code: function _parseDuibaUrlQuery(urlQuery, appSecret){
      var urlObj = querystring.parse(_.trimEnd(urlQuery, '&'));
      var md5Sign = genSign(querystring.stringify(_.omit(urlObj,['sign'])), appSecret);
  
      // 将返回结果中的字符串 true/false，转换为 boolean 类型
      var TransDic = {
          'true': true,
          'false': false
      };
      for(var key in urlObj){
          var value = urlObj[key];
          urlObj[key] = typeof TransDic[value] === 'boolean' ? TransDic[value] : value;
      }
  
      if(md5Sign !== urlObj.sign){
          return {
              sign_pass: false,
              params: urlObj
          };
      }else{
          return {
              sign_pass: true,
              params: urlObj
          };
      }
  }
docs: ********** 私有函数 ************* 
  通用参数解析接口