Allow users to log in with Google / GitHub

[aubreypc]

In order to simplify the login process, we should use OAuth to allow users to sign in with their existing Google or GitHub accounts.

This blog post might help: https://medium.com/trabe/oauth-authentication-in-django-with-social-auth-c67a002479c1

Additionally, we could allow professors to configure their courses to add a college domain name, so that users who have an email with that domain attached to their Google account are allowed to join the course.

[quigley-c]

What kind of functionality did you want from this feature? What do we need to implement to this end? For now should we just set up the basic login scheme?

[aubreypc]

@quigley-c Here's some more info about the specific tasks I had in mind. A good first prototype would have the first 2 or 3 of these implemented.

• Finding and installing a Django library which allows for OAuth / OpenID authentication
• Performing any necessary configuration to get this library to work with Google / GitHub (getting tokens, etc)
• Writing some kind of User database model which associates an authenticated Google / GitHub account with the existing Professor/Student models
  • Ideally a user should be able to be both a professor and a student in different courses
• Writing views to handle the login process, integrating with the OAuth / OpenID library and with Django's built in authentication framework
• Integrating these login views with the design team's templates
• When progress has been made on #160, certain views should require a user to be logged in / enrolled in a particular course / the owner of a particular course
• Once views have been implemented for joining a course, professors should be able to configure a setting which allows any user whose Google / GitHub account email matches a specified domain name to join the course

And here are some links which might help:

• A tutorial for the social-app-django OAuth / OpenID library
• A tutorial on using Django's built in auth system -- the login and registration stuff won't be relevant, but e.g. we will likely use the login_required decorator on our views.
• Using OAuth with GitHub
• Using OpenID with Google