public function getDraftCollectionAction()
    {
        $contents = $this->getEntityManager()
            ->getRepository('BackBee\ClassContent\Revision')
            ->getAllDrafts($this->getApplication()->getBBUserToken())
        ;

        $contents = $this->sortDraftCollection($contents);

        return $this->addContentRangeHeadersToResponse($this->createJsonResponse($contents), $contents, 0);
    }