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(),
        ]);
    }
}