Logging in does not work after authenticating with custom authentication backend

Question

In my django app, I have written a custom authentication backend following the example in the docs that appears to be working fine. (I email users a login url containing a signed token; the view below handles these token login urls.) I can confirm from the log messages that request.user is being set correctly.

However, the profile view, protected by the @login_required decorator, redirects to the login page as if the user were not logged in. It seems like the call to login is not working. Am I overlooking something? I'm not sure how to debug this further. (As this is my first django app, I decided to write my own login view, and that's working fine...) Thanks!

From views.py:

def token_login(request, token):
    user = authenticate(token=token)
    if user:
        log.info("LOGGING IN {}".format(user))
        login(request, user)
        log.info(request.user)
        return redirect('myapp:profile')
    else:
        return render(request, 'myapp/error.html', {
            'title': 'Invalid Token',
            'message': 'Sorry, this is not a valid login token.'
        })

Custom Authentication Backend:

class TokenBackend:
    """
    Authenticates against a signed token; creates a new user if none existed before.
    """
    def get_user(self, username):
        try:
            User.objects.get(pk=username)
        except User.DoesNotExist:
            return None

    def authenticate(self, token):
        log.info("AUTHENTICATING WITH TOKENBACKEND")
        try:
            token_contents = signing.loads(token, salt=settings.SALT,
                    max_age=settings.PASSWORD_TOKEN_MAX_AGE)
            log.info(token_contents)
        except signing.BadSignature:
            return None
        try:
            user = User.objects.get(email=token_contents['email'])
        except User.DoesNotExist:
            user = User(
                username=self.username_from_email(token_contents['email']),
                password=self.random_password()
            )
        user.save()
        return user

    def random_password(self):
        return ''.join(random.choice(string.ascii_uppercase + string.digits)
                for _ in range(10))

    def username_from_email(self, email):
        return email.split('@')[0]

from settings.py:

AUTHENTICATION_BACKENDS = (
    'myapp.auth.TokenBackend',
    'django.contrib.auth.backends.ModelBackend'
)

Answer 1

Oops. I wasn't returning the User in TokenBackend.get_user.