Barcelona Startup Map

bcnstartupmap started as an introduction to node.js session. It demonstrated how to set up a simple Express 3 node.js app with a few libraries, GET, POST and an AJAX request. A CouchDB is required to run the demo.

CouchDB view: startups/view

function(doc) {
  if(doc.jsonType == 'startup') {
    emit(doc.name, doc);
  }
}

Integrating authentication with passport.js

Setup

hash = function (pass, salt) {
  var h = crypto.createHash('sha512');
  h.update(pass);
  h.update(salt);
  return h.digest('base64');
};

app.response.message = function(type, msg){
  // reference req.session via the this.req reference
  var sess = this.req.session;
  // simply add the msg to an array for later
  sess.messages = sess.messages || [];
  sess.messages.push(msg);
  return this;
};

passport.use(new LocalStrategy(
  function(username, password, done) {
    process.nextTick(function () {
      routes.findByUsername(username, function(err, user) {
        if (err) { return done(err); }
        if (!user) { return done(null, false, { message: 'Unknown user ' + username }); }
        if (user.password != hash(password, username)) { return done(null, false, { message: 'Invalid password' }); }
        return done(null, user);
      })
    });
  }
));

passport.serializeUser(function(user, done) {
  console.log('serialize', user);
  done(null, user.username);
});

passport.deserializeUser(function(username, done) {
  console.log('deserialize', username);
  routes.findByUsername(username, function (err, user) {
    done(err, user);
  });
});

Add messages middleware

app.use(function(req, res, next) {
  if(req.isAuthenticated()) {
    res.locals.user = req.user;
  }
  var msgs = req.session.messages || [];
  res.locals({
    messages: msgs,
    hasMessages: !! msgs.length
  });
  req.session.messages = [];
  next();
});

Add this below express.session

app.use(passport.initialize());
app.use(passport.session());

Add routes

app.get('/login', routes.login);
app.get('/logout', function(req, res) { req.logOut(); res.redirect('/'); });
app.get('/signup', routes.signup);
app.post('/signup', routes.register);
app.post('/login',
  passport.authenticate('local', { successRedirect: '/',
                                   failureRedirect: '/login',
                                   failureFlash: true })
);

Add authentication middleware

function ensureAuthenticated(req, res, next) {
  if (req.isAuthenticated()) { return next(); }
  res.redirect('/login')
}

Create login.html view

<form action="/login" method="post">
    <div>
    <label>Username:</label>
    <input type="text" name="username"/><br/>
    </div><div>
    <label>Password:</label>
    <input type="password" name="password"/>
    </div><div>
    <input type="submit" value="Log In"/>
    </div>
</form>
<a href="/signup">No account? Sign up.</a>

Create signup.html

<form action="/signup" method="post">
    <div>
    <label>Username:</label>
    <input type="text" name="username"/><br/>
    </div><div>
    <label>Password:</label>
    <input type="password" name="password"/>
    </div><div>
    <input type="submit" value="Sign up"/>
    </div>
</form>
<a href="/login">Already registered? Login.</a>

Modify layout.html

<% if (hasMessages) { %>
  <ul id="messages">
    <% messages.forEach(function(msg){ %>
      <li class="<%= msg.type %>"><%= msg.msg %></li>
    <% }) %>
  </ul>
<% } %>

Encrypt passwords

var crypto = require('crypto');

hash = function (pass, salt) {
  var h = crypto.createHash('sha512');

  h.update(pass);
  h.update(salt);

  return h.digest('base64');
};

Route functions

exports.login = function(req, res) {
  res.render('login');
}

exports.findByUsername = function(username, callback) {
  db.get('user:'+username, function(error, result) {
    callback(null, result);
  });
}

exports.signup = function(req, res) {
  res.render('signup');
}

exports.register = function(req, res) {
  var user = {
    jsonType: 'user',
    username: req.body.username,
    password: hash(req.body.password, req.body.username),
    created_at: new Date(),
    updated_at: new Date()
  };
  db.insert(user, 'user:'+user.username, function(error, result) {
    console.log(error, result);
    req.logIn(user, function(error) {
      console.log(error);
      res.redirect('/');
    });
  });
}

Future Development

Please feel free to fork and contribute to this project so we can generate a full map of startups in Barcelona on a production-ready node.js service.

Services

The demo uses a CouchDB provided by iriscouch and MapBox for map services.