add regression test case for bug 1978983

This change add a repoducer test for evacuating
a vm in the powering-off state

Related-Bug: #1978983
Change-Id: I5540df6c7497956219c06cff6f15b51c2c8bc299
(cherry picked from commit 5904c7f)

Author: auniyal61

nova/tests/functional/integrated_helpers.py

@@ -606,9 +606,11 @@ def _start_server(self, server):
         self.api.post_server_action(server['id'], {'os-start': None})
         return self._wait_for_state_change(server, 'ACTIVE')
 
-    def _stop_server(self, server):
+    def _stop_server(self, server, wait_for_stop=True):
         self.api.post_server_action(server['id'], {'os-stop': None})
-        return self._wait_for_state_change(server, 'SHUTOFF')
+        if wait_for_stop:
+            return self._wait_for_state_change(server, 'SHUTOFF')
+        return server
 
 
 class PlacementHelperMixin:

nova/tests/functional/regressions/test_bug_1978983.py

@@ -0,0 +1,78 @@
+# Copyright 2022 Red Hat, Inc.
+# All Rights Reserved.
+#
+# 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 test
+from nova.tests import fixtures as nova_fixtures
+from nova.tests.functional.api import client
+from nova.tests.functional import fixtures as func_fixtures
+from nova.tests.functional import integrated_helpers
+
+
+class EvacuateServerWithTaskState(
+    test.TestCase, integrated_helpers.InstanceHelperMixin,
+):
+    """Regression test for bug 1978983
+    If instance task state is powering-off or not None
+    instance should be allowed to evacuate.
+    """
+
+    def setUp(self):
+        super().setUp()
+        # Stub out external dependencies.
+        self.useFixture(nova_fixtures.NeutronFixture(self))
+        self.useFixture(nova_fixtures.GlanceFixture(self))
+        self.useFixture(func_fixtures.PlacementFixture())
+        self.useFixture(nova_fixtures.HostNameWeigherFixture())
+
+        # Start nova controller services.
+        self.start_service('conductor')
+        self.start_service('scheduler')
+
+        api_fixture = self.useFixture(nova_fixtures.OSAPIFixture(
+            api_version='v2.1'))
+        self.api = api_fixture.admin_api
+
+        self.src = self._start_compute(host='host1')
+        self.dest = self._start_compute(host='host2')
+
+    def test_evacuate_instance(self):
+        """Evacuating a server
+        """
+        server = self._create_server(networks=[])
+
+        self.api.microversion = 'latest'
+        server = self._wait_for_state_change(server, 'ACTIVE')
+        self.assertEqual('host1', server['OS-EXT-SRV-ATTR:host'])
+
+        # stop host1 compute service
+        self.src.stop()
+
+        # poweroff instance
+        self._stop_server(server, wait_for_stop=False)
+        server = self._wait_for_server_parameter(
+            server, {'OS-EXT-STS:task_state': 'powering-off'})
+
+        # FIXME(auniyal): As compute service is down in source node
+        # instance is stuck at powering-off, evacuation fails with
+        # msg: Cannot 'evacuate' instance <instance-id> while it is in
+        # task_state powering-off (HTTP 409)
+
+        ex = self.assertRaises(
+            client.OpenStackApiException,
+            self._evacuate_server,
+            server,
+            expected_host=self.dest.host)
+        self.assertEqual(409, ex.response.status_code)