websocket试用

websocket
1.通过websocket协议握手
2.后续通过tcp流方式交互

这个文章可以作为一个协议简介

在PC上试用，winxp，软件包选用了WebSocket-Node，websocket协议的nodejs扩展包

安装：

* npm install -g node-gyp

* npm install websocket

* server端代码(ws_demo_server.js)

半抄半改

// http://ejohn.org/blog/ecmascript-5-strict-mode-json-and-more/
"use strict";

// Optional. You will see this name in eg. 'ps' or 'top' command
process.title = 'node-chat';

// Port where we'll run the websocket server
var webSocketsServerPort = 9000;

// websocket and http servers
var webSocketServer = require('websocket').server;
var http = require('http');

/**
 * Global variables
 */
// latest 100 messages
var history = [ ];
// list of currently connected clients (users)
var clients = [ ];

/**
 * HTTP server
 */
var server = http.createServer(function(request, response) {
    // Not important for us. We're writing WebSocket server, not HTTP server
});
server.listen(webSocketsServerPort, function() {
    console.log((new Date()) + " Server is listening on port " + webSocketsServerPort);
});

/**
 * WebSocket server
 */
var wsServer = new webSocketServer({
    // WebSocket server is tied to a HTTP server. WebSocket request is just
    // an enhanced HTTP request. For more info http://tools.ietf.org/html/rfc6455#page-6
    httpServer: server,
    autoAcceptConnections: false
});


function msg_history(userName, friend, msg){
    var history = {
        type: 'message',
        time: (new Date()).getTime(),
        msg: msg,
        user: userName,
        friend: friend,
    };
    return history;
}

function reg_user(userName, host, port) {
  // put logic here to detect whether the specified origin is allowed.
  return true;
}

// This callback function is called every time someone
// tries to connect to the WebSocket server
wsServer.on('request', function(request) {
    console.log((new Date()) + ' Connection from origin ' + request.origin + '.');

    // accept connection - you should check 'request.origin' to make sure that
    // client is connecting from your website
    // (http://en.wikipedia.org/wiki/Same_origin_policy)
    var connection = request.accept(null, request.origin); 
    // we need to know client index to remove them on 'close' event
    var index = clients.push(connection) - 1;
    var userName = false;

    console.log((new Date()) + ' Connection accepted.');

    // send back chat history
    if (history.length > 0) {
        connection.sendUTF(JSON.stringify( { type: 'history', data: history} ));
    }

    // user sent some message
    connection.on('message', function(message) {
        if (message.type === 'utf8') { // accept only text
            if (userName === false) { // first message sent by user is their name
            
                // remember user name
                var msgObj = JSON.parse(message.utf8Data);
                userName = msgObj['data']['userName'];
                console.log((new Date()) + ' User : ' + userName );

                // get random color and send it back to the user
                var msg = msg_history(userName, msgObj['data']['userFirend'], msgObj['data']['talkMsg']);
                connection.sendUTF(JSON.stringify(msg));
                
            } else { // log and broadcast the message
                console.log((new Date()) + ' Received Message from ' + userName + ': ' + message.utf8Data);

                // we want to keep history of all sent messages
                var msgObj = JSON.parse(message.utf8Data);
                var msg = msg_history(msgObj['data']['userName'], msgObj['data']['userFirend'], msgObj['data']['talkMsg']);
                history.push(msg);
                history = history.slice(-100);

                // broadcast message to all connected clients
                var json = JSON.stringify(msg);
                for (var i=0; i < clients.length; i++) {
                    clients[i].sendUTF(json);
                }
            }
        }else if (message.type === 'binary') {
            console.log('Received Binary Message of ' + message.binaryData.length + ' bytes');
            connection.sendBytes(message.binaryData);
        }else {
            console.log('Received Unknow Type Message');
            connection.sendBytes('Received Unknow Type Message');
        }
    });

    // user disconnected
    connection.on('close', function(connection) {
        if (userName !== false ) {
            console.log((new Date()) + " Peer "
                + connection.remoteAddress + " disconnected.");
            // remove user from the list of connected clients
            clients.splice(index, 1);
            // push back user's color to be reused by another user
        }
    });

});

* clien端代码(ws_demo_client.html)

(也是半抄半改，chrom下OK，测试要多开几个页面)

<html>
<head>
<script type="text/javascript">
var host = '127.0.0.1';
var port = 9000;
var url = 'ws://'+host+':'+port+'/';

var w = new WebSocket(url);

w.onopen = function(){
	$('stat-box').innerHTML = '已连接到服务器......<br/>';
}

function json2str(json){
    return JSON.stringify(json)
}

function str2json(str){
    return JSON.parse(str);
}

w.onmessage = function(e){
    var obj = str2json(e.data);
	var chatBox = $('chat-box');

    if (typeof(obj.type) == undefined) { 
        
    } else if (obj.type == 'history')  {
        for(var idx in obj.data){ 
            var time = Math.round(obj.data[idx]['time'] / 1000);
            var fromWho = obj.data[idx]['user'];
            var toWho = ( "" == obj.data[idx]['friend'] ) ? "所有人" : obj.data[idx]['friend'];
            var msg = obj.data[idx]['msg'];
            chatBox.innerHTML = chatBox.innerHTML + time + ':<br/> ' + fromWho + " 对 " + toWho + " 说：" + msg + '<br/>';
        }
    } else if (obj.type == 'message') {
        var time = Math.round(obj['time'] / 1000);
        var fromWho = obj['user'];
        var toWho = ( "" == obj['friend'] ) ? "所有人" : obj['friend'];
        var msg = obj['msg'];
        chatBox.innerHTML = chatBox.innerHTML + time + ':<br/> ' + fromWho + " 对 " + toWho + " 说：" + msg + '<br/>';
    }
}

function send(){
	var userName = $('userName');
	var userFirend = $('userFirend');
	var talkMsg = $('talkMsg');
    
    var msgToSend={"data":{"userName":userName.value,"userFirend":userFirend.value,"talkMsg":talkMsg.value}};
	w.send(json2str(msgToSend));
}
function $(id){
	return document.getElementById(id);
}
</script>
</head>

<body>
<div id="chat-box" style="bordddder:1px solid #cccccc; width:400px; height:400px; overflow:scroll;"></div>
<div id="stat-box" style="bordddder:1px solid #cccccc;"></div>
昵称    :<input type="text" id="userName"/><br/>
发给朋友:<input type="text" id="userFirend"/><br/>
内容    :<input type="text" id="talkMsg"/><br/>
<input type="button" id="send" onClick="send();" value="发送"/>
</body>
</html>