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Events

Events

WARNING: You are browsing the documentation for EasyAdmin 3.x, which has just been released. Switch to EasyAdmin 2.x docs if your application has not been upgraded to EasyAdmin 3 yet.

EasyAdmin triggers several Symfony events during the execution of its requests, so you can listen to those events and run your own logic.

Events were useful in EasyAdmin versions previous to 3.0, because backends were defined with YAML config files instead of PHP code. Starting from EasyAdmin 3.0 everything is defined with PHP. That’s why it’s easier to customize backend behavior overloading PHP classes and methods and calling to your own services. However, the events still remain in case you want to use them.

All events are triggered using objects instead of event names defined as strings (as recommended since Symfony 4.3). They are defined under the EasyCorp\Bundle\EasyAdminBundle\Event\ namespace:

  • Events related to Doctrine entities:
    • AfterEntityBuiltEvent
    • AfterEntityDeletedEvent
    • AfterEntityPersistedEvent
    • AfterEntityUpdatedEvent
    • BeforeEntityDeletedEvent
    • BeforeEntityPersistedEvent
    • BeforeEntityUpdatedEvent
  • Events related to resource admins:
    • BeforeCrudActionEvent
    • AfterCrudActionEvent

Event Subscriber Example

The following example shows how to use an event subscriber to set the slug property of the BlogPost entity before persisting it:

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# src/EventSubscriber/EasyAdminSubscriber.php
namespace App\EventSubscriber;

use App\Entity\BlogPost;
use EasyCorp\Bundle\EasyAdminBundle\Event\BeforeEntityPersistedEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class EasyAdminSubscriber implements EventSubscriberInterface
{
    private $slugger;

    public function __construct($slugger)
    {
        $this->slugger = $slugger;
    }

    public static function getSubscribedEvents()
    {
        return [
            BeforeEntityPersistedEvent::class => ['setBlogPostSlug'],
        ];
    }

    public function setBlogPostSlug(BeforeEntityPersistedEvent $event)
    {
        $entity = $event->getEntityInstance();

        if (!($entity instanceof BlogPost)) {
            return;
        }

        $slug = $this->slugger->slugify($entity->getTitle());
        $entity->setSlug($slug);
    }
}

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.