random failure in octavia.tests.unit.cmd.test_prometheus_proxy.TestPrometheusProxyCMD.test_main

[Gregory Thiemonge]

reported by the RDO project on stable/yoga (a59d75ce):

https://trunk.rdoproject.org/centos9-yoga/component/octavia/a5/9d/a59d75cea7fae6f8750741544a1b94b5187ed653_70922990/rpmbuild.log

octavia.tests.unit.cmd.test_prometheus_proxy.TestPrometheusProxyCMD.test_main fails randomly

DEBUG: ==============================
DEBUG: Failed 1 tests - output below:
DEBUG: ==============================
DEBUG: octavia.tests.unit.cmd.test_prometheus_proxy.TestPrometheusProxyCMD.test_main
DEBUG: -----------------------------------------------------------------------------
DEBUG: Captured traceback:
DEBUG: ~~~~~~~~~~~~~~~~~~~
DEBUG: Traceback (most recent call last):
DEBUG: File "/usr/lib64/python3.9/unittest/mock.py", line 1336, in patched
DEBUG: return func(*newargs, **newkeywargs)
DEBUG: File "/builddir/build/BUILD/octavia-10.1.1.dev6/octavia/tests/unit/cmd/test_prometheus_proxy.py", line 169, in test_main
DEBUG: mock_serve_forever.assert_called_once()
DEBUG: File "/usr/lib64/python3.9/unittest/mock.py", line 886, in assert_called_once
DEBUG: raise AssertionError(msg)
DEBUG: AssertionError: Expected 'serve_forever' to have been called once. Called 0 times.

[Michael Johnson (johnsom)]

This code is gone in newer versions because python 3.8 had the newer approach available.
I'm guessing that something is using the port in this test environment, causing the test failure.

[Alfredo Moralejo (amoralej)]

Note that the test is also failing in Zed release with CentOS 9 and python 3.9 https://trunk.rdoproject.org/centos9-zed/component/octavia/00/0b/000b577f3e9c9ff7cb893e9f6e635753017a78c6_2966ced4/rpmbuild.log