code: function sendOriginalResponse(clientRes, response) {
      clientRes.writeHead(response.statusCode, response.headers);
      response.pipe(clientRes);
  }
docs: Transform server response content.
  
  There's no error value, because even if the transform fails, *something* should be returned
  to the client. Figuring out what that should be is application-specific (i.e, your problem).
  
  @callback transformCallback
  @param {Buffer} input - The server's response content.
  @returns {Buffer} - The transformed response.
   
  Send a server response to the proxy client as-is, without modification.
  
  @param {http.ServerResponse} clientRes - Response to the client.
  @param {http.IncomingMessage} response - Response from the server (to send).