views.py

def viewset_factory(*, name: str, method_mapping: Mapping, viewset_class=viewsets.GenericViewSet, **attrs):
    """Returns ViewSet class with views' methods got from `method_mapping`

    Example:

        Suppose, we have 2 views:
            FooListView(generics.ListAPIView):
                def list(request):
                    # impl.
                    pass

            FooCreateView(generics.CreateAPIView):
                def create(request:
                    # impl.
                    pass

        And we want to combine them into one viewset to make possible
        passsing it to the `rest_framework` router

        FooViewSet = viewset_factory(
            name='FooViewSet',
            method_mapping={
                'list': FooListView,
                'create': FooCreateView,
            }
        )

        This is roughly equivalent to:

        class FooViewSet(viewsets.GenericViewSet):
            def list(self, request, *args, **kwargs):
                view_class = FooListView(request=request)
                view_class.args = args
                view_class.kwargs = kwargs
                view_class.initial(request)
                return view_class.list(request)

            def create(self, request):
                view_class = FooCreateView(request=request)
                view_class.args = args
                view_class.kwargs = kwargs
                view_class.initial(request)
                return view_class.create(request)

    """

    def _create_viewset_method(view_class, method):
        def _method(cls, request, *args, **kwargs):
            view = view_class(request=request)
            view.args = args
            view.kwargs = kwargs
            view.initial(request)
            m = getattr(view, method)
            return m(request, *args, **kwargs)

        return _method

    def _get_serializer_class(viewset):
        requested_class = method_mapping[viewset.action]
        return requested_class.serializer_class

    viewset_class_name, viewset_class_attrs = name, {}

    for method, view_class in method_mapping.items():
        view_method = _create_viewset_method(view_class, method)
        viewset_class_attrs[method] = view_method

    # stubs for api-docs
    attrs.setdefault('queryset', QuerySet().none())
    attrs.setdefault('get_serializer_class', _get_serializer_class)

    viewset_class_attrs.update(attrs)

    viewset = type(viewset_class)(viewset_class_name, (viewset_class,), viewset_class_attrs)
    return viewset