public function put($calendarData)
    {
        if (is_resource($calendarData)) {
            $calendarData = stream_get_contents($calendarData);
        }
        $etag = $this->caldavBackend->updateCalendarObject($this->calendarInfo['id'], $this->objectData['uri'], $calendarData);
        $this->objectData['calendardata'] = $calendarData;
        $this->objectData['etag'] = $etag;

        return $etag;
    }