code: function reqURL(req, newPath) {
    return url.format({
      protocol: 'https', //req.protocol, // by default this returns http which gets redirected
      host: req.get('host'),
      pathname: newPath
    })
  }
docs: Retrieve the URL for another endpoint running on the same server, on https.
  
  @param req The express/firebase function request object
  @param newPath The endpoint
  @returns {string} The URL