golang rpc http

//抄襲一遍，練手

/**
  golang net/rpc   http
*/
package main

import (
	"errors"
	"fmt"
	"log"
	"net"
	"net/http"
	"net/rpc"
	"time"
)

var p = fmt.Println

type Args struct {
	A, B int
}

type Quotient struct {
	Quo, Rem int
}

type Arith int

func (this *Arith) Multiply(args *Args, reply *int) error {
	*reply = args.A * args.B
	return nil
}
func (this *Arith) Divide(args *Args, quo *Quotient) error {
	if args.B == 0 {
		return errors.New("divide by zero")
	}
	quo.Quo = args.A / args.B
	quo.Rem = args.A % args.B

	return nil
}

func main() {
	//server
	arith := new(Arith)
	rpc.Register(arith)
	rpc.HandleHTTP() //DefaultRPCPath
	l, e := net.Listen("tcp", ":1234")
	if e != nil {
		log.Fatal("listen error:", e)
	}
	go http.Serve(l, nil)

	time.Sleep(2 * time.Second)

	//client
	// Synchronous call
	client, err := rpc.DialHTTP("tcp", "127.0.0.1:1234")
	if err != nil {
		log.Fatal("dialing:", err)
	}
	args := &Args{7, 8}
	var reply int
	err = client.Call("Arith.Multiply", args, &reply)
	if err != nil {
		log.Fatal("arith error:", err)
	}
	fmt.Printf("Arith: %d*%d=%d\n", args.A, args.B, reply)

	// Asynchronous call
	quotient := new(Quotient)
	divCall := client.Go("Arith.Divide", args, quotient, nil)
	replyCall := <-divCall.Done // will be equal to divCall
	// check errors, print, etc.
	//7除8 商0 餘7
	p(replyCall.Reply)

	time.Sleep(1 * time.Hour)
	//http://127.0.0.1:1234/debug/rpc
}