Elastica\Query::addAggregation PHP Method

    public function addAggregation(AbstractAggregation $agg)
    {
        $this->_params['aggs'][] = $agg;
        return $this;
    }

 public function indexAction(Request $request, $page = 1)
 {
     $getTypes = $request->query->get('type_filters');
     $getSubjects = $request->query->get('subject_filters');
     $getPublishers = $request->query->get('publisher_filters');
     $typeFilters = !empty($getTypes) ? explode(',', $getTypes) : [];
     $subjectFilters = !empty($getSubjects) ? explode(',', $getSubjects) : [];
     $publisherFilters = !empty($getPublishers) ? explode(',', $getPublishers) : [];
     $journalSearcher = $this->get('fos_elastica.index.search.journal');
     $boolQuery = new Query\Bool();
     $match = new Query\Match();
     $match->setField('status', 1);
     $boolQuery->addMust($match);
     $match = new Query\Match();
     $match->setField('published', true);
     $boolQuery->addMust($match);
     if (!empty($typeFilters) || !empty($subjectFilters) || !empty($publisherFilters)) {
         foreach ($typeFilters as $type) {
             $match = new Query\Match();
             $match->setField('publisher.publisher_type.name', $type);
             $boolQuery->addMust($match);
         }
         foreach ($subjectFilters as $subject) {
             $match = new Query\Match();
             $match->setField('subjects.subject', $subject);
             $boolQuery->addMust($match);
         }
         foreach ($publisherFilters as $publisher) {
             $match = new Query\Match();
             $match->setField('publisher.name', $publisher);
             $boolQuery->addMust($match);
         }
     }
     $journalQuery = new Query($boolQuery);
     $typeAgg = new Aggregation\Terms('types');
     $typeAgg->setField('publisher.publisher_type.name');
     $typeAgg->setOrder('_term', 'asc');
     $typeAgg->setSize(0);
     $journalQuery->addAggregation($typeAgg);
     $subjectAgg = new Aggregation\Terms('subjects');
     $subjectAgg->setField('subjects.subject');
     $subjectAgg->setOrder('_term', 'asc');
     $subjectAgg->setSize(0);
     $journalQuery->addAggregation($subjectAgg);
     $publisherAgg = new Aggregation\Terms('publishers');
     $publisherAgg->setField('publisher.name');
     $publisherAgg->setOrder('_term', 'asc');
     $publisherAgg->setSize(0);
     $journalQuery->addAggregation($publisherAgg);
     $adapter = new ElasticaAdapter($journalSearcher, $journalQuery);
     $pagerfanta = new Pagerfanta($adapter);
     $pagerfanta->setMaxPerPage(21);
     $pagerfanta->setCurrentPage($page);
     $journals = $pagerfanta->getCurrentPageResults();
     $types = $adapter->getResultSet()->getAggregation('types')['buckets'];
     $subjects = $adapter->getResultSet()->getAggregation('subjects')['buckets'];
     $publishers = $adapter->getResultSet()->getAggregation('publishers')['buckets'];
     $data = ['types' => $types, 'subjects' => $subjects, 'publishers' => $publishers, 'type_filters' => $typeFilters, 'subject_filters' => $subjectFilters, 'publisher_filters' => $publisherFilters, 'journals' => $journals, 'pagerfanta' => $pagerfanta, 'page' => 'explore'];
     return $this->render('OjsSiteBundle:Explore:index.html.twig', $data);
 }