Reproduce bug #2025480 in a functional test

Written by gibi, I just cleaned it up.

Change-Id: I8386a846b3685b8d03c59334ccfb2efbd4afe427
Co-Authored-By: Balazs Gibizer <gibizer@gmail.com>
Related-Bug: #2025480
(cherry picked from commit 62300d4885549368f874b3e07b756017ff96c659)
(cherry picked from commit 477ff2667d7ecd218fa5163d86d2719979dcdcd3)
(cherry picked from commit 23c190a35839b396418d3e98af1e67587f9e9296)
(cherry picked from commit 7422642dd6e222959470b73dc6ba2450a792b9c7)

nova/tests/functional/regressions/test_bug_2025480.py

@@ -0,0 +1,87 @@
+# 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 unittest import mock
+
+from nova import context
+from nova.objects import compute_node
+from nova import test
+from nova.tests import fixtures as nova_fixtures
+from nova.tests.functional import fixtures as func_fixtures
+from nova.tests.functional import integrated_helpers
+
+
+class UnshelveUpdateAvailableResourcesPeriodicRace(
+        test.TestCase, integrated_helpers.InstanceHelperMixin):
+    def setUp(self):
+        super(UnshelveUpdateAvailableResourcesPeriodicRace, self).setUp()
+
+        placement = func_fixtures.PlacementFixture()
+        self.useFixture(placement)
+        self.placement = placement.api
+        self.neutron = nova_fixtures.NeutronFixture(self)
+        self.useFixture(self.neutron)
+        self.useFixture(nova_fixtures.GlanceFixture(self))
+        # Start nova services.
+        self.api = self.useFixture(nova_fixtures.OSAPIFixture(
+            api_version='v2.1')).admin_api
+        self.api.microversion = 'latest'
+        self.notifier = self.useFixture(
+            nova_fixtures.NotificationFixture(self))
+
+        self.start_service('conductor')
+        self.start_service('scheduler')
+
+    def test_unshelve_spawning_update_available_resources(self):
+        compute = self._start_compute('compute1')
+
+        server = self._create_server(
+            networks=[{'port': self.neutron.port_1['id']}])
+
+        node = compute_node.ComputeNode.get_by_nodename(
+            context.get_admin_context(), 'compute1')
+        self.assertEqual(1, node.vcpus_used)
+
+        # with default config shelve means immediate offload as well
+        req = {
+            'shelve': {}
+        }
+        self.api.post_server_action(server['id'], req)
+        self._wait_for_server_parameter(
+            server, {'status': 'SHELVED_OFFLOADED',
+                     'OS-EXT-SRV-ATTR:host': None})
+
+        node = compute_node.ComputeNode.get_by_nodename(
+            context.get_admin_context(), 'compute1')
+        self.assertEqual(0, node.vcpus_used)
+
+        def fake_spawn(*args, **kwargs):
+            self._run_periodics()
+
+        with mock.patch.object(
+                compute.driver, 'spawn', side_effect=fake_spawn):
+            req = {'unshelve': None}
+            self.api.post_server_action(server['id'], req)
+            self.notifier.wait_for_versioned_notifications(
+                'instance.unshelve.start')
+            self._wait_for_server_parameter(
+                server,
+                {
+                    'status': 'ACTIVE',
+                    'OS-EXT-STS:task_state': None,
+                    'OS-EXT-SRV-ATTR:host': 'compute1',
+                })
+
+        node = compute_node.ComputeNode.get_by_nodename(
+            context.get_admin_context(), 'compute1')
+        # This is the bug, the instance should have resources claimed
+        # self.assertEqual(1, node.vcpus_used)
+        self.assertEqual(0, node.vcpus_used)