Language.php

<?php

namespace Drupal\language\Plugin\migrate\source;

use Drupal\migrate\Row;
use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;

/**
 * Drupal 6/7 language source from database.
 *
 * Available configuration keys:
 * - fetch_all: (optional) If not empty, all source languages are retrieved and
 *   available as "languages" source property. Each language is an array with
 *   the same structure as a source row.
 * - domain_negotiation: (optional) If not empty and domain negotiation is
 *   enabled in the source database, the "domain_negotiation_used" source
 *   property is set to TRUE.
 *
 * Example:
 *
 * @code
 * plugin: language
 * fetch_all: true
 * domain_negotiation: true
 * @endcode
 *
 * In this example, available languages are retrieved from the source database.
 * Given that fetch_all and domain_negotiation are specified, each row also
 * contains all languages and the domain negotiation status, if enabled.
 *
 * For additional configuration keys, refer to the parent classes.
 *
 * @see \Drupal\migrate\Plugin\migrate\source\SqlBase
 * @see \Drupal\migrate\Plugin\migrate\source\SourcePluginBase
 *
 * @MigrateSource(
 *   id = "language",
 *   source_module = "locale"
 * )
 */
class Language extends DrupalSqlBase {

  /**
   * {@inheritdoc}
   */
  public function fields() {
    return [
      'language' => $this
        ->t('The language code.'),
      'name' => $this
        ->t('The English name of the language.'),
      'native' => $this
        ->t('The native name of the language.'),
      'direction' => $this
        ->t('The language direction. (0 = LTR, 1 = RTL)'),
      'enabled' => $this
        ->t('Whether the language is enabled.'),
      'plurals' => $this
        ->t('Number of plural indexes in this language.'),
      'formula' => $this
        ->t('PHP formula to get plural indexes.'),
      'domain' => $this
        ->t('Domain to use for this language.'),
      'prefix' => $this
        ->t('Path prefix used for this language.'),
      'weight' => $this
        ->t('The language weight when listed.'),
      'javascript' => $this
        ->t('Location of the JavaScript translation file.'),
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function getIds() {
    return [
      'language' => [
        'type' => 'string',
      ],
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function query() {
    return $this
      ->select('languages')
      ->fields('languages');
  }

  /**
   * {@inheritdoc}
   */
  public function prepareRow(Row $row) {
    if (!empty($this->configuration['fetch_all'])) {

      // Get an array of all languages.
      $languages = $this
        ->query()
        ->execute()
        ->fetchAll();
      $row
        ->setSourceProperty('languages', $languages);
    }
    if (!empty($this->configuration['domain_negotiation'])) {

      // Check if domain negotiation is used to be able to fill in the default
      // language domain, which may be empty. In D6, domain negotiation is used
      // when the 'language_negotiation' variable is set to '3', and in D7, when
      // the 'locale_language_negotiation_url_part' variable is set to '1'.
      if ($this
        ->variableGet('language_negotiation', 0) == 3 || $this
        ->variableGet('locale_language_negotiation_url_part', 0) == 1) {
        $row
          ->setSourceProperty('domain_negotiation_used', TRUE);
      }
    }
    return parent::prepareRow($row);
  }

}