Symfony : EventSubscriber. trigger a 404 page when a route require user must be authenticated (depending of the .env var)

Question

In my project, I create some controllers and some routes.

I added to some controller and some specific route this condition "@IsGranted("IS_AUTHENTICATED_FULLY")" like this :

Depending of the env variable, I want to disable routes who need to be authentificated (disable = redirect automatically to a 404 page). My question :

From a EventSubscriber, how can I check if the current route need an anthentificated user ?

Answer 1

You can use the kernel.exception event to get notified of a 403 / Forbidden exception that Symfony will automatically throw in this situation. In the event handler you can override the response and replace it with a RedirectResponse:

<?php

namespace App;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpKernel\Event\ExceptionEvent;
use Symfony\Component\HttpKernel\KernelEvents;

class ControllerListener implements EventSubscriberInterface
{
    public static function getSubscribedEvents()
    {
        return [
            KernelEvents::EXCEPTION => 'onException',
        ];
    }

    public function onException(ExceptionEvent $event)
    {
        // implement custom logic and set your response, eg.:
        // $event->setResponse(new RedirectResponse(...))
    }
}

Another way is to override the framework.error_controller configuration and implementing a custom controller. Within the configured controller action you can the also return a RedirectResponse.

# config/packages/framework.yaml
framework:
    error_controller: App\Controller\ErrorController::show