private function getFilePath($request)
 {
     if (isset($request['file'])) {
         return $request['file'];
     }
     if (isset($request['pgnFile']) && is_numeric($request['pgnFile'])) {
         $file = new ChessFileUpload($request['pgnFile']);
         return $file->getPathOnServer();
     }
     return false;
 }