the-event-system.md

The event system

Outdated documentation, only applicable to 1.0.0 beta 5 and below. See api-platform#191

DunglasApiBundle leverages the Symfony Event Dispatcher Component to provide a powerful event system triggered in the object lifecycle.

Additionally to events triggered by the Symfony HTTP Kernel and by Doctrine ORM (if you use it), DunglasApiBundle comes with its own set of events occurring during the handling of the request:

Retrieving list

• api.retrieve_list (Dunglas\ApiBundle\Event\Events::RETRIEVE_LIST): occurs after the retrieving of an object list during a GET request on a collection.

Retrieving item

• api.retrieve (Dunglas\ApiBundle\Event\Events::RETRIEVE_LIST): after the retrieving of an object during a GET request on an item.

Creating item

• api.pre_create_validation (Dunglas\ApiBundle\Event\Events::PRE_CREATE_VALIDATION): occurs before the object validation during a POST request.
• api.pre_create (Dunglas\ApiBundle\Event\Events::PRE_CREATE): occurs after the object validation and before its persistence during a POST request.
• api.post_create (Dunglas\ApiBundle\Event\Events::POST_CREATE): event occurs after the object persistence during POST request.

Updating item

• api.pre_update_validation (Dunglas\ApiBundle\Event\Events::PRE_UPDATE_VALIDATION): event occurs before the object validation during a PUT request.
• api.pre_update (Dunglas\ApiBundle\Event\Events::PRE_UPDATE): occurs after the object validation and before its persistence during a PUT request.
• api.post_update (Dunglas\ApiBundle\Event\Events::POST_UPDATE): event occurs after the object persistence during a PUT request.

Deleting item

• api.pre_delete (Dunglas\ApiBundle\Event\Events::PRE_DELETE): event occurs before the object deletion during a DELETE request.
• api.post_delete (Dunglas\ApiBundle\Event\Events::POST_DELETE): occurs after the object deletion during a DELETE request.

## JSON-LD context builder

• api.jsonld.context_builder (Dunglas\ApiBundle\JsonLd\Event\Events::CONTEXT_BUILDER): occurs after the initialization of the context and lets you extend the context. Event object is an instance of Dunglas\ApiBundle\JsonLd\Event\ContextBuilderEvent.

Registering an event listener

In the following example, we register an event listener that will be called every time after the creation of an object:

<?php

// src/AppBundle/EventListener/MyEventListener.php

namespace AppBundle\EventListener;

use AppBundle\Entity\MyObject;
use Doctrine\Common\Persistence\ManagerRegistry;
use Dunglas\ApiBundle\Event\DataEvent;

class MyEventListener
{
    /**
     * @param DataEvent $event
     */
    public function onPostCreate(DataEvent $event)
    {
        $data = $event->getData();

        if ($data instanceof MyObject) {
            $resource = $event->getResource(); // Get the related instance of Dunglas\ApiBundle\Api\ResourceInterface

            // Do something awesome here
        }
    }
}

# app/config/services.yml

services:
    my_event_listener:
        class: "AppBundle\EventListener\MyEventListener"
        tags:  [ { name: "kernel.event_listener", event: "api.post_create", method: "onPostCreate" } ]

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