openstack
/
nova
Code Issues Proposed changes

Avoid error 500 on shelve task_state race 

When shelving a server and saving its new SHELVING task state, we
expect the current task state to be None and do not handle any
UnexpectedTaskStateError exceptions that the database layer may throw
at us. In those cases, we return an error 500 to the user, when in
actuality an error 409 conflict would be more appropriate. This
patch makes the API layer handle UnexpectedTaskStateError exceptions
and return a 409 to the user.

NOTE(artom) Conflicts:
 * nova/api/openstack/compute/shelve.py because
   InstanceUnknownCell stopped being handled as of
   95dc5d0ab5 in train
 * nova/tests/unit/api/openstack/compute/test_shelve.py due to the
   vm_states import that was present in train as of
   27b6c18c66 but is missing from stein.

Closes-bug: 1850694
Change-Id: Ie0b421cd5d3a5781c1dd09fab4ed013ece0f939d
(cherry picked from commit a423d8b277)
(cherry picked from commit 32dbd2f585)
This commit is contained in:
Artom Lifshitz 2019-10-30 14:03:49 -04:00
parent cd534177e5
commit 8ee59604dc
2 changed files with 21 additions and 1 deletions
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3
nova/api/openstack/compute/shelve.py
View File

@ -47,7 +47,8 @@ class ShelveController(wsgi.Controller):
self.compute_api.shelve(context, instance)
except exception.InstanceUnknownCell as e:
raise exc.HTTPNotFound(explanation=e.format_message())
except exception.InstanceIsLocked as e:
except (exception.InstanceIsLocked,
exception.UnexpectedTaskStateError) as e:
raise exc.HTTPConflict(explanation=e.format_message())
except exception.InstanceInvalidState as state_error:
common.raise_http_conflict_for_instance_invalid_state(state_error,

19
nova/tests/unit/api/openstack/compute/test_shelve.py
View File

@ -15,9 +15,12 @@
import mock
from oslo_policy import policy as oslo_policy
from oslo_utils.fixture import uuidsentinel
import six
import webob
from nova.api.openstack.compute import shelve as shelve_v21
from nova.compute import task_states
from nova.compute import vm_states
from nova import exception
from nova import policy
from nova import test
@ -42,6 +45,22 @@ class ShelvePolicyTestV21(test.NoDBTestCase):
self.assertRaises(webob.exc.HTTPConflict, self.controller._shelve,
self.req, uuidsentinel.fake, {})
@mock.patch('nova.api.openstack.common.get_instance')
@mock.patch('nova.objects.instance.Instance.save')
def test_shelve_task_state_race(self, mock_save, get_instance_mock):
instance = fake_instance.fake_instance_obj(
self.req.environ['nova.context'],
vm_state=vm_states.ACTIVE, task_state=None)
instance.launched_at = instance.created_at
get_instance_mock.return_value = instance
mock_save.side_effect = exception.UnexpectedTaskStateError(
instance_uuid=instance.uuid, expected=None,
actual=task_states.SHELVING)
ex = self.assertRaises(webob.exc.HTTPConflict, self.controller._shelve,
self.req, uuidsentinel.fake, body={'shelve': {}})
self.assertIn('Conflict updating instance', six.text_type(ex))
mock_save.assert_called_once_with(expected_task_state=[None])
@mock.patch('nova.api.openstack.common.get_instance')
def test_unshelve_locked_server(self, get_instance_mock):
get_instance_mock.return_value = (