app.get('/auth/facebook/menu', function(req,res,next) {
// url parameter ?state=subpage is passed to login
// this can be used for routing after callback
let param = req.query.state;
passport.authenticate('facebook', { state: param })(req,res,next);
});
app.get('/auth/facebook/callback', passport.authenticate(
'facebook',
{ failureRedirect: '/' }),
function(req, res) {
let state = req.query.state;
// redirect user depending from
// where he came from
switch(state) {
case 'subpage':
res.redirect('/subpage');
break;
default:
res.redirect('/');
}
});