node.js和socket.io纯js实现的即时通讯实例分享
在这个例子中，其实node.js并没有真正起到服务器的作用，因为我们这里可以直接运行client.html文件，而不用输入url请求，当然，要想输入url请求页面内容还需要加入请求静态文件的代码。这个实例中node.js最重要的作用就是将服务端迁移到了js，实现了客户端和服务端语言上的统一，我们只要在浏览器上同时运行两个client.html客户端页面，即可进行简单的即是通讯了，socket.io才是我们真正用来实现即时通讯的消息的收发。
var server = http.createServer(callback);//开启http服务
var io = require("socket.io").listen(server);//socketio来监听http服务器
接下来直接上客户端代码client.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>socketIO - Simple chat</title>
<script src="./socketio.js"></script>
<style>
* { font-family:tahoma; font-size:12px; padding:0px; margin:0px; }
p { line-height:18px; }
div { }
.textInput{width:500px;margin: 0 auto;margin-top: 50px;}
#content { padding:5px; background:#ddd; border-radius:5px; overflow-y: scroll;
border:1px solid #CCC; height: 160px;width: 400px;float: left;}
#input { border-radius:2px; border:1px solid #ccc;
margin-top:10px; padding:5px; width:400px; }
#status { width:88px; display:block; float:left; margin-top:15px; }
.onlineList {
width: 200px;
height: 160px;
background-color: #ccc;
border: 1px solid #DDD;
margin-top: 50px;
margin-left: 420px;
}
li {
display: inline;border: 1px solid red;
}
.ul {
margin-left:auto; margin-right:auto;
width: 600px;
}
</style>
</head>
<script type="text/javascript">
//window.onbeforeunload = disConnect;
</script>
<body>
<div class="ul">
<div id="content"></div>
<div class="onlineList">
当前在线：
<div id="list">
</div>
</div>
</div>
<div class="textInput">
<span id="status">connecting</span>
<input type="text" id="input" value="只能选择右上列表上的姓名进行登录"/>
</div>
<script src="./jquery.js"></script>
<script src="./client.js"></script>
</body>
</html>
对应的client.js文件
"use strict";
// for better performance - to avoid searching in DOM
var content = $('#content');
var input = $('#input');
var statusObj = $('#status');
var userList = $("#list");
// my color assigned by the server
var myColor = false;
// my name sent to the server
var myName = false;
var connection = null;
var currentToUser = null;
connect();
window.onbeforeunload = beforeDisConnect;//监听浏览器关闭前的事件
window.onunload = disConnect;//监听浏览器关闭时
/**
* Send mesage when user presses Enter key
*/
input.keydown(function (e) {
if (e.keyCode === 13) {
var msg = $(this).val();
if (!msg) {
return;
}
if (!myName) {
myName = msg;//定义名字
statusObj.text(myName);
input.val("");
if (connection) {
connection.json.send({ logicId: "login", username: myName });
}
return;
}
var time = new Date();
var tmpTime = time.getFullYear() + "-" + ((time.getMonth() < 9 ? "0" : "") + (time.getMonth() + 1)) + "-" + ((time.getDate() < 10 ? "0" : "") + time.getDate()) + " "
+ ((time.getHours() < 10 ? "0" : "") + time.getHours()) + ":" + ((time.getMinutes() < 10 ? "0" : "") + time.getMinutes()) + ":" + ((time.getSeconds() < 10 ? "0" : "") + time.getSeconds());
// send the message as an ordinary text
msg = { "@class": "test.EntityIn", logicId: "chat", username: myName, msg: input.val(),
to:currentToUser,time:tmpTime};
//alert(typeof(object));
connection.json.send(msg);
$(this).val('');
// disable the input field to make the user wait until server
// sends back response
}
});
/**
* Add message to the chat window
*/
function addMessage(author, message, dt) {
content.prepend('<p><span>' + author + '</span> @ '+dt+ ': ' + message + '</p>');
}
function connect() {
// open connection
connection = io.connect('http://127.0.0.1:1337', { 'reconnect': false });
connection.on('connect', function (data) {
// first we want users to enter their names
input.removeAttr('disabled');
statusObj.text('登录:');
connection.send(1);
});
connection.on("error", function (error) {
// just in there were some problems with conenction...
content.html($('<p>', {
text: 'Sorry, but there\'s some problem with your '
+ 'connection or the server is down.'
}));
});
// most important part - incoming messages
connection.on("message", function (message) {
var logicId = message.logicId;
if (logicId == 'conn_success') {//连接成功
var users = message.users;
for (var i = 0; i < users.length; i++) {
userList.append('<a href="#" onclick="chatToSb(this.innerHTML)">'+users[i]+'</a></br>');
}
} else if (logicId == "chat") {
addMessage(message.from,message.msg,message.time);
}else if(logicId == "history"){
var historyMsgs = message.historyMsgs;
for(var i = 0; i < historyMsgs.length; i++){
addMessage(historyMsgs[i].from,historyMsgs[i].msg,historyMsgs[i].time);
}
}
});
}
function chatToSb(username) {
currentToUser = username;
}
function disConnect(){
connection.disconnect();
//alert("断开连接");
}
function beforeDisConnect() {
return "确认离开";
}
接下来就是重头戏的服务端了server.js
"use strict";
var http = require('http');
/**
* Global variables
*/
var history = [];
// list of currently connected clients (users)
var users = ["user1","user2"];
var clients = [];
/**
* HTTP server
*/
var server = http.createServer(function (request, response) {
// Not important for us. We're writing socket.io server, not HTTP server
});
server.listen(1337);
/**
* socketio server
*/
var io = require("socket.io").listen(server);
//io监听socket事件
io.on('connection', function (connection) {
console.log((new Date()) + ' Connection from origin ' + connection.id + '.');
var json = { logicId:"conn_success",users: users };
connection.json.send(json);
var userName = false;
console.log((new Date()) + ' Connection accepted.');
connection.on('message', function (message) {
console.log(message);
if (message.logicId == "login") {
clients[message.username] = connection; //将用户名与连接对应
connection.username = message.username;
}else if(message.logicId == "chat") {//用户发起会话
//1、查找该用户是否有历史消息
var toUser = message.to;//会话目标
var from = message.username;//会话发起人
if(history[toUser]&&history[toUser][from]){
var historyMsgs = [];
for (var i = 0; i < history[toUser][from].length; i++) {
historyMsgs.push(history[toUser][from][i]);
};
connection.json.send({logicId:"history",historyMsgs:historyMsgs});
}
//2、检查目标用户是否在线，若在线，转发用户请求,否则，存为历史会话中
var objConnect = clients[toUser];
var chatJson = {logicId:"chat", from: from, time: message.time, msg: message.msg };
connection.json.send(chatJson);
if (objConnect) {
objConnect.json.send(chatJson);
} else {//存储于历史会话中
if (!history[from]||!history[from][toUser]) {
if (!history[from]) {
history[from] = [];
}
history[from][toUser] = [];
}
history[from][toUser].push(chatJson);
}
}
});
// user disconnected
connection.on('disconnect', function (socket) {
console.log("关闭连接:" + socket);
delete clients[connection.username];//删除用户的连接
});
});
这里都假设大家是在win7的环境下，并且装了node.js，方便调试的话还可以安装node-inspector调试工具，或者用webStorm IDE，具体的可以参看我的前一篇博文，除了这三个文件当然还需要服务端和客户端的socket.io文件，node.js就是下载第三方包的方式了，客户端的socket.io文件网上可以找到的。
接下来简单介绍一下以上代码实现的功能以及用法，打开页面后首先就是登录，由于例子比较简单，并没有单独的登录页面，直接在文本框中输入用户名，注意（这里的用户名只能是user1或者user2，读者可以在server.js的users添加自己需要的用户名，这里其实是固定的），然后回车，就是登录了，然后输入需要发送的信息，并且点击接受者的用户名，否则会接收者是空的，关闭页面的时候，我们会监听页面关闭事件，给服务端发送disconnect事件，删除当前用户名的连接。根据这个流程，代码其实很简单，就不再详解了。
本来不喜欢贴源代码的，但是鉴于给大家一个实际的效果，就贴出来了，做一个参考，希望能帮到大家，也请大牛赐教。