add default viewsets

{{cookiecutter.project_slug}}/src/app/api/viewsets.py

@@ -0,0 +1,177 @@
+from typing import Any, Optional, Protocol, Type
+
+from rest_framework import mixins
+from rest_framework import status
+from rest_framework.mixins import CreateModelMixin
+from rest_framework.mixins import UpdateModelMixin
+from rest_framework.request import Request
+from rest_framework.response import Response
+from rest_framework.serializers import BaseSerializer
+from rest_framework.viewsets import GenericViewSet
+
+__all__ = ["DefaultModelViewSet"]
+
+
+class BaseGenericViewSet(Protocol):
+    def get_serializer(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def get_response(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def perform_create(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def perform_update(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def get_success_headers(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def get_serializer_class(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+    def get_object(self, *args: Any, **kwargs: Any) -> Any:
+        ...
+
+
+class DefaultCreateModelMixin(CreateModelMixin):
+    """Return detail-serialized created instance"""
+
+    def create(self: BaseGenericViewSet, request: Request, *args: Any, **kwargs: Any) -> Response:
+        serializer = self.get_serializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        instance = self.perform_create(serializer)  # No getting created instance in original DRF
+        headers = self.get_success_headers(serializer.data)
+        return self.get_response(instance, status.HTTP_201_CREATED, headers)
+
+    def perform_create(self: BaseGenericViewSet, serializer: Any) -> Any:
+        return serializer.save()  # No returning created instance in original DRF
+
+
+class DefaultUpdateModelMixin(UpdateModelMixin):
+    """Return detail-serialized updated instance"""
+
+    def update(self: BaseGenericViewSet, request: Request, *args: Any, **kwargs: Any) -> Response:
+        partial = kwargs.pop("partial", False)
+        instance = self.get_object()
+        serializer = self.get_serializer(instance, data=request.data, partial=partial)
+        serializer.is_valid(raise_exception=True)
+        instance = self.perform_update(serializer)  # No getting updated instance in original DRF
+
+        if getattr(instance, "_prefetched_objects_cache", None):
+            # If 'prefetch_related' has been applied to a queryset, we need to
+            # forcibly invalidate the prefetch cache on the instance.
+            instance._prefetched_objects_cache = {}
+
+        return self.get_response(instance, status.HTTP_200_OK)
+
+    def perform_update(self: BaseGenericViewSet, serializer: Any) -> Any:
+        return serializer.save()  # No returning updated instance in original DRF
+
+
+class ResponseWithRetrieveSerializerMixin:
+    """
+    Always response with 'retrieve' serializer or fallback to `serializer_class`.
+    Usage:
+
+    class MyViewSet(DefaultModelViewSet):
+        serializer_class = MyDefaultSerializer
+        serializer_action_classes = {
+           'list': MyListSerializer,
+           'my_action': MyActionSerializer,
+        }
+        @action
+        def my_action:
+            ...
+
+    'my_action' request will be validated with MyActionSerializer,
+    but response will be serialized with MyDefaultSerializer
+    (or 'retrieve' if provided).
+
+    Thanks gonz: http://stackoverflow.com/a/22922156/11440
+
+    """
+
+    def get_response(
+        self: BaseGenericViewSet,
+        instance: Any,
+        status: Any,
+        headers: Any = None,
+    ) -> Response:
+        retrieve_serializer_class = self.get_serializer_class(action="retrieve")
+        context = self.get_serializer_context()  # type: ignore
+        retrieve_serializer = retrieve_serializer_class(instance, context=context)
+        return Response(
+            retrieve_serializer.data,
+            status=status,
+            headers=headers,
+        )
+
+    def get_serializer_class(
+        self: BaseGenericViewSet,
+        action: Optional[str] = None,
+    ) -> Type[BaseSerializer]:
+        if action is None:
+            action = self.action  # type: ignore
+
+        try:
+            return self.serializer_action_classes[action]  # type: ignore
+        except (KeyError, AttributeError):
+            return super().get_serializer_class()  # type: ignore
+
+
+class DefaultModelViewSet(
+    DefaultCreateModelMixin,  # Create response is overriden
+    mixins.RetrieveModelMixin,
+    DefaultUpdateModelMixin,  # Update response is overriden
+    mixins.DestroyModelMixin,
+    mixins.ListModelMixin,
+    ResponseWithRetrieveSerializerMixin,  # Response with retrieve or default serializer
+    GenericViewSet,
+):
+    pass
+
+
+class ReadonlyModelViewSet(
+    mixins.RetrieveModelMixin,
+    mixins.ListModelMixin,
+    ResponseWithRetrieveSerializerMixin,  # Response with retrieve or default serializer
+    GenericViewSet,
+):
+    pass
+
+
+class ListOnlyModelViewSet(
+    mixins.ListModelMixin,
+    ResponseWithRetrieveSerializerMixin,  # Response with retrieve or default serializer
+    GenericViewSet,
+):
+    pass
+
+
+class UpdateOnlyModelViewSet(
+    DefaultUpdateModelMixin,
+    ResponseWithRetrieveSerializerMixin,
+    GenericViewSet,
+):
+    pass
+
+
+class DefaultRetrieveDestroyListViewSet(
+    mixins.RetrieveModelMixin,
+    mixins.DestroyModelMixin,
+    mixins.ListModelMixin,
+    ResponseWithRetrieveSerializerMixin,  # Response with retrieve or default serializer
+    GenericViewSet,
+):
+    pass
+
+
+class ListUpdateModelViewSet(
+    DefaultUpdateModelMixin,
+    mixins.ListModelMixin,
+    ResponseWithRetrieveSerializerMixin,
+    GenericViewSet,
+):
+    pass