Passport JS "Can't Set Headers After They Are Sent"

Getting this error when I successfully log in with passport JS. Trying to redirect to the home page once I log in. Code that does it: app.post('/login', passport.authenticate('l

Solution 1:

You are redirecting the user so serializeUser function is being called twice. And in

 passport.use(new FacebookStrategy({
 ...

be sure to add this else or it gets called twice, thus sending the headers twice and causing error. Try this:

passport.use(new FacebookStrategy({
...
},
function(accessToken, refreshToken, profile, done) {
// asynchronous verification, for effect...
process.nextTick(function () {

  // To keep the example simple, the user's Facebook profile is returned to
  // represent the logged-in user.  In a typical application, you would want
  // to associate the Facebook account with a user record in your database,
  // and return that user instead.
    User.findByFacebookId({facebookId: profile.id}, function(err, user) {
        if (err) { return done(err); }
        if (!user) {
            //create user User.create...
            return done(null, createdUser);
        } else { //add this else
            return done(null, user);
        }
    });
  });
 }
));