Add OIDC role sync config (OIDC_ADMIN_GROUP_NAME, OIDC_GROUPS_CLAIM)

Mv.OidcRoleSyncConfig reads from config; runtime.exs overrides from ENV in prod.

config/config.exs

@@ -58,6 +58,11 @@ config :mv,
     max_rows: 1000
   ]
 
+# OIDC group → role sync (optional). Overridden in runtime.exs from ENV in production.
+config :mv, :oidc_role_sync,
+  admin_group_name: nil,
+  groups_claim: "groups"
+
 # Configures the endpoint
 config :mv, MvWeb.Endpoint,
   url: [host: "localhost"],

config/runtime.exs

@@ -153,6 +153,11 @@ if config_env() == :prod do
     client_secret: client_secret,
     redirect_uri: System.get_env("OIDC_REDIRECT_URI") || default_redirect_uri
 
+  # OIDC group → Admin role sync (optional). Groups claim default "groups".
+  config :mv, :oidc_role_sync,
+    admin_group_name: System.get_env("OIDC_ADMIN_GROUP_NAME"),
+    groups_claim: System.get_env("OIDC_GROUPS_CLAIM") || "groups"
+
   # Token signing secret from environment variable
   # This overrides the placeholder value set in prod.exs
   # Supports TOKEN_SIGNING_SECRET or TOKEN_SIGNING_SECRET_FILE for Docker secrets.

lib/mv/oidc_role_sync_config.ex

@@ -0,0 +1,24 @@
+defmodule Mv.OidcRoleSyncConfig do
+  @moduledoc """
+  Runtime configuration for OIDC group → role sync (e.g. admin group → Admin role).
+
+  Reads from Application config `:mv, :oidc_role_sync`:
+  - `:admin_group_name` – OIDC group name that maps to Admin role (optional; when nil, no sync).
+  - `:groups_claim` – JWT/user_info claim name for groups (default: `"groups"`).
+
+  Set via ENV in production: OIDC_ADMIN_GROUP_NAME, OIDC_GROUPS_CLAIM (see config/runtime.exs).
+  """
+  @doc "Returns the OIDC group name that maps to Admin role, or nil if not configured."
+  def oidc_admin_group_name do
+    get(:admin_group_name)
+  end
+
+  @doc "Returns the JWT/user_info claim name for groups; defaults to \"groups\"."
+  def oidc_groups_claim do
+    get(:groups_claim) || "groups"
+  end
+
+  defp get(key) do
+    Application.get_env(:mv, :oidc_role_sync, []) |> Keyword.get(key)
+  end
+end

test/mv/oidc_role_sync_config_test.exs

@@ -0,0 +1,49 @@
+defmodule Mv.OidcRoleSyncConfigTest do
+  @moduledoc """
+  Tests for OIDC role sync configuration (OIDC_ADMIN_GROUP_NAME, OIDC_GROUPS_CLAIM).
+  """
+  use ExUnit.Case, async: false
+
+  alias Mv.OidcRoleSyncConfig
+
+  describe "oidc_admin_group_name/0" do
+    test "returns nil when OIDC_ADMIN_GROUP_NAME is not configured" do
+      restore = put_config(admin_group_name: nil)
+      on_exit(restore)
+
+      assert OidcRoleSyncConfig.oidc_admin_group_name() == nil
+    end
+
+    test "returns configured admin group name when set" do
+      restore = put_config(admin_group_name: "mila-admin")
+      on_exit(restore)
+
+      assert OidcRoleSyncConfig.oidc_admin_group_name() == "mila-admin"
+    end
+  end
+
+  describe "oidc_groups_claim/0" do
+    test "returns default \"groups\" when OIDC_GROUPS_CLAIM is not configured" do
+      restore = put_config(groups_claim: nil)
+      on_exit(restore)
+
+      assert OidcRoleSyncConfig.oidc_groups_claim() == "groups"
+    end
+
+    test "returns configured claim name when OIDC_GROUPS_CLAIM is set" do
+      restore = put_config(groups_claim: "ak_groups")
+      on_exit(restore)
+
+      assert OidcRoleSyncConfig.oidc_groups_claim() == "ak_groups"
+    end
+  end
+
+  defp put_config(opts) do
+    current = Application.get_env(:mv, :oidc_role_sync, [])
+    Application.put_env(:mv, :oidc_role_sync, Keyword.merge(current, opts))
+
+    fn ->
+      Application.put_env(:mv, :oidc_role_sync, current)
+    end
+  end
+end