private function getDocumentClasses()
    {
        /** @var MetadataCollector $metadataCollector */
        $metadataCollector = $this->getContainer()->get('es.metadata_collector');
        $classes = [];

        foreach ($this->getContainer()->getParameter('es.managers') as $manager) {
            $documents = $metadataCollector->getMappings($manager['mappings']);
            foreach ($documents as $document) {
                $classes[] = sprintf('%s:%s', $document['bundle'], $document['class']);
            }
        }

        return $classes;
    }