A minimal python to go json-rpc implemention, sans HTTP

client.py

import json
import socket

s = socket.create_connection(("127.0.0.1", 5090))
s.sendall(json.dumps(({"id": 1, "method": "Hello.Hello", "params": ["hello"]})))
print s.recv(4096)

oclient.py

import json
import socket
import itertools

class RPCClient(object):

    def __init__(self, addr, codec=json):
        self._socket = socket.create_connection(addr)
        self._id_iter = itertools.count()
        self._codec = codec

    def _message(self, name, *params):
        return dict(id=self._id_iter.next(),
                    params=list(params),
                    method=name)

    def call(self, name, *params):
        req = self._message(name, *params)
        id = req.get('id')

        mesg = self._codec.dumps(req)
        self._socket.sendall(mesg)

        # This will actually have to loop if resp is bigger
        resp = self._socket.recv(4096)
        resp = self._codec.loads(resp)

        if resp.get('id') != id:
            raise Exception("expected id=%s, received id=%s: %s"
                            %(id, resp.get('id'), resp.get('error')))

        if resp.get('error') is not None:
            raise Exception(resp.get('error'))

        return resp.get('result')

    def close(self):
        self._socket.close()

rpc = RPCClient(("127.0.0.1", 5090))

for i in xrange(10000):
    print rpc.call("Hello.Hello", "hello")

server.go

package main

import (
	"net"
	"log"
	"os"
	"rpc"
	"rpc/jsonrpc"
)

type Hello int

func (h *Hello) Hello(arg *string, reply *string) os.Error {
	log.Println("received:", *arg)
	*reply = "hello"
	return nil
}

func main() {
	l, err := net.Listen("tcp", "127.0.0.1:5090")
	defer l.Close()

	if err != nil {
		log.Fatal(err)
	}

	log.Print("listening:", l.Addr())

	hello := new(Hello)
	rpc.Register(hello)

	for {
		log.Print("waiting for connections...")
		c, err := l.Accept()

		if err != nil {
			log.Printf("accept error: %s", c)
			continue
		}

		log.Printf("connection started: %v", c.RemoteAddr())
		go jsonrpc.ServeConn(c)
	}
}