Nesting ViewSet routes in DRF

Question

I've created 2 ModelViewSets like so (simplified for demonstration):

class SomeBaseViewSet(viewsets.ReadOnlyModelViewSet):
    serializer_class = SomeEventSerializer
    permission_classes = (permissions.IsAuthenticated,)

    def get_queryset(self):
        return SomeObjects.objects.filter(owner=self.request.user)

    def get_serializer_context(self):
        context = super(SomeBaseViewSet, self).get_serializer_context()
        context.update({
            "user": self.request.user,
            "some_context_key": False
        })
        return context

class AdminViewSet(SomeBaseViewSet):
    # Added in the HasAdminPermission
    permission_classes = (permissions.IsAuthenticated, HasAdminPermission)

    # Different queryset filter (overriding `get_queryset` vs setting queryset for standardization)
    def get_queryset(self):
        return SomeObjects.objects.all()

    # The context should have `some_context_key=True`, and `user=request.user`
    def get_serializer_context(self):
        context = super(AdminViewSet, self).get_serializer_context()
        context.update({
            "some_context_key": True
        })
        return context

My router/url config looks like this

router = DefaultRouter()

router.register(r'some_view', SomeBaseViewSet, base_name="some_view")

urlpatterns += [
    url(r'^api/', include(router.urls)),
]

If I wanted to route /api/some_view/admin to the AdminViewSet, what's the best way to do that?

Things I've tried:

• @list_route on SomeBaseViewSet, but couldn't figure out the "right" way to wire it to my AdminViewSet
• Adding url(r'^api/some_view/admin$', AdminViewSet.as_view({"get": "list"})) to my urlpatterns (which sorta works but neuters the ViewSet a bit, and is generally really manual anyway):
• Having a dedicated DefaultRouter for the some_view viewset, which I then mount on url(r'^api/some_view/') - again hacky and pedantic to do with a large number of routes

Is there a "right" way to do what I'm trying to accomplish, or should I reach for a different solution to this problem (i.e. a filter or something)?

I've seen libraries like https://github.com/alanjds/drf-nested-routers, but that seems like overkill for my (fairly simple) needs.

Answer 1

Define your admin viewset using a list route. These params will allow you to perform a get request, with specified permissions(is authenticated and has admin perms), that extends this class. ie /someview/admin or someotherview/admin

from rest_framework.decorators import list_route
class AdminViewSet(viewset.Viewsets):

    @list_route(methods=['get'], 
                  permissions=[permissions.IsAuthenticated, HasAdminPermission],
                  url_path='admin'
     )
     def admin(self, request):
          # All your custom logic in regards to querysets and serializing
          return serialized.data

Then you can extend your any viewset that needs an admin action route.

class SomeBaseViewSet(viewsets.ReadOnlyModelViewSet, AdminViewset):
    serializer_class = SomeEventSerializer
    permission_classes = (permissions.IsAuthenticated,)

    def get_queryset(self):
        return SomeObjects.objects.filter(owner=self.request.user)

    def get_serializer_context(self):
        context = super(SomeBaseViewSet, self).get_serializer_context()
        context.update({
            "user": self.request.user,
            "some_context_key": False
        })
        return context

You want to be careful with this because typically the param after your base route ie /someview/{param}/ is reserved for ID references. Make sure your id reference will not conflict with your detail route.