PartKeepr\CategoryBundle\Action\GetRootNodeAction::__invoke PHP Method

    public function __invoke(Request $request)
    {
        list($resourceType) = $this->extractAttributes($request);
        /*
         * @var ResourceInterface $resourceType
         */
        $repository = $this->manager->getRepository($resourceType->getEntityClass());
        /*
         * @var $repository AbstractTreeRepository
         */
        $rootNodes = $repository->getRootNodes();
        if (count($rootNodes) == 0) {
            throw new RootNodeNotFoundException();
        }
        $rootNode = reset($rootNodes);
        return $rootNode;
    }