Update another field on slug creation using DoctrineExtensios - symfony

Question

I'm using DoctrineExtensions in my Symfony 2 project, i have a simple Entity class where i'm using Sluggable on a property, then i would like to set the value to another property based on the slug, but, even when using Lifecycle Callbacks #ORM\PrePersist, #ORM\PreFlush, at this time the slug property still empty, meaning no slug is generated yet, here is my class, to keep this short, i'm not going to put here the get and set function of each property, just the part of the class that are important for this example(please, read the comments)
<?php
namespace My\LearnBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;
use Gedmo\Mapping\Annotation as Gedmo;
/**
* Banner
*
* #ORM\Table(name="banner")
* #ORM\HasLifecycleCallbacks()
*/
class Banner {
/**
* #var integer
*
* #ORM\Column(name="id", type="bigint", nullable=false)
* #ORM\Id
* #ORM\GeneratedValue(strategy="IDENTITY")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="name", type="string", length=128, nullable=false)
* #Assert\NotBlank()
*/
private $name;
/**
* #var string
*
* #ORM\Column(name="slug", type="string", length=256, nullable=false)
* #Gedmo\Slug(fields={"name"})
*/
private $slug;
/**
* #var string
*
* #ORM\Column(name="tracking_url", type="string", length=256, nullable=false)
*/
private $trackingUrl;
/**
* Set slug
*
* #param string $slug
* #return Banner
*/
public function setSlug($slug) {
$this->slug = $slug;
$this->trackingUrl = $slug."/tracking"; //Doesn't work
return $this;
}
/**
* Set trackingUrl value
*
* #ORM\PreUpdate
*/
public function setTrackingUrlValue() {
//the slug is empty. Doesn't work
$this->trackingUrl = $this->slug."/tracking";
return $this;
}
/**
* Set trackingUrl value
*
* #ORM\PreFlush
*/
public function setTrackingUrlValueOnFlush() {
//the slug is empty. Doesn't work
return $this->setTrackingUrlValue();
}
}
What i've tried? well, using the setSlug function but it doesn't work(note comments on example above), seems it is not called. Using Lifecycle Callbacks #ORM\PrePersist, #ORM\PreFlush and #ORM\PreUpdate, doesn't work neither.
Now i solved this in the controller, after calling flush on the EntityManager, setting the property value based on the slug and calling flush again, so, making 2 database query in a single request, one for insert, one for update. I don't want to use an Event Listener because this behavior is just for this particular entity, or exist a way to attach an event listener to a single entity?.
But right now, i would like to know:
why what i was trying to do using Lifecycle Callbacks didn' work?
Why using the setSlug function didn't work?
A cleaner way to accomplish what i want?
thanks

Answer 1

What's probably happening is that the annotated listeners have a higher priority than the one creating the slug (or they have an equal priority in which case the annotated ones get probably added before).
I'm afraid you have to ditch annotations, create an actual listener and tag it for the event registration compiler pass to pick it up. What's nasty with this one is that the bundle seems to use onFlush for creating the slug (code).
Listener
namespace Acme\DemoBundle\Listener;
use Acme\DemoBundle\Model\TrackingUrlUpdateable;
use Doctrine\ORM\Event\OnFlushEventArgs;
class TrackingUrlUpdater
{
public function onFlush(OnFlushEventArgs $eventArgs)
{
$em = $eventArgs->getEntityManager();
$uof = $em->getUnitOfWork();
// Let's process both types of entities in a single loop.
$entities = array_merge(
$uof->getScheduledEntityInsertions(),
$uof->getScheduledEntityUpdates()
);
foreach ($entities as $entity) {
// Using a fictional interface (e.g. for making testing easier).
if (!($entity instanceof TrackingUrlUpdateable)) {
continue;
}
// `Banner::updateTrackingUrl()` would internally change the
// tracking url to the correct one.
$entity->updateTrackingUrl();
// The change-set must be recomputed as its fields were modified
// in the previous step.
$uof->recomputeSingleEntityChangeSet(
$em->getClassMetadata(get_class($entity)),
$entity
);
}
}
}
Registration
What's left now is to register the listener with a lower priority than the Sluggable listener.
<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:doctrine="http://symfony.com/schema/dic/doctrine">
<services>
<service id="acme.listener.tracking_url" class="Acme\DemoBundle\Listener\TrackingUrlUpdater">
<tag name="doctrine.event_listener" event="onFlush" priority="-1" />
</service>
</services>
</container>
Oh, and don't forget to test!

Answer 2

Assuming you're using StofDoctrineExtensionsBundle to integrate the library, the alternative would be to increase the priority of the sluggable listener so that your annotated callbacks would get invoked after the sluggable listener.
A compiler pass would probably do the trick.
namespace Acme\DemoBundle\DependencyInjection\CompilerPass;
use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
use Symfony\Component\DependencyInjection\ContainerBuilder;
class SluggableListenerPriorityChangingPass implements CompilerPassInterface
{
public function process(ContainerBuilder $container)
{
$id = 'stof_doctrine_extensions.listener.sluggable';
$tag = 'doctrine.event_subscriber';
$definition = $container->getDefintion($id);
$attributes = $definition->getTag($tag);
if (!$attributes) {
throw new \LogicException("The listener (`$id`) must have a `$tag` tag.");
}
$attributes['priority'] = 10;
$definition
->clearTag($tag);
->addTag($tag, $attributes)
;
}
}
The sluggable listener service itself is registered here, if its enabled from the configuration.