cforge-2.0.x-dev/modules/cforge_address/src/MigrationSubscriber.php

<?php

namespace Drupal\cforge_address;

use Drupal\migrate\Event\MigrateImportEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;


/**
 * Migration modifications
 *
 * Note the order of events in MigrateExecutable::import
 * Dispatch PRE_IMPORT
 *  $source->next
 *  $source->prepareRow
 *    hook_migrate_prepare_row
 *    hook_migrate_NAME_prepare_row
 *  while
 *    processRow
 *    Dispatch PRE_ROW_SAVE
 *    Dispatch POST_ROW_SAVE
 *  Dispatch POST_IMPORT
 *
 */
class MigrationSubscriber implements EventSubscriberInterface {

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() : array {
    return [
      'migrate.post_import' => [['migratePostImport']]
    ];
  }


  /**
   * @param Drupal\migrate\Event\MigratePreRowSaveEvent $event
   */
  function migratePostImport(MigrateImportEvent $event) {
    $all = \Drupal\cforge_address\Entity\Neighbourhood::loadMultiple();
    if (count($all) < 2) {
      \Drupal::service('module_installer')->uninstall(['cforge_address']);
    }
  }

}