diff options
Diffstat (limited to 'rest_framework/generics.py')
| -rw-r--r-- | rest_framework/generics.py | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/rest_framework/generics.py b/rest_framework/generics.py index e38c52b1..cecb548f 100644 --- a/rest_framework/generics.py +++ b/rest_framework/generics.py @@ -43,6 +43,10 @@ class GenericAPIView(views.APIView): # You'll need to either set these attributes, # or override `get_queryset()`/`get_serializer_class()`. + # If you are overriding a view method, it is important that you call + # `get_queryset()` instead of accessing the `queryset` property directly, + # as `queryset` will get evaluated only once, and those results are cached + # for all subsequent requests. queryset = None serializer_class = None @@ -185,7 +189,13 @@ class GenericAPIView(views.APIView): """ Returns the list of filter backends that this view requires. """ - filter_backends = self.filter_backends or [] + if self.filter_backends is None: + filter_backends = [] + else: + # Note that we are returning a *copy* of the class attribute, + # so that it is safe for the view to mutate it if needed. + filter_backends = list(self.filter_backends) + if not filter_backends and self.filter_backend: warnings.warn( 'The `filter_backend` attribute and `FILTER_BACKEND` setting ' @@ -195,6 +205,7 @@ class GenericAPIView(views.APIView): DeprecationWarning, stacklevel=2 ) filter_backends = [self.filter_backend] + return filter_backends @@ -258,6 +269,10 @@ class GenericAPIView(views.APIView): This must be an iterable, and may be a queryset. Defaults to using `self.queryset`. + This method should always be used rather than accessing `self.queryset` + directly, as `self.queryset` gets evaluated only once, and those results + are cached for all subsequent requests. + You may want to override this if you need to provide different querysets depending on the incoming request. |