express middleware for redirecting to http if a request to nginx came in from http

https-redir-middleware.js

module.exports = function HTTPSRedirect(req, res, next) {
  var env = process && process.env && process.env.NODE_ENV
  if (env !== 'production' || req.headers['x-forwarded-proto'] === 'https' || req.url === '/health') {
    next()
  }
  else {
    res.redirect('https://' + req.hostname + req.url);
  }
}