Generating a gRPC Service

    ent/schema/user.go

    Now re-run code-generation:

    1. go generate ./...

    First, entproto added a service definition to entpb.proto:

    ent/proto/entpb/entpb.proto

    1. service UserService {
    2.   rpc Create ( CreateUserRequest ) returns ( User );
    4.   rpc Get ( GetUserRequest ) returns ( User );
    6.   rpc Update ( UpdateUserRequest ) returns ( User );
    10.   rpc List ( ListUserRequest ) returns ( ListUserResponse );
    12. }

    ent/proto/entpb/entpb_grpc.pb.go

    The second file, entpub_user_service.go contains a generated implementation for this interface. For example, an implementation for the Get method:

    1. // Get implements UserServiceServer.Get
    2. func (svc *UserService) Get(ctx context.Context, req *GetUserRequest) (*User, error) {
    3.     var (
    4.         err error
    5.         get *ent.User
    6.     )
    7.     id := int(req.GetId())
    8.     switch req.GetView() {
    10.         get, err = svc.client.User.Get(ctx, id)
    11.     case GetUserRequest_WITH_EDGE_IDS:
    12.             Where(user.ID(id)).
    13.             Only(ctx)
    14.     default:
    15.         return nil, status.Error(codes.InvalidArgument, "invalid argument: unknown view")
    16.     }
    17.     switch {
    18.     case err == nil:
    19.         return toProtoUser(get)
    20.     case ent.IsNotFound(err):
    21.         return nil, status.Errorf(codes.NotFound, "not found: %s", err)
    22.     default:
    23.         return nil, status.Errorf(codes.Internal, "internal error: %s", err)

    Not bad! Next, let’s create a gRPC server that can serve requests to our service.