RoleExistsConstraintValidator.php

<?php

declare (strict_types=1);
namespace Drupal\user\Plugin\Validation\Constraint;

use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;

/**
 * Validates that a role exists.
 */
class RoleExistsConstraintValidator extends ConstraintValidator implements ContainerInjectionInterface {
  
  /**
   * Create a new RoleExistsConstraintValidator instance.
   *
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager.
   */
  public function __construct(private readonly EntityTypeManagerInterface $entity_type_manager) {
  }
  
  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) : static {
    return new static($container->get(EntityTypeManagerInterface::class));
  }
  
  /**
   * {@inheritdoc}
   */
  public function validate($value, Constraint $constraint) : void {
    assert($constraint instanceof RoleExistsConstraint);
    if (!is_string($value)) {
      throw new UnexpectedTypeException($value, 'string');
    }
    $roleStorage = $this->entity_type_manager
      ->getStorage('user_role');
    if (!$roleStorage->load($value)) {
      $this->context
        ->addViolation($constraint->message, [
        '@rid' => $value,
      ]);
    }
  }

}