On my CentOS system, this test can locally fail 30-50% of the time - tested from queens to master:
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Failed 1 tests - output below:
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neutron.tests.unit.scheduler.test_dhcp_agent_scheduler.TestNetworksFailover.test_filter_bindings
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Captured traceback:
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Traceback (most recent call last):
File "neutron/tests/base.py", line 177, in func
return f(self, *args, **kwargs)
File "neutron/tests/unit/scheduler/test_dhcp_agent_scheduler.py", line 527, in test_filter_bindings
self.assertIn(network_ids[2], res_ids)
File "/home/stack/neutron/.tox/py27/lib/python2.7/site-packages/testtools/testcase.py", line 417, in assertIn
self.assertThat(haystack, Contains(needle), message)
File "/home/stack/neutron/.tox/py27/lib/python2.7/site-packages/testtools/testcase.py", line 498, in assertThat
raise mismatch_error
testtools.matchers._impl.MismatchError: '8a6b1ce0-fc2e-40b0-bc98-a59722d96a3f' not in ['6f6c1774-b351-4763-a8d8-184c3bdf01de', '8cee4a38-63e8-4c71-99e9-611b61aa4c90']
The test creates 4 networks (random UUIDs), then 4 NetworkDhcpAgentBindings,
It then gets a list of these bindings with NetworkDhcpAgentBinding.get_objects() which uses a sort based on network_id by default.
This list is then used with _filter_bindings:
with mock.patch.object(self, 'agent_starting_up',
side_effect=[True, False]):
res = [b for b in self._filter_bindings(None, bindings_objs)]
[...]
res_ids = [b.network_id for b in res]
self.assertIn(network_ids[2], res_ids)
self.assertIn(network_ids[3], res_ids)
But as network_ids is not sorted, this can fail depending on the generated UUIDs. One example on my system:
network_ids:
['6f6c1774-b351-4763-a8d8-184c3bdf01de', '8cee4a38-63e8-4c71-99e9-611b61aa4c90', '8a6b1ce0-fc2e-40b0-bc98-a59722d96a3f', '4f476b11-085f-47bf-a27f-e300eb9a85b4']
binding_objs:
NetworkDhcpAgentBinding(dhcp_agent_id=1d6b3b74-afa1-410b-880e-be4f87ce7c6d,network_id=4f476b11-085f-47bf-a27f-e300eb9a85b4)
NetworkDhcpAgentBinding(dhcp_agent_id=07030f55-35cd-4386-853f-70777cdcae2b,network_id=6f6c1774-b351-4763-a8d8-184c3bdf01de)
NetworkDhcpAgentBinding(dhcp_agent_id=1d6b3b74-afa1-410b-880e-be4f87ce7c6d,network_id=8a6b1ce0-fc2e-40b0-bc98-a59722d96a3f)
NetworkDhcpAgentBinding(dhcp_agent_id=07030f55-35cd-4386-853f-70777cdcae2b,network_id=8cee4a38-63e8-4c71-99e9-611b61aa4c90)
which will give a (failing the test) res_ids: ['6f6c1774-b351-4763-a8d8-184c3bdf01de', '8cee4a38-63e8-4c71-99e9-611b61aa4c90']
I am not sure why upstream gates never seem to have the problem (as far as I have checked), but sorting the network_ids makes the test passing all the time
Fix proposed to branch: master
Review: https:/