Login-error page not displayed when using python-social-auth

Question

I am using social-app-django (part of python-social-auth) to implement Facebook login for the users of my Django site. I have a requirement that users must be found in the local user database before they can log in with Facebook. I have replaced the auth_allowed-part of the authentication pipeline, to perform this check:

def auth_allowed(backend, details, response, *args, **kwargs):
    if not backend.auth_allowed(response, details) or not is_registered_user(response, details):
        raise AuthForbidden(backend)

where is_registered_user() is a custom function that checks whether the user exists locally.

My problem is that the users are not redirected to the login error URL , if this check fails and the AuthForbidden exception is thrown. Instead, the site returns a 500.

The error-page URL is configured as follows in settings.py:

LOGIN_ERROR_URL = "/"

I am using Django CMS, so I have also tried implementing middleware that overwrites SocialAuthExceptionMiddleware (which is supposed to handle the AuthForbidden exception in a standard setup) to return a CMS-page instead of an URL from settings.py but this middleware is not invoked in the process, as far as I can see.

Any ideas on how to fix this? Am I missing some configuration?

Answer 1

I think I solved the problem: I accidentally used

social.apps.django_app.middleware.SocialAuthExceptionMiddleware

instead of

social_django.middleware.SocialAuthExceptionMiddleware

when referring to the exception-handling middleware. The bug was most likely introduced during an upgrade from django-social-auth to python-social-auth / social-app-django some time ago.