Redirect Back to App

In the previous section, you added session support to the app in order to maintain state when redirecting to Google. In this section, you'll add a route that authenticates the user when Google redirects them back to the app.

Open routes/auth.js and add the following code at line 55, below the /login/federated/google route.

router.get('/oauth2/redirect/google', passport.authenticate('google', {
  successRedirect: '/',
  failureRedirect: '/login'
}));

The app now has routes that handle the complete cycle of redirecting to Google and from Google back to the app, with state maintained in between. Try signing in by starting the server.

$ npm start

Open http://localhost:3000, click "Sign in" and then click "Sign in with Google."

Uh oh... the app fails with an error related to sessions. Next, you will fix that error by configuring Passport to establish a session.