(w, pb) }
+
+// CompactTextString is the same as CompactText, but returns the string directly.
+func CompactTextString(pb Message) string { return compactTextMarshaler.Text(pb) }

vendor/github.com/golang/protobuf/proto/text_parser.go

@@ -0,0 +1,880 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for parsing the Text protocol buffer format.
+// TODO: message sets.
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+// Error string emitted when deserializing Any and fields are already set
+const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
+
+type ParseError struct {
+	Message string
+	Line    int // 1-based line number
+	Offset  int // 0-based byte offset from start of input
+}
+
+func (p *ParseError) Error() string {
+	if p.Line == 1 {
+		// show offset only for first line
+		return fmt.Sprintf("line 1.%d: %v", p.Offset, p.Message)
+	}
+	return fmt.Sprintf("line %d: %v", p.Line, p.Message)
+}
+
+type token struct {
+	value    string
+	err      *ParseError
+	line     int    // line number
+	offset   int    // byte number from start of input, not start of line
+	unquoted string // the unquoted version of value, if it was a quoted string
+}
+
+func (t *token) String() string {
+	if t.err == nil {
+		return fmt.Sprintf("%q (line=%d, offset=%d)", t.value, t.line, t.offset)
+	}
+	return fmt.Sprintf("parse error: %v", t.err)
+}
+
+type textParser struct {
+	s            string // remaining input
+	done         bool   // whether the parsing is finished (success or error)
+	backed       bool   // whether back() was called
+	offset, line int
+	cur          token
+}
+
+func newTextParser(s string) *textParser {
+	p := new(textParser)
+	p.s = s
+	p.line = 1
+	p.cur.line = 1
+	return p
+}
+
+func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
+	pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
+	p.cur.err = pe
+	p.done = true
+	return pe
+}
+
+// Numbers and identifiers are matched by [-+._A-Za-z0-9]
+func isIdentOrNumberChar(c byte) bool {
+	switch {
+	case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
+		return true
+	case '0' <= c && c <= '9':
+		return true
+	}
+	switch c {
+	case '-', '+', '.', '_':
+		return true
+	}
+	return false
+}
+
+func isWhitespace(c byte) bool {
+	switch c {
+	case ' ', '\t', '\n', '\r':
+		return true
+	}
+	return false
+}
+
+func isQuote(c byte) bool {
+	switch c {
+	case '"', '\'':
+		return true
+	}
+	return false
+}
+
+func (p *textParser) skipWhitespace() {
+	i := 0
+	for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
+		if p.s[i] == '#' {
+			// comment; skip to end of line or input
+			for i < len(p.s) && p.s[i] != '\n' {
+				i++
+			}
+			if i == len(p.s) {
+				break
+			}
+		}
+		if p.s[i] == '\n' {
+			p.line++
+		}
+		i++
+	}
+	p.offset += i
+	p.s = p.s[i:len(p.s)]
+	if len(p.s) == 0 {
+		p.done = true
+	}
+}
+
+func (p *textParser) advance() {
+	// Skip whitespace
+	p.skipWhitespace()
+	if p.done {
+		return
+	}
+
+	// Start of non-whitespace
+	p.cur.err = nil
+	p.cur.offset, p.cur.line = p.offset, p.line
+	p.cur.unquoted = ""
+	switch p.s[0] {
+	case '<', '>', '{', '}', ':', '[', ']', ';', ',', '/':
+		// Single symbol
+		p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
+	case '"', '\'':
+		// Quoted string
+		i := 1
+		for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
+			if p.s[i] == '\\' && i+1 < len(p.s) {
+				// skip escaped char
+				i++
+			}
+			i++
+		}
+		if i >= len(p.s) || p.s[i] != p.s[0] {
+			p.errorf("unmatched quote")
+			return
+		}
+		unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
+		if err != nil {
+			p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
+			return
+		}
+		p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
+		p.cur.unquoted = unq
+	default:
+		i := 0
+		for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
+			i++
+		}
+		if i == 0 {
+			p.errorf("unexpected byte %#x", p.s[0])
+			return
+		}
+		p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
+	}
+	p.offset += len(p.cur.value)
+}
+
+var (
+	errBadUTF8 = errors.New("proto: bad UTF-8")
+)
+
+func unquoteC(s string, quote rune) (string, error) {
+	// This is based on C++'s tokenizer.cc.
+	// Despite its name, this is *not* parsing C syntax.
+	// For instance, "\0" is an invalid quoted string.
+
+	// Avoid allocation in trivial cases.
+	simple := true
+	for _, r := range s {
+		if r == '\\' || r == quote {
+			simple = false
+			break
+		}
+	}
+	if simple {
+		return s, nil
+	}
+
+	buf := make([]byte, 0, 3*len(s)/2)
+	for len(s) > 0 {
+		r, n := utf8.DecodeRuneInString(s)
+		if r == utf8.RuneError && n == 1 {
+			return "", errBadUTF8
+		}
+		s = s[n:]
+		if r != '\\' {
+			if r < utf8.RuneSelf {
+				buf = append(buf, byte(r))
+			} else {
+				buf = append(buf, string(r)...)
+			}
+			continue
+		}
+
+		ch, tail, err := unescape(s)
+		if err != nil {
+			return "", err
+		}
+		buf = append(buf, ch...)
+		s = tail
+	}
+	return string(buf), nil
+}
+
+func unescape(s string) (ch string, tail string, err error) {
+	r, n := utf8.DecodeRuneInString(s)
+	if r == utf8.RuneError && n == 1 {
+		return "", "", errBadUTF8
+	}
+	s = s[n:]
+	switch r {
+	case 'a':
+		return "\a", s, nil
+	case 'b':
+		return "\b", s, nil
+	case 'f':
+		return "\f", s, nil
+	case 'n':
+		return "\n", s, nil
+	case 'r':
+		return "\r", s, nil
+	case 't':
+		return "\t", s, nil
+	case 'v':
+		return "\v", s, nil
+	case '?':
+		return "?", s, nil // trigraph workaround
+	case '\'', '"', '\\':
+		return string(r), s, nil
+	case '0', '1', '2', '3', '4', '5', '6', '7':
+		if len(s) < 2 {
+			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
+		}
+		ss := string(r) + s[:2]
+		s = s[2:]
+		i, err := strconv.ParseUint(ss, 8, 8)
+		if err != nil {
+			return "", "", fmt.Errorf(`\%s contains non-octal digits`, ss)
+		}
+		return string([]byte{byte(i)}), s, nil
+	case 'x', 'X', 'u', 'U':
+		var n int
+		switch r {
+		case 'x', 'X':
+			n = 2
+		case 'u':
+			n = 4
+		case 'U':
+			n = 8
+		}
+		if len(s) < n {
+			return "", "", fmt.Errorf(`\%c requires %d following digits`, r, n)
+		}
+		ss := s[:n]
+		s = s[n:]
+		i, err := strconv.ParseUint(ss, 16, 64)
+		if err != nil {
+			return "", "", fmt.Errorf(`\%c%s contains non-hexadecimal digits`, r, ss)
+		}
+		if r == 'x' || r == 'X' {
+			return string([]byte{byte(i)}), s, nil
+		}
+		if i > utf8.MaxRune {
+			return "", "", fmt.Errorf(`\%c%s is not a valid Unicode code point`, r, ss)
+		}
+		return string(i), s, nil
+	}
+	return "", "", fmt.Errorf(`unknown escape \%c`, r)
+}
+
+// Back off the parser by one token. Can only be done between calls to next().
+// It makes the next advance() a no-op.
+func (p *textParser) back() { p.backed = true }
+
+// Advances the parser and returns the new current token.
+func (p *textParser) next() *token {
+	if p.backed || p.done {
+		p.backed = false
+		return &p.cur
+	}
+	p.advance()
+	if p.done {
+		p.cur.value = ""
+	} else if len(p.cur.value) > 0 && isQuote(p.cur.value[0]) {
+		// Look for multiple quoted strings separated by whitespace,
+		// and concatenate them.
+		cat := p.cur
+		for {
+			p.skipWhitespace()
+			if p.done || !isQuote(p.s[0]) {
+				break
+			}
+			p.advance()
+			if p.cur.err != nil {
+				return &p.cur
+			}
+			cat.value += " " + p.cur.value
+			cat.unquoted += p.cur.unquoted
+		}
+		p.done = false // parser may have seen EOF, but we want to return cat
+		p.cur = cat
+	}
+	return &p.cur
+}
+
+func (p *textParser) consumeToken(s string) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != s {
+		p.back()
+		return p.errorf("expected %q, found %q", s, tok.value)
+	}
+	return nil
+}
+
+// Return a RequiredNotSetError indicating which required field was not set.
+func (p *textParser) missingRequiredFieldError(sv reflect.Value) *RequiredNotSetError {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < st.NumField(); i++ {
+		if !isNil(sv.Field(i)) {
+			continue
+		}
+
+		props := sprops.Prop[i]
+		if props.Required {
+			return &RequiredNotSetError{fmt.Sprintf("%v.%v", st, props.OrigName)}
+		}
+	}
+	return &RequiredNotSetError{fmt.Sprintf("%v.<unknown field name>", st)} // should not happen
+}
+
+// Returns the index in the struct for the named field, as well as the parsed tag properties.
+func structFieldByName(sprops *StructProperties, name string) (int, *Properties, bool) {
+	i, ok := sprops.decoderOrigNames[name]
+	if ok {
+		return i, sprops.Prop[i], true
+	}
+	return -1, nil, false
+}
+
+// Consume a ':' from the input stream (if the next token is a colon),
+// returning an error if a colon is needed but not present.
+func (p *textParser) checkForColon(props *Properties, typ reflect.Type) *ParseError {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ":" {
+		// Colon is optional when the field is a group or message.
+		needColon := true
+		switch props.Wire {
+		case "group":
+			needColon = false
+		case "bytes":
+			// A "bytes" field is either a message, a string, or a repeated field;
+			// those three become *T, *string and []T respectively, so we can check for
+			// this field being a pointer to a non-string.
+			if typ.Kind() == reflect.Ptr {
+				// *T or *string
+				if typ.Elem().Kind() == reflect.String {
+					break
+				}
+			} else if typ.Kind() == reflect.Slice {
+				// []T or []*T
+				if typ.Elem().Kind() != reflect.Ptr {
+					break
+				}
+			} else if typ.Kind() == reflect.String {
+				// The proto3 exception is for a string field,
+				// which requires a colon.
+				break
+			}
+			needColon = false
+		}
+		if needColon {
+			return p.errorf("expected ':', found %q", tok.value)
+		}
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	reqCount := sprops.reqCount
+	var reqFieldErr error
+	fieldSet := make(map[string]bool)
+	// A struct is a sequence of "name: value", terminated by one of
+	// '>' or '}', or the end of the input.  A name may also be
+	// "[extension]" or "[type/url]".
+	//
+	// The whole struct can also be an expanded Any message, like:
+	// [type/url] < ... struct contents ... >
+	for {
+		tok := p.next()
+		if tok.err != nil {
+			return tok.err
+		}
+		if tok.value == terminator {
+			break
+		}
+		if tok.value == "[" {
+			// Looks like an extension or an Any.
+			//
+			// TODO: Check whether we need to handle
+			// namespace rooted names (e.g. ".something.Foo").
+			extName, err := p.consumeExtName()
+			if err != nil {
+				return err
+			}
+
+			if s := strings.LastIndex(extName, "/"); s >= 0 {
+				// If it contains a slash, it's an Any type URL.
+				messageName := extName[s+1:]
+				mt := MessageType(messageName)
+				if mt == nil {
+					return p.errorf("unrecognized message %q in google.protobuf.Any", messageName)
+				}
+				tok = p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				// consume an optional colon
+				if tok.value == ":" {
+					tok = p.next()
+					if tok.err != nil {
+						return tok.err
+					}
+				}
+				var terminator string
+				switch tok.value {
+				case "<":
+					terminator = ">"
+				case "{":
+					terminator = "}"
+				default:
+					return p.errorf("expected '{' or '<', found %q", tok.value)
+				}
+				v := reflect.New(mt.Elem())
+				if pe := p.readStruct(v.Elem(), terminator); pe != nil {
+					return pe
+				}
+				b, err := Marshal(v.Interface().(Message))
+				if err != nil {
+					return p.errorf("failed to marshal message of type %q: %v", messageName, err)
+				}
+				if fieldSet["type_url"] {
+					return p.errorf(anyRepeatedlyUnpacked, "type_url")
+				}
+				if fieldSet["value"] {
+					return p.errorf(anyRepeatedlyUnpacked, "value")
+				}
+				sv.FieldByName("TypeUrl").SetString(extName)
+				sv.FieldByName("Value").SetBytes(b)
+				fieldSet["type_url"] = true
+				fieldSet["value"] = true
+				continue
+			}
+
+			var desc *ExtensionDesc
+			// This could be faster, but it's functional.
+			// TODO: Do something smarter than a linear scan.
+			for _, d := range RegisteredExtensions(reflect.New(st).Interface().(Message)) {
+				if d.Name == extName {
+					desc = d
+					break
+				}
+			}
+			if desc == nil {
+				return p.errorf("unrecognized extension %q", extName)
+			}
+
+			props := &Properties{}
+			props.Parse(desc.Tag)
+
+			typ := reflect.TypeOf(desc.ExtensionType)
+			if err := p.checkForColon(props, typ); err != nil {
+				return err
+			}
+
+			rep := desc.repeated()
+
+			// Read the extension structure, and set it in
+			// the value we're constructing.
+			var ext reflect.Value
+			if !rep {
+				ext = reflect.New(typ).Elem()
+			} else {
+				ext = reflect.New(typ.Elem()).Elem()
+			}
+			if err := p.readAny(ext, props); err != nil {
+				if _, ok := err.(*RequiredNotSetError); !ok {
+					return err
+				}
+				reqFieldErr = err
+			}
+			ep := sv.Addr().Interface().(Message)
+			if !rep {
+				SetExtension(ep, desc, ext.Interface())
+			} else {
+				old, err := GetExtension(ep, desc)
+				var sl reflect.Value
+				if err == nil {
+					sl = reflect.ValueOf(old) // existing slice
+				} else {
+					sl = reflect.MakeSlice(typ, 0, 1)
+				}
+				sl = reflect.Append(sl, ext)
+				SetExtension(ep, desc, sl.Interface())
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// This is a normal, non-extension field.
+		name := tok.value
+		var dst reflect.Value
+		fi, props, ok := structFieldByName(sprops, name)
+		if ok {
+			dst = sv.Field(fi)
+		} else if oop, ok := sprops.OneofTypes[name]; ok {
+			// It is a oneof.
+			props = oop.Prop
+			nv := reflect.New(oop.Type.Elem())
+			dst = nv.Elem().Field(0)
+			field := sv.Field(oop.Field)
+			if !field.IsNil() {
+				return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
+			}
+			field.Set(nv)
+		}
+		if !dst.IsValid() {
+			return p.errorf("unknown field name %q in %v", name, st)
+		}
+
+		if dst.Kind() == reflect.Map {
+			// Consume any colon.
+			if err := p.checkForColon(props, dst.Type()); err != nil {
+				return err
+			}
+
+			// Construct the map if it doesn't already exist.
+			if dst.IsNil() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			}
+			key := reflect.New(dst.Type().Key()).Elem()
+			val := reflect.New(dst.Type().Elem()).Elem()
+
+			// The map entry should be this sequence of tokens:
+			//	< key : KEY value : VALUE >
+			// However, implementations may omit key or value, and technically
+			// we should support them in any order.  See b/28924776 for a time
+			// this went wrong.
+
+			tok := p.next()
+			var terminator string
+			switch tok.value {
+			case "<":
+				terminator = ">"
+			case "{":
+				terminator = "}"
+			default:
+				return p.errorf("expected '{' or '<', found %q", tok.value)
+			}
+			for {
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == terminator {
+					break
+				}
+				switch tok.value {
+				case "key":
+					if err := p.consumeToken(":"); err != nil {
+						return err
+					}
+					if err := p.readAny(key, props.MapKeyProp); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				case "value":
+					if err := p.checkForColon(props.MapValProp, dst.Type().Elem()); err != nil {
+						return err
+					}
+					if err := p.readAny(val, props.MapValProp); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				default:
+					p.back()
+					return p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
+				}
+			}
+
+			dst.SetMapIndex(key, val)
+			continue
+		}
+
+		// Check that it's not already set if it's not a repeated field.
+		if !props.Repeated && fieldSet[name] {
+			return p.errorf("non-repeated field %q was repeated", name)
+		}
+
+		if err := p.checkForColon(props, dst.Type()); err != nil {
+			return err
+		}
+
+		// Parse into the field.
+		fieldSet[name] = true
+		if err := p.readAny(dst, props); err != nil {
+			if _, ok := err.(*RequiredNotSetError); !ok {
+				return err
+			}
+			reqFieldErr = err
+		}
+		if props.Required {
+			reqCount--
+		}
+
+		if err := p.consumeOptionalSeparator(); err != nil {
+			return err
+		}
+
+	}
+
+	if reqCount > 0 {
+		return p.missingRequiredFieldError(sv)
+	}
+	return reqFieldErr
+}
+
+// consumeExtName consumes extension name or expanded Any type URL and the
+// following ']'. It returns the name or URL consumed.
+func (p *textParser) consumeExtName() (string, error) {
+	tok := p.next()
+	if tok.err != nil {
+		return "", tok.err
+	}
+
+	// If extension name or type url is quoted, it's a single token.
+	if len(tok.value) > 2 && isQuote(tok.value[0]) && tok.value[len(tok.value)-1] == tok.value[0] {
+		name, err := unquoteC(tok.value[1:len(tok.value)-1], rune(tok.value[0]))
+		if err != nil {
+			return "", err
+		}
+		return name, p.consumeToken("]")
+	}
+
+	// Consume everything up to "]"
+	var parts []string
+	for tok.value != "]" {
+		parts = append(parts, tok.value)
+		tok = p.next()
+		if tok.err != nil {
+			return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
+		}
+		if p.done && tok.value != "]" {
+			return "", p.errorf("unclosed type_url or extension name")
+		}
+	}
+	return strings.Join(parts, ""), nil
+}
+
+// consumeOptionalSeparator consumes an optional semicolon or comma.
+// It is used in readStruct to provide backward compatibility.
+func (p *textParser) consumeOptionalSeparator() error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ";" && tok.value != "," {
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readAny(v reflect.Value, props *Properties) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value == "" {
+		return p.errorf("unexpected EOF")
+	}
+
+	switch fv := v; fv.Kind() {
+	case reflect.Slice:
+		at := v.Type()
+		if at.Elem().Kind() == reflect.Uint8 {
+			// Special case for []byte
+			if tok.value[0] != '"' && tok.value[0] != '\'' {
+				// Deliberately written out here, as the error after
+				// this switch statement would write "invalid []byte: ...",
+				// which is not as user-friendly.
+				return p.errorf("invalid string: %v", tok.value)
+			}
+			bytes := []byte(tok.unquoted)
+			fv.Set(reflect.ValueOf(bytes))
+			return nil
+		}
+		// Repeated field.
+		if tok.value == "[" {
+			// Repeated field with list notation, like [1,2,3].
+			for {
+				fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+				err := p.readAny(fv.Index(fv.Len()-1), props)
+				if err != nil {
+					return err
+				}
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == "]" {
+					break
+				}
+				if tok.value != "," {
+					return p.errorf("Expected ']' or ',' found %q", tok.value)
+				}
+			}
+			return nil
+		}
+		// One value of the repeated field.
+		p.back()
+		fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+		return p.readAny(fv.Index(fv.Len()-1), props)
+	case reflect.Bool:
+		// true/1/t/True or false/f/0/False.
+		switch tok.value {
+		case "true", "1", "t", "True":
+			fv.SetBool(true)
+			return nil
+		case "false", "0", "f", "False":
+			fv.SetBool(false)
+			return nil
+		}
+	case reflect.Float32, reflect.Float64:
+		v := tok.value
+		// Ignore 'f' for compatibility with output generated by C++, but don't
+		// remove 'f' when the value is "-inf" or "inf".
+		if strings.HasSuffix(v, "f") && tok.value != "-inf" && tok.value != "inf" {
+			v = v[:len(v)-1]
+		}
+		if f, err := strconv.ParseFloat(v, fv.Type().Bits()); err == nil {
+			fv.SetFloat(f)
+			return nil
+		}
+	case reflect.Int32:
+		if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+		if len(props.Enum) == 0 {
+			break
+		}
+		m, ok := enumValueMaps[props.Enum]
+		if !ok {
+			break
+		}
+		x, ok := m[tok.value]
+		if !ok {
+			break
+		}
+		fv.SetInt(int64(x))
+		return nil
+	case reflect.Int64:
+		if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+	case reflect.Ptr:
+		// A basic field (indirected through pointer), or a repeated message/group
+		p.back()
+		fv.Set(reflect.New(fv.Type().Elem()))
+		return p.readAny(fv.Elem(), props)
+	case reflect.String:
+		if tok.value[0] == '"' || tok.value[0] == '\'' {
+			fv.SetString(tok.unquoted)
+			return nil
+		}
+	case reflect.Struct:
+		var terminator string
+		switch tok.value {
+		case "{":
+			terminator = "}"
+		case "<":
+			terminator = ">"
+		default:
+			return p.errorf("expected '{' or '<', found %q", tok.value)
+		}
+		// TODO: Handle nested messages which implement encoding.TextUnmarshaler.
+		return p.readStruct(fv, terminator)
+	case reflect.Uint32:
+		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+			fv.SetUint(uint64(x))
+			return nil
+		}
+	case reflect.Uint64:
+		if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+			fv.SetUint(x)
+			return nil
+		}
+	}
+	return p.errorf("invalid %v: %v", v.Type(), tok.value)
+}
+
+// UnmarshalText reads a protocol buffer in Text format. UnmarshalText resets pb
+// before starting to unmarshal, so any existing data in pb is always removed.
+// If a required field is not set and no other error occurs,
+// UnmarshalText returns *RequiredNotSetError.
+func UnmarshalText(s string, pb Message) error {
+	if um, ok := pb.(encoding.TextUnmarshaler); ok {
+		return um.UnmarshalText([]byte(s))
+	}
+	pb.Reset()
+	v := reflect.ValueOf(pb)
+	return newTextParser(s).readStruct(v.Elem(), "")
+}

vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
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+
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+      identification within third-party archives.
+
+   Copyright {yyyy} {name of copyright owner}
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/matttproud/golang_protobuf_extensions/NOTICE

@@ -0,0 +1 @@
+Copyright 2012 Matt T. Proud (matt.proud@gmail.com)

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/.gitignore

@@ -0,0 +1 @@
+cover.dat

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/Makefile

@@ -0,0 +1,7 @@
+all:
+
+cover:
+	go test -cover -v -coverprofile=cover.dat ./...
+	go tool cover -func cover.dat
+
+.PHONY: cover

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go

@@ -0,0 +1,75 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+var errInvalidVarint = errors.New("invalid varint32 encountered")
+
+// ReadDelimited decodes a message from the provided length-delimited stream,
+// where the length is encoded as 32-bit varint prefix to the message body.
+// It returns the total number of bytes read and any applicable error.  This is
+// roughly equivalent to the companion Java API's
+// MessageLite#parseDelimitedFrom.  As per the reader contract, this function
+// calls r.Read repeatedly as required until exactly one message including its
+// prefix is read and decoded (or an error has occurred).  The function never
+// reads more bytes from the stream than required.  The function never returns
+// an error if a message has been read and decoded correctly, even if the end
+// of the stream has been reached in doing so.  In that case, any subsequent
+// calls return (0, io.EOF).
+func ReadDelimited(r io.Reader, m proto.Message) (n int, err error) {
+	// Per AbstractParser#parsePartialDelimitedFrom with
+	// CodedInputStream#readRawVarint32.
+	var headerBuf [binary.MaxVarintLen32]byte
+	var bytesRead, varIntBytes int
+	var messageLength uint64
+	for varIntBytes == 0 { // i.e. no varint has been decoded yet.
+		if bytesRead >= len(headerBuf) {
+			return bytesRead, errInvalidVarint
+		}
+		// We have to read byte by byte here to avoid reading more bytes
+		// than required. Each read byte is appended to what we have
+		// read before.
+		newBytesRead, err := r.Read(headerBuf[bytesRead : bytesRead+1])
+		if newBytesRead == 0 {
+			if err != nil {
+				return bytesRead, err
+			}
+			// A Reader should not return (0, nil), but if it does,
+			// it should be treated as no-op (according to the
+			// Reader contract). So let's go on...
+			continue
+		}
+		bytesRead += newBytesRead
+		// Now present everything read so far to the varint decoder and
+		// see if a varint can be decoded already.
+		messageLength, varIntBytes = proto.DecodeVarint(headerBuf[:bytesRead])
+	}
+
+	messageBuf := make([]byte, messageLength)
+	newBytesRead, err := io.ReadFull(r, messageBuf)
+	bytesRead += newBytesRead
+	if err != nil {
+		return bytesRead, err
+	}
+
+	return bytesRead, proto.Unmarshal(messageBuf, m)
+}

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go

@@ -0,0 +1,16 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package pbutil provides record length-delimited Protocol Buffer streaming.
+package pbutil

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go

@@ -0,0 +1,46 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// WriteDelimited encodes and dumps a message to the provided writer prefixed
+// with a 32-bit varint indicating the length of the encoded message, producing
+// a length-delimited record stream, which can be used to chain together
+// encoded messages of the same type together in a file.  It returns the total
+// number of bytes written and any applicable error.  This is roughly
+// equivalent to the companion Java API's MessageLite#writeDelimitedTo.
+func WriteDelimited(w io.Writer, m proto.Message) (n int, err error) {
+	buffer, err := proto.Marshal(m)
+	if err != nil {
+		return 0, err
+	}
+
+	var buf [binary.MaxVarintLen32]byte
+	encodedLength := binary.PutUvarint(buf[:], uint64(len(buffer)))
+
+	sync, err := w.Write(buf[:encodedLength])
+	if err != nil {
+		return sync, err
+	}
+
+	n, err = w.Write(buffer)
+	return n + sync, err
+}

vendor/github.com/prometheus/client_golang/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/client_golang/NOTICE

@@ -0,0 +1,23 @@
+Prometheus instrumentation library for Go applications
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
+
+
+The following components are included in this product:
+
+perks - a fork of https://github.com/bmizerany/perks
+https://github.com/beorn7/perks
+Copyright 2013-2015 Blake Mizerany, Björn Rabenstein
+See https://github.com/beorn7/perks/blob/master/README.md for license details.
+
+Go support for Protocol Buffers - Google's data interchange format
+http://github.com/golang/protobuf/
+Copyright 2010 The Go Authors
+See source code for license details.
+
+Support for streaming Protocol Buffer messages for the Go language (golang).
+https://github.com/matttproud/golang_protobuf_extensions
+Copyright 2013 Matt T. Proud
+Licensed under the Apache License, Version 2.0

vendor/github.com/prometheus/client_golang/prometheus/.gitignore

@@ -0,0 +1 @@
+command-line-arguments.test

vendor/github.com/prometheus/client_golang/prometheus/README.md

@@ -0,0 +1 @@
+See [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus).

vendor/github.com/prometheus/client_golang/prometheus/collector.go

@@ -0,0 +1,120 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Collector is the interface implemented by anything that can be used by
+// Prometheus to collect metrics. A Collector has to be registered for
+// collection. See Registerer.Register.
+//
+// The stock metrics provided by this package (Gauge, Counter, Summary,
+// Histogram, Untyped) are also Collectors (which only ever collect one metric,
+// namely itself). An implementer of Collector may, however, collect multiple
+// metrics in a coordinated fashion and/or create metrics on the fly. Examples
+// for collectors already implemented in this library are the metric vectors
+// (i.e. collection of multiple instances of the same Metric but with different
+// label values) like GaugeVec or SummaryVec, and the ExpvarCollector.
+type Collector interface {
+	// Describe sends the super-set of all possible descriptors of metrics
+	// collected by this Collector to the provided channel and returns once
+	// the last descriptor has been sent. The sent descriptors fulfill the
+	// consistency and uniqueness requirements described in the Desc
+	// documentation.
+	//
+	// It is valid if one and the same Collector sends duplicate
+	// descriptors. Those duplicates are simply ignored. However, two
+	// different Collectors must not send duplicate descriptors.
+	//
+	// Sending no descriptor at all marks the Collector as “unchecked”,
+	// i.e. no checks will be performed at registration time, and the
+	// Collector may yield any Metric it sees fit in its Collect method.
+	//
+	// This method idempotently sends the same descriptors throughout the
+	// lifetime of the Collector. It may be called concurrently and
+	// therefore must be implemented in a concurrency safe way.
+	//
+	// If a Collector encounters an error while executing this method, it
+	// must send an invalid descriptor (created with NewInvalidDesc) to
+	// signal the error to the registry.
+	Describe(chan<- *Desc)
+	// Collect is called by the Prometheus registry when collecting
+	// metrics. The implementation sends each collected metric via the
+	// provided channel and returns once the last metric has been sent. The
+	// descriptor of each sent metric is one of those returned by Describe
+	// (unless the Collector is unchecked, see above). Returned metrics that
+	// share the same descriptor must differ in their variable label
+	// values.
+	//
+	// This method may be called concurrently and must therefore be
+	// implemented in a concurrency safe way. Blocking occurs at the expense
+	// of total performance of rendering all registered metrics. Ideally,
+	// Collector implementations support concurrent readers.
+	Collect(chan<- Metric)
+}
+
+// DescribeByCollect is a helper to implement the Describe method of a custom
+// Collector. It collects the metrics from the provided Collector and sends
+// their descriptors to the provided channel.
+//
+// If a Collector collects the same metrics throughout its lifetime, its
+// Describe method can simply be implemented as:
+//
+//   func (c customCollector) Describe(ch chan<- *Desc) {
+//   	DescribeByCollect(c, ch)
+//   }
+//
+// However, this will not work if the metrics collected change dynamically over
+// the lifetime of the Collector in a way that their combined set of descriptors
+// changes as well. The shortcut implementation will then violate the contract
+// of the Describe method. If a Collector sometimes collects no metrics at all
+// (for example vectors like CounterVec, GaugeVec, etc., which only collect
+// metrics after a metric with a fully specified label set has been accessed),
+// it might even get registered as an unchecked Collecter (cf. the Register
+// method of the Registerer interface). Hence, only use this shortcut
+// implementation of Describe if you are certain to fulfill the contract.
+//
+// The Collector example demonstrates a use of DescribeByCollect.
+func DescribeByCollect(c Collector, descs chan<- *Desc) {
+	metrics := make(chan Metric)
+	go func() {
+		c.Collect(metrics)
+		close(metrics)
+	}()
+	for m := range metrics {
+		descs <- m.Desc()
+	}
+}
+
+// selfCollector implements Collector for a single Metric so that the Metric
+// collects itself. Add it as an anonymous field to a struct that implements
+// Metric, and call init with the Metric itself as an argument.
+type selfCollector struct {
+	self Metric
+}
+
+// init provides the selfCollector with a reference to the metric it is supposed
+// to collect. It is usually called within the factory function to create a
+// metric. See example.
+func (c *selfCollector) init(self Metric) {
+	c.self = self
+}
+
+// Describe implements Collector.
+func (c *selfCollector) Describe(ch chan<- *Desc) {
+	ch <- c.self.Desc()
+}
+
+// Collect implements Collector.
+func (c *selfCollector) Collect(ch chan<- Metric) {
+	ch <- c.self
+}

vendor/github.com/prometheus/client_golang/prometheus/counter.go

@@ -0,0 +1,277 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"math"
+	"sync/atomic"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Counter is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+//
+// A Counter is typically used to count requests served, tasks completed, errors
+// occurred, etc.
+//
+// To create Counter instances, use NewCounter.
+type Counter interface {
+	Metric
+	Collector
+
+	// Inc increments the counter by 1. Use Add to increment it by arbitrary
+	// non-negative values.
+	Inc()
+	// Add adds the given value to the counter. It panics if the value is <
+	// 0.
+	Add(float64)
+}
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts Opts
+
+// NewCounter creates a new Counter based on the provided CounterOpts.
+//
+// The returned implementation tracks the counter value in two separate
+// variables, a float64 and a uint64. The latter is used to track calls of the
+// Inc method and calls of the Add method with a value that can be represented
+// as a uint64. This allows atomic increments of the counter with optimal
+// performance. (It is common to have an Inc call in very hot execution paths.)
+// Both internal tracking values are added up in the Write method. This has to
+// be taken into account when it comes to precision and overflow behavior.
+func NewCounter(opts CounterOpts) Counter {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	)
+	result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
+	result.init(result) // Init self-collection.
+	return result
+}
+
+type counter struct {
+	// valBits contains the bits of the represented float64 value, while
+	// valInt stores values that are exact integers. Both have to go first
+	// in the struct to guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+	valInt  uint64
+
+	selfCollector
+	desc *Desc
+
+	labelPairs []*dto.LabelPair
+}
+
+func (c *counter) Desc() *Desc {
+	return c.desc
+}
+
+func (c *counter) Add(v float64) {
+	if v < 0 {
+		panic(errors.New("counter cannot decrease in value"))
+	}
+	ival := uint64(v)
+	if float64(ival) == v {
+		atomic.AddUint64(&c.valInt, ival)
+		return
+	}
+
+	for {
+		oldBits := atomic.LoadUint64(&c.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (c *counter) Inc() {
+	atomic.AddUint64(&c.valInt, 1)
+}
+
+func (c *counter) Write(out *dto.Metric) error {
+	fval := math.Float64frombits(atomic.LoadUint64(&c.valBits))
+	ival := atomic.LoadUint64(&c.valInt)
+	val := fval + float64(ival)
+
+	return populateMetric(CounterValue, val, c.labelPairs, out)
+}
+
+// CounterVec is a Collector that bundles a set of Counters that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. number of HTTP requests, partitioned by response code and
+// method). Create instances with NewCounterVec.
+type CounterVec struct {
+	*metricVec
+}
+
+// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
+// partitioned by the given label names.
+func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &CounterVec{
+		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			if len(lvs) != len(desc.variableLabels) {
+				panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs))
+			}
+			result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+			result.init(result) // Init self-collection.
+			return result
+		}),
+	}
+}
+
+// GetMetricWithLabelValues returns the Counter for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Counter is created.
+//
+// It is possible to call this method without using the returned Counter to only
+// create the new Counter but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Counter for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Counter from the CounterVec. In that case,
+// the Counter will still exist, but it will not be exported anymore, even if a
+// Counter with the same label values is created later.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// GetMetricWith returns the Counter for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Counter is created. Implications of
+// creating a Counter without using it and keeping the Counter for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (v *CounterVec) WithLabelValues(lvs ...string) Counter {
+	c, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
+func (v *CounterVec) With(labels Labels) Counter {
+	c, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the CounterVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &CounterVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
+}
+
+// CounterFunc is a Counter whose value is determined at collect time by calling a
+// provided function.
+//
+// To create CounterFunc instances, use NewCounterFunc.
+type CounterFunc interface {
+	Metric
+	Collector
+}
+
+// NewCounterFunc creates a new CounterFunc based on the provided
+// CounterOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a CounterFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe. The function should also honor
+// the contract for a Counter (values only go up, not down), but compliance will
+// not be checked.
+func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), CounterValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/desc.go

@@ -0,0 +1,184 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/model"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Desc is the descriptor used by every Prometheus Metric. It is essentially
+// the immutable meta-data of a Metric. The normal Metric implementations
+// included in this package manage their Desc under the hood. Users only have to
+// deal with Desc if they use advanced features like the ExpvarCollector or
+// custom Collectors and Metrics.
+//
+// Descriptors registered with the same registry have to fulfill certain
+// consistency and uniqueness criteria if they share the same fully-qualified
+// name: They must have the same help string and the same label names (aka label
+// dimensions) in each, constLabels and variableLabels, but they must differ in
+// the values of the constLabels.
+//
+// Descriptors that share the same fully-qualified names and the same label
+// values of their constLabels are considered equal.
+//
+// Use NewDesc to create new Desc instances.
+type Desc struct {
+	// fqName has been built from Namespace, Subsystem, and Name.
+	fqName string
+	// help provides some helpful information about this metric.
+	help string
+	// constLabelPairs contains precalculated DTO label pairs based on
+	// the constant labels.
+	constLabelPairs []*dto.LabelPair
+	// VariableLabels contains names of labels for which the metric
+	// maintains variable values.
+	variableLabels []string
+	// id is a hash of the values of the ConstLabels and fqName. This
+	// must be unique among all registered descriptors and can therefore be
+	// used as an identifier of the descriptor.
+	id uint64
+	// dimHash is a hash of the label names (preset and variable) and the
+	// Help string. Each Desc with the same fqName must have the same
+	// dimHash.
+	dimHash uint64
+	// err is an error that occurred during construction. It is reported on
+	// registration time.
+	err error
+}
+
+// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
+// and will be reported on registration time. variableLabels and constLabels can
+// be nil if no such labels should be set. fqName must not be empty.
+//
+// variableLabels only contain the label names. Their label values are variable
+// and therefore not part of the Desc. (They are managed within the Metric.)
+//
+// For constLabels, the label values are constant. Therefore, they are fully
+// specified in the Desc. See the Collector example for a usage pattern.
+func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
+	d := &Desc{
+		fqName:         fqName,
+		help:           help,
+		variableLabels: variableLabels,
+	}
+	if !model.IsValidMetricName(model.LabelValue(fqName)) {
+		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
+		return d
+	}
+	// labelValues contains the label values of const labels (in order of
+	// their sorted label names) plus the fqName (at position 0).
+	labelValues := make([]string, 1, len(constLabels)+1)
+	labelValues[0] = fqName
+	labelNames := make([]string, 0, len(constLabels)+len(variableLabels))
+	labelNameSet := map[string]struct{}{}
+	// First add only the const label names and sort them...
+	for labelName := range constLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
+			return d
+		}
+		labelNames = append(labelNames, labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	sort.Strings(labelNames)
+	// ... so that we can now add const label values in the order of their names.
+	for _, labelName := range labelNames {
+		labelValues = append(labelValues, constLabels[labelName])
+	}
+	// Validate the const label values. They can't have a wrong cardinality, so
+	// use in len(labelValues) as expectedNumberOfValues.
+	if err := validateLabelValues(labelValues, len(labelValues)); err != nil {
+		d.err = err
+		return d
+	}
+	// Now add the variable label names, but prefix them with something that
+	// cannot be in a regular label name. That prevents matching the label
+	// dimension with a different mix between preset and variable labels.
+	for _, labelName := range variableLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
+			return d
+		}
+		labelNames = append(labelNames, "$"+labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	if len(labelNames) != len(labelNameSet) {
+		d.err = errors.New("duplicate label names")
+		return d
+	}
+
+	vh := hashNew()
+	for _, val := range labelValues {
+		vh = hashAdd(vh, val)
+		vh = hashAddByte(vh, separatorByte)
+	}
+	d.id = vh
+	// Sort labelNames so that order doesn't matter for the hash.
+	sort.Strings(labelNames)
+	// Now hash together (in this order) the help string and the sorted
+	// label names.
+	lh := hashNew()
+	lh = hashAdd(lh, help)
+	lh = hashAddByte(lh, separatorByte)
+	for _, labelName := range labelNames {
+		lh = hashAdd(lh, labelName)
+		lh = hashAddByte(lh, separatorByte)
+	}
+	d.dimHash = lh
+
+	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
+	for n, v := range constLabels {
+		d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(v),
+		})
+	}
+	sort.Sort(labelPairSorter(d.constLabelPairs))
+	return d
+}
+
+// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the
+// provided error set. If a collector returning such a descriptor is registered,
+// registration will fail with the provided error. NewInvalidDesc can be used by
+// a Collector to signal inability to describe itself.
+func NewInvalidDesc(err error) *Desc {
+	return &Desc{
+		err: err,
+	}
+}
+
+func (d *Desc) String() string {
+	lpStrings := make([]string, 0, len(d.constLabelPairs))
+	for _, lp := range d.constLabelPairs {
+		lpStrings = append(
+			lpStrings,
+			fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()),
+		)
+	}
+	return fmt.Sprintf(
+		"Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}",
+		d.fqName,
+		d.help,
+		strings.Join(lpStrings, ","),
+		d.variableLabels,
+	)
+}

vendor/github.com/prometheus/client_golang/prometheus/doc.go

@@ -0,0 +1,201 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package prometheus is the core instrumentation package. It provides metrics
+// primitives to instrument code for monitoring. It also offers a registry for
+// metrics. Sub-packages allow to expose the registered metrics via HTTP
+// (package promhttp) or push them to a Pushgateway (package push). There is
+// also a sub-package promauto, which provides metrics constructors with
+// automatic registration.
+//
+// All exported functions and methods are safe to be used concurrently unless
+// specified otherwise.
+//
+// A Basic Example
+//
+// As a starting point, a very basic usage example:
+//
+//    package main
+//
+//    import (
+//    	"log"
+//    	"net/http"
+//
+//    	"github.com/prometheus/client_golang/prometheus"
+//    	"github.com/prometheus/client_golang/prometheus/promhttp"
+//    )
+//
+//    var (
+//    	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
+//    		Name: "cpu_temperature_celsius",
+//    		Help: "Current temperature of the CPU.",
+//    	})
+//    	hdFailures = prometheus.NewCounterVec(
+//    		prometheus.CounterOpts{
+//    			Name: "hd_errors_total",
+//    			Help: "Number of hard-disk errors.",
+//    		},
+//    		[]string{"device"},
+//    	)
+//    )
+//
+//    func init() {
+//    	// Metrics have to be registered to be exposed:
+//    	prometheus.MustRegister(cpuTemp)
+//    	prometheus.MustRegister(hdFailures)
+//    }
+//
+//    func main() {
+//    	cpuTemp.Set(65.3)
+//    	hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc()
+//
+//    	// The Handler function provides a default handler to expose metrics
+//    	// via an HTTP server. "/metrics" is the usual endpoint for that.
+//    	http.Handle("/metrics", promhttp.Handler())
+//    	log.Fatal(http.ListenAndServe(":8080", nil))
+//    }
+//
+//
+// This is a complete program that exports two metrics, a Gauge and a Counter,
+// the latter with a label attached to turn it into a (one-dimensional) vector.
+//
+// Metrics
+//
+// The number of exported identifiers in this package might appear a bit
+// overwhelming. However, in addition to the basic plumbing shown in the example
+// above, you only need to understand the different metric types and their
+// vector versions for basic usage. Furthermore, if you are not concerned with
+// fine-grained control of when and how to register metrics with the registry,
+// have a look at the promauto package, which will effectively allow you to
+// ignore registration altogether in simple cases.
+//
+// Above, you have already touched the Counter and the Gauge. There are two more
+// advanced metric types: the Summary and Histogram. A more thorough description
+// of those four metric types can be found in the Prometheus docs:
+// https://prometheus.io/docs/concepts/metric_types/
+//
+// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the
+// Prometheus server not to assume anything about its type.
+//
+// In addition to the fundamental metric types Gauge, Counter, Summary,
+// Histogram, and Untyped, a very important part of the Prometheus data model is
+// the partitioning of samples along dimensions called labels, which results in
+// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
+// HistogramVec, and UntypedVec.
+//
+// While only the fundamental metric types implement the Metric interface, both
+// the metrics and their vector versions implement the Collector interface. A
+// Collector manages the collection of a number of Metrics, but for convenience,
+// a Metric can also “collect itself”. Note that Gauge, Counter, Summary,
+// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec,
+// SummaryVec, HistogramVec, and UntypedVec are not.
+//
+// To create instances of Metrics and their vector versions, you need a suitable
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
+// UntypedOpts.
+//
+// Custom Collectors and constant Metrics
+//
+// While you could create your own implementations of Metric, most likely you
+// will only ever implement the Collector interface on your own. At a first
+// glance, a custom Collector seems handy to bundle Metrics for common
+// registration (with the prime example of the different metric vectors above,
+// which bundle all the metrics of the same name but with different labels).
+//
+// There is a more involved use case, too: If you already have metrics
+// available, created outside of the Prometheus context, you don't need the
+// interface of the various Metric types. You essentially want to mirror the
+// existing numbers into Prometheus Metrics during collection. An own
+// implementation of the Collector interface is perfect for that. You can create
+// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
+// NewConstSummary (and their respective Must… versions). That will happen in
+// the Collect method. The Describe method has to return separate Desc
+// instances, representative of the “throw-away” metrics to be created later.
+// NewDesc comes in handy to create those Desc instances. Alternatively, you
+// could return no Desc at all, which will marke the Collector “unchecked”.  No
+// checks are porformed at registration time, but metric consistency will still
+// be ensured at scrape time, i.e. any inconsistencies will lead to scrape
+// errors. Thus, with unchecked Collectors, the responsibility to not collect
+// metrics that lead to inconsistencies in the total scrape result lies with the
+// implementer of the Collector. While this is not a desirable state, it is
+// sometimes necessary. The typical use case is a situatios where the exact
+// metrics to be returned by a Collector cannot be predicted at registration
+// time, but the implementer has sufficient knowledge of the whole system to
+// guarantee metric consistency.
+//
+// The Collector example illustrates the use case. You can also look at the
+// source code of the processCollector (mirroring process metrics), the
+// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar
+// metrics) as examples that are used in this package itself.
+//
+// If you just need to call a function to get a single float value to collect as
+// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting
+// shortcuts.
+//
+// Advanced Uses of the Registry
+//
+// While MustRegister is the by far most common way of registering a Collector,
+// sometimes you might want to handle the errors the registration might cause.
+// As suggested by the name, MustRegister panics if an error occurs. With the
+// Register function, the error is returned and can be handled.
+//
+// An error is returned if the registered Collector is incompatible or
+// inconsistent with already registered metrics. The registry aims for
+// consistency of the collected metrics according to the Prometheus data model.
+// Inconsistencies are ideally detected at registration time, not at collect
+// time. The former will usually be detected at start-up time of a program,
+// while the latter will only happen at scrape time, possibly not even on the
+// first scrape if the inconsistency only becomes relevant later. That is the
+// main reason why a Collector and a Metric have to describe themselves to the
+// registry.
+//
+// So far, everything we did operated on the so-called default registry, as it
+// can be found in the global DefaultRegisterer variable. With NewRegistry, you
+// can create a custom registry, or you can even implement the Registerer or
+// Gatherer interfaces yourself. The methods Register and Unregister work in the
+// same way on a custom registry as the global functions Register and Unregister
+// on the default registry.
+//
+// There are a number of uses for custom registries: You can use registries with
+// special properties, see NewPedanticRegistry. You can avoid global state, as
+// it is imposed by the DefaultRegisterer. You can use multiple registries at
+// the same time to expose different metrics in different ways.  You can use
+// separate registries for testing purposes.
+//
+// Also note that the DefaultRegisterer comes registered with a Collector for Go
+// runtime metrics (via NewGoCollector) and a Collector for process metrics (via
+// NewProcessCollector). With a custom registry, you are in control and decide
+// yourself about the Collectors to register.
+//
+// HTTP Exposition
+//
+// The Registry implements the Gatherer interface. The caller of the Gather
+// method can then expose the gathered metrics in some way. Usually, the metrics
+// are served via HTTP on the /metrics endpoint. That's happening in the example
+// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
+// (The top-level functions in the prometheus package are deprecated.)
+//
+// Pushing to the Pushgateway
+//
+// Function for pushing to the Pushgateway can be found in the push sub-package.
+//
+// Graphite Bridge
+//
+// Functions and examples to push metrics from a Gatherer to Graphite can be
+// found in the graphite sub-package.
+//
+// Other Means of Exposition
+//
+// More ways of exposing metrics can easily be added by following the approaches
+// of the existing implementations.
+package prometheus