Slugify using Symfony 7+ and Doctrine 3+

Example.php

<?php

class Example
{
    #[ORM\Column(length: 255)]
    private string $name;

    #[ORM\Column(length: 255, unique: true)]
    #[Slug(targetProperty: 'name', unique: true)]
    private string $slug;
}

Slug.php

<?php

declare(strict_types=1);

namespace App\Tooling\Doctrine\Slug;

#[\Attribute(\Attribute::TARGET_PROPERTY)]
class Slug
{
    public function __construct(
        public string $targetProperty,
        public bool $unique = true,
        public bool $updateOnChange = false
    ) {
        if (true === $this->updateOnChange) {
            throw new \Exception('This behavior is not supported yet, please change the SlugifyListener to add its support.');
        }
    }
}

SlugifyListener.php

<?php

declare(strict_types=1);

namespace App\Tooling\Doctrine\Slug;

use Doctrine\Bundle\DoctrineBundle\Attribute\AsDoctrineListener;
use Doctrine\ORM\Event\PrePersistEventArgs;
use Symfony\Component\PropertyAccess\PropertyAccessorInterface;
use Symfony\Component\String\Slugger\AsciiSlugger;

#[AsDoctrineListener('prePersist')]
class SlugifyListener
{
    public function __construct(private PropertyAccessorInterface $accessor)
    {
    }

    public function prePersist(PrePersistEventArgs $args): void
    {
        $entity = $args->getObject();
        $reflection = new \ReflectionObject($entity);
        $entityManager = $args->getObjectManager();

        foreach ($reflection->getProperties() as $property) {
            /** @var \ReflectionAttribute<Slug>[] $attributes */
            $attributes = $property->getAttributes(Slug::class);

            if (empty($attributes)) {
                continue;
            }

            /** @var Slug $slugAttribute */
            $slugAttribute = $attributes[0]->newInstance();
            $slug = $this->slugify(
                $entity,
                $property,
                $slugAttribute
            );

            if (empty($slug)) {
                return;
            }

            if ($slugAttribute->unique) {
                $metadata = $entityManager->getClassMetadata($entity::class);
                $table = $metadata->getTableName();
                $sqlField = $metadata->getColumnName($property->getName());

                $connection = $entityManager->getConnection();
                $resultSet = $connection->executeQuery(<<<SQL
                    SELECT $sqlField FROM $table WHERE $sqlField LIKE '$slug%'
                SQL)->fetchAllAssociative();

                if (!empty($resultSet)) {
                    $slug = $this->incrementSlug(array_map(fn ($item) => $item['slug'], $resultSet), $slug);
                    $this->accessor->setValue($entity, $property->getName(), $slug);
                }
            }
        }
    }

    /**
     * @param array<string, string>|null $changeSet
     */
    private function slugify(object $entity, \ReflectionProperty $property, Slug $slugAttribute, ?array $changeSet = null, bool $isUpdate = false): ?string
    {
        if (null !== $changeSet && !\array_key_exists($slugAttribute->targetProperty, $changeSet)) {
            return null;
        }

        if ($isUpdate && $slugAttribute->updateOnChange) {
            return $this->accessor->getValue($entity, $property->getName());
        }

        $originalValue = $this->accessor->getValue($entity, $slugAttribute->targetProperty);
        $slug = (new AsciiSlugger())->slug($originalValue)->toString();
        $this->accessor->setValue($entity, $property->getName(), $slug);

        return $slug;
    }

    /**
     * @param array<int, string> $slugsInDatabase
     */
    private function incrementSlug(array $slugsInDatabase, string $slug): string
    {
        if (1 === \count($slugsInDatabase)) {
            return $slug . '-1';
        }

        if (1 !== preg_match('/-(\d+)$/', $slugsInDatabase[0], $matches)) {
            return $slug . '-1';
        }

        $i = ((int) $matches[1]) + 1;

        return $slug . '-' . $i;
    }
}