node.js - Determining path that express router is bound to without checking request headers -

this question similar this one, can't inspect req.baseurl suggested in answers. reason is, of code in question isn't inside callback.

i want have admin panel '/admin/' page redirecting '/admin/login' when user isn't authenticated.

const cel = require('connect-ensure-login'); const admin = express.router();  admin.get('/login',   (req, res) => {     res.render('login', { path: req.baseurl.splice(1) }); // form action needs know /admin/login path   });  admin.post('/login',   passport.authenticate('local', { failureredirect: '/admin/login' }),   // above 1 of lines in question - since it's not inside (req, res) callback,   // i'm unable access req.baseurl here   (req, res) => {     res.redirect(req.baseurl.splice(1)+'/'); // here full path needed redirect   });  admin.get('/',   cel.ensureloggedin('/admin/login'), // problematic line, same above   (req, res) => {     res.render('adminhome');   });  const app = express(); app.use('/admin', admin); 

many requires , middleware calls skipped conciseness.

how solve? hardcoding paths parameter: '/admin/login' seems against idea of modular structure.