Question: example on how to use inprocgrpc

[iqbalaydrus]

I've been digging the repo for a few hours and have no idea how to use the package. Also read the docs at https://pkg.go.dev/github.com/fullstorydev/grpchan@v1.1.1/inprocgrpc and still has no clue.

Server: https://github.com/grpc/grpc-go/blob/master/examples/helloworld/greeter_server/main.go

// server is used to implement helloworld.GreeterServer.
type server struct {
    pb.UnimplementedGreeterServer
}

// SayHello implements helloworld.GreeterServer
func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
    log.Printf("Received: %v", in.GetName())
    return &pb.HelloReply{Message: "Hello " + in.GetName()}, nil
}

func main() {
    flag.Parse()
    lis, err := net.Listen("tcp", fmt.Sprintf(":%d", *port))
    if err != nil {
        log.Fatalf("failed to listen: %v", err)
    }
    s := grpc.NewServer()
    // pb.RegisterGreeterServer(s, &server{})
        // and then what should I do next?
        inproc := &inprocgrpc.Channel{}
        pb.RegisterGreeterServer(inproc, &server{})
    log.Printf("server listening at %v", lis.Addr())
    if err := s.Serve(lis); err != nil {
        log.Fatalf("failed to serve: %v", err)
    }
}

As for the client I absolutely has no clue how to use that. Can you give me an example on how to use inprocgrpc? Or direct me to some docs if available? Thank you

[joeycumines]

@iqbalaydrus inprocgrpc.Channel implements both grpc.ServiceRegistrar and grpc.ClientConnInterface.

In other words, you can use it directly with the generated stubs, e.g. https://pkg.go.dev/google.golang.org/grpc/examples/helloworld/helloworld#RegisterGreeterServer and https://pkg.go.dev/google.golang.org/grpc/examples/helloworld/helloworld#NewGreeterClient .

[dragonsinth]

@iqbalaydrus inprocgrpc.Channel is mostly used for:

a) writing test cases b) in the rare case that server needs a gRPC channel to itself

Most servers do not need an inproc channel. Are you trying to solve something specific?

[iqbalaydrus]

Ok, so I finally got it working. My usecase is we're building an application in a microservices manner via grpc, but can also be deployed only a single process. I was thinking to use inprocgrpc to have better performance compared to using localhost / in-memory transport if the application deployed to a single process. But weirdly it has slightly worse performance than the said alternatives, or maybe it's expected?

I'm closing this issue since the main question is answered.

[dragonsinth]

Interesting! I am surprised that inprocess channel would have worse performance than a literal TCP connection to the same process, but it's not impossible.

[vominhtrius]

@iqbalaydrus can you describe in more detail the performance of inprocgrc?