Same name and namespace in other branches
  1. 8.9.x core/modules/migrate/src/Plugin/migrate/process/MakeUniqueBase.php \Drupal\migrate\Plugin\migrate\process\MakeUniqueBase
  2. 9 core/modules/migrate/src/Plugin/migrate/process/MakeUniqueBase.php \Drupal\migrate\Plugin\migrate\process\MakeUniqueBase

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\migrate\Plugin\migrate\process\MakeUniqueBase extends \Drupal\migrate\ProcessPluginBase

Expanded class hierarchy of 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
View source 
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 = $this->configuration['postfix'] ?? '';
    $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 = $this->configuration['length'] ?? NULL;
    if (!is_null($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

Namesort descending Modifiers Type Description Overrides
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.