diff --git a/lib/xos-api/tests/test_orm.py b/lib/xos-api/tests/test_orm.py
new file mode 100644
index 0000000..86be969
--- /dev/null
+++ b/lib/xos-api/tests/test_orm.py
@@ -0,0 +1,1090 @@
+# Copyright 2017-present Open Networking Foundation
+#
+# 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.
+
+from __future__ import print_function
+
+import os
+import random
+import string
+import sys
+import unittest
+
+try:  # python 3
+    from io import StringIO
+    from unittest.mock import patch
+except ImportError:  # python 2
+    from StringIO import StringIO
+    from mock import patch
+
+
+# by default, use fake stub rather than real core
+USE_FAKE_STUB = True
+
+PARENT_DIR = os.path.join(os.path.dirname(__file__), "..")
+
+
+class TestORM(unittest.TestCase):
+    def setUp(self):
+        from xosconfig import Config
+
+        test_path = os.path.abspath(os.path.dirname(os.path.realpath(__file__)))
+        config = os.path.join(test_path, "test_config.yaml")
+        Config.clear()
+        Config.init(config, "synchronizer-config-schema.yaml")
+        if USE_FAKE_STUB:
+            sys.path.append(PARENT_DIR)
+
+        # Import these after config, in case they depend on config
+        from xosapi.orm import ORMQuerySet, ORMLocalObjectManager
+
+        self.ORMQuerySet = ORMQuerySet
+        self.ORMLocalObjectManager = ORMLocalObjectManager
+
+    def tearDown(self):
+        if USE_FAKE_STUB:
+            sys.path.remove(PARENT_DIR)
+
+    def make_coreapi(self):
+        if USE_FAKE_STUB:
+            import xosapi.orm
+            from fake_stub import FakeStub, FakeProtos, FakeObj
+
+            xosapi.orm.import_convenience_methods()
+
+            stub = FakeStub()
+            api = xosapi.orm.ORMStub(
+                stub=stub,
+                package_name="xos",
+                protos=FakeProtos(),
+                empty=FakeObj,
+                enable_backoff=False,
+            )
+            return api
+        else:
+            return xos_grpc_client.coreapi
+
+    def test_repr_name(self):
+        orm = self.make_coreapi()
+        s = orm.Slice(name="foo")
+        self.assertNotEqual(s, None)
+        self.assertEqual(repr(s), "<Slice: foo>")
+
+    def test_str_name(self):
+        orm = self.make_coreapi()
+        s = orm.Slice(name="foo")
+        self.assertNotEqual(s, None)
+        self.assertEqual(str(s), "foo")
+
+    def test_dumpstr_name(self):
+        orm = self.make_coreapi()
+        s = orm.Slice(name="foo")
+        self.assertNotEqual(s, None)
+        self.assertEqual(s.dumpstr(), 'name: "foo"\n')
+
+    def test_repr_noname(self):
+        orm = self.make_coreapi()
+        s = orm.Slice()
+        self.assertNotEqual(s, None)
+        self.assertEqual(repr(s), "<Slice: id-0>")
+
+    def test_str_noname(self):
+        orm = self.make_coreapi()
+        s = orm.Slice()
+        self.assertNotEqual(s, None)
+        self.assertEqual(str(s), "Slice-0")
+
+    def test_dumpstr_noname(self):
+        orm = self.make_coreapi()
+        s = orm.Slice()
+        self.assertNotEqual(s, None)
+        self.assertEqual(s.dumpstr(), "")
+
+    def test_dump(self):
+        """ dump() is like dumpstr() but prints to stdout. Mock stdout by using a stringIO. """
+
+        orm = self.make_coreapi()
+        s = orm.Slice(name="foo")
+        self.assertNotEqual(s, None)
+        with patch("sys.stdout", new_callable=StringIO) as mock_stdout:
+            s.dump()
+            self.assertEqual(mock_stdout.getvalue(), 'name: "foo"\n\n')
+
+    def test_create(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+
+    def test_get(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        got_site = orm.Site.objects.get(id=site.id)
+        self.assertNotEqual(got_site, None)
+        self.assertEqual(got_site.id, site.id)
+
+    def test_invalidate_cache(self):
+        orm = self.make_coreapi()
+        testModel = orm.TestModel()
+
+        # populate the caches with some placeholders we can test for
+        testModel.cache = {"a": 1}
+        testModel.reverse_cache = {"b": 2}
+
+        testModel.invalidate_cache()
+
+        self.assertEqual(testModel.cache, {})
+        self.assertEqual(testModel.reverse_cache, {})
+
+    def test_save_new(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+
+    def test_save_existing(self):
+        orm = self.make_coreapi()
+        orig_len_sites = len(orm.Site.objects.all())
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+
+        # there should be one new site
+        self.assertEqual(len(orm.Site.objects.all()), orig_len_sites + 1)
+
+        # retrieve the site, and update it
+        created_site_id = site.id
+        site = orm.Site.objects.get(id=created_site_id)
+        site.name = "mysitetwo"
+        site.save()
+
+        # the site_id should not have changed
+        self.assertEqual(site.id, created_site_id)
+
+        # there should still be only one new site
+        self.assertEqual(len(orm.Site.objects.all()), orig_len_sites + 1)
+
+        # the name should have changed
+        self.assertEqual(orm.Site.objects.get(id=created_site_id).name, "mysitetwo")
+
+    def test_delete(self):
+        orm = self.make_coreapi()
+        orig_len_sites = len(orm.Site.objects.all())
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        site.delete()
+        sites = orm.Site.objects.all()
+        self.assertEqual(len(sites), orig_len_sites)
+
+    def test_objects_all(self):
+        orm = self.make_coreapi()
+        orig_len_sites = len(orm.Site.objects.all())
+        site = orm.Site(name="mysite")
+        site.save()
+        sites = orm.Site.objects.all()
+        self.assertEqual(len(sites), orig_len_sites + 1)
+
+    def test_objects_first(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        site = orm.Site.objects.first()
+        self.assertNotEqual(site, None)
+
+    def test_content_type_map(self):
+        orm = self.make_coreapi()
+        self.assertTrue("Slice" in orm.content_type_map.values())
+        self.assertTrue("Site" in orm.content_type_map.values())
+        self.assertTrue("Tag" in orm.content_type_map.values())
+
+    def test_foreign_key_get(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site_id=site.id, creator_id=user.id)
+        slice.save()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+
+    def test_foreign_key_set_with_invalidate(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site=site, creator_id=user.id)
+        slice.save()
+        slice.invalidate_cache()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+    def test_foreign_key_set_without_invalidate(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site=site, creator_id=user.id)
+        slice.save()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id in slice.site.slices_ids)
+            ids_from_models = [x.id for x in slice.site.slices.all()]
+            self.assertTrue(slice.id in ids_from_models)
+
+    def test_foreign_key_reset(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site=site, creator_id=user.id)
+        slice.save()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id in site.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+        site2 = orm.Site(name="mysite2")
+        site2.save()
+        slice.name = "mysite2_foo"
+        slice.site = site2
+        slice.save()
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site2.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id not in site.slices_ids)
+            self.assertTrue(slice.id in site2.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+            ids_from_models1 = [x.id for x in site.slices.all()]
+            self.assertTrue(slice.id not in ids_from_models1)
+            ids_from_models2 = [x.id for x in site2.slices.all()]
+            self.assertTrue(slice.id in ids_from_models2)
+
+    def test_foreign_key_back_and_forth_even(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site=site, creator_id=user.id)
+        slice.save()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id in site.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+        site2 = orm.Site(name="mysite2")
+        site2.save()
+        slice.name = "mysite2_foo"
+        slice.site = site2
+        slice.site = site
+        slice.site = site2
+        slice.site = site
+        slice.save()
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id not in site2.slices_ids)
+            self.assertTrue(slice.id in site.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+    def test_foreign_key_back_and_forth_odd(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(name="mysite_foo", site=site, creator_id=user.id)
+        slice.save()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id in site.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+        site2 = orm.Site(name="mysite2")
+        site2.save()
+        slice.name = "mysite2_foo"
+        slice.site = site2
+        slice.site = site
+        slice.site = site2
+        slice.site = site
+        slice.site = site2
+        slice.save()
+        self.assertNotEqual(slice.site, None)
+        self.assertEqual(slice.site.id, site2.id)
+        if not USE_FAKE_STUB:
+            self.assertTrue(slice.id not in site.slices_ids)
+            self.assertTrue(slice.id in site2.slices_ids)
+            self.assertTrue(slice.id in slice.site.slices_ids)
+
+    def test_foreign_key_create_null(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        slice = orm.Slice(
+            name="mysite_foo", site=site, service=None, creator_id=user.id
+        )
+        slice.save()
+        slice.invalidate_cache()
+        self.assertTrue(slice.id > 0)
+        self.assertEqual(slice.service, None)
+
+    def test_foreign_key_set_null(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        user = orm.User(
+            email="fake_"
+            + "".join(
+                random.choice(string.ascii_uppercase + string.digits) for _ in range(10)
+            ),
+            site_id=site.id,
+        )
+        user.save()
+        self.assertTrue(user.id > 0)
+        service = orm.Service(name="myservice")
+        service.save()
+        self.assertTrue(service.id > 0)
+        # start out slice.service is non-None
+        slice = orm.Slice(
+            name="mysite_foo", site=site, service=service, creator_id=user.id
+        )
+        slice.save()
+        slice.invalidate_cache()
+        self.assertTrue(slice.id > 0)
+        self.assertNotEqual(slice.service, None)
+        self.assertEqual(slice.service.id, service.id)
+        # now set it to None
+        slice.service = None
+        slice.save()
+        slice.invalidate_cache()
+        self.assertEqual(slice.service, None)
+
+    def test_generic_foreign_key_get(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        tag = orm.Tag(
+            service=service,
+            name="mytag",
+            value="somevalue",
+            content_type=site.self_content_type_id,
+            object_id=site.id,
+        )
+        tag.save()
+        self.assertTrue(tag.id > 0)
+        self.assertNotEqual(tag.content_object, None)
+        self.assertEqual(tag.content_object.id, site.id)
+
+    def test_generic_foreign_key_get_decl(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        tag = orm.Tag(
+            service=service,
+            name="mytag",
+            value="somevalue",
+            content_type=site.self_content_type_id + "_decl",
+            object_id=site.id,
+        )
+        tag.save()
+        self.assertTrue(tag.id > 0)
+        self.assertNotEqual(tag.content_object, None)
+        self.assertEqual(tag.content_object.id, site.id)
+
+    def test_generic_foreign_key_get_bad_contenttype(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        tag = orm.Tag(
+            service=service,
+            name="mytag",
+            value="somevalue",
+            content_type="does_not_exist",
+            object_id=site.id,
+        )
+        tag.save()
+        self.assertTrue(tag.id > 0)
+        with self.assertRaises(Exception) as e:
+
+            self.assertEqual(
+                str(e.exception),
+                "Content_type does_not_exist not found in self.content_type_map",
+            )
+
+    def test_generic_foreign_key_get_bad_id(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        tag = orm.Tag(
+            service=service,
+            name="mytag",
+            value="somevalue",
+            content_type=site.self_content_type_id,
+            object_id=4567,
+        )
+        tag.save()
+        self.assertTrue(tag.id > 0)
+        with self.assertRaises(Exception) as e:
+            self.assertEqual(
+                str(e.exception), "Object 4567 of model Site was not found"
+            )
+
+    def test_generic_foreign_key_set(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        site = orm.Site(name="mysite")
+        site.save()
+        self.assertTrue(site.id > 0)
+        tag = orm.Tag(service=service, name="mytag", value="somevalue")
+        tag.content_object = site
+        tag.invalidate_cache()
+        self.assertEqual(tag.content_type, site.self_content_type_id)
+        self.assertEqual(tag.object_id, site.id)
+        tag.save()
+        self.assertTrue(tag.id > 0)
+        self.assertNotEqual(tag.content_object, None)
+        self.assertEqual(tag.content_object.id, site.id)
+
+    def test_leaf_model_trivial(self):
+        orm = self.make_coreapi()
+        service = orm.Service(name="myservice")
+        service.save()
+        self.assertEqual(service.leaf_model_name, "Service")
+
+    def test_leaf_model_descendant(self):
+        orm = self.make_coreapi()
+        onos_service = orm.ONOSService(name="myservice")
+        onos_service.save()
+        self.assertEqual(onos_service.model_name, "ONOSService")
+        self.assertEqual(onos_service.leaf_model_name, "ONOSService")
+
+        service = orm.Service.objects.get(id=onos_service.id)
+        self.assertEqual(service.id, onos_service.id)
+        self.assertEqual(service.model_name, "Service")
+        self.assertEqual(service.leaf_model_name, "ONOSService")
+
+        onos_service_cast = service.leaf_model
+        self.assertEqual(onos_service_cast.model_name, "ONOSService")
+        self.assertEqual(onos_service_cast.leaf_model_name, "ONOSService")
+        self.assertEqual(onos_service_cast.id, onos_service.id)
+
+    def test_field_null(self):
+        """ In a saved object, if a nullable field is left set to None, make sure the ORM returns None """
+
+        orm = self.make_coreapi()
+        tm = orm.TestModel()
+        tm.save()
+
+        tm = orm.TestModel.objects.all()[0]
+        self.assertFalse(tm._wrapped_class.HasField("intfield"))
+        self.assertEqual(tm.intfield, None)
+
+    def test_field_null_new(self):
+        """ For models that haven't been saved yet, reading the field should return the gRPC default """
+
+        orm = self.make_coreapi()
+        tm = orm.TestModel()
+
+        self.assertEqual(tm.intfield, 0)
+
+    def test_field_non_null(self):
+        """ In a saved object, if a nullable field is set to a value, then make sure the ORM returns the value """
+
+        orm = self.make_coreapi()
+        tm = orm.TestModel(intfield=3)
+        tm.save()
+
+        tm = orm.TestModel.objects.all()[0]
+        self.assertEqual(tm.intfield, 3)
+
+    def test_field_set_null(self):
+        """ Setting a field to None is not allowed """
+
+        orm = self.make_coreapi()
+        tm = orm.TestModel()
+        with self.assertRaises(Exception) as e:
+            tm.intfile = None
+        self.assertEqual(
+            str(e.exception),
+            "Setting a non-foreignkey field to None is not supported",
+        )
+
+    def test_query_iexact(self):
+        orm = self.make_coreapi()
+        with patch.object(orm.grpc_stub, "FilterTestModel", autospec=True) as filter:
+            orm.TestModel.objects.filter(name__iexact="foo")
+            self.assertEqual(filter.call_count, 1)
+            q = filter.call_args[0][0]
+
+            self.assertEqual(q.kind, q.DEFAULT)
+            self.assertEqual(len(q.elements), 1)
+            self.assertEqual(q.elements[0].operator, q.elements[0].IEXACT)
+            self.assertEqual(q.elements[0].sValue, "foo")
+
+    def test_query_equal(self):
+        orm = self.make_coreapi()
+        with patch.object(orm.grpc_stub, "FilterTestModel", autospec=True) as filter:
+            orm.TestModel.objects.filter(name="foo")
+            self.assertEqual(filter.call_count, 1)
+            q = filter.call_args[0][0]
+
+            self.assertEqual(q.kind, q.DEFAULT)
+            self.assertEqual(len(q.elements), 1)
+            self.assertEqual(q.elements[0].operator, q.elements[0].EQUAL)
+            self.assertEqual(q.elements[0].sValue, "foo")
+
+    def test_ORMWrapper_dict(self):
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel(intfield=7, stringfield="foo")
+
+        self.assertDictEqual(testModel._dict, {"intfield": 7, "stringfield": "foo"})
+
+    def test_ORMWrapper_new_diff(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite")
+
+        self.assertEqual(site.is_new, True)
+        self.assertEqual(site._dict, {"name": "mysite"})
+        self.assertEqual(site.diff, {})
+        self.assertEqual(site.changed_fields, ["name"])
+        self.assertEqual(site.has_field_changed("name"), False)
+        self.assertEqual(site.has_field_changed("login_base"), False)
+
+        site.login_base = "bar"
+
+        self.assertEqual(site._dict, {"login_base": "bar", "name": "mysite"})
+        self.assertEqual(site.diff, {"login_base": (None, "bar")})
+        self.assertIn("name", site.changed_fields)
+        self.assertIn("login_base", site.changed_fields)
+        self.assertEqual(site.has_field_changed("name"), False)
+        self.assertEqual(site.has_field_changed("login_base"), True)
+        self.assertEqual(site.get_field_diff("login_base"), (None, "bar"))
+
+    def test_ORMWrapper_existing_diff(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite", login_base="foo")
+        site.save()
+        site = orm.Site.objects.first()
+
+        self.assertEqual(site.is_new, False)
+        self.assertEqual(site._dict, {"id": 1, "name": "mysite", "login_base": "foo"})
+        self.assertEqual(site.diff, {})
+        self.assertEqual(site.changed_fields, [])
+        self.assertEqual(site.has_field_changed("name"), False)
+        self.assertEqual(site.has_field_changed("login_base"), False)
+
+        site.login_base = "bar"
+
+        self.assertEqual(site._dict, {"id": 1, "login_base": "bar", "name": "mysite"})
+        self.assertEqual(site.diff, {"login_base": ("foo", "bar")})
+        self.assertIn("login_base", site.changed_fields)
+        self.assertEqual(site.has_field_changed("name"), False)
+        self.assertEqual(site.has_field_changed("login_base"), True)
+
+    def test_ORMWrapper_diff_after_save(self):
+        orm = self.make_coreapi()
+        site = orm.Site(name="mysite", login_base="foo")
+        site.save()
+        site = orm.Site.objects.first()
+
+        self.assertEqual(site.diff, {})
+
+        site.login_base = "bar"
+
+        self.assertEqual(site.diff, {"login_base": ("foo", "bar")})
+
+        site.save()
+
+        self.assertEqual(site.diff, {})
+
+    def test_ORMWrapper_recompute_initial(self):
+        """ For saved models, Recompute_initial should take recompute the set of initial values, removing all items
+            from the diff set.
+        """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModel.intfield = 9
+        self.assertEqual(testModel.changed_fields, ["intfield"])
+
+        testModel.recompute_initial()
+        self.assertEqual(testModel.changed_fields, [])
+
+    def test_ORMWrapper_create_attr(self):
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.create_attr("some_new_attribute", "foo")
+        self.assertEqual(testModel.some_new_attribute, "foo")
+
+    def test_ORMWrapper_save_changed_fields(self):
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel(intfield=7, stringfield="foo")
+        testModel.save()
+
+        testModel.intfield = 9
+
+        with patch.object(
+            orm.grpc_stub, "UpdateTestModel", wraps=orm.grpc_stub.UpdateTestModel
+        ) as update:
+            testModel.save_changed_fields()
+
+            self.assertEqual(update.call_count, 1)
+            self.assertIn("metadata", update.call_args[1])
+            update_fields_arg = [
+                x[1] for x in update.call_args[1]["metadata"] if x[0] == "update_fields"
+            ]
+            self.assertEqual(update_fields_arg, ["intfield"])
+
+    def test_ORMWrapper_get_generic_foreignkeys(self):
+        """ Currently this is a placeholder that returns an empty list """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        self.assertEqual(testModel.get_generic_foreignkeys(), [])
+
+    def test_ORMWrapper_gen_fkmap(self):
+        """ TestModelTwo includes a foreignkey relation to TestModel, and the fkmap should contain that relation """
+
+        orm = self.make_coreapi()
+
+        testModelTwo = orm.TestModelTwo()
+
+        self.assertDictEqual(
+            testModelTwo.gen_fkmap(),
+            {
+                "testmodel": {
+                    "kind": "fk",
+                    "modelName": "TestModel",
+                    "reverse_fieldName": "testmodeltwos",
+                    "src_fieldName": "testmodel_id",
+                }
+            },
+        )
+
+    def test_ORMWrapper_gen_reverse_fkmap(self):
+        """ TestModel includes a reverse relation back to TestModelTwo, and the reverse_fkmap should contain that
+            relation.
+        """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+
+        self.assertDictEqual(
+            testModel.gen_reverse_fkmap(),
+            {
+                "testmodeltwos": {
+                    "modelName": "TestModelTwo",
+                    "src_fieldName": "testmodeltwos_ids",
+                    "writeable": False,
+                }
+            },
+        )
+
+    def test_ORMWrapper_fk_resolve(self):
+        """ If we create a TestModelTwo that has a foreign key reference to a TestModel, then calling fk_resolve should
+            return that model.
+        """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModelTwo = orm.TestModelTwo(testmodel_id=testModel.id)
+
+        testModel_resolved = testModelTwo.fk_resolve("testmodel")
+        self.assertEqual(testModel_resolved.id, testModel.id)
+
+        # the cache should have been populated
+        self.assertIn(("testmodel", testModel_resolved), testModelTwo.cache.items())
+
+    def test_ORMWrapper_reverse_fk_resolve(self):
+        """ If a TestModelTwo has a relation to TestModel, then TestModel's reverse_fk should be resolvable to a list
+            of TestModelTwo objects.
+        """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModelTwo = orm.TestModelTwo(testmodel_id=testModel.id)
+        testModelTwo.save()
+
+        # fake_stub.py doesn't populate the reverse relations for us, so force what the server would have done...
+        testModel._wrapped_class.testmodeltwos_ids = [testModelTwo.id]
+
+        testModelTwos_resolved = testModel.reverse_fk_resolve("testmodeltwos")
+        self.assertEqual(testModelTwos_resolved.count(), 1)
+
+        # the reverse_cache should have been populated
+        self.assertIn(
+            ("testmodeltwos", testModelTwos_resolved), testModel.reverse_cache.items()
+        )
+
+    def test_ORMWrapper_fk_set(self):
+        """ fk_set will set the testmodel field on TesTModelTwo to point to the TestModel. """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModelTwo = orm.TestModelTwo()
+
+        testModelTwo.fk_set("testmodel", testModel)
+
+        self.assertEqual(testModelTwo.testmodel_id, testModel.id)
+
+    def test_ORMWrapper_post_save_fixups_remove(self):
+        """ Apply a post_save_fixup that removes a reverse foreign key """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModelTwo = orm.TestModelTwo(testmodel_id=testModel.id)
+
+        # fake_stub.py doesn't populate the reverse relations for us, so force what the server would have done...
+        testModel._wrapped_class.testmodeltwos_ids = [testModelTwo.id]
+
+        post_save_fixups = [
+            {
+                "src_fieldName": "testmodel",
+                "dest_id": None,  # this field appears to not be used...
+                "dest_model": testModel,
+                "remove": True,
+                "reverse_fieldName": "testmodeltwos",
+            }
+        ]
+
+        testModelTwo.post_save_fixups = post_save_fixups
+        testModelTwo.do_post_save_fixups()
+
+        self.assertEqual(testModel._wrapped_class.testmodeltwos_ids, [])
+
+    def test_ORMWrapper_post_save_fixups_add(self):
+        """ Apply a post_save_fixup that adds a reverse foreign key """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel()
+        testModel.save()
+
+        testModelTwo = orm.TestModelTwo(testmodel_id=testModel.id)
+        testModelTwo.save()
+
+        # Make sure the reverse_relation is unpopulated. This should be the case, as fake_stub.py() doesn't populate
+        # the reverse relation. But let's be sure, in case someone fixes that.
+        testModel._wrapped_class.testmodeltwos_ids = []
+
+        post_save_fixups = [
+            {
+                "src_fieldName": "testmodel",
+                "dest_id": None,  # this field appears to not be used...
+                "dest_model": testModel,
+                "remove": False,
+                "reverse_fieldName": "testmodeltwos",
+            }
+        ]
+
+        testModelTwo.post_save_fixups = post_save_fixups
+        testModelTwo.do_post_save_fixups()
+
+        self.assertEqual(testModel._wrapped_class.testmodeltwos_ids, [testModelTwo.id])
+
+    def test_ORMWrapper_tologdict(self):
+        """ Tologdict contains the model name and id, used for structured logging """
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel(intfield=7, stringfile="foo")
+
+        self.assertDictEqual(
+            testModel.tologdict(), {"model_name": "TestModel", "pk": 0}
+        )
+
+    def test_ORMWrapper_ansible_tag(self):
+        """ Ansible_tag is used by old-style synchronizers. Deprecated. """
+
+        orm = self.make_coreapi()
+
+        testModel = orm.TestModel(id=7)
+
+        self.assertEqual(testModel.ansible_tag, "TestModel_7")
+
+    def test_deleted_objects_all(self):
+        orm = self.make_coreapi()
+        orig_len_sites = len(orm.Site.objects.all())
+        orig_len_deleted_sites = len(orm.Site.deleted_objects.all())
+        site = orm.Site(name="mysite")
+        site.save()
+        site.delete()
+        sites = orm.Site.objects.all()
+        self.assertEqual(len(sites), orig_len_sites)
+        deleted_sites = orm.Site.deleted_objects.all()
+        self.assertEqual(len(deleted_sites), orig_len_deleted_sites + 1)
+
+    def test_deleted_objects_filter(self):
+        orm = self.make_coreapi()
+        with patch.object(
+            orm.grpc_stub, "FilterTestModel", wraps=orm.grpc_stub.FilterTestModel
+        ) as filter:
+            foo = orm.TestModel(name="foo")
+            foo.save()
+            foo.delete()
+
+            # There should be no live objects
+            objs = orm.TestModel.objects.filter(name="foo")
+            self.assertEqual(len(objs), 0)
+
+            # There should be one deleted object
+            deleted_objs = orm.TestModel.deleted_objects.filter(name="foo")
+            self.assertEqual(len(deleted_objs), 1)
+
+            # Two calls, one for when we checked live objects, the other for when we checked deleted objects
+            self.assertEqual(filter.call_count, 2)
+            q = filter.call_args[0][0]
+
+            # Now spy on the query that was generated, to make sure it looks like we expect
+            self.assertEqual(q.kind, q.SYNCHRONIZER_DELETED_OBJECTS)
+            self.assertEqual(len(q.elements), 1)
+            self.assertEqual(q.elements[0].operator, q.elements[0].EQUAL)
+            self.assertEqual(q.elements[0].sValue, "foo")
+
+    def test_ORMQuerySet_first_nonempty(self):
+        qs = self.ORMQuerySet([1, 2, 3])
+        self.assertEqual(qs.first(), 1)
+
+    def test_ORMQuerySet_first_empty(self):
+        qs = self.ORMQuerySet([])
+        self.assertEqual(qs.first(), None)
+
+    def test_ORMQuerySet_exists_nonempty(self):
+        qs = self.ORMQuerySet([1, 2, 3])
+        self.assertEqual(qs.exists(), True)
+
+    def test_ORMQuerySet_exists_empty(self):
+        qs = self.ORMQuerySet()
+        self.assertEqual(qs.exists(), False)
+
+    def test_ORMLocalObjectManager_nonempty(self):
+        """ Test all(), first(), exists(), and count() together since they're all closely related. Use a nonempty
+            list.
+        """
+        orm = self.make_coreapi()
+
+        t = orm.TestModel()
+        t.save()
+
+        lobjs = self.ORMLocalObjectManager(t.stub, "TestModel", [t.id], False)
+        self.assertEqual(len(lobjs.all()), 1)
+        self.assertEqual(lobjs.all()[0].id, t.id)
+        self.assertEqual(lobjs.exists(), True)
+        self.assertEqual(lobjs.count(), 1)
+        self.assertEqual(lobjs.first().id, t.id)
+
+    def test_ORMLocalObjectManager_empty(self):
+        """ Test all(), first(), exists(), and count() together since they're all closely related. Use an empty
+            list.
+        """
+        orm = self.make_coreapi()
+
+        t = orm.TestModel()
+        t.save()
+
+        lobjs = self.ORMLocalObjectManager(t.stub, "TestModel", [], False)
+        self.assertEqual(len(lobjs.all()), 0)
+        self.assertEqual(lobjs.exists(), False)
+        self.assertEqual(lobjs.count(), 0)
+        self.assertEqual(lobjs.first(), None)
+
+    def test_ORMLocalObjectManager_not_writeable(self):
+        """ An ORMLocalObjectManager that is not writeable should throw exceptions on add() and remove() """
+        orm = self.make_coreapi()
+
+        t = orm.TestModel()
+        t.save()
+
+        lobjs = self.ORMLocalObjectManager(t.stub, "TestModel", [t.id], False)
+
+        with self.assertRaises(Exception) as e:
+            lobjs.add(123)
+        self.assertEqual(str(e.exception), "Only ManyToMany lists are writeable")
+
+        with self.assertRaises(Exception) as e:
+            lobjs.remove(123)
+        self.assertEqual(str(e.exception), "Only ManyToMany lists are writeable")
+
+    def test_ORMLocalObjectManager_add(self):
+        orm = self.make_coreapi()
+
+        t = orm.TestModel()
+        t.save()
+
+        lobjs = self.ORMLocalObjectManager(t.stub, "TestModel", [], True)
+        lobjs.add(t)
+        self.assertEqual(lobjs.count(), 1)
+        self.assertEqual(lobjs.first().id, t.id)
+
+    def test_ORMLocalObjectManager_remove(self):
+        orm = self.make_coreapi()
+
+        t = orm.TestModel()
+        t.save()
+
+        lobjs = self.ORMLocalObjectManager(t.stub, "TestModel", [t.id], True)
+        lobjs.remove(t)
+        self.assertEqual(lobjs.count(), 0)
+
+
+def main():
+    global USE_FAKE_STUB
+    global xos_grpc_client
+
+    # Command-line argument of -R will cause this test to use a real grpc server
+    # rather than the fake stub.
+
+    if "-R" in sys.argv:
+        USE_FAKE_STUB = False
+        sys.argv.remove("-R")
+        # Note: will leave lots of litter (users, sites, etc) behind in the database
+
+    if USE_FAKE_STUB:
+        unittest.main()
+    else:
+        # This assumes xos-client python library is installed, and a gRPC server
+        # is available.
+
+        from xosapi import xos_grpc_client
+
+        print("Using xos-client library and core server")
+
+        def test_callback():
+            try:
+                sys.argv = sys.argv[
+                    :1
+                ]
+                # unittest does not like xos_grpc_client's command line
+                # arguments (TODO: find a cooperative approach)
+                unittest.main()
+            except SystemExit as e:
+                global exitStatus
+                exitStatus = e.code
+
+        xos_grpc_client.start_api_parseargs(test_callback)
+
+        sys.exit(exitStatus)
+
+
+if __name__ == "__main__":
+    main()