How to get Container object from LifecycleEventArg

问题:

I'm trying to inject the Container object (which is available in controllers) into an Entity using postLoad lifecycleCallbacks. The argument to the postLoad method is LifecycleEventArgs. I could see the container property (which I want to retrieve) in EventManager of LifecycleEventArgs according to the dump output, but it seems to be a private property and there is no getContainer() method in EventManager. The below is my code.

service.yml

services:
    ibw.jobeet.entity.job.container_aware:
        class: Ibw\JobeetBundle\Entity\Job
        tags:
            - { name: doctrine.event_listener, event: postLoad }

Ibw\JobeetBundle\Entity\Job.php

<?php
namespace Ibw\JobeetBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Doctrine\ORM\Event\LifecycleEventArgs;
use Symfony\Component\Validator\Constraints as Assert;
use Symfony\Component\HttpFoundation\File\UploadedFile;
use Symfony\Component\DependencyInjection\ContainerAware;
use Symfony\Component\DependencyInjection\ContainerInterface;

use Ibw\JobeetBundle\Utils\Jobeet;

/**
 * Job
 */
class Job
{
    //....
    /**
     * @var Container
     */
    protected $container;

    public function postLoad(LifecycleEventArgs $eventArgs)
    {
        $entity = $eventArgs->getEntity();
        $entityManager = $eventArgs->getEntityManager();
        $eventManager = $entityManager->getEventManager();
        echo '<pre>';
        \Doctrine\Common\Util\Debug::dump($eventManager, 3);

        // want to get $eventManager->container here

        exit;
    }
    //....
}

Is there any other way to retrieve it?

回答1:

You can use setter-injection which result in a call to a predefined method (setContainer() in this case) with the container as an argument upon creation of the listener service:

services:
    ibw.jobeet.entity.job.container_aware:
        class: Your\Bundle\Doctrine\Event\Listener\JobListener
        calls:
            - [setContainer, ["@service_container"]]
        tags:
            - { name: doctrine.event_listener, event: postLoad }

Now the container is injected into the constructor of your listener class:

namespace Your\Bundle\Doctrine\Event\Listener;

use Symfony\Component\DependencyInjection\ContainerInterface;
use Doctrine\ORM\Event\LifecycleEventArgs;

class JobListener
{
     /** @var ContainerInterface */
     protected $container;

     /** 
      * @param ContainerInterface @container
      */
     public function setContainer(ContainerInterface $container)
     {
          $this->container = $container;
     }

     public function postLoad(LifecycleEventArgs $eventArgs)
     {
         $entity = $eventArgs->getEntity();
         // do something with your entity here i.e.
         $entity->setFoo($this->container->getParameter('foo'));

This is just an example. Please consider injecting only the services you really need - instead of injecting the container itself. You will be rewarded with better testability and performance.