server.js

var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var http = require('http');
var routes = require('./routes/index');
var users = require('./routes/users');
var PORT = 8080;
var app = express();
app.locals.title = '聊天室';
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);
app.use('/users', users);

// -- socket.io  start
var server = http.Server(app);
var io = require('socket.io').listen(server);
var roomUser = {};
io.on('connection', function (socket) {

    // 获取用户当前的url，从而截取出房间id
    var url = socket.request.headers.referer;
    var split_arr = url.split('/');
    var roomid = split_arr[split_arr.length-1] || 'index';
    var user = '';

    socket.on('join', function (username) {
         user = username;
        // 将用户归类到房间
        if (!roomUser[roomid]) {
            roomUser[roomid] = [];
        }
        roomUser[roomid].push(user);
        socket.join(roomid);
        socket.to(roomid).emit('sys', user + '加入了房间');
        socket.emit('sys',user + '加入了房间');
    });

    // 监听来自客户端的消息
    socket.on('message', function (msg) {
        // 验证如果用户不在房间内则不给发送
        if (roomUser[roomid].indexOf(user)< 0) {  
          return false;
        }
        socket.to(roomid).emit('new message', msg,user);
        socket.emit('new message', msg,user);
    });

    // 关闭
    socket.on('disconnect', function () {
        // 从房间名单中移除
        socket.leave(roomid, function (err) {
            if (err) {
                log.error(err);
            } else {
                var index = roomUser[roomid].indexOf(user);
                if (index !== -1) {
                    roomUser[roomid].splice(index, 1);
                    socket.to(roomid).emit('sys',user+'退出了房间');
                } 
            }
        });
    });
});
// -- socket.io end
// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});

if (!module.parent) {
    // This server is socket server
    server.listen(PORT);
    console.log('chatroom started up on port '+PORT);
}
module.exports = server;