sockt-io.js

const port = process.env.PORT || 3000,
    server   = require('http').createServer(),
    io       = require('socket.io').listen(server),
    crypto   = require('crypto'),
    users = {},
    socks = {},
    clients = [],
    users = [],
    oldSocket = "";

io.sockets.on('connection', (socket) => {

    socket.on('online', (data) => {
        let data = JSON.parse(data);
        //检查是否是已经登录绑定
        if(!clients[data.user]) {
            //新上线用户，需要发送用户上线提醒,需要向客户端发送新的用户列表
            users.unshift(data.user);
            for(let index in clients) {
                clients[index].emit('system',JSON.stringify({type:'online',msg:data.user,time:(new Date()).getTime()}));
                clients[index].emit('userflush',JSON.stringify({users:users}));
            }
            socket.emit('system',JSON.stringify({type:'in',msg:'',time:(new Date()).getTime()}));
            socket.emit('userflush',JSON.stringify({users:users}));
        }
        clients[data.user] = socket;
        socket.emit('userflush',JSON.stringify({users:users}));
    });
    socket.on('say', (data) => {
        //dataformat:{to:'all',from:'Nick',msg:'msg'}
        data = JSON.parse(data);
        let msgData = {
            time : (new Date()).getTime(),
            data : data
        };

        if(data.to == "all") {
            //对所有人说
            for(let index in clients) {
                clients[index].emit('say',msgData);
            }
        } else {
            //对某人说
            clients[data.to].emit('say',msgData);
            clients[data.from].emit('say',msgData);
        }
    });
    socket.on('offline', (user) => {
        console.log(user);
        socket.disconnect();
    });

    socket.on('disconnect', () => {
        //有人下线
        setTimeout(userOffline,5000);

        function userOffline() {
            for(let index in clients) {
                if(clients[index] == socket) {
                    users.splice(users.indexOf(index),1);
                    delete clients[index];
                    for(let index_inline in clients) {
                        clients[index_inline].emit('system',JSON.stringify({type:'offline',msg:index,time:(new Date()).getTime()}));
                        clients[index_inline].emit('userflush',JSON.stringify({users:users}));
                    }
                    break;
                }
            }
        }
    });
});

/********************************************************************************
 *                              Other example                                   *
 ********************************************************************************/
/**
 * Avatar config
 * @type {string}
 */
//let avatar_url = "http://cdn.libravatar.org/avatar/";
let avatar_url = "http://www.gravatar.com/avatar/";
let avatar_404 = ['mm', 'identicon', 'monsterid', 'wavatar', 'retro'];

function Uid() { this.id = ++Uid.lastid; }

Uid.lastid = 0;

/**
 * Handle users
 */
io.sockets.on('connection', function (socket) {

    // Event received by new user
    socket.on('join', function (recv, fn) {

        if (!recv.user) {
            socket.emit('custom_error', { message: 'User not found or invalid' });
            return;
        }

        // The user is already logged
        if (users[recv.user]) {
            socket.emit('custom_error', { message: 'The user '+ recv.user +' is already logged' });
            return;
        }

        // If there is users online, send the list of them
        if (Object.keys(users).length > 0)
            socket.emit('chat', JSON.stringify( { 'action': 'usrlist', 'user': users } ));

        // Set new uid
        uid = new Uid();
        socket.user = recv.user;
        my_avatar = get_avatar_url(socket.user);

        // Add the new data user
        users[socket.user] = {'uid': Uid.lastid, 'user': socket.user, 'name': recv.name, 'status': 'online', 'avatar': my_avatar}
        socks[socket.user] = {'socket': socket};

        // Send to me my own data to get my avatar for example, usefull in future for db things
        //socket.emit('chat', JSON.stringify( { 'action': 'update_settings', 'data': users[socket.user] } ));

        // Send new user is connected to everyone
        socket.broadcast.emit('chat', JSON.stringify( {'action': 'newuser', 'user': users[socket.user]} ));

        if (typeof fn !== 'undefined')
            fn(JSON.stringify( {'login': 'successful', 'my_settings': users[socket.user]} ));
    });

    // Event received when user want change his status
    socket.on('user_status', function (recv) {
        if (users[socket.user]) {
            users[socket.user].status = recv.status;
            socket.broadcast.emit('chat', JSON.stringify( {'action': 'user_status', 'user': users[socket.user]} ));
        }
    });

    // Event received when user is typing
    socket.on('user_typing', function (recv) {
        let id = socks[recv.user].socket.id;
        io.sockets.socket(id).emit('chat', JSON.stringify( {'action': 'user_typing', 'data': users[socket.user]} ));
    });

    // Event received when user send message to another
    socket.on('message', function (recv, fn) {
        let d = new Date();
        let id = socks[recv.user].socket.id;
        let msg = {'msg': recv.msg, 'user': users[socket.user]};
        if (typeof fn !== 'undefined')
            fn(JSON.stringify( {'ack': 'true', 'date': d} ));
        io.sockets.socket(id).emit('chat', JSON.stringify( {'action': 'message', 'data': msg, 'date': d} ));
    });

    // Event received when user has disconnected
    socket.on('disconnect', function () {
        if (users[socket.user]) {
            socket.broadcast.emit('chat', JSON.stringify( {'action': 'disconnect', 'user': users[socket.user]} ));
            delete users[socket.user];
            delete socks[socket.user];
        }
    });
});

/**
 * Listen to the server port
 */
server.listen(port, function () {
    let addr = server.address();
    console.log('jqchat listening on ' + addr.address + addr.port);
});

/**
 * Generate url for avatar purpose
 * @param user
 * @returns {string}
 */
function get_avatar_url(user) {
    let mymd5 = crypto.createHash('md5').update(user);
    let rand = random(0, avatar_404.length);
    let end = '?d=' + avatar_404[rand];
    return avatar_url + mymd5.digest("hex") + "/" + end
}

/**
 *
 * @param low
 * @param high
 * @returns {number}
 */
function random(low, high) {
    return Math.floor(Math.random() * (high - low) + low);
}

/**
 *
 * @returns {*}
 */
function get_diff_time() {
    if(disconnect)  {
        return connect - disconnect;
    }
    return false;
}