class NullCoalesce

Provides a Null Coalesce process plugin.

Given a set of values provided to the plugin, the plugin will return the first non-null value.

Available configuration keys:

• source: The input array.
• default_value: (optional) The value to return if all values are NULL. if not provided, NULL is returned if all values are NULL.

Example: Given source keys of foo, bar, and baz:

process_key:
  plugin: null_coalesce
  source:
    - foo
    - bar
    - baz

This plugin will return the equivalent of `foo ?? bar ?? baz`

Plugin annotation

@MigrateProcessPlugin(
  id = "null_coalesce"
)

Hierarchy

• class \Drupal\Component\Plugin\PluginBase implements \Drupal\Component\Plugin\PluginInspectionInterface, \Drupal\Component\Plugin\DerivativeInspectionInterface
  • class \Drupal\Core\Plugin\PluginBase uses \Drupal\Core\StringTranslation\StringTranslationTrait, \Drupal\Core\DependencyInjection\DependencySerializationTrait, \Drupal\Core\Messenger\MessengerTrait extends \Drupal\Component\Plugin\PluginBase
    • class \Drupal\migrate\ProcessPluginBase implements \Drupal\migrate\Plugin\MigrateProcessInterface extends \Drupal\Core\Plugin\PluginBase
      • class \Drupal\migrate\Plugin\migrate\process\NullCoalesce extends \Drupal\migrate\ProcessPluginBase

Expanded class hierarchy of NullCoalesce

File

core/modules/migrate/src/Plugin/migrate/process/NullCoalesce.php, line 37

Namespace

class NullCoalesce extends ProcessPluginBase {
  
  /**
   * {@inheritdoc}
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
    if (!is_array($value)) {
      throw new MigrateException("The input value should be an array.");
    }
    foreach ($value as $val) {
      if (NULL !== $val) {
        return $val;
      }
    }
    if (isset($this->configuration['default_value'])) {
      return $this->configuration['default_value'];
    }
    return NULL;
  }

}

Members