Improve viewset action docs

[k0t3n]

Hi,
I encountered a problem when overriding viewset-level attributes doesn't work for actions if a route is configured as .as_view().

Example:

# views.py
class TestView(viewsets.ModelViewSet):
    @action(methods=['get'], detail=False, url_name='test_action', permission_classes=[IsAuthenticated,])
    def test_action(self, request):
        return Response()

# urls.py
urlpatterns = [
    path('test_urlpattern/', TestViewSet.as_view({'get': 'test_action'},)),
]

# tests.py
@pytest.mark.django_db
def test_case(client):
    url = reverse('test_urlpattern')
    response = client.get(url)
    assert response.status_code == 200  # expected 401!

You can override it using initkwargs only

# urls.py
urlpatterns = [
    # permission will be added
    path('test_urlpattern/', TestViewSet.as_view({'get': 'test_action'}, permission_classes=[IsAuthenticated, ])),
]

According to the docs, it's not clear this feature works for Router configuration only. No exceptions, warnings, or even related github issues were found regarding this.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[auvipy]

isn't .as_view only work for class based views only? do we need this in viewsets?

[k0t3n]

isn't .as_view only work for class based views only? do we need this in viewsets?

If your question is whether the drf needs .as_view() in view sets, I believe yes, at least because lots of users' code may rely on it. My suggestion is to add some sort of validation or warning on passing arguments to .as_view(), since if you try to reroute GET requests to a specific function (action) the requests would just be passed to the default get() handler no matter what you configured before.