介绍
由于项目组需求、最近在研究消息推送服务平台、结合业务和使用场景分析最终选择的是 Mosquitto 消息服务器、 Mosquitto 服务器的安装、配置、集群搭建 我就不在这多说了、有兴趣的可以看我对 Mosquitto 学习记录的前七篇文章。 今天在这住要介绍网页版 WebSockets 实现消息的推送。
1: 本 SDK 的开发 是基于 eclipse.paha.javaScript 包来实现的。
2: 引入开发需要的JavaScript
<script src="https://cdnjs.cloudflare.com/ajax/libs/paho-mqtt/1.0.1/mqttws31.js" type="text/javascript"></script>
注： 此文件可以到官网下载、 地址：https://raw.githubusercontent.com/eclipse/paho.mqtt.javascript/master/src/mqttws31.js
3: 分装实现 js - sdk
var websocket = function(config) {this.host = config.host;// ip this.port = config.port;// 端口this.useTLS = config.useTLS; // 是否启用TLS 安全连接this.topic = config.topic;// 订阅Topicthis.userName = config.userName; // 连接用户名this.password = config.password; // 密码this.cleansession = config.cleansession; //false : 表示每次相同的身份登陆： true ： 表示每次以新身份登陆 this.reconnectTimeout = 5000; // 重试超时时间this.clientId = config.clientId; // 客户端名称var mqttClient;this.connect = function MQTTconnect() {mqttClient = new Paho.MQTT.Client(this.host, this.port, clientId);var options = {timeout : 10,useSSL : this.useTLS,cleanSession : this.cleansession,onSuccess : onConnect,onFailure : function(message) {faildMssge(message.errorMessage, "Retrying",fialdMessageCallback)setTimeout(MQTTconnect, this.reconnectTimeout);}};mqttClient.onConnectionLost = onConnectionLost;mqttClient.onMessageArrived = onMessageArrived;if (this.userName != null) {options.userName = this.userName;options.password = this.password;}console.log("Host=" + host + ", port=" + port + " TLS = " + useTLS+ " username=" + userName + " password=" + password);mqttClient.connect(options);}function onConnect() {mqttClient.subscribe(topic, {qos : 0});}function onConnectionLost(response) {setTimeout(MQTTconnect, this.reconnectTimeout);faildMssge("connection lost: " + responseObject.errorMessage,". Reconnecting", fialdMessageCallback)};function onMessageArrived(message) {var topic = message.destinationName;var payload = message.payloadString;callback(topic, payload, messageCallback);};function callback(topic, payload, messageCallback) {messageCallback(topic, payload);}function faildMssge(errorMessage, type, fialdMessageCallback) {fialdMessageCallback(errorMessage, type);}this.sendMessage = function sendMessage(topic, message) {var message = new Paho.MQTT.Message(message);message.destinationName = topic;message.qos = 0;mqttClient.send(message);}}4: 使用说明
// Create a config config = {host : ‘172.16.192.103‘,port : 9001,topic : ‘#‘,useTLS : false,userName : null,password : null,cleansession : true,clientId : ‘clientId‘}//Create a client instancevar client = new websocket(config);// connect the clientclient.connect();//send message client.sendMessage(topic, message);// subscribe topic message callback functionfunction messageCallback(topic, payload) {// 业务逻辑处理}//error message callback functionfunction fialdMessageCallback(errorMessage, type) {//业务逻辑处理}到这网页版消息推送基本功能已经实现： 如想要完整的 web 应用实例请到如下地址下载：https://github.com/yuelicn/mqtt-client.git
本人 JavaScript 水平有限、如有不妥的地方欢迎指正 谢谢！
八、网页版消息推送SDK-WebSockets
原文地址：http://www.cnblogs.com/yueli/p/7815093.html