Reading from nested doc in mongoose nodejs

app.get('/code/:id', function(req, res){

    if (req.user) {
      var username = req.user.username;
    }

    //if (app.requireAuth === true && req.loggedIn === false)
      //res.redirect('/auth/twitter');

    //get the example
    models.codes.findById(req.params.id, function(err, data){
      if (data) {
        models.users.findOne({name: username}, function(err, userdata){
         //render the view page
         res.render('code.jade', {
             locals: {
               title: data.title,
               page: '',
               code: data,
               user: username,
               userdata: userdata
             }
         });
        });
      } else {
        res.redirect('/404');
      }

    });
  });