Expressjs / Change header before passportjs response

Question

I am trying to change the header challenge sent in WWW-Authenticate header in Nodejs.

Using passportjs, my current server code is the following:

router.route('/login/')

    .get(function(req, res){

        if(req.isAuthenticated()) res.redirect('/admin/');
        else res.render('admin/partials/login.html');
    })

    .post(passport.authenticate('digest'));

The problem I am facing is that digest authorization first send a 401 code response (that's the normal way to go), but most browsers (webkit at least), launch a prompt popin asking user to authenticate when they detect such challenge (Digest or Basic) in header.

I read that a solution could be to change the header, modifying WWW-Authenticate:Digest to WWW-Authenticate:xDigest for example, but I don't find a way to do it in Express.

I think that the middleware passport.authenticate must set the header and I can not find a way to change it before the response is sent to the client (in the same middleware I think).

Thanks for any ideas.

Answer 1

Ok, I just find that passportjs provides an easy way to adjust the response as whishes with Custom Callback.

If it can help anyone, here is the way I had to go :

router.route('/login/')

    .post(function(req, res, next){

        passport.authenticate('digest', function(err, user, info){

            if(err) return console.log(err);

            if(!user){
                res.set('WWW-Authenticate', 'x'+info);
                return res.send(401);
            }

            req.login(user, function(err){
                if(err) return console.log(err);
                res.redirect('/admin/');
            });
        })(req, res, next);
    });

As you can see, the authenticate method is called inside a middleware and not as a middleware itself.