passport: different redirect for login and account registration

Question

i'm using the passport module (github authentication) in my app and i want to redirect depending on the action ... i check if it's just a normal login or if the user logs in for the first time.

passport.use(new GitHubStrategy({
    clientID: conf.github.app_id,
    clientSecret: conf.github.app_secret,
    callbackURL: conf.github.callback_url
  },
  function(accessToken, refreshToken, profile, done) {
    // asynchronous verification, for effect...
    process.nextTick(function () {

      // To keep the example simple, the user's GitHub profile is returned to
      // represent the logged-in user.  In a typical application, you would want
      // to associate the GitHub account with a user record in your database,
      // and return that user instead.

      Models_User.findOrCreateUser(profile, function(msg){
        console.log("auth type:" + msg);
      });

      return done(null, profile);

    });
  }
));

in my findOrCreateUser function i check if it's a new user and do all the db action ... for testing i let the function return a msg variable which is only a string that says "login" or "new_registration".

so my question is how to "transport" that variable that i get from findOrCreateUser so that i can redirect accordingly ("/welcome" or "/back_again") after the passport auth is finished.

the other passport code in my app:

// GET /auth/github
//   Use passport.authenticate() as route middleware to authenticate the
//   request.  The first step in GitHub authentication will involve redirecting
//   the user to github.com.  After authorization, GitHubwill redirect the user
//   back to this application at /auth/github/callback
app.get('/auth/github',
  passport.authenticate('github'),
  //passport.authenticate('github', { scope: ['user', 'public_repo', 'gist'] }),
  function(req, res){
    // The request will be redirected to GitHub for authentication, so this
    // function will not be called.
  });

// GET /auth/github/callback
//   Use passport.authenticate() as route middleware to authenticate the
//   request.  If authentication fails, the user will be redirected back to the
//   login page.  Otherwise, the primary route function function will be called,
//   which, in this example, will redirect the user to the home page.
app.get('/auth/github/callback', 
  passport.authenticate('github', { successRedirect: '/', failureRedirect: '/login' }),
  function(req, res) {
    res.redirect('/');
  });

Answer 1

In your verify callback, I would change things up so that the findOrCreateUser function supplies the actual record to the callback, and then pass that through to done(), like so:

Models_User.findOrCreateUser(profile, function(user){
  console.log("auth type:" + msg);
  return done(null, user);
});

// take this out, use the actual model above
//return done(null, profile);

Now, when handling the callback URL after authentication, you can check this user record and see if it was new (I'm assuming it has an isNew property here):

app.get('/auth/github/callback', 
  passport.authenticate('github', { failureRedirect: '/login' }),
  function(req, res) {
    // successful auth, user is set at req.user.  redirect as necessary.
    if (req.user.isNew) { return res.redirect('/back_again'); }
    res.redirect('/welcome');
  });