chat-room.js

var express = require('express');
var app = express();
var http = require('http').Server(app);
var io = require('socket.io')(http, {path: '/node/socket.io'});
var messageLog = [];
var clients = [];

io.on('connection', function(socket) {
    if (messageLog.length > 50) {
        messageLog.shift();
    }

    socket.on('join', function (name) {
        socket.name = name;
        clients.push(name);

        io.emit('message log', messageLog);
        console.log(socket.name + ' joined the chat.');
    });

    socket.on('user connected', function(user) {
        var response = {
            connected: user + ' has connected.',
            clients: clients
        };

        var message = {
            user: user,
            message: ' has connected.'
        };

        io.emit('user connected', response);
        messageLog.push(message);
    });

    socket.on('typing', function(user) {
        var message = user  + ' is currently typing...';

        socket.broadcast.emit('typing', message);
    });

    socket.on('chat message', function(message) {
        if (messageLog.length > 50) {
            messageLog.shift();
        }

        io.emit('chat message', message);
        messageLog.push(message);
    });

    socket.on('disconnect', function() {
        clients.splice(clients.indexOf(socket.name), 1);

        var response = {
            user: socket.name,
            clients: clients
        };

        var message = {
            user: socket.name,
            message: ' has disconnected.'
        };

        io.emit('disconnect', response);
        messageLog.push(message);
        console.log(socket.name + ' disconnected from the chat.');
    });
});

http.listen(3000);