Unable to receive Push messages when using Unity SDK

[LacusCon]

When I use Unity SDK, I can use request and response messages, but I can't receive messages from the server through Session Push. I have already registered through OnRoute

[felipejfc]

can you share a reproduction repo / zip

[LacusCon]

Without using builder.Serializer = protobuf.NewSerializer(), push string is successful. When protobuf is enabled, push string or proto will fail.
[fail code1]
func (s *PushAbout) PushTest(ctx context.Context) (*proto.CommonResp, error) {
resp := &proto.CommonResp{Err: proto.ErrCode_OK}
session := s.app.GetSessionFromCtx(ctx)
_ = session.Push("push.lobby.game_state", resp)
return resp, nil
}
[log1]
level=debug msg="Type=Push, ID=1, UID=, Route=push.lobby.game_state, Data=" source=pitaya
[client not receive]

[fail code2]
func (s *PushAbout) PushTest(ctx context.Context) (*proto.CommonResp, error) {
resp := &proto.CommonResp{Err: proto.ErrCode_OK}
session := s.app.GetSessionFromCtx(ctx)
_ = session.Push("push.lobby.game_state", *resp)
return resp, nil
}
[log2]
level=debug msg="Type=Push, ID=1, UID=, Route=push.lobby.game_state, Data={state:{NoUnkeyedLiterals:{} DoNotCompare:[] DoNotCopy:[] atomicMessageInfo:} sizeCache:0 unknownFields:[] Err:OK}" source=pitaya
[client log]
PIT-000 %protobuf: convert on wrong type value

[LacusCon]

I found the cause of this problem. It was caused by Marshal(m Message) ([]byte, error). If the proto message uses the default value, there will be a problem.
enum ErrCode {
OK = 0;
ERR = 1;
}
message CommonResp {
ErrCode err = 1;
}
[code]:
resp1 := &proto.CommonResp{Err: proto.ErrCode_OK}
session.Push("test.x.y", resp1)
[failed]:

[code]:
resp2 := &proto.CommonResp{Err: proto.ErrCode_ERR}
session.Push("test.x.y", resp2)
[success]:

[filipemeneses]

I had a similar issue with SendPushToUsers, an empty proto message doesn't throw any exceptions nor calls the client listener, to fix this, I added an arbitrary attribute called status to the proto and worked

// base.proto

syntax = "proto3";

package protos;

message MyResponse {
+  bool status = 1;
}

// usage.go
pushResponse := &protos.MyResponse{
+  Status: true,
}

pitayaInstance.SendPushToUsers("myRoute", pushResponse, myUsers, "myType")

[renatoaf]

We went through this recently in one of our projects. The problem is in the libpitaya c code: https://github.com/topfreegames/libpitaya/blob/master/src/pc_trans.c#L244

Zero-length messages are ignored on pushes, so it never reaches the C# code where messages would be unmarshalled / callbacks invoked.