python-social-auth AuthCanceled exception

Question

I'm using python-social-auth in my Django application for authentication via Facebook. But when a user tries to login and when it's been refirected to Facebook app page clicks on "Cancel" button, appears the following exception:

ERROR 2014-01-03 15:32:15,308 base :: Internal Server Error: /complete/facebook/
Traceback (most recent call last):
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 114, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 57, in wrapped_view
    return view_func(*args, **kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/apps/django_app/utils.py", line 45, in wrapper
    return func(request, backend, *args, **kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/apps/django_app/views.py", line 21, in complete
    redirect_name=REDIRECT_FIELD_NAME, *args, **kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/actions.py", line 54, in do_complete
    *args, **kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/strategies/base.py", line 62, in complete
    return self.backend.auth_complete(*args, **kwargs)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/backends/facebook.py", line 63, in auth_complete
    self.process_error(self.data)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/backends/facebook.py", line 56, in process_error
    super(FacebookOAuth2, self).process_error(data)
  File "/home/vera/virtualenv/myapp/local/lib/python2.7/site-packages/social/backends/oauth.py", line 312, in process_error
    raise AuthCanceled(self, data.get('error_description', ''))
AuthCanceled: Authentication process canceled

Is the any way to catch it Django?

Answer 1

This is slight modification of @Nicolas answer and this works for me.

middleware.py

from social.apps.django_app.middleware import SocialAuthExceptionMiddleware
from django.shortcuts import render
from social.exceptions import AuthCanceled

class SocialAuthExceptionMiddleware(SocialAuthExceptionMiddleware):
    def process_exception(self, request, exception):
        if type(exception) == AuthCanceled:
            return render(request, "pysocial/authcancelled.html", {})
        else:
            pass

settings.py

MIDDLEWARE_CLASSES += (
'myapp.middleware.SocialAuthExceptionMiddleware',
)

Answer 2

Just add in

MIDDLEWARE_CLASSES = ( 'social_auth.middleware.SocialAuthExceptionMiddleware', )

and something like

LOGIN_ERROR_URL = '/'

That's all or read http://django-social-auth.readthedocs.org/en/latest/configuration.html#exceptions-middleware

Answer 3

The 2018 answer:

1. Add SocialAuthExceptionMiddleware middleware to your config:

   MIDDLEWARE_CLASSES = [
       ...
       'social_django.middleware.SocialAuthExceptionMiddleware',
   ]
   

2. Set SOCIAL_AUTH_LOGIN_ERROR_URL in your config:

   SOCIAL_AUTH_LOGIN_ERROR_URL = '/login'
   

Now when you have DEBUG = False, your users will get redirected to your login page when they click cancel in social auth provider's page.

When DEBUG = True you will still see the error page in your browser during development.

Answer 4

This is a updated imports middleware using social_django

from social_django.middleware import SocialAuthExceptionMiddleware
from social_core import exceptions as social_exceptions
from django.shortcuts import HttpResponse
from django.shortcuts import render, redirect

class FacebookAuthCanceledExceptionMiddleware(SocialAuthExceptionMiddleware):

    def process_exception(self, request, exception):
        if hasattr(social_exceptions, 'AuthCanceled'):
            return redirect('auth_login')
        else:
            raise exception

Answer 5

you can create a middleware and catch any exceptions, exception list: https://github.com/omab/python-social-auth/blob/master/social/exceptions.py in this case your AuthCanceled Exception.

middleware.py

    from social.apps.django_app.middleware import SocialAuthExceptionMiddleware
    from django.shortcuts import HttpResponse
    from social import exceptions as social_exceptions

    class SocialAuthExceptionMiddleware(SocialAuthExceptionMiddleware):
        def process_exception(self, request, exception):
            if hasattr(social_exceptions, 'AuthCanceled'):
                return HttpResponse("I'm the Pony %s" % exception)
            else:
                raise exception

settings.py

    MIDDLEWARE_CLASSES = (
             .....
            'pat_to_middleware.SocialAuthExceptionMiddleware',
    )

Answer 6

If you don't care about handling the exception do the following in your settings.py

SOCIAL_AUTH_RAISE_EXCEPTIONS = False

See this answer: How to solve Authentication process canceled error?