abstract class MakeUniqueBase in Drupal 8

This plugin ensures the source value is unique.

The MakeUniqueBase process plugin is used to avoid duplication at the destination. For example, when creating filter format names, the source value is checked against the existing filter format names and if it exists, a numeric postfix is added and incremented until a unique value is created. An optional postfix string can be insert before the numeric postfix.

Available configuration keys

• start: (optional) The position at which to start reading.
• length: (optional) The number of characters to read.
• postfix: (optional) A string to insert before the numeric postfix.

Hierarchy

• class \Drupal\Component\Plugin\PluginBase implements DerivativeInspectionInterface, PluginInspectionInterface
  • class \Drupal\Core\Plugin\PluginBase uses DependencySerializationTrait, MessengerTrait, StringTranslationTrait
    • class \Drupal\migrate\ProcessPluginBase implements MigrateProcessInterface
      • class \Drupal\migrate\Plugin\migrate\process\MakeUniqueBase

See also

\Drupal\migrate\Plugin\MigrateProcessInterface

File

core/modules/migrate/src/Plugin/migrate/process/MakeUniqueBase.php, line 26

Namespace

Drupal\migrate\Plugin\migrate\process

abstract class MakeUniqueBase extends ProcessPluginBase {

  /**
   * Creates a unique value based on the source value.
   *
   * @param string $value
   *   The input string.
   * @param \Drupal\migrate\MigrateExecutableInterface $migrate_executable
   *   The migration in which this process is being executed.
   * @param \Drupal\migrate\Row $row
   *   The row from the source to process.
   * @param string $destination_property
   *   The destination property currently worked on. This is only used together
   *   with the $row above.
   *
   * @return string
   *   The unique version of the input value.
   *
   * @throws \Drupal\migrate\MigrateException
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
    $i = 1;
    $postfix = isset($this->configuration['postfix']) ? $this->configuration['postfix'] : '';
    $start = isset($this->configuration['start']) ? $this->configuration['start'] : 0;
    if (!is_int($start)) {
      throw new MigrateException('The start position configuration key should be an integer. Omit this key to capture from the beginning of the string.');
    }
    $length = isset($this->configuration['length']) ? $this->configuration['length'] : NULL;
    if (!is_null($length) && !is_int($length)) {
      throw new MigrateException('The character length configuration key should be an integer. Omit this key to capture the entire string.');
    }

    // Use optional start or length to return a portion of the unique value.
    $value = mb_substr($value, $start, $length);
    $new_value = $value;
    while ($this
      ->exists($new_value)) {
      $new_value = $value . $postfix . $i++;
    }
    return $new_value;
  }

  /**
   * This is a query checking the existence of some value.
   *
   * @param mixed $value
   *   The value to check.
   *
   * @return bool
   *   TRUE if the value exists.
   */
  protected abstract function exists($value);

}

Members

Name	Modifiers	Type	Description	Overrides
DependencySerializationTrait::$_entityStorages	protected	property	An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds	protected	property	An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep	public	function		1
DependencySerializationTrait::__wakeup	public	function		2
MakeUniqueBase::exists	abstract protected	function	This is a query checking the existence of some value.	1
MakeUniqueBase::transform	public	function	Creates a unique value based on the source value. Overrides ProcessPluginBase::transform
MessengerTrait::$messenger	protected	property	The messenger.	29
MessengerTrait::messenger	public	function	Gets the messenger.	29
MessengerTrait::setMessenger	public	function	Sets the messenger.
PluginBase::$configuration	protected	property	Configuration information passed into the plugin.	1
PluginBase::$pluginDefinition	protected	property	The plugin implementation definition.	1
PluginBase::$pluginId	protected	property	The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR		constant	A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId	public	function	Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId	public	function	Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginDefinition	public	function	Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition	3
PluginBase::getPluginId	public	function	Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable	public	function	Determines if the plugin is configurable.
PluginBase::__construct	public	function	Constructs a \Drupal\Component\Plugin\PluginBase object.	92
ProcessPluginBase::multiple	public	function	Indicates whether the returned value requires multiple handling. Overrides MigrateProcessInterface::multiple	3
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	1
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.