Install flashMessage from AuthenticationHandler in Symfony2

I have a problem with FOSUserBundle since I login with bad credentials. I am getting the full stack as an error message:

Mistake! 'Symfony \ Component \ Security \ Core \ Exception \ BadCredentialsException' with "Bad Credentials" message in / var / www / html / vendor / symfony / symfony / src / Symfony / Component / Security / Core / Authentication / Provider / UserAuthenticationProvider .php: 90

And this is ugly to me, so very ugly for users. So I am thinking of two solutions: go to the AJAX login that I am working on but it doesn’t work, or I am doing something wrong (explain below) and found a way to change this ugly message (I didn’t get this yet another one, so any advice will be helpful).

Now about the first solution, this is what I did:

• Implements AuthenticationHandler
  
  :

  <?php
  
  namespace UsuarioBundle\Handler;
  
  use Symfony\Component\HttpFoundation\Response;
  use Symfony\Component\HttpFoundation\RedirectResponse;
  use Symfony\Bundle\FrameworkBundle\Routing\Router;
  use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
  use Symfony\Component\HttpFoundation\Request;
  use Symfony\Component\Security\Http\Authentication\AuthenticationSuccessHandlerInterface;
  use Symfony\Component\Security\Http\Authentication\AuthenticationFailureHandlerInterface;
  use Symfony\Component\Security\Core\Exception\AuthenticationException;
  
  class AuthenticationHandler
      implements AuthenticationSuccessHandlerInterface,
      AuthenticationFailureHandlerInterface
  {
      private $router;
  
      public function __construct(Router $router)
      {
          $this->router = $router;
      }
  
      public function onAuthenticationSuccess(Request $request, TokenInterface $token)
      {
          if ($request->isXmlHttpRequest()) {
              // do I need something here?
          } else {
              // If the user tried to access a protected resource and was forces to login
              // redirect him back to that resource
              if ($targetPath = $request->getSession()->get('_security.target_path')) {
                  $url = $targetPath;
              } else {
                  // Otherwise, redirect him to wherever you want
                  $url = $this->router->generate('user_view', array('nickname' => $token->getUser()->getNickname()));
              }
  
              return new RedirectResponse($url);
          }
      }
  
      public function onAuthenticationFailure(Request $request, AuthenticationException $exception)
      {
          if ($request->isXmlHttpRequest()) {
              // Handle XHR here
          } else {
              // Create a flash message with the authentication error message
              $request->getSession()->setFlash('error', $exception->getMessage());
              $url = $this->router->generate('user_login');
  
              return new RedirectResponse($url);
          }
      }
  }
  
        
  
          
          
          
        
  
      

• Define a service and register a handler:

  parameters:
      vendor_security.authentication_handler: UsuarioBundle\Handler\AuthenticationHandler
  
  services:
      authentication_handler:
          class:  %vendor_security.authentication_handler%
          arguments:  [@router]
          tags:
              - { name: 'monolog.logger', channel: 'security' }
  
        
  
          
          
          
        
  
      

• Change the links to security.yml
  
  :

  firewalls: master: sample: ^ / form_login: provider: fos_userbundle csrf_provider: form.csrf_provider login_path: / login check_path: / login_check success_handler: authentication_handler fail_handler: authentication_handler

        logout:
             path: fos_user_security_logout
             target: /
             invalidate_session: false
        anonymous: ~
  
        
  
          
          
          
        
  
      

But I am getting this error when I try to login with invalid credentials:

Attempting to call the setFlash method in the "Symfony \ Component \ HttpFoundation \ Session \ Session" class in /var/www/html/src/UsuarioBundle/Handler/AuthenticationHandler.php line 52.

Why? I am testing the method getSession()

and the part HttpFoundation

that I include in the instructions use

, so what am I doing wrong here?

Note. I am taking the code mostly from this , so I still have some doubts for this.