服务器与浏览器通信，服务器端需要建立mosca服务和http服务，浏览器端连接到http服务端口
服务器端：
方式一：
var mosca = require(‘mosca‘);
var MqttServer = new mosca.Server({
port: 2000,
http: {
port: 3006,
bundle: true,
static: ‘./‘
}
});
MqttServer.on(‘clientConnected‘, function(client){
console.log(‘client connected‘, client.id);
});
/**
* 监听MQTT主题消息
**/
MqttServer.on(‘published‘, function(packet, client) {
var topic = packet.topic;
console.log(‘message-arrived--->‘,‘topic =‘+topic+‘,message = ‘+ packet.payload.toString());
//MQTT转发主题消息
//MqttServer.publish({topic: ‘test‘, payload: ‘sssss‘});
});
MqttServer.on(‘ready‘, function(){
console.log(‘mqtt is running...‘);
//MqttServer.authenticate = authenticate;
});
方式二：
var http = require(‘http‘)
, httpServ = http.createServer()
, mosca = require(‘mosca‘)
, mqttServ = new mosca.Server({port: 2000});
mqttServ.attachHttpServer(httpServ);
httpServ.listen(3006);
MqttServer.on(‘clientConnected‘, function(client){
console.log(‘client connected‘, client.id);
});
浏览器客户端：//端口为http端口 mqtt://localhost:3006 和 ws://localhost:3006一样,
web页面没有其他要求，没有跨域问题
<!DOCTYPE html>
<!--[if lt IE 7]> <html class="no-js lt-ie9 lt-ie8 lt-ie7"> <![endif]-->
<!--[if IE 7]> <html class="no-js lt-ie9 lt-ie8"> <![endif]-->
<!--[if IE 8]> <html class="no-js lt-ie9"> <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js"> <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title></title>
<meta name="description" content="">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<!--[if lt IE 7]>
<p class="browsehappy">You are using an <strong>outdated</strong> browser. Please <a href="#">upgrade your browser</a> to improve your experience.</p>
<![endif]-->
<div>hello mqtt</div>
<script src="../public/js/jquery-1.9.1.min.js"></script>
<script src="../public/mqtt.min.js"></script>
<script>
////端口为http端口 mqtt://localhost:3006 和 ws://localhost:3006一样
var client = mqtt.connect(‘ws://localhost:3006‘,{
});
// you add a ws:// url here
client.subscribe("mqtt/demo");
client.on(‘connect‘, function () {
console.log(‘connected.....‘);
// client.subscribe(‘test/‘);
// client.publish(‘app2dev/‘, ‘Hello mqtt‘);
});
client.on("message", function (topic, payload) {
alert([topic, payload].join(": "));
})
client.publish("mqtt/demo", "hello world!");
</script>
</body>
</html>
原文：https://www.cnblogs.com/BlingSun/p/8981063.html