Check if user is logged in Express otherwise redirect to /login

backTo.js

// Get the 'backTo' value or '/' instead
var getBackTo = function (req) {
  var backTo = req.session.backTo || '/';
  delete req.session.backTo;
  return backTo;
};

getUser.js

// If user is not present stop
var getUser = function (req) {
  var user = req.session.user;

  if (user == null) {
    throw('Error');
  } else {
    return user;
  }
};

getUserOrLogin.js

// If user is not present redirect to login page
var getUserOrLogin = function (req, res, next) {
  var user = req.session.user;

  if (user == null) {
    req.session.backTo = req.originalUrl; 
    res.redirect('/login');
  } else {
    req.user = user;
    next();
  }
};

Messages.js

// Set an error message and redirect
var redirectWithMessage = function (message, url, req, res) {
  req.session.messages = message;
  res.redirect(url);
};

// Return 'messages' value or null instead
var getMessages = function (req) {
  var messages = req.session.messages || null;
  delete req.session.messages;
  return messages;
};

// Set an error message and redirect
var redirectWithError = function (error, url, req, res) {
  req.session.errors = error;
  res.redirect(url);
};

// Return 'errors' value or null instead
var getErrors = function (req) {
  var errors = req.session.errors || null;
  delete req.session.errors;
  return errors;
};