Adds regression test for bug LP#2085135

Related-Bug: #2085135
Change-Id: Id50413e2cff19bc3e510506ad2d7703c86155f59
Signed-off-by: Julien Le Jeune <julien.le-jeune@ovhcloud.com>
(cherry picked from commit 4073297ae3)
(cherry picked from commit fb2706a8ba)
(cherry picked from commit 2674b64ba7)

nova/tests/functional/regressions/test_bug_2085135.py

@@ -0,0 +1,75 @@
+# 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 nova import context
+from nova.db.main import api as db
+from nova import exception
+from nova import objects
+from nova.objects import host_mapping
+from nova import test
+from nova.tests import fixtures
+from nova import utils
+
+
+class HostMappingDiscoveryTestFail(test.TestCase):
+    """Regression test for bug 2085135
+    """
+
+    def setUp(self):
+        super().setUp()
+        self.ctxt = context.get_admin_context()
+
+        api_fixture = self.useFixture(fixtures.OSAPIFixture(
+            api_version='v2.1'))
+        self.admin_api = api_fixture.admin_api
+        self.admin_api.microversion = 'latest'
+
+    def test_discover_host_fail_after_service_deletion(self):
+        # Create compute
+        host_name = "compute-1"
+        service = self._start_compute(host_name)
+
+        # Store its node uuid
+        node_uuid = service.service_ref.compute_node.uuid
+
+        # Now delete its service
+        # It will delete the related compute node and host mapping
+        self.admin_api.api_delete(
+            '/os-services/%s' % service.service_ref.uuid)
+        # Check its deletion
+        self.assertRaises(exception.HostBinaryNotFound,
+            db.service_get_by_host_and_binary,
+            self.ctxt, host_name, 'nova-compute')
+
+        # Check that compute node and its mappings have correctly been deleted
+        with utils.temporary_mutation(self.ctxt, read_deleted='yes'):
+            node = db.compute_node_get_by_nodename(self.ctxt, host_name)
+            self.assertEqual(node['deleted'], node['id'])
+        self.assertRaises(exception.HostMappingNotFound,
+            objects.HostMapping.get_by_host,
+            self.ctxt, host_name)
+
+        # Now recreate the service and compute node by updating its resources
+        # like if the services restarts
+        service.manager.update_available_resource(self.ctxt)
+
+        # At this point, service and compute come back to life
+        # with the same compute uuid
+        node = db.compute_node_get_by_nodename(self.ctxt, host_name)
+        self.assertEqual(node['deleted'], 0)
+        self.assertEqual(node['uuid'], node_uuid)
+
+        # Bug #2085135: node should be unmapped and be discoverable
+        self.assertEqual(node['mapped'], 1)
+        mappings = host_mapping.discover_hosts(
+            self.ctxt, status_fn=lambda m: None)
+        self.assertEqual(0, len(mappings))