Comment 8 for bug 1515326

Seen here in an openstackclient job:

http://logs.openstack.org/04/240804/3/gate/gate-osc-dsvm-functional/9a34c38/logs/screen-n-api.txt.gz?level=TRACE#_2015-11-11_22_52_34_533

2015-11-11 22:52:34.533 ERROR nova.api.openstack.extensions [req-4895a748-50ec-4d45-bfaa-28c170f6dee3 admin admin] Unexpected exception in API method
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions Traceback (most recent call last):
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/api/openstack/extensions.py", line 478, in wrapped
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return f(*args, **kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/api/validation/__init__.py", line 73, in wrapper
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return func(*args, **kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/api/validation/__init__.py", line 73, in wrapper
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return func(*args, **kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/api/openstack/compute/flavor_manage.py", line 80, in _create
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions is_public=is_public)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/compute/flavors.py", line 175, in create
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions flavor.create()
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/base.py", line 213, in wrapper
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return fn(self, *args, **kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/objects/flavor.py", line 177, in create
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions db_flavor = db.flavor_create(self._context, updates, projects=projects)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/db/api.py", line 1434, in flavor_create
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return IMPL.flavor_create(context, values, projects=projects)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/db/sqlalchemy/api.py", line 4638, in flavor_create
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions session = get_session()
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/opt/stack/new/nova/nova/db/sqlalchemy/api.py", line 172, in get_session
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions use_slave=use_slave, **kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 977, in get_session
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions return self._factory._writer_maker(**kwargs)
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions AttributeError: '_TransactionFactory' object has no attribute '_writer_maker'
2015-11-11 22:52:34.533 22634 ERROR nova.api.openstack.extensions