code: function convertToCompressedRequest(req, res, compression) {
          var type = mime.lookup(req.path);
          var charset = mime.charsets.lookup(type);
          var search = req.url.split('?').splice(1).join('?');
  
          if (search !== "") {
              search = "?" + search;
          }
  
          req.url = req.path + compression.fileExtension + search;
          res.setHeader("Content-Encoding", compression.encodingName);
          res.setHeader("Content-Type", type + (charset ? "; charset=" + charset : ""));
      }
docs: Changes the url and adds required headers to serve a compressed file.
  @param {Object} req
  @param {Object} res