index.js

var Express = require('express'),
    Routes = require('./routes'),
    HTTP = require('http'),
    R = require('rethinkdb'),
    Path = require('path');

var App = Express(),
    Server = HTTP.createServer(App),
    IO = require('socket.io')(Server);


// configure the App itself
App.set('port', process.env.PORT || 3000);
App.set('views', __dirname + '/views');
App.set('view engine', 'jade');
//App.use(require('serve-favicon'));
App.use(require('morgan')('combined'));
App.use(require('body-parser').urlencoded({extended: false}));
// App.use(require('method-override'));
App.use(require('cookie-parser')('a cookie secret'));
//App.use(require('express-session')('a session secret'));
// App.use(require('less-middleware')({src: __dirname + '/public'}));
App.use(Express.static(Path.join(__dirname, 'public')));
App.use(require('errorhandler')());

App.get('/', Routes.index);

var currentUsers = 0,
    currentCanvas = '';

IO.on('connection', function(user) {
    console.log("User Connected:" + user.id);

    user.on('started drawing', function(point) {
        point.userId = user.id;
        user.broadcast.emit('started drawing', point);
    });

    user.on('drawing move', function(point) {
        point.userId = user.id;
        user.broadcast.emit('drawing move', point);
    });

    user.on('ended drawing', function(canvas) {
        user.broadcast.emit('ended drawing', {userId: user.id});
        currentCanvas = canvas.image;
    });

    user.on("RESET", function() {
        console.log('User ' + user.id + 'requested a full reset');
        user.broadcast.emit("RESET");
    });

    IO.emit('userCount', {users: ++currentUsers});
    user.on('disconnect', function() {
        IO.emit('userCount', {users: --currentUsers});
    });

    user.emit('canvas load', {uri: currentCanvas});
});

Server.listen(App.get('port'), function() {
    console.log('Listening on http://localhost:' + App.get('port'))
});