Django login method gives recursion error - django

Question

I tried making a custom authentication view that saves the user in the session using login(request, user) but it gives me
maximum recursion depth exceeded while calling a Python object
I tried importing the login method with from django.contrib.auth import login as django_login as to not confuse methods, but it still did not work.
Authentication works just fine without the login method, but it doesn't save the user in the session, so it's no use.
Here is the full views.py file:
from django.utils.translation import ugettext as _
from rest_framework.permissions import AllowAny, IsAuthenticated
from rest_framework.authentication import SessionAuthentication, BasicAuthentication
from rest_framework.views import APIView
from rest_framework.response import Response
from rest.models import User
from .serializers import UserSerializer
from django.contrib.auth import get_user_model
from django.contrib.auth import authenticate as django_authenticate
from django.contrib.auth import login as django_login
from django.contrib.auth.hashers import check_password
import json
class UserCreateAPIView(generics.CreateAPIView):
queryset = User.objects.all()
serializer_class = UserSerializer
permission_classes = (AllowAny,)
class Authentication(authentication.BaseAuthentication):
def authenticate(self, request):
email = request.POST.get('email', None)
password = request.POST.get('password', None)
if not email or not password:
raise exceptions.AuthenticationFailed(_('No credentials provided.'))
credentials = {
get_user_model().USERNAME_FIELD: email,
'password': password
}
user = django_authenticate(**credentials)
if user is None:
raise exceptions.AuthenticationFailed(_('Invalid username/password.'))
if not user.is_active:
raise exceptions.AuthenticationFailed(_('User inactive or deleted.'))
django_login(request, user)
return (user, None) # authentication successful
class LoginView(APIView):
authentication_classes = (SessionAuthentication, Authentication)
permission_classes = (IsAuthenticated,)
def post(self, request, format=None):
content = {
'user': str(request.user),
'auth': str(request.auth),
}
return Response(content)
def CheckLoginView(requst):
current_user = requst.user
return current_user
Here is the traceback:
response = get_response(request) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/core/handlers/base.py in _get_response
response = self.process_exception_by_middleware(e, request) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/core/handlers/base.py in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/views/decorators/csrf.py in wrapped_view
return view_func(*args, **kwargs) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/views/generic/base.py in view
return self.dispatch(request, *args, **kwargs) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in dispatch
response = self.handle_exception(exc) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in handle_exception
self.raise_uncaught_exception(exc) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in raise_uncaught_exception
raise exc …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in dispatch
self.initial(request, *args, **kwargs) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in initial
self.perform_authentication(request) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/views.py in perform_authentication
request.user …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in user
self._authenticate() …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in _authenticate
user_auth_tuple = authenticator.authenticate(self) …
▶ Local vars
/var/www/cnmb10a/cnmb10a/rest/auth_api/views.py in authenticate
django_login(request, user) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/contrib/auth/__init__.py in login
if hasattr(request, 'user'): …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in user
self._authenticate() …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in _authenticate
user_auth_tuple = authenticator.authenticate(self) …
▶ Local vars
/var/www/cnmb10a/cnmb10a/rest/auth_api/views.py in authenticate
django_login(request, user) …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/django/contrib/auth/__init__.py in login
if hasattr(request, 'user'): …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in user
self._authenticate() …
▶ Local vars
/var/www/cnmb10a/venv/lib/python3.7/site-packages/rest_framework/request.py in _authenticate
user_auth_tuple = authenticator.authenticate(self) …
▶ Local vars
/var/www/cnmb10a/cnmb10a/rest/auth_api/views.py in authenticate
django_login(request, user) …
▶ Local vars
The last 4 methods just repeat over and over again.

Answer 1

django.contrib.auth.authenticate will call the backend to try to authenticate a user.
By calling it in your authentication backend, it will loop forever because django.contrib.auth.authenticate will be calling you backend which will call the function and so on.
So you need to hereto from the authentication method your are trying to override and call super().authenticate(request) instead of django.contrib.auth.authenticate.

Answer 2

The problem seemed to be that the django_login() function called the authenticate() that I wrote, which in turn called django_login() again.
The solution was to remove django_login() from inside authenticate() and add it to LoginView(), so it looks like this:
authentication_classes = (SessionAuthentication, Authentication)
permission_classes = (IsAuthenticated,)
def post(self, request, format=None):
content = {
'user': str(request.user),
'auth': str(request.auth),
}
django_login(request, request.user)
return Response(content)