protected function execute(ConduitAPIRequest $request)
 {
     $fields = $request->getValue('fields');
     $diff = id(new DifferentialDiff())->load($request->getValue('diffid'));
     if (!$diff) {
         throw new ConduitException('ERR_BAD_DIFF');
     }
     $revision = DifferentialRevisionEditor::newRevisionFromConduitWithDiff($fields, $diff, $request->getUser()->getPHID());
     return array('revisionid' => $revision->getID(), 'uri' => PhabricatorEnv::getURI('/D' . $revision->getID()));
 }