Can C data be sent out through grpc stream.Send() without calling unmarshal?

[Steven Jiang]

The message has to be constructed in C code.  My current implementation is :

  1. construct grpc message in C and pass it as bytes to GO code through channel;

  2. in Go code, call proto.unmarshal to get grpc message;

  3.  Send the grpc message out via stream.Send(grpcmsg)

What we want is to skip this unmarshal because we've already constructed the grpc message in C.  Is there any way to do a type cast thing to skip unmarshal?

Thanks

Steven

[Kun Zhang]

It sounds like the real question is that how to send already serialized message in Go.

[Doug Fawley]

Yes, you can do this!  You need to use a custom codec and use the native grpc API instead of the proto-generated one.  Example:

Codec definition (basically pass-through):

https://github.com/grpc/grpc-go/blob/master/benchmark/worker/main.go#L46

Install it in the client when dialing:

https://godoc.org/google.golang.org/grpc#WithCodec

https://github.com/grpc/grpc-go/blob/master/benchmark/worker/benchmark_client.go#L143

And then call send with a []byte:

https://github.com/grpc/grpc-go/blob/master/benchmark/benchmark.go#L225

Let me know if any of that is not clear.

 

Thanks,

Doug

[Steven Jiang]

Thanks for the detailed reply, Doug. There is still one issue in my case:

If it's a dialout connection, I can change the dialOption.  But in my case, the connection is not created by me but by grpc client. I just send back the response.

Is there any way to change the codec of the connection initiated by grpc client?

Regards

Steven