vikunja-api/vendor/github.com/go-redis/redis/v7/internal/consistenthash/consistenthash.go
konrad d28f005552 Update xorm to v1 (#323)
Fix limit for databases other than sqlite

go mod tidy && go mod vendor

Remove unneeded break statements

Make everything work with the new xorm version

Fix xorm logging

Fix lint

Fix redis init

Fix using id field

Fix database init for testing

Change default database log level

Add xorm logger

Use const for postgres

go mod tidy

Merge branch 'master' into update/xorm

# Conflicts:
#	go.mod
#	go.sum
#	vendor/modules.txt

go mod vendor

Fix loading fixtures for postgres

Go mod vendor1

Update xorm to version 1

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/323
2020-04-12 17:29:24 +00:00

81 lines
1.8 KiB
Go

/*
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]]
}