Slug solution for a DDD entity [closed] - php

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I consider a slug property not being a part of my domain model. It's just a nice convenience for the view layer.
But still: I don't want to calculate it each time I retrieve it to the view.
So I decide to only define a private property with a getter on entities which eventually will be retrieved via an URL - through a Sluggable contract. The constructor doesn't touch it all. I delegate the slug's creation to an Infrastructure Service. The ORM deals with entities using reflections, so my solution kind of looks like how Doctrine would touch those.
I register the event lifecycle listener as a Symfony service.
<?php
namespace App\Common\Domain\Model;
interface Sluggable
{
public function slug();
}
<?php
namespace IMS\Registry\Domain\Model\Manufacturer;
use App\Common\Domain\Model\Sluggable;
class Manufacturer implements Sluggable
{
private ManufacturerId $id;
private ManufacturerName $name;
private string $slug;
public function __construct(ManufacturerId $anId, ManufacturerName $aName)
{
$this->id = $anId;
$this->name = $aName;
}
public function name(): ManufacturerName
{
return $this->name;
}
public function slug(): string
{
return $this->slug;
}
// other methods
}
<?php
namespace App\Common\Infrastructure\Domain\Model;
use App\Common\Domain\Model\Sluggable;
use Cocur\Slugify\SlugifyInterface;
use Doctrine\Persistence\Event\LifecycleEventArgs;
class NameSlugger
{
public function __construct(private readonly SlugifyInterface $slugger)
{
}
public function prePersist(LifecycleEventArgs $args): void
{
$this->preSlugged($args);
}
public function preUpdate(LifecycleEventArgs $args): void
{
$this->preSlugged($args);
}
private function preSlugged(LifecycleEventArgs $args): void
{
$entity = $args->getObject();
if (!$entity instanceof Sluggable) {
return;
}
$reflection = $args->getObjectManager()->getClassMetadata($entity::class)->getReflectionClass();
if (!$reflection->hasProperty('slug')) {
throw new \ReflectionException();
}
$reflectionProperty = $reflection->getProperty('slug');
if (!$reflectionProperty->hasType()) {
throw new \ReflectionException();
}
$reflectionPropertyType = $reflectionProperty->getType()->getName();
if ('string' !== $reflectionPropertyType) {
throw new \ReflectionException();
}
$reflectionProperty->setValue(
$entity,
// ManufacturerName VO has a __toString method
$this->slugger->slugify($entity->name())
);
}
}
My question is: is my reasoning valid in your opinion? From a DDD perspective. What different approach would you incorporate so it fits the DDD concept of a project?