Symfony2 AJAX Login

Question

I have an example where I am trying to create an AJAX login using Symfony2 and FOSUserBundle. I am setting my own success_handler and failure_handler under form_login in my security.yml file.

Here is the class:

class AjaxAuthenticationListener implements AuthenticationSuccessHandlerInterface, AuthenticationFailureHandlerInterface
{  
    /**
     * This is called when an interactive authentication attempt succeeds. This
     * is called by authentication listeners inheriting from
     * AbstractAuthenticationListener.
     *
     * @see \Symfony\Component\Security\Http\Firewall\AbstractAuthenticationListener
     * @param Request        $request
     * @param TokenInterface $token
     * @return Response the response to return
     */
    public function onAuthenticationSuccess(Request $request, TokenInterface $token)
    {
        if ($request->isXmlHttpRequest()) {
            $result = array('success' => true);
            $response = new Response(json_encode($result));
            $response->headers->set('Content-Type', 'application/json');
            return $response;
        }
    }

    /**
     * This is called when an interactive authentication attempt fails. This is
     * called by authentication listeners inheriting from
     * AbstractAuthenticationListener.
     *
     * @param Request                 $request
     * @param AuthenticationException $exception    
     * @return Response the response to return
     */
    public function onAuthenticationFailure(Request $request, AuthenticationException $exception)
    {
        if ($request->isXmlHttpRequest()) {
            $result = array('success' => false, 'message' => $exception->getMessage());
            $response = new Response(json_encode($result));
            $response->headers->set('Content-Type', 'application/json');
            return $response;
        }
    }
}

This works great for handling both successful and failed AJAX login attempts. However, when enabled - I am unable to login via the standard form POST method (non-AJAX). I receive the following error:

Catchable Fatal Error: Argument 1 passed to Symfony\Component\HttpKernel\Event\GetResponseEvent::setResponse() must be an instance of Symfony\Component\HttpFoundation\Response, null given

I'd like for my onAuthenticationSuccess and onAuthenticationFailure overrides to only be executed for XmlHttpRequests (AJAX requests) and to simply hand the execution back to the original handler if not.

Is there a way to do this?

TL;DR I want AJAX requested login attempts to return a JSON response for success and failure but I want it to not affect standard login via form POST.

Answer 1

David's answer is good, but it's lacking a little detail for newbs - so this is to fill in the blanks.

In addition to creating the AuthenticationHandler you'll need to set it up as a service using the service configuration in the bundle where you created the handler. The default bundle generation creates an xml file, but I prefer yml. Here's an example services.yml file:

#src/Vendor/BundleName/Resources/config/services.yml

parameters:
    vendor_security.authentication_handler: Vendor\BundleName\Handler\AuthenticationHandler

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

You'd need to modify the DependencyInjection bundle extension to use yml instead of xml like so:

#src/Vendor/BundleName/DependencyInjection/BundleExtension.php

$loader = new Loader\YamlFileLoader($container, new FileLocator(__DIR__.'/../Resources/config'));
$loader->load('services.yml');

Then in your app's security configuration you set up the references to the authentication_handler service you just defined:

# app/config/security.yml

security:
    firewalls:
        secured_area:
            pattern:    ^/
            anonymous: ~
            form_login:
                login_path:  /login
                check_path:  /login_check
                success_handler: authentication_handler
                failure_handler: authentication_handler