create-nodeapi-backend/template/javascript/src/middleware/googleMiddleware.js

A powerful Node.js backend boilerplate with Express, MongoDB, Firebase, JWT auth, Nodemailer, cron jobs, input validation (Joi), and serverless support for Vercel. Scaffold a full-featured API backend in seconds.

module.exports.isLoggedIn = (req, res, next) => {
    if (req.user) {
      next();
    } else {
      res.sendStatus(401);
    }
  };