grpc-json starts an HTTP server and serves GRPC methods as JSON.

Quickstart

This will start an HTTP server on port 8080:

go grpcj.Serve(&myGRPCServer{})

Options can be set like this:

go grpcj.Serve(&myGRPCServer{}, grpcj.Port(":8080"), grpcj.Timeout(30*time.Second))

Overview

This package uses reflection to discover all your RPC methods and automatically unmarshal the JSON requests and pass them to the proper RPC method. POSTing to http://mydomain/MyRPCMethodName will call the corresponding RPC method.

For example, if you have the following proto definition:

service MyService {
    rpc Add(AddRequest) returns (AddResponse) {}
}

message AddRequest {
    int64 num_one = 1;
    int64 num_two = 2;
}

message AddResponse {
    int64 sum = 1;
}

and the following golang implementation:

type server struct{}

func (server *server) Add(ctx context.Context, req *pb.AddRequest) (*pb.AddResponse, error) {
    resp := &pb.AddResponse{
        Sum: req.NumOne + req.NumTwo,
    }
    return resp, nil
}

grpcj.Serve(&server{})

simply POST a JSON payload of {"num_one": 1, "num_two": 1} to localhost:8080/Add and you will receive a response of {"sum": 2}.

See the godocs for more information.

Goodies

• grpc-json implements a slightly modified version of the standard protobuf jsobpb Marshaler that allows returning Int64 and Uint64 as numbers instead of strings.
• grpc-json will gracefully shut down using the http.Server Shutdown. Since grpc-json is commonly run in a goroutine and since the caller may not be catching the exit signal themselves, grpc-json will re-emit the signal after having gracefully shutdown.
• GET requests will be handled using the github.com/joncalhoun/qson lib.