GraphMLWriter.outputGraph(tx, path);
} else if (format.equalsIgnoreCase("GML")) {
path = new File(git.getRepository().getWorkTree(), graphId + ".gml").getPath();
GMLWriter.outputGraph(tx, path);
} else {
tx.rollback();
response.put("status", "error");
response.put("msg", "unknown format '" + format + "'");
return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
}