flash message returning [object Object] (Node Express Passport)

Question

I am using passport.js and want to return a flash message if username or password are inoccorect setup. All the logic is set up, and it worked before. But i somehow broke the function and its still not working even though i copied the working version 1 by 1. I have flash messaging setup in my application, which works flawlessly for all the other flash messages which don't involve passport.js.

But if i try to log in, my flash message is empty and i receive [object Object] as a console.log.

Question 1 : Is there a way to access all the information that [object Object] represents?

Question 2 : Is there a way to console.log what is being flashed before its displayed? How would i access that part of the sessions?

Route:

router.post('/',
    passport.authenticate('local', { successRedirect: '/', failureRedirect: '/login', failureFlash: true }),
  function(req, res) {
    console.log('Login success.');
});

Passport Code that sends flash message for context:

passport.use(new LocalStrategy(
  function(username, password, done) {
    User.getUserByUsername(username, function(err, user){
      if (err) throw err;
      if (!user) {
        console.log('A user tried logging in, but username input returned unknown.');
        return done(null, false, {message: 'Unknown user.'});
      }
      User.comparePassword(password, user.password, function(err, isMatch){
        if(err) throw err;
        if(isMatch) {
          return done(null, user);
        } else {
          console.log('A user tried logging in, but password input returned invalid.');
          return done(null, false, {message: 'Invalid password.'});
        }
     });
    });
  }
));

Showing the message with handlebars in my view:

{{#if error_msg}}
  <div class="alert alert-danger">{{error_msg}}</div>
{{/if}}
{{#if error}}
  <div class="alert alert-danger">{{error}}</div>
{{/if}}

(in my older branch that is working, its returning with error_msg -- in my current branch its returning just error with the [object Object] console.log)

Thanks in advance!

Answer 1

Fixed issue by removing the handlebars-helpers library which introduced some issue in regards to flash messaging. (only in combination with how Passport handles flash messages)