Error while trying to read a message in Go client sent by C# server

[gustavokorp]

Hello, I'm trying to make a remote chat between an C# Server and Go Client, but I'm getting this error:

INFO [REMOTE] EndpointReader failed to read error="rpc error: code = Internal desc = grpc: failed to unmarshal the received message proto: cannot parse invalid wire-format data"

It happens when I send a message to my Go client, even using Proto.actor built-in messages I still got this exception, what could be wrong ? I'm pretty sure that there's nothing wrong with the proto message, since I've serialized it to an .bat (in the C# server) then opened and unmarshaled it on my Go client with sucess.

Is there something that I've to add in my Go Client to unmarshal protobuffer messages from C# ? I'm new to Proto.Actor so I wonder if I'm missing something to communicate actors from different languages.

[gavraz]

Hi, The error originates in grpc\stream.go\RecvMsg. I am not sure why it happens, but I noticed another minor issue with the version of grpc we use (1.46.2): The named return value "err" is shadowed by err := recv which implies the defer func does not detect/handle the error. It is probably not related but I thought it is worth noting.

func (ss *serverStream) RecvMsg(m interface{}) (err error) {
	defer func() {
		if ss.trInfo != nil {
			ss.mu.Lock()
			if ss.trInfo.tr != nil {
				if err == nil {
					ss.trInfo.tr.LazyLog(&payload{sent: false, msg: m}, true)
				} else if err != io.EOF {
					ss.trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
					ss.trInfo.tr.SetError()
				}
			}
			ss.mu.Unlock()
		}
		if err != nil && err != io.EOF {
			st, _ := status.FromError(toRPCErr(err))
			ss.t.WriteStatus(ss.s, st)
			// Non-user specified status was sent out. This should be an error
			// case (as a server side Cancel maybe).
			//
			// This is not handled specifically now. User will return a final
			// status from the service handler, we will log that error instead.
			// This behavior is similar to an interceptor.
		}
		if channelz.IsOn() && err == nil {
			ss.t.IncrMsgRecv()
		}
	}()
	var payInfo *payloadInfo
	if ss.statsHandler != nil || ss.binlog != nil {
		payInfo = &payloadInfo{}
	}
	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxReceiveMessageSize, payInfo, ss.decomp); err != nil {
		if err == io.EOF {
			if ss.binlog != nil {
				ss.binlog.Log(&binarylog.ClientHalfClose{})
			}
			return err
		}
		if err == io.ErrUnexpectedEOF {
			err = status.Errorf(codes.Internal, io.ErrUnexpectedEOF.Error())
		}
		return toRPCErr(err)
	}
	if ss.statsHandler != nil {
		ss.statsHandler.HandleRPC(ss.s.Context(), &stats.InPayload{
			RecvTime: time.Now(),
			Payload:  m,
			// TODO truncate large payload.
			Data:       payInfo.uncompressedBytes,
			WireLength: payInfo.wireLength + headerLen,
			Length:     len(payInfo.uncompressedBytes),
		})
	}
	if ss.binlog != nil {
		ss.binlog.Log(&binarylog.ClientMessage{
			Message: payInfo.uncompressedBytes,
		})
	}
	return nil
}

[mhelleborg]

Hi, this is not currently supported. The Go version has not been ported to the latest network protocol as used by the C# version.

[ButterFingerrs]

Hi, this is not currently supported. The Go version has not been ported to the latest network protocol as used by the C# version.

Can we expect an updated Go version? If yes, Can you tell us when can we expect it. If no, Can you suggest any work around( an alternate)

[tgroves-tgiapps]

I think it would be ethical and responsable to the project to not mention that its cross platform. I spent months thinking that its cross platform only to run into this and find that it is not true. I listened to Roger on podcast talking about it being cross platform. It is not true that it is cross platform, at least not yet.