Fixed filterset limit issue

Author: syrusakbary

graphene_django/fields.py

@@ -46,18 +46,21 @@ def get_manager(self):
         else:
             return self.model._default_manager
 
-    @staticmethod
-    def connection_resolver(resolver, connection, default_manager, root, args, context, info):
+    @classmethod
+    def merge_querysets(cls, default_queryset, queryset):
+        return default_queryset & queryset
+
+    @classmethod
+    def connection_resolver(cls, resolver, connection, default_manager, root, args, context, info):
         iterable = resolver(root, args, context, info)
         if iterable is None:
             iterable = default_manager
         iterable = maybe_queryset(iterable)
         if isinstance(iterable, QuerySet):
             if iterable is not default_manager:
-                iterable = list(set(iterable).intersection(maybe_queryset(default_manager)))
-                _len = len(iterable)
-            else:
-                _len = iterable.count()
+                default_queryset = maybe_queryset(default_manager)
+                iterable = cls.merge_querysets(default_queryset, iterable)
+            _len = iterable.count()
         else:
             _len = len(iterable)
         connection = connection_from_list_slice(

graphene_django/filter/fields.py

@@ -45,14 +45,37 @@ def filtering_args(self):
         return get_filtering_args_from_filterset(self.filterset_class, self.node_type)
 
     @staticmethod
-    def connection_resolver(resolver, connection, default_manager, filterset_class, filtering_args,
+    def merge_querysets(default_queryset, queryset):
+        # There could be the case where the default queryset (returned from the filterclass)
+        # and the resolver queryset have some limits on it.
+        # We only would be able to apply one of those, but not both
+        # at the same time.
+
+        # See related PR: https://github.com/graphql-python/graphene-django/pull/126
+
+        assert not (default_queryset.query.low_mark and queryset.query.low_mark), (
+            'Received two sliced querysets (low mark) in the connection, please slice only in one.'
+        )
+        assert not (default_queryset.query.high_mark and queryset.query.high_mark), (
+            'Received two sliced querysets (high mark) in the connection, please slice only in one.'
+        )
+        low = default_queryset.query.low_mark or queryset.query.low_mark
+        high = default_queryset.query.high_mark or queryset.query.high_mark
+        default_queryset.query.clear_limits()
+        queryset = default_queryset & queryset
+        queryset.query.set_limits(low, high)
+        return queryset
+
+    @classmethod
+    def connection_resolver(cls, resolver, connection, default_manager, filterset_class, filtering_args,
                             root, args, context, info):
         filter_kwargs = {k: v for k, v in args.items() if k in filtering_args}
         qs = filterset_class(
             data=filter_kwargs,
             queryset=default_manager.get_queryset()
         ).qs
-        return DjangoConnectionField.connection_resolver(resolver, connection, qs, root, args, context, info)
+        return super(DjangoFilterConnectionField, cls).connection_resolver(
+            resolver, connection, qs, root, args, context, info)
 
     def get_resolver(self, parent_resolver):
         return partial(self.connection_resolver, parent_resolver, self.type, self.get_manager(),

graphene_django/tests/test_query.py

@@ -525,10 +525,12 @@ def resolve_all_reporters(self, args, context, info):
                 edges {
                     node {
                         id
+                        firstName
                         articles(lang: "es") {
                             edges {
                                 node {
                                     id
+                                    lang
                                 }
                             }
                         }
@@ -542,11 +544,13 @@ def resolve_all_reporters(self, args, context, info):
         'allReporters': {
             'edges': [{
                 'node': {
-                    'id': 'UmVwb3J0ZXJUeXBlOjE=',
+                    'id': 'UmVwb3J0ZXJUeXBlOjI=',
+                    'firstName': 'John',
                     'articles': {
                         'edges': [{
                             'node': {
-                                'id': 'QXJ0aWNsZVR5cGU6MQ=='
+                                'id': 'QXJ0aWNsZVR5cGU6MQ==',
+                                'lang': 'ES'
                             }
                         }]
                     }
@@ -558,3 +562,63 @@ def resolve_all_reporters(self, args, context, info):
     result = schema.execute(query)
     assert not result.errors
     assert result.data == expected
+
+
+def test_should_query_filter_node_double_limit_raises():
+    class ReporterFilter(FilterSet):
+        limit = NumberFilter(method='filter_limit')
+
+        def filter_limit(self, queryset, name, value):
+            return queryset[:value]
+
+        class Meta:
+            model = Reporter
+            fields = ['first_name', ]
+
+    class ReporterType(DjangoObjectType):
+
+        class Meta:
+            model = Reporter
+            interfaces = (Node, )
+
+    class Query(graphene.ObjectType):
+        all_reporters = DjangoFilterConnectionField(
+            ReporterType,
+            filterset_class=ReporterFilter
+        )
+
+        def resolve_all_reporters(self, args, context, info):
+            return Reporter.objects.order_by('a_choice')[:2]
+
+    Reporter.objects.create(
+        first_name='Bob',
+        last_name='Doe',
+        email='bobdoe@example.com',
+        a_choice=2
+    )
+    r = Reporter.objects.create(
+        first_name='John',
+        last_name='Doe',
+        email='johndoe@example.com',
+        a_choice=1
+    )
+
+    schema = graphene.Schema(query=Query)
+    query = '''
+        query NodeFilteringQuery {
+            allReporters(limit: 1) {
+                edges {
+                    node {
+                        id
+                        firstName
+                    }
+                }
+            }
+        }
+    '''
+
+    result = schema.execute(query)
+    assert len(result.errors) == 1
+    assert str(result.errors[0]) == (
+        'Received two sliced querysets (high mark) in the connection, please slice only in one.'
+    )