BundleConstraint.php

<?php

namespace Drupal\Core\Entity\Plugin\Validation\Constraint;

use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\Validation\Attribute\Constraint;
use Symfony\Component\Validator\Constraint as SymfonyConstraint;

/**
 * Checks if a value is a valid entity type.
 *
 * This differs from the `EntityBundleExists` constraint in that checks that the
 * validated value is an *entity* of a particular bundle.
 */
class BundleConstraint extends SymfonyConstraint {
  
  /**
   * The default violation message.
   *
   * @var string
   */
  public $message = 'The entity must be of bundle %bundle.';
  
  /**
   * The bundle option.
   *
   * @var string|array
   */
  public $bundle;
  
  /**
   * Gets the bundle option as array.
   *
   * @return array
   *   An array of bundle options.
   */
  public function getBundleOption() {
    // Support passing the bundle as string, but force it to be an array.
    if (!is_array($this->bundle)) {
      $this->bundle = [
        $this->bundle,
      ];
    }
    return $this->bundle;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getDefaultOption() : ?string {
    return 'bundle';
  }
  
  /**
   * {@inheritdoc}
   */
  public function getRequiredOptions() : array {
    return [
      'bundle',
    ];
  }

}