express/examples/mvc/controllers/user.js

// Fake user database for example

var users = [
    { id: 0, name: 'TJ', email: 'tj@vision-media.ca' }
  , { id: 1, name: 'Simon', email: 'simon@vision-media.ca' }
];

function get(id, fn) {
  if (users[id]) {
    fn(null, users[id]);
  } else {
    fn(new Error('User ' + id + ' does not exist'));
  }
}

module.exports = {
  
  // /users
  
  index: function(req, res){
    res.render(users);
  },

  // /users/:id

  show: function(req, res, next){
    get(req.params.id, function(err, user){
      if (err) return next(err);
      res.render(user);
    });
  },
  
  // /users/:id/edit
  
  edit: function(req, res, next){
    get(req.params.id, function(err, user){
      if (err) return next(err);
      res.render(user);
    });
  },
  
  // PUT /users/:id
  
  update: function(req, res, next){
    var id = req.params.id;
    get(id, function(err){
      if (err) return next(err);
      var user = users[id] = req.body.user;
      user.id = id;
      req.flash('info', 'Successfully updated _' + user.name + '_.');
      res.redirect('back');
    });
  }
};