Traceback when checking linkspeed for some interface types

[Frode Nordahl]

2022-09-22 06:33:29 ERROR unit.magpie/0.juju-log server.go:316 magpie:0: Hook error:
Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-magpie-0/.venv/lib/python3.8/site-packages/charms/reactive/__init__.py", line 74, in main
    bus.dispatch(restricted=restricted_mode)
  File "/var/lib/juju/agents/unit-magpie-0/.venv/lib/python3.8/site-packages/charms/reactive/bus.py", line 390, in dispatch
    _invoke(other_handlers)
  File "/var/lib/juju/agents/unit-magpie-0/.venv/lib/python3.8/site-packages/charms/reactive/bus.py", line 359, in _invoke
    handler.invoke()
  File "/var/lib/juju/agents/unit-magpie-0/.venv/lib/python3.8/site-packages/charms/reactive/bus.py", line 181, in invoke
    self._action(*args)
  File "/var/lib/juju/agents/unit-magpie-0/charm/reactive/magpie.py", line 135, in check_all_node
    _set_states(check_nodes(nodes))
  File "/var/lib/juju/agents/unit-magpie-0/charm/lib/charms/layer/magpie_tools.py", line 623, in check_nodes
    link_speed = get_link_speed(primary_iface)
  File "/var/lib/juju/agents/unit-magpie-0/charm/lib/charms/layer/magpie_tools.py", line 609, in get_link_speed
    return int(f.read())
OSError: [Errno 22] Invalid argument

And sure enough:
$ cat /sys/class/net/br-enp5s0/speed
cat: /sys/class/net/br-enp5s0/speed: Invalid argument

The charm code should probably be updated to gracefully handle this situation.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/charm-magpie/+/858862

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/charm-magpie/+/858862
Committed: https://opendev.org/openstack/charm-magpie/commit/921ea2d4520364aa2386fdecd6f94368c96e4855
Submitter: "Zuul (22348)"
Branch: master

commit 921ea2d4520364aa2386fdecd6f94368c96e4855
Author: Frode Nordahl <email address hidden>
Date: Thu Sep 22 10:27:15 2022 +0200

    Gracefully handle Invalid argument from /sys/.../speed

    Not all interfaces support retrieval of link speed through sysfs,
    gracefully handle those that don't.

    Closes-Bug: #1990481
    Change-Id: I2f43cd67bab52704c80da569912b7770f4c1877b