return
	}
	// Store the port for test only.
	s.grpcPort <- listener.Addr().(*net.TCPAddr).Port

	s.grpcServer = grpc.NewServer()
	authv2.RegisterAuthorizationServer(s.grpcServer, s.grpcV2)
	authv3.RegisterAuthorizationServer(s.grpcServer, s.grpcV3)

	log.Printf("Starting gRPC server at %s", listener.Addr())
	if err := s.grpcServer.Serve(listener); err != nil {