Doctrine2 Event Listener

config.yml

services:
   MyEventListener:
      class: My\Bundle\Listener\MyEventListener 
      tags:
        - { name: doctrine.event_listener, event: onFlush, method: onFlush }

MyEventListener.php

<?php

namespace My\Bundle\Listener;

use Doctrine\Common\EventSubscriber;
use Doctrine\ORM\Events;
use Doctrine\ORM\Event\OnFlushEventArgs;
use Doctrine\ORM\Mapping\ClassMetadata;

use My\Bundle\Entity\Event;

class MyEventListener {
	private $em = null;
	private $uow = null;
	private $attachedEvents;
	
	public function onFlush(OnFlushEventArgs $args) {

		$this -> em = $args -> getEntityManager();
		$eventManager = $this -> em -> getEventManager();

		// Remove event, if we call $this->em->flush() now there is no infinite recursion loop!
		$eventManager -> removeEventListener('onFlush', $this);

		$this -> uow = $this -> em -> getUnitOfWork();

		//Iterate through Insertions:
		foreach ($this->uow->getScheduledEntityInsertions() as $entity) {

			//Get the plain ClassName without Namespace
			$className = join('', array_slice(explode('\\', get_class($entity)), -1));
			$meta = $this -> em -> getClassMetadata(get_class($entity));

			$value = $meta -> getReflectionProperty('myEntityFieldName') -> getValue($entity);
			
			//... create your Entity...
			$newEvent = new Event;
			$newEvent->setName('...');
			//...
			
			$this -> em -> persist($newEvent);
			$this -> em -> flush();
			
			}

			// recalculate changeset, since we might messed up the relations
			$this -> em -> getUnitOfWork() -> recomputeSingleEntityChangeSet($meta, $entity);
		}


		//We can also iterate through planned deletions
		foreach ($this->uow->getScheduledEntityDeletions() AS $entity) {
			$className = join('', array_slice(explode('\\', get_class($entity)), -1));
			
			//Search for old dependencies and delete them too...
			
			$events = $this -> em -> getRepository('MyBundle:Event') -> findBy('myProperty'=>'value');
					foreach ($events as $entity) {
						$this -> em -> remove($entity);
					}
				}
			}
			$this -> em -> flush();
		}

		//Or even react on updates:
		foreach ($this->uow->getScheduledEntityUpdates() as $key => $entity) {
			$className = join('', array_slice(explode('\\', get_class($entity)), -1));
			$meta = $this -> em -> getClassMetadata(get_class($className));
			//ChangeSet is an array of key - array pairs.
			//$changeSet['fieldname'] => array(0 => 'oldValue', 1 => 'newValue')
			//if the target Value is i.e. a date, the indices 0 and 1 are i.e. DateTime Objects
			$changeSet = $this -> uow -> getEntityChangeSet($entity);

			//You can modify your Entities based on the Changes here..
			//After Persisting: 
			
			$this->uow->computeChangeSet($meta, $entity)
			}
		}
		
		//Re-attach since we're done
		$eventManager -> addEventListener('onFlush', $this);
	}

}