Django Rest Framework remove csrf

Question

I know that there are answers regarding Django Rest Framework, but I couldn't find a solution to my problem.

I have an application which has authentication and some functionality. I added a new app to it, which uses Django Rest Framework. I want to use the library only in this app. Also I want to make POST request, and I always receive this response:

{
    "detail": "CSRF Failed: CSRF token missing or incorrect."
}

I have the following code:

# urls.py
from django.conf.urls import patterns, url


urlpatterns = patterns(
    'api.views',
    url(r'^object/$', views.Object.as_view()),
)

# views.py
from rest_framework.views import APIView
from rest_framework.response import Response
from django.views.decorators.csrf import csrf_exempt


class Object(APIView):

    @csrf_exempt
    def post(self, request, format=None):
        return Response({'received data': request.data})

I want add the API without affecting the current application. So my questions is how can I disable CSRF only for this app ?

Answer 1

Why this error is happening?

This is happening because of the default SessionAuthentication scheme used by DRF. DRF's SessionAuthentication uses Django's session framework for authentication which requires CSRF to be checked.

When you don't define any authentication_classes in your view/viewset, DRF uses this authentication classes as the default.

'DEFAULT_AUTHENTICATION_CLASSES'= (
    'rest_framework.authentication.SessionAuthentication',
    'rest_framework.authentication.BasicAuthentication'
),

Since DRF needs to support both session and non-session based authentication to the same views, it enforces CSRF check for only authenticated users. This means that only authenticated requests require CSRF tokens and anonymous requests may be sent without CSRF tokens.

If you're using an AJAX style API with SessionAuthentication, you'll need to include a valid CSRF token for any "unsafe" HTTP method calls, such as PUT, PATCH, POST or DELETE requests.

What to do then?

Now to disable csrf check, you can create a custom authentication class CsrfExemptSessionAuthentication which extends from the default SessionAuthentication class. In this authentication class, we will override the enforce_csrf() check which was happening inside the actual SessionAuthentication.

from rest_framework.authentication import SessionAuthentication, BasicAuthentication 

class CsrfExemptSessionAuthentication(SessionAuthentication):

    def enforce_csrf(self, request):
        return  # To not perform the csrf check previously happening

In your view, then you can define the authentication_classes to be:

authentication_classes = (CsrfExemptSessionAuthentication, BasicAuthentication)

This should handle the csrf error.

Answer 2

Easier solution:

In views.py, use braces CsrfExemptMixin and authentication_classes:

# views.py
from rest_framework.views import APIView
from rest_framework.response import Response
from django.views.decorators.csrf import csrf_exempt
from braces.views import CsrfExemptMixin


class Object(CsrfExemptMixin, APIView):
    authentication_classes = []

    def post(self, request, format=None):
        return Response({'received data': request.data})

Answer 3

Modify urls.py

If you manage your routes in urls.py, you can wrap your desired routes with csrf_exempt() to exclude them from the CSRF verification middleware.

from django.conf.urls import patterns, url
    from django.views.decorators.csrf import csrf_exempt
    import views

urlpatterns = patterns('',
    url(r'^object/$', csrf_exempt(views.ObjectView.as_view())),
    ...
)

Alternatively, as a Decorator Some may find the use of the @csrf_exempt decorator more suitable for their needs

for instance,

from django.views.decorators.csrf import csrf_exempt
from django.http import HttpResponse

@csrf_exempt
def my_view(request):
    return HttpResponse('Hello world')

should get the Job Done!

Answer 4

If you do not want to use session based authentication, you can remove Session Authentication from REST_AUTHENTICATION_CLASSES and that would automatically remove all csrf based issues. But in that case Browseable apis might not work.

Besides this error should not come even with session authentication. You should use custom authentication like TokenAuthentication for your apis and make sure to send Accept:application/json and Content-Type:application/json(provided you are using json) in your requests along with authentication token.

Answer 5

For all who did not find a helpful answer. Yes DRF automatically removes CSRF protection if you do not use SessionAuthentication AUTHENTICATION CLASS, for example, many developers use only JWT:

'DEFAULT_AUTHENTICATION_CLASSES': (
        'rest_framework_jwt.authentication.JSONWebTokenAuthentication',
    ),

But issue CSRF not set may be occurred from some another reason, for exmple you not correctly added path to you view:

url(r'^api/signup/', CreateUserView),  # <= error! DRF cant remove CSRF because it is not as_view that does it!

instead of

url(r'^api/signup/', CreateUserView.as_view()),

Answer 6

I am struck with the same problem. I followed this reference and it worked. Solution is to create a middleware

Add disable.py file in one of your apps (in my case it is 'myapp')

class DisableCSRF(object):
    def process_request(self, request):
        setattr(request, '_dont_enforce_csrf_checks', True)

And add the middileware to the MIDDLEWARE_CLASSES

MIDDLEWARE_CLASSES = (
myapp.disable.DisableCSRF,
)

Answer 7

If you are using an exclusive virtual environment for your application, you can use the following approach without effective any other applications.

What you observed happens because rest_framework/authentication.py has this code in the authenticate method of SessionAuthentication class:

self.enforce_csrf(request)

You can modify the Request class to have a property called csrf_exempt and initialize it inside your respective View class to True if you do not want CSRF checks. For example:

Next, modify the above code as follows:

if not request.csrf_exempt:
    self.enforce_csrf(request)

There are some related changes you'd have to do it in the Request class. A complete implementation is available here (with full description): https://github.com/piaxis/django-rest-framework/commit/1bdb872bac5345202e2f58728d0e7fad70dfd7ed

Answer 8

My Solution is shown blow. Just decorate my class.

from django.views.decorators.csrf import csrf_exempt
@method_decorator(csrf_exempt, name='dispatch')
@method_decorator(basic_auth_required(
    target_test=lambda request: not request.user.is_authenticated
), name='dispatch')
class GenPedigreeView(View):
    pass

Answer 9

I tried a few of the answers above and felt creating a separate class was a little overboard.

For reference, I ran into this problem when trying to update a function based view method to a class based view method for user registration.

When using class-based-views (CBVs) and Django Rest Framework (DRF), Inherit from the ApiView class and set permission_classes and authentication_classes to an empty tuple. Find an example below.

class UserRegistrationView(APIView):

    permission_classes = ()
    authentication_classes = ()

    def post(self, request, *args, **kwargs):

        # rest of your code here

Answer 10

This could also be a problem during a DNS Rebinding attack.

In between DNS changes, this can also be a factor. Waiting till DNS is fully flushed will resolve this if it was working before DNS problems/changes.