README.md

rpcmq

Introduction

The package rpcmq implements an RPC protocol over AMQP.

Installation

go get github.com/jroimartin/rpcmq

Documentation

godoc github.com/jroimartin/rpcmq

Examples

The following snippets show how easy is to implement both an RPC client and server using rpcmq. In this example the server registers a new method called "toUpper" that takes an string and convert it to uppercase. On the other hand, the RPC client will invoke this method remotely. Then, after 10 seconds, the client and the server will shutdown.

server.go

package main

import (
	"log"
	"strings"
	"time"

	"github.com/jroimartin/rpcmq"
)

func main() {
	s := rpcmq.NewServer("amqp://amqp_broker:5672",
		"rpc-queue", "rpc-exchange", "direct")
	if err := s.Register("toUpper", toUpper); err != nil {
		log.Fatalf("Register: %v", err)
	}
	if err := s.Init(); err != nil {
		log.Fatalf("Init: %v", err)
	}
	defer s.Shutdown()

	time.Sleep(1 * time.Minute)
}

func toUpper(id string, data []byte) ([]byte, error) {
	log.Printf("Received (%v): toUpper(%v)\n", id, string(data))
	return []byte(strings.ToUpper(string(data))), nil
}

client.go

package main

import (
	"log"
	"time"

	"github.com/jroimartin/rpcmq"
)

func main() {
	c := rpcmq.NewClient("amqp://amqp_broker:5672",
		"rpc-queue", "rpc-client", "rpc-exchange", "direct")
	if err := c.Init(); err != nil {
		log.Fatalf("Init: %v", err)
	}
	defer c.Shutdown()

	go func() {
		for {
			data := []byte("Hello gophers!")
			uuid, err := c.Call("toUpper", data, 0)
			if err != nil {
				log.Println("Call:", err)
			}
			log.Printf("Sent: toUpper(%v) (%v)\n", string(data), uuid)
			time.Sleep(500 * time.Millisecond)
		}
	}()

	go func() {
		for r := range c.Results() {
			if r.Err != "" {
				log.Printf("Received error: %v (%v)", r.Err, r.UUID)
				continue
			}
			log.Printf("Received: %v (%v)\n", string(r.Data), r.UUID)
		}
	}()

	time.Sleep(1 * time.Minute)
}

This code will generate the following output: