Skip to content

Events System

When to Use

Use this when hooking into Search API's query or indexing pipeline without creating full custom processors.

Decision

Event Constant Class When Use Case
INDEXING_ITEMS IndexingItemsEvent Before items indexed Modify items pre-indexing
ITEMS_INDEXED ItemsIndexedEvent After items indexed Trigger post-indexing actions
REINDEX_SCHEDULED ReindexScheduledEvent Reindex triggered Notification
QUERY_PRE_EXECUTE QueryPreExecuteEvent Before backend executes Modify query at last moment
PROCESSING_RESULTS ProcessingResultsEvent After backend returns Modify raw results

Pattern

# my_module.services.yml
services:
  my_module.search_api_subscriber:
    class: Drupal\my_module\EventSubscriber\SearchApiSubscriber
    tags:
      - { name: event_subscriber }

namespace Drupal\my_module\EventSubscriber;

use Drupal\search_api\Event\QueryPreExecuteEvent;
use Drupal\search_api\Event\SearchApiEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class SearchApiSubscriber implements EventSubscriberInterface {

  public static function getSubscribedEvents(): array {
    return [SearchApiEvents::QUERY_PRE_EXECUTE => 'onQueryPreExecute'];
  }

  public function onQueryPreExecute(QueryPreExecuteEvent $event): void {
    $query = $event->getQuery();
    $query->addCondition('status', TRUE);
  }
}

Common Mistakes

  • Wrong: Using hooks instead of events → Right: Search API 1.x uses Symfony events. Use event subscribers, not hook implementations.

See Also