That's not necessary. Moreover, if the socket units are stopped in
`setUpModule()`, then there exists a short timespan that we cannot call
`udevadm control`, as the control socket may not be opened yet.
If we run whole tests, then the first test is
NetworkctlTests.test_altname, and it calls `udevadm control` in `setUp()`.
Hence, the test may fail.
Fixes https://github.com/systemd/systemd-centos-ci/pull/512#issuecomment-1191591008.
Several DHCP client tests change the system timezone.
Let's save the current timezone at the beginning, and restore it with
the saved value at the end.
- introduce several helper functions
- do not list unit files, but remove the runtime unit directory in
tearDown().
- do not list used interfaces, but remove all interfaces previously not
exists in tearDown().
- save routes and routing policy rules before running tests, and flush
unnecessary routes and rules in each tearDown() calls.
- drop many time.sleep() calls.
- call tearDown() after each sub tests.
- shorten code.
- several coding style fixes.
- etc, etc...
Hopefully, this improves performance of the test.
`global` is needed only when assigning a new value to the global
variable; it's not necessary when modifying a mutable object (in our
case we just append items to the global list).
Otherwise, this easily trigger another exception:
```
======================================================================
ERROR: test_erspan_tunnel_v0 (__main__.NetworkdNetDevTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "./test/test-network/systemd-networkd-tests.py", line 686, in wait_online
check_output(*args, env=env)
File "./test/test-network/systemd-networkd-tests.py", line 65, in check_output
return subprocess.check_output(command, universal_newlines=True, **kwargs).rstrip()
File "/usr/lib64/python3.6/subprocess.py", line 356, in check_output
**kwargs).stdout
File "/usr/lib64/python3.6/subprocess.py", line 438, in run
output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['/usr/lib/systemd/systemd-networkd-wait-online', '--timeout=20s', '--interface=erspan99:routable', '--interface=erspan98:routable', '--interface=dummy98:degraded']' returned non-zero exit status 1.
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "./test/test-network/systemd-networkd-tests.py", line 1808, in test_erspan_tunnel_v0
self.wait_online(['erspan99:routable', 'erspan98:routable', 'dummy98:degraded'])
File "./test/test-network/systemd-networkd-tests.py", line 689, in wait_online
output = check_output(*networkctl_cmd, '-n', '0', 'status', link.split(':')[0], env=env)
File "./test/test-network/systemd-networkd-tests.py", line 65, in check_output
return subprocess.check_output(command, universal_newlines=True, **kwargs).rstrip()
File "/usr/lib64/python3.6/subprocess.py", line 356, in check_output
**kwargs).stdout
File "/usr/lib64/python3.6/subprocess.py", line 438, in run
output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['/usr/bin/networkctl', '-n', '0', 'status', 'erspan99']' returned non-zero exit status 1.
```
Luca Boccassi
Yu Watanabe
Frantisek Sumsal