FOSElasticaBundle/Resources/doc/cookbook/custom-properties.md

Custom Properties

Since FOSElasticaBundle 3.1.0, we now dispatch an event for each transformation of an object into an Elastica document which allows you to set custom properties on the Elastica document for indexing.

Set up an event listener or subscriber for FOS\ElasticaBundle\Event\TransformEvent::POST_TRANSFORM to be able to inject your own parameters.

class CustomPropertyListener implements EventSubscriberInterface
{
    private $anotherService;
    
    // ...
    
    public function addCustomProperty(TransformEvent $event)
    {
        $document = $event->getDocument();
        $custom = $this->anotherService->calculateCustom($event->getObject());
                    
        $document->set('custom', $custom);
    }
    
    public static function getSubscribedEvents()
    {
        return array(
            TransformEvent::POST_TRANSFORM => 'addCustomProperty',
        );
    }
}