/**
  * Find a partial by it's slug.
  *
  * @param $slug
  * @return null|PartialInterface
  */
 public function findBySlug($slug)
 {
     return $this->model->where('slug', $slug)->first();
 }
 /**
  * Return an index of existing fields.
  *
  * @param FieldTableBuilder $table
  * @return \Symfony\Component\HttpFoundation\Response
  */
 public function index(FieldTableBuilder $table, PartialModel $partials)
 {
     $table->setStream($partials->getStream());
     return $table->render();
 }