code: function useGatewayAuthentication(req) {
    // can be set on request if via application supplied callback
    if (req.useGateway == true) { return true; }
  
    // otherwise via query parameter
    var origUrl = req.originalUrl;
    var useGateway = false;
    var idx = origUrl.indexOf(gatewayParameter);
    if (idx >= 0) {
      useGateway = true;
    }
  
    return useGateway;
  }
docs: Check if we are requested to perform a gateway signon, i.e. a check