Get authorized by FB and Gmail in Laravel

In one of my projects, I have added the Facebook and Google+ login to my website. The website is SPA app. The front end is an angular app and the back end laravel 5.1. Login with Facebook and G+ is working perfectly in the front end. But I'm not sure how can I do the authorization in the back end after the user has logged in using the fb or g+ authorization data. Any help will be highly appreciated.

Note: This is my first Laravel project, so any help will be highly expected

via Chebli Mohamed