allow_empty -> pending deprecation in preference of overridden get_queryset.

docs/api-guide/generic-views.md

@@ -75,10 +75,9 @@ The following attibutes are used to control pagination when used with list views
 * `pagination_serializer_class` - The pagination serializer class to use when determining the style of paginated responses.  Defaults to the same value as the `DEFAULT_PAGINATION_SERIALIZER_CLASS` setting.
 * `page_kwarg` - The name of a URL kwarg or URL query parameter which can be used by the client to control which page is requested.  Defaults to `'page'`.
 
-**Other**:
+**Filtering**:
 
 * `filter_backend` - The filter backend class that should be used for filtering the queryset.  Defaults to the same value as the `FILTER_BACKEND` setting.
-* `allow_empty` - Determines if an empty list should successfully display zero results, or return a 404 response.  Defaults to `True`, meaning empty lists will return sucessful `200 OK` responses, with zero results.
 
 ### Methods
 

docs/topics/2.3-announcement.md

@@ -152,9 +152,21 @@ And would have the following entry in the urlconf:
 
      url(r'^users/(?P<username>\w+)/$', UserDetail.as_view()),
 
-
 Usage of the old-style attributes continues to be supported, but will raise a `PendingDeprecationWarning`.
 
+The `allow_empty` attribute is also deprecated.  To use `allow_empty=False` style behavior you should explicitly override `get_queryset` and raise an `Http404` on empty querysets.
+
+For example:
+
+    class DisallowEmptyQuerysetMixin(object):
+        def get_queryset(self):
+            queryset = super(DisallowEmptyQuerysetMixin, self).get_queryset()
+            if not queryset.exists():
+                raise Http404
+            return queryset
+
+In our opinion removing lesser-used attributes like `allow_empty` helps us move towards simpler generic view implementations, making them more obvious to use and override, and re-inforcing the preferred style of developers writing their own base classes and mixins for custom behavior rather than relying on the configurability of the generic views.
+
 ## Simpler URL lookups
 
 The `HyperlinkedRelatedField` class now takes a single optional `lookup_field` argument, that replaces the `pk_url_kwarg`, `slug_url_kwarg`, and `slug_field` arguments.

rest_framework/filters.py

@@ -3,7 +3,10 @@ Provides generic filtering backends that can be used to filter the results
 returned by list views.
 """
 from __future__ import unicode_literals
+
+from django.db import models
 from rest_framework.compat import django_filters
+import operator
 
 FilterSet = django_filters and django_filters.FilterSet or None
 
@@ -62,3 +65,29 @@ class DjangoFilterBackend(BaseFilterBackend):
             return filter_class(request.QUERY_PARAMS, queryset=queryset).qs
 
         return queryset
+
+
+class SearchFilter(BaseFilterBackend):
+    def construct_search(self, field_name):
+        if field_name.startswith('^'):
+            return "%s__istartswith" % field_name[1:]
+        elif field_name.startswith('='):
+            return "%s__iexact" % field_name[1:]
+        elif field_name.startswith('@'):
+            return "%s__search" % field_name[1:]
+        else:
+            return "%s__icontains" % field_name
+
+    def filter_queryset(self, request, queryset, view):
+        search_fields = getattr(view, 'search_fields', None)
+
+        if not search_fields:
+            return None
+
+        orm_lookups = [self.construct_search(str(search_field))
+                       for search_field in self.search_fields]
+        for bit in self.query.split():
+            or_queries = [models.Q(**{orm_lookup: bit})
+                          for orm_lookup in orm_lookups]
+            queryset = queryset.filter(reduce(operator.or_, or_queries))
+        return queryset

rest_framework/generics.py

@@ -42,9 +42,6 @@ class GenericAPIView(views.APIView):
     # The filter backend class to use for queryset filtering
     filter_backend = api_settings.FILTER_BACKEND
 
-    # Determines if the view will return 200 or 404 responses for empty lists.
-    allow_empty = True
-
     # The following attributes may be subject to change,
     # and should be considered private API.
     model_serializer_class = api_settings.DEFAULT_MODEL_SERIALIZER_CLASS
@@ -56,6 +53,7 @@ class GenericAPIView(views.APIView):
     pk_url_kwarg = 'pk'
     slug_url_kwarg = 'slug'
     slug_field = 'slug'
+    allow_empty = True
 
     def get_serializer_context(self):
         """
@@ -111,6 +109,14 @@ class GenericAPIView(views.APIView):
             if not page_size:
                 return None
 
+        if not self.allow_empty:
+            warnings.warn(
+                'The `allow_empty` parameter is due to be deprecated. '
+                'To use `allow_empty=False` style behavior, You should override '
+                '`get_queryset()` and explicitly raise a 404 on empty querysets.',
+                PendingDeprecationWarning, stacklevel=2
+            )
+
         paginator = self.paginator_class(queryset, page_size,
                                          allow_empty_first_page=self.allow_empty)
         page_kwarg = self.kwargs.get(self.page_kwarg)