objects.base: avoid db access if object does not have changes

Also cover base object with unit tests.

Change-Id: I2f58c767ba35eeee2f9ecc363e5b042ea8638faa

diff --git a/neutron/objects/base.py b/neutron/objects/base.py
index b7198692e4732ad81cef56bc5775177b61ac4b16..57f785ea41fc24b845a51d40e1b48b72df77476d 100644 (file)
--- a/neutron/objects/base.py
+++ b/neutron/objects/base.py
@@ -54,9 +54,10 @@ class NeutronObject(obj_base.VersionedObject,
 
     def update(self):
         updates = self.obj_get_changes()
-        db_obj = db_api.update_object(self._context, self.db_model,
-                                      self.id, updates)
-        self.from_db_object(self, db_obj)
+        if updates:
+            db_obj = db_api.update_object(self._context, self.db_model,
+                                          self.id, updates)
+            self.from_db_object(self, db_obj)
 
     def delete(self):
         db_api.delete_object(self._context, self.db_model, self.id)

diff --git a/neutron/tests/unit/objects/__init__.py b/neutron/tests/unit/objects/__init__.py
new file mode 100644 (file)
index 0000000..e69de29

diff --git a/neutron/tests/unit/objects/test_base.py b/neutron/tests/unit/objects/test_base.py
new file mode 100644 (file)
index 0000000..49ab6b1
--- /dev/null
+++ b/neutron/tests/unit/objects/test_base.py
@@ -0,0 +1,131 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import mock
+from oslo_versionedobjects import base as obj_base
+from oslo_versionedobjects import fields as obj_fields
+
+from neutron import context
+from neutron.db import api as db_api
+from neutron.objects import base
+from neutron.tests import base as test_base
+
+
+@obj_base.VersionedObjectRegistry.register
+class FakeNeutronObject(base.NeutronObject):
+
+    db_model = 'fake_model'
+
+    fields = {
+        'id': obj_fields.UUIDField(),
+        'field1': obj_fields.StringField(),
+        'field2': obj_fields.StringField()
+    }
+
+
+db_objs = ({'id': 'id1', 'field1': 'value1', 'field2': 'value2'},
+           {'id': 'id2', 'field1': 'value3', 'field2': 'value4'},
+           {'id': 'id3', 'field1': 'value5', 'field2': 'value6'})
+db_obj = db_objs[0]
+
+
+def get_obj_fields(obj):
+    return {field: getattr(obj, field) for field in obj.fields}
+
+
+def _is_fake(obj):
+    return isinstance(obj, FakeNeutronObject)
+
+
+class BaseObjectTestCase(test_base.BaseTestCase):
+
+    def setUp(self):
+        super(BaseObjectTestCase, self).setUp()
+        self.context = context.get_admin_context()
+
+    @mock.patch.object(db_api, 'get_object', return_value=db_obj)
+    def test_get_by_id(self, get_object_mock):
+        obj = FakeNeutronObject.get_by_id(self.context, id='fake_id')
+        self.assertTrue(_is_fake(obj))
+        self.assertEqual(db_obj, get_obj_fields(obj))
+        get_object_mock.assert_called_once_with(
+            self.context, FakeNeutronObject.db_model, 'fake_id')
+
+    @mock.patch.object(db_api, 'get_objects', return_value=db_objs)
+    def test_get_objects(self, get_objects_mock):
+        objs = FakeNeutronObject.get_objects(self.context)
+        self.assertFalse(
+            filter(lambda obj: not _is_fake(obj), objs))
+        self.assertEqual(
+            sorted(db_objs),
+            sorted(get_obj_fields(obj) for obj in objs))
+        get_objects_mock.assert_called_once_with(
+            self.context, FakeNeutronObject.db_model)
+
+    def _check_equal(self, obj, db_obj):
+        self.assertEqual(
+            sorted(db_obj),
+            sorted(get_obj_fields(obj)))
+
+    @mock.patch.object(db_api, 'create_object', return_value=db_obj)
+    def test_create(self, create_mock):
+        obj = FakeNeutronObject(self.context, **db_obj)
+        self._check_equal(obj, db_obj)
+        obj.create()
+        self._check_equal(obj, db_obj)
+        create_mock.assert_called_once_with(
+            self.context, FakeNeutronObject.db_model, db_obj)
+
+    @mock.patch.object(db_api, 'create_object', return_value=db_obj)
+    def test_create_updates_from_db_object(self, *args):
+        obj = FakeNeutronObject(self.context, **db_objs[1])
+        self._check_equal(obj, db_objs[1])
+        obj.create()
+        self._check_equal(obj, db_obj)
+
+    @mock.patch.object(db_api, 'update_object', return_value=db_obj)
+    def test_update_no_changes(self, update_mock):
+        obj = FakeNeutronObject(self.context, **db_obj)
+        self._check_equal(obj, db_obj)
+        obj.update()
+        self.assertTrue(update_mock.called)
+
+        # consequent call to update does not try to update database
+        update_mock.reset_mock()
+        obj.update()
+        self._check_equal(obj, db_obj)
+        self.assertFalse(update_mock.called)
+
+    @mock.patch.object(db_api, 'update_object', return_value=db_obj)
+    def test_update_changes(self, update_mock):
+        obj = FakeNeutronObject(self.context, **db_obj)
+        self._check_equal(obj, db_obj)
+        obj.update()
+        self._check_equal(obj, db_obj)
+        update_mock.assert_called_once_with(
+            self.context, FakeNeutronObject.db_model, db_obj['id'], db_obj)
+
+    @mock.patch.object(db_api, 'update_object', return_value=db_obj)
+    def test_update_updates_from_db_object(self, *args):
+        obj = FakeNeutronObject(self.context, **db_objs[1])
+        self._check_equal(obj, db_objs[1])
+        obj.update()
+        self._check_equal(obj, db_obj)
+
+    @mock.patch.object(db_api, 'delete_object')
+    def test_delete(self, delete_mock):
+        obj = FakeNeutronObject(self.context, **db_obj)
+        self._check_equal(obj, db_obj)
+        obj.delete()
+        self._check_equal(obj, db_obj)
+        delete_mock.assert_called_once_with(
+            self.context, FakeNeutronObject.db_model, db_obj['id'])