protected function _addQueryLogsNode($json)
    {
        $listener = $this->_getApiQueryLogListenerObject();
        $logs = $listener->getQueryLogs();

        if (empty($logs)) {
            return $json;
        }

        $result = json_decode($json, true);
        $result['query'] = $logs;

        return json_encode($result, JSON_PRETTY_PRINT);
    }