express_is_authenticated.js

// User requests the /app/ route -> Check if he is authenticated
router.get('/app/', isAuthenticated, (req, res) => res.render('app') );

// The isAuthenticated function is using passport.js here to see if the user is logged in (req.isAuthenticated)
// It that's not the case, we redirect them to the login route.
const isAuthenticated = (req, res, next) => {
  if(req.isAuthenticated())  return next();
  res.redirect('/login');
}