Add missing decorators: @versioning_class(), @content_negotiation_class(), @metadata_class() for function based views (#9719)

Author: qqii

docs/api-guide/views.md

@@ -186,8 +186,13 @@ The available decorators are:
 * `@authentication_classes(...)`
 * `@throttle_classes(...)`
 * `@permission_classes(...)`
+* `@content_negotiation_class(...)`
+* `@metadata_class(...)`
+* `@versioning_class(...)`
 
-Each of these decorators takes a single argument which must be a list or tuple of classes.
+Each of these decorators is equivalent to setting their respective [api policy attributes][api-policy-attributes].
+
+All decorators take a single argument. The ones that end with `_class` expect a single class while the ones ending in `_classes` expect a list or tuple of classes.
 
 
 ## View schema decorator
@@ -224,4 +229,5 @@ You may pass `None` in order to exclude the view from schema generation.
 [throttling]: throttling.md
 [schemas]: schemas.md
 [classy-drf]: http://www.cdrf.co
+[api-policy-attributes]: views.md#api-policy-attributes
 

rest_framework/decorators.py

@@ -70,6 +70,15 @@ def handler(self, *args, **kwargs):
         WrappedAPIView.permission_classes = getattr(func, 'permission_classes',
                                                     APIView.permission_classes)
 
+        WrappedAPIView.content_negotiation_class = getattr(func, 'content_negotiation_class',
+                                                           APIView.content_negotiation_class)
+
+        WrappedAPIView.metadata_class = getattr(func, 'metadata_class',
+                                                APIView.metadata_class)
+
+        WrappedAPIView.versioning_class = getattr(func, "versioning_class",
+                                                  APIView.versioning_class)
+
         WrappedAPIView.schema = getattr(func, 'schema',
                                         APIView.schema)
 
@@ -113,6 +122,27 @@ def decorator(func):
     return decorator
 
 
+def content_negotiation_class(content_negotiation_class):
+    def decorator(func):
+        func.content_negotiation_class = content_negotiation_class
+        return func
+    return decorator
+
+
+def metadata_class(metadata_class):
+    def decorator(func):
+        func.metadata_class = metadata_class
+        return func
+    return decorator
+
+
+def versioning_class(versioning_class):
+    def decorator(func):
+        func.versioning_class = versioning_class
+        return func
+    return decorator
+
+
 def schema(view_inspector):
     def decorator(func):
         func.schema = view_inspector

tests/test_decorators.py

@@ -6,16 +6,19 @@
 from rest_framework import status
 from rest_framework.authentication import BasicAuthentication
 from rest_framework.decorators import (
-    action, api_view, authentication_classes, parser_classes,
-    permission_classes, renderer_classes, schema, throttle_classes
+    action, api_view, authentication_classes, content_negotiation_class,
+    metadata_class, parser_classes, permission_classes, renderer_classes,
+    schema, throttle_classes, versioning_class
 )
+from rest_framework.negotiation import BaseContentNegotiation
 from rest_framework.parsers import JSONParser
 from rest_framework.permissions import IsAuthenticated
 from rest_framework.renderers import JSONRenderer
 from rest_framework.response import Response
 from rest_framework.schemas import AutoSchema
 from rest_framework.test import APIRequestFactory
 from rest_framework.throttling import UserRateThrottle
+from rest_framework.versioning import QueryParameterVersioning
 from rest_framework.views import APIView
 
 
@@ -150,6 +153,43 @@ def view(request):
         response = view(request)
         assert response.status_code == status.HTTP_429_TOO_MANY_REQUESTS
 
+    def test_versioning_class(self):
+        @api_view(["GET"])
+        @versioning_class(QueryParameterVersioning)
+        def view(request):
+            return Response({"version": request.version})
+
+        request = self.factory.get("/?version=1.2.3")
+        response = view(request)
+        assert response.data == {"version": "1.2.3"}
+
+    def test_metadata_class(self):
+        # From TestMetadata.test_none_metadata()
+        @api_view()
+        @metadata_class(None)
+        def view(request):
+            return Response({})
+
+        request = self.factory.options('/')
+        response = view(request)
+        assert response.status_code == status.HTTP_405_METHOD_NOT_ALLOWED
+        assert response.data == {'detail': 'Method "OPTIONS" not allowed.'}
+
+    def test_content_negotiation(self):
+        class CustomContentNegotiation(BaseContentNegotiation):
+            def select_renderer(self, request, renderers, format_suffix):
+                assert request.META['HTTP_ACCEPT'] == 'custom/type'
+                return (renderers[0], renderers[0].media_type)
+
+        @api_view(["GET"])
+        @content_negotiation_class(CustomContentNegotiation)
+        def view(request):
+            return Response({})
+
+        request = self.factory.get('/', HTTP_ACCEPT='custom/type')
+        response = view(request)
+        assert response.status_code == status.HTTP_200_OK
+
     def test_schema(self):
         """
         Checks CustomSchema class is set on view