1. Introduction

This tutorial aims to guide you on integrating social authentication using Django Allauth. Social authentication is a form of single sign-on using existing information from a social networking service such as Facebook, Twitter, or Google, to sign into a third-party website, instead of creating a new login account specifically for that website.

In this tutorial, you will learn how to:

• Set up Django Allauth
• Integrate social authentication with Facebook and Google
• Customize the authentication process

Prerequisites:
- Basic knowledge of Django
- Python 3.X and Django installed on your machine

2. Step-by-Step Guide

Firstly, you need to install Django Allauth by running the following command:

pip install django-allauth

After successful installation, add 'allauth' and 'allauth.account' into your INSTALLED_APPS in settings.py:

INSTALLED_APPS = [
    ...
    'django.contrib.sites',
    'allauth',
    'allauth.account',
    'allauth.socialaccount',
    'allauth.socialaccount.providers.google', # for google
    'allauth.socialaccount.providers.facebook', # for facebook
    ...
]

Next, you need to set the SITE_ID variable in settings.py:

SITE_ID = 1

You also need to include allauth.urls in your main urls.py file:

urlpatterns = [
    ...
    path('accounts/', include('allauth.urls')),
    ...
]

3. Code Examples

Example 1: Setting up Google Authentication

To set up Google authentication, you need to create a new project on Google Cloud Console, and then add an OAuth 2.0 client ID. Copy the client ID and client secret.

Then, in your Django admin, go to Social applications and add a new social application. Paste the client ID and client secret into the respective fields and choose Google as the provider.

Example 2: Setting up Facebook Authentication

The process of setting up Facebook authentication is similar to Google. You need to create a new app on Facebook for Developers, and then add a Facebook Login product. Copy the App ID and App Secret.

In your Django admin, go to Social applications and add a new social application. Paste the App ID and App Secret into the respective fields and choose Facebook as the provider.

4. Summary

In this tutorial, you have learned how to set up Django Allauth and integrate social authentication with Google and Facebook. Now you can allow users to log in to your Django app using their Google or Facebook accounts.

For further learning, you can explore more about customizing the authentication process, such as adding extra data fields and handling authentication errors.

5. Practice Exercises

1. Try integrating social authentication with other providers, such as Twitter and GitHub.
2. Customize the login and signup templates to match your site's look and feel.
3. Implement a feature that allows users to link or unlink their social accounts after they have logged in.

Solutions and explanations:
- You can find the list of supported providers in the Django Allauth documentation. The process of integrating other providers is similar to Google and Facebook.
- Django Allauth uses its own templates for login and signup. You can override these templates by creating your own templates with the same name in your app's templates directory.
- Django Allauth provides views for linking and unlinking social accounts. You can include these views in your urls.py to use them.