function UniqueFieldValueValidator::validate

File

core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/UniqueFieldValueValidator.php, line 16

Class

UniqueFieldValueValidator

Validates that a field is unique for the given entity type.

Namespace

Code

public function validate($items, Constraint $constraint) {
  if (!($item = $items->first())) {
    return;
  }
  $field_name = $items->getFieldDefinition()
    ->getName();
  /** @var \Drupal\Core\Entity\EntityInterface $entity */
  $entity = $items->getEntity();
  $entity_type_id = $entity->getEntityTypeId();
  $id_key = $entity->getEntityType()
    ->getKey('id');
  $query = \Drupal::entityQuery($entity_type_id);
  // @todo Don't check access. http://www.drupal.org/node/3171047
  $query->accessCheck(TRUE);
  $entity_id = $entity->id();
  // Using isset() instead of !empty() as 0 and '0' are valid ID values for
  // entity types using string IDs.
  if (isset($entity_id)) {
    $query->condition($id_key, $entity_id, '<>');
  }
  $value_taken = (bool) $query->condition($field_name, $item->value)
    ->range(0, 1)
    ->count()
    ->execute();
  if ($value_taken) {
    $this->context
      ->addViolation($constraint->message, [
      '%value' => $item->value,
      '@entity_type' => $entity->getEntityType()
        ->getSingularLabel(),
      '@field_name' => $items->getFieldDefinition()
        ->getLabel(),
    ]);
  }
}