make provider config simpler

lib/policy_service/application.ex

@@ -5,12 +5,10 @@ defmodule PolicyService.Application do
 
   use Application
 
-  defp get_zitadel_config(key) do
-    Application.get_env(:policy_service, :zitadel)[key]
-  end
-
   @impl true
   def start(_type, _args) do
+    zitadel_config = Application.get_env(:policy_service, :zitadel, [])
+
     children = [
       PolicyService.CommandedApp,
       PolicyService.Handlers.QuoteRequestHandler,
@@ -25,7 +23,7 @@ defmodule PolicyService.Application do
       {Phoenix.PubSub, name: PolicyService.PubSub, pool_size: 1},
       {Oidcc.ProviderConfiguration.Worker,
        %{
-         issuer: get_zitadel_config(:issuer),
+         issuer: Keyword.get(zitadel_config, :issuer),
          name: PolicyService.ZitadelProvider
        }},
       PolicyServiceWeb.Endpoint

lib/policy_service_web/plugs/authentication_plug.ex

@@ -14,33 +14,20 @@ defmodule PolicyServiceWeb.Plugs.AuthenticationPlug do
 
   ## Options
   - :provider - The OIDCC provider configuration worker name (required)
-  - :client_id - OAuth2 client ID (required) - can be a string or {module, function, args} tuple
-  - :client_secret - OAuth2 client secret (required) - can be a string or {module, function, args} tuple
-  - :required_scopes - List of required scopes (optional)
   """
   def init(opts) do
     provider = Keyword.fetch!(opts, :provider)
-    client_id = Keyword.fetch!(opts, :client_id)
-    client_secret = Keyword.fetch!(opts, :client_secret)
-    required_scopes = Keyword.get(opts, :required_scopes, [])
+
+    zitadel_config = Application.get_env(:policy_service, :zitadel, [])
 
     %{
       provider: provider,
-      client_id: resolve_config(client_id),
-      client_secret: resolve_config(client_secret),
-      required_scopes: required_scopes
+      client_id: Keyword.get(zitadel_config, :client_id),
+      client_secret: Keyword.get(zitadel_config, :client_secret),
+      required_scopes: Keyword.get(zitadel_config, :required_scopes, [])
     }
   end
 
-  defp resolve_config({module, function, args})
-       when is_atom(module) and is_atom(function) and is_list(args) do
-    apply(module, function, args)
-  end
-
-  defp resolve_config(value) when is_binary(value), do: value
-  defp resolve_config(value) when is_function(value, 0), do: value.()
-  defp resolve_config(value), do: value
-
   @doc """
   Authenticates the request by validating the JWT token.
 

lib/policy_service_web/router.ex

@@ -10,10 +10,7 @@ defmodule PolicyServiceWeb.Router do
 
   pipeline :authenticated do
     plug PolicyServiceWeb.Plugs.AuthenticationPlug,
-      provider: PolicyService.ZitadelProvider,
-      client_id: {__MODULE__, :get_zitadel_config, [:client_id]},
-      client_secret: {__MODULE__, :get_zitadel_config, [:client_secret]},
-      required_scopes: {__MODULE__, :get_zitadel_config, [:required_scopes]}
+      provider: PolicyService.ZitadelProvider
   end
 
   pipeline :authorized do
@@ -41,8 +38,4 @@ defmodule PolicyServiceWeb.Router do
   scope "/swaggerui" do
     get "/", OpenApiSpex.Plug.SwaggerUI, path: "/api/openapi"
   end
-
-  def get_zitadel_config(key) do
-    Application.get_env(:policy_service, :zitadel)[key]
-  end
 end