Go语言连接测试EMQTT

前言：

首先安装EMQTT服务器，参考上一篇

本文测试方法：

使用Go语言调用客户端（paho.mqtt.golang）API向EMQTT服务器发消息

测试步骤：

1、下载客户端库

https://github.com/eclipse/paho.mqtt.golang

2、测试代码

package main

import (
	"fmt"
	"log"
	"os"
	"time"

	"github.com/eclipse/paho.mqtt.golang"
)

	//set callback function
var f mqtt.MessageHandler = func(client mqtt.Client, msg mqtt.Message) {
	fmt.Printf("TOPIC: %sn", msg.Topic())
	fmt.Printf("MSG: %sn", msg.Payload())
}

func main() {
	mqtt.DEBUG = log.New(os.Stdout, "", 0)
	mqtt.ERROR = log.New(os.Stdout, "", 0)

	//connect mqtt-server and set clientID
	opts := mqtt.NewClientOptions().AddBroker("tcp://localhost:1883").SetClientID("mqtt_client")

	//set userName
	opts.SetUsername("mqtt_test")
	opts.SetKeepAlive(2 * time.Second)
	opts.SetDefaultPublishHandler(f)
	opts.SetPingTimeout(1 * time.Second)

	//create object
	c := mqtt.NewClient(opts)
	if token := c.Connect(); token.Wait() && token.Error() != nil {
		panic(token.Error())
	}

	//subscribe topic
	if token := c.Subscribe("go-mqtt/sample", 0, nil); token.Wait() && token.Error() != nil {
		fmt.Println(token.Error())
		os.Exit(1)
	}

	//publish topic
	for i := 0; i <5; i++ {
		text := fmt.Sprintf("this is msg #%d!", i)
		token := c.Publish("go-mqtt/sample", 0, false, text)
		token.Wait()
	}

	//unsubscribe topic
	time.Sleep(6 * time.Second)

	if token := c.Unsubscribe("go-mqtt/sample"); token.Wait() && token.Error() != nil {
		fmt.Println(token.Error())
		os.Exit(1)
	}

	c.Disconnect(250)

	time.Sleep(1 * time.Second)
}

3、服务器查看消息接受情况