Not clear how to use the generated client implementations

[torkelrogstad]

Thanks for creating what looks like a great, idomatic TS code generator.

However, I'm having some issues getting started. I've generated a TS file from my Proto file, with (among other things), this:

export interface HelloWorldService {
  Ping(request: PingRequest): Promise<PingResponse>;
}

export class HelloWorldServiceClientImpl implements HelloWorldService {
  private readonly rpc: Rpc;
  constructor(rpc: Rpc) {
    this.rpc = rpc;
    this.Ping = this.Ping.bind(this);
  }
  Ping(request: PingRequest): Promise<PingResponse> {
    const data = PingRequest.encode(request).finish();
    const promise = this.rpc.request(
      "helloworld.v1.HelloWorldService",
      "Ping",
      data
    );
    return promise.then((data) => PingResponse.decode(new _m0.Reader(data)));
  }
}

What am I supposed to stick into new HelloWorldServiceClientImpl? The goal here is to create a Node.js client.

[torkelrogstad]

Got this working:

const conn = new grpc.Client(
  "localhost:8765",
  grpc.credentials.createInsecure()
);

type RpcImpl = (
  service: string,
  method: string,
  data: Uint8Array
) => Promise<Uint8Array>;

const sendRequest: RpcImpl = (service, method, data) => {
  // Conventionally in gRPC, the request path looks like
  //   "package.names.ServiceName/MethodName",
  // we therefore construct such a string
  const path = `${service}/${method}`;

  return new Promise((resolve, reject) => {
    // makeUnaryRequest transmits the result (and error) with a callback
    // transform this into a promise!
    const resultCallback: UnaryCallback<any> = (err, res) => {
      if (err) {
        return reject(err);
      }
      resolve(res);
    };

    function passThrough(argument: any) {
      return argument;
    }

    // Using passThrough as the serialize and deserialize functions
    conn.makeUnaryRequest(path, passThrough, passThrough, data, resultCallback);
  });
};

This was not obvious at all. Am I missing something from the documentation, or is there some generated code somewhere I haven't seen?

[torkelrogstad]

I see that if I set outputServices=generic-definitions as an option, I get generated stubs that seems to do everything I need for me. However, I then have to resort to handling responses with callbacks. Is there any reason that the default behavior is to not generate a complete client?

[stephenh]

Hey @torkelrogstad , sorry for the really late follow up here, but right, as you've noticed, ts-proto is not a super-polished / user-friendly / out-of-the-box RPC framework.

Instead, it's more like a swiss-army knife of twirp (originally) / grpc-web / nest / grpc.io / etc. options that has learned to do many different things, but not necessarily any one thing amazingly well. It's strength is in its either configurablility or hackability to fit into custom/bespoke RPC stacks (b/c at least historically the grpc RPC environment was pretty fragmented; it seems like it's becoming less so especially with grpc.io).

This not really on purpose, but just how it's gone.

It'd be great to have a better out-of-box experience; if you want to copy/paste what you have ^ into either a "Getting Started" or "Basic RPC Implementation" section of the readme, or a new dedicated page, that would be really great.

Thank you!

[stephenh]

🎉 This issue has been resolved in version 1.105.2 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[avegancafe]

What is makeUnaryRequest or conn? trying to use this lib and struggling to find a usable grpc web client and I see this example in the docs, but I think might not be fully. Any help or prior context would be greatly appreciated! 🙏 Happy to open a PR with a fully working simple client when I figure one out as well of course

[lf-jason-jia]

Just to mention, the request path should be (at least with grpc-js): /${service}/${method}, so "/" must be in front. Otherwise you would get: Error: 13 INTERNAL: Received RST_STREAM with code 1