proxy: Add an interface for user role assignment

This moves the lookup and the creation of the users' role assignemt out
of the user backend into its own interface. This makes the user backend
a bit simpler and allows to provide different implemenation for the user
role assignment more easily.

services/proxy/pkg/command/server.go

@@ -31,6 +31,7 @@ import (
 	proxyHTTP "github.com/owncloud/ocis/v2/services/proxy/pkg/server/http"
 	"github.com/owncloud/ocis/v2/services/proxy/pkg/tracing"
 	"github.com/owncloud/ocis/v2/services/proxy/pkg/user/backend"
+	"github.com/owncloud/ocis/v2/services/proxy/pkg/userroles"
 	"github.com/urfave/cli/v2"
 	"golang.org/x/oauth2"
 )
@@ -149,7 +150,6 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 
 		userProvider = backend.NewCS3UserBackend(
 			backend.WithLogger(logger),
-			backend.WithRoleService(rolesClient),
 			backend.WithRevaAuthenticator(revaClient),
 			backend.WithMachineAuthAPIKey(cfg.MachineAuthAPIKey),
 			backend.WithOIDCissuer(cfg.OIDC.Issuer),
@@ -159,6 +159,11 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 		logger.Fatal().Msgf("Invalid accounts backend type '%s'", cfg.AccountBackend)
 	}
 
+	roleAssigner := userroles.NewDefaultRoleAssigner(
+		userroles.WithRoleService(rolesClient),
+		userroles.WithLogger(logger),
+	)
+
 	storeClient := storesvc.NewStoreService("com.owncloud.api.store", grpc.DefaultClient())
 	if err != nil {
 		logger.Error().Err(err).
@@ -210,6 +215,7 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 		Logger:             logger,
 		PreSignedURLConfig: cfg.PreSignedURL,
 		UserProvider:       userProvider,
+		UserRoleAssigner:   roleAssigner,
 		Store:              storeClient,
 	})
 
@@ -236,6 +242,7 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 		middleware.AccountResolver(
 			middleware.Logger(logger),
 			middleware.UserProvider(userProvider),
+			middleware.UserRoleAssigner(roleAssigner),
 			middleware.TokenManagerConfig(*cfg.TokenManager),
 			middleware.UserOIDCClaim(cfg.UserOIDCClaim),
 			middleware.UserCS3Claim(cfg.UserCS3Claim),