Warn when DjangoObjectType has neither fields nor exclude option

graphene_django/tests/test_types.py

@@ -476,6 +476,37 @@ def test_django_objecttype_exclude_fields_exist_on_model():
     assert len(record) == 0
 
 
+@with_local_registry
+def test_django_objecttype_neither_fields_nor_exclude():
+    with pytest.warns(
+        PendingDeprecationWarning,
+        match=r"Creating a DjangoObjectType without either the `fields` "
+        "or the `exclude` option is deprecated.",
+    ):
+
+        class Reporter(DjangoObjectType):
+            class Meta:
+                model = ReporterModel
+
+    with pytest.warns(None) as record:
+
+        class Reporter2(DjangoObjectType):
+            class Meta:
+                model = ReporterModel
+                fields = ["email"]
+
+    assert len(record) == 0
+
+    with pytest.warns(None) as record:
+
+        class Reporter3(DjangoObjectType):
+            class Meta:
+                model = ReporterModel
+                exclude = ["email"]
+
+    assert len(record) == 0
+
+
 def custom_enum_name(field):
     return "CustomEnum{}".format(field.name.title())
 

graphene_django/types.py

@@ -220,6 +220,16 @@ class DjangoObjectType(ObjectType):
                 % type(exclude).__name__
             )
 
+        if fields is None and exclude is None:
+            warnings.warn(
+                "Creating a DjangoObjectType without either the `fields` "
+                "or the `exclude` option is deprecated. Add an explicit `fields "
+                "= '__all__'` option on DjangoObjectType {class_name} to use all "
+                "fields".format(class_name=cls.__name__,),
+                PendingDeprecationWarning,
+                stacklevel=2,
+            )
+
         django_fields = yank_fields_from_attrs(
             construct_fields(model, registry, fields, exclude, convert_choices_to_enum),
             _as=Field,