code: public function IndexAction()
    {
      // Checks if the user is connected
      if (Session::islogged())
      {
        // Checks if the user is the administrator
        if (Session::userEmail() == User::adminEmail())
        {
          // Reads all articles, users & comments, then stores them
          $allArticles  = ModelFactory::get('Article')->list();
          $allComments  = ModelFactory::get('Comment')->list();
          $allUsers     = ModelFactory::get('User')   ->list();
  
          // Returns the rendering of the view admin with the user datas
          return $this->render('admin/admin.twig', [
            'allArticles'       => $allArticles,
            'allComments'       => $allComments,
            'allUsers'          => $allUsers
          ]);
        }
        else {
          // Creates a warning message to inform that only the admin can access to this page
          htmlspecialchars(Session::createAlert('Access reserved for the site administrator', 'warning'));
  
          // Redirects to the view home
          $this->redirect('home');
        }
      }
      else {
        // Creates a cancel message to ask to be connected
        htmlspecialchars(Session::createAlert('You must be logged in to access the administration', 'cancel'));
  
        // Redirects to the view loginUser
        $this->redirect('user!login');
      }
    }
docs: *********************************************************************\
  Reads all objects for CRUD actions from the database, then display them
  @return mixed => the rendering of the view admin