app.js

/**
 * Most of the code is found here :
 * http://naholyr.fr/2011/07/authentification-et-websocket-avec-node-js-express-et-socket-io/
 * 
 * Code exporting into other files :
 * http://stackoverflow.com/questions/6059246/how-to-include-route-handlers-in-multiple-files-in-express
 * 
 * Interesting link about socket.io and sessions :
 * http://www.danielbaulig.de/socket-ioexpress/
 * 
 * Savior link about session length :
 * http://rahulmehta1.wordpress.com/2011/11/03/login-form-in-node-js-with-session-mangement/
 */

var path = require('path');
var express = require('express');
var app = module.exports = express.createServer();
var port = process.env.PORT || 1337;
var RedisStore = require('connect-redis')(express);
var redis = require('redis');
var client = redis.createClient();
var util;

/**
 * In case an error happens with redis
 */
client.on("error", function (err) {
  console.log("error event - " + client.host + ":" + client.port + " - " + err);
});

/**
 * Configuration
 */
app.configure(function() {
  // Defines the view folder and engine used.
  this.set('views', path.join(__dirname, 'views'));
  this.set('view engine', 'ejs');
  
  // Allow parsing form data
  this.use(express.bodyParser());
  
  // Allow parsing cookies from request headers
  this.use(express.cookieParser());
  // Session management
  this.use(express.session({
    // Private crypting key
    secret: 'keyboard cat',
    store: new RedisStore,
    cookie: {
      maxAge: 1800000
    }
  }));
  this.use(app.router);
});
app.configure('development', function(){
  this.use(express.errorHandler({
    dumpExceptions: true,
    showStack: true
  }));
});
app.configure('production', function(){
  this.use(express.errorHandler());
});

/**
 * Routes
 */
require('./routes/middlewares.js')(app);
require('./routes/home.js')(app);
require('./routes/guest.js')(app, client);

/**
 * Start server
 */
if (!module.parent) {
  app.listen(port);
}

guest.js

module.exports = function(app, client) {
  /**
   * Login page - Only guests will see this page
   */
  app.get('/guest', [app.requireGuest], function (req, res, next) {
    // Render form
    res.render('guest', {
      page_language: 'fr',
      page_title: "Formulaire d'identification",
      meta_description: "Page de login de ce site de test.",
      error: null,
      message: null
    });
  });

  /**
   * Handles login post
   */
  app.post('/guest', [app.requireGuest], function (req, res, next) {
    require('bufferjs/concat');
    var username = new Buffer(req.body.username);
    var password = new Buffer(req.body.password);
    // Preparing options to render if it fails
    var options = {
      page_language: 'fr',
      page_title: "Formulaire d'identification",
      meta_description: "Page de login de ce site de test.",
      error: null,
      message: null
    };
    // If a field is missing, render the login form
    if (!username || !password) {
      options.error = "All fields are required.";
      res.render('guest', options);
    }
    // Now, check if the user he entered exists
    client.sismember(['users', Buffer.concat(new Buffer('user:'), username)], function(err, reply) {
      if (err) {
        options.error = err;
        res.render('guest', options);
        // Cleanly close Redis' connection
        client.end();
      }
      if (reply) {
        // If he does, check if the password matches
        client.hget([Buffer.concat(new Buffer('user:'), username), 'password'], function(err, reply) {
          if (err) {
            options.error = err;
            res.render('guest', options);
            // Cleanly close Redis' connection
            client.end();
          }
          if (reply === password.toString()) {
            // If the password matches, add the session and redirects to home
            req.session.username = username.toString();
            console.log(req.session);
            res.redirect('/home');
            // Cleanly close Redis' connection
            client.end();
          }
          else {
            options.error = "Password do not match.";
            res.render('guest', options);
            // Cleanly close Redis' connection
            client.end();
          }
        });
      }
      else {
        options.error = "Username does not exist.";
        res.render('guest', options);
        // Cleanly close Redis' connection
        client.end();
      }
    });
  });
}

home.js

module.exports = function(app) {
  /*
   * Home page for non-guests
   */
  app.get('/', [app.requireLogin], function (req, res, next) {
    res.redirect('/home', 301);
  });
  
  /**
   * Home page for non-guests
   */
  app.get('/home', [app.requireLogin], function(req, res, next) {
    res.render('home', {
      page_language: 'fr',
      page_title: "Page d'accueil",
      meta_description: "Page d'accueil de ce site de test.",
      error: null,
      message: null
    });
  });
}

middlewares.js

module.exports = function(app) {
  /**
   * Middleware for limited access
   */
  app.requireLogin = function(req, res, next) {
    console.log(req.session);
    if (req.session.username) {
      // User is authenticated, let him in
      next();
    }
    else {
      // Otherwise, we redirect him to login form
      res.redirect('/guest');
    }
  }

  /**
   * Middleware for limited access
   */
  app.requireGuest = function(req, res, next) {
    if (req.session.username) {
      // If the user is authenticated, redirect him to the home page
      res.redirect('/home');
    }
    else {
      // Otherwise, let him in
      next();
    }
  }
}