Comment 0 for bug 1781880

Affected version: Pike+
Related commit: https://git.openstack.org/cgit/openstack/nova/commit/?id=0df91a7f799060cd2e9b8a0adac1efacb974bcb3

How to reproduce:
1. Set servicegroup_driver=mc in and enable_new_services=False in nova.conf
2. Add new compute host, start nova-compute service. Service becomes disabled, and field updated_at is NULL in nova.services table in DB.
3. Execute nova service-list:

Trace in the nova-api-os-compute logs:

ERROR nova.api.openstack.extensions [req-6034517c-bc29-4ebe-931e-8726fd934bee e05fb82b34cd4265a839f2482debb973 b5d263d6d7c24b84b335f4f00ae6d7c9] Unexpected exception in API method: TypeError: can't compare datetime.datetime to NoneType
TRACE nova.api.openstack.extensions Traceback (most recent call last):
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/api/openstack/extensions.py", line 336, in wrapped
TRACE nova.api.openstack.extensions return f(*args, **kwargs)
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/api/openstack/compute/services.py", line 261, in index
TRACE nova.api.openstack.extensions _services = self._get_services_list(req, ['forced_down'])
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/api/openstack/compute/services.py", line 115, in _get_services_list
TRACE nova.api.openstack.extensions for svc in _services]
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/api/openstack/compute/services.py", line 83, in _get_service_detail
TRACE nova.api.openstack.extensions updated_time = self.servicegroup_api.get_updated_time(svc)
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/servicegroup/api.py", line 84, in get_updated_time
TRACE nova.api.openstack.extensions return self._driver.updated_time(member)
TRACE nova.api.openstack.extensions File "/usr/lib/python2.7/dist-packages/nova/servicegroup/drivers/mc.py", line 81, in updated_time
TRACE nova.api.openstack.extensions if updated_time_in_db <= updated_time_in_mc:
TRACE nova.api.openstack.extensions TypeError: can't compare datetime.datetime to NoneType
TRACE nova.api.openstack.extensions
2018-07-16 11:40:16,437.437 2096 INFO nova.api.openstack.wsgi [req-6034517c-bc29-4ebe-931e-8726fd934bee e05fb82b34cd4265a839f2482debb973 b5d263d6d7c24b84b335f4f00ae6d7c9] HTTP exception thrown: Unexpected API Error. Please report this at http://bugs.launchpad.net/nova/ and attach the Nova API log if possible.
<type 'exceptions.TypeError'>