Django-rest-framework: Not sure if 'lookup_url_kwarg' works for generic views

[atikbappy]

get_object() method of GenericAPIView class (rest_framework/generics.py line: 88-98)

        lookup_url_kwarg = self.lookup_url_kwarg or self.lookup_field

        assert lookup_url_kwarg in self.kwargs, (
            'Expected view %s to be called with a URL keyword argument '
            'named "%s". Fix your URL conf, or set the `.lookup_field` '
            'attribute on the view correctly.' %
            (self.__class__.__name__, lookup_url_kwarg)
        )

        filter_kwargs = {self.lookup_field: self.kwargs[lookup_url_kwarg]}
        obj = get_object_or_404(queryset, **filter_kwargs)

Since we are using self.lookup_field as keyword argument for filtering so self.lookup_url_kwarg doesn't have any use case as we are not using it for keyword argument.

filter_kwargs = {self.lookup_field: self.kwargs[lookup_url_kwarg]}

For example: lookup_url_kwarg = 'slug' doesn't work

---

Edited for formatting (@rpkilby)

[rpkilby]

Hi @atikbappy.

• self.lookup_field defines what model field is used when querying the object.
• self.lookup_url_kwarg defines what URL kwarg to get from the view's initialized kwargs.

Often these two values are the same, so the local lookup_url_kwarg will default to self.lookup_field if self.lookup_url_kwarg is not defined.

If you've only provided self.lookup_url_kwarg, then the query will look like .filter(pk='some-slug'), when you're probably looking for .filter(slug='some-slug'). You need to set the lookup_field. eg,

class MyView(GenericAPIView):
    lookup_field = 'slug'