Accept nested namespaces in spacewalk.api

[agraul]

What does this PR do?

salt-run $server spacewalk.api allows users to run arbitrary Spacewalk API functions through Salt. These are passed in a namespace.method notation and may use nested namespaces. Previously only methods in a top-level namespace were supported.

What issues does this PR fix or reference?

Fixes: #57442

Previous Behavior

Exception occurred in runner spacewalk.api: Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/salt/client/mixins.py", line 377, in low
    data['return'] = func(*args, **kwargs)
  File "/usr/lib/python3.6/site-packages/salt/runners/spacewalk.py", line 175, in api
    namespace, method = command.split('.')
ValueError: too many values to unpack (expected 2)

New Behavior

API gets called as expected, e.g.

channel.software.listChildren ('sle-product-sles15-sp1-pool-x86_64',):
    |_
      ----------
      arch_label:
          channel-x86_64
      arch_name:
          x86_64
[...]

Merge requirements satisfied?

• Docs
• Changelog - https://docs.saltstack.com/en/master/topics/development/changelog.html
• Tests written/updated

Does this need to be documented in addition to the changelog? As there are no spacewalk runner tests yet I will need some time writing them, I opened the PR already to get feedback on the fix.

Commits signed with GPG?

Yes

[Akm0d]

@agraul Thank you for opening a PR so quickly! Let me or @waynew know if you need help with writing the tests

[waynew]

An odd failure on centos happening here - I've asked the team if they've seen anything. I guess I can kick these off again and see if it was just an infrastructure thing

[agraul]

I'll push the tests on Tuesday (Monday is a public holiday where I live), I have something that works but I want to clean it up a little.

[agraul]

Tests are there now, I got a pylint warning for the test:

tests/unit/runners/test_spacewalk.py:1: [W9903(no-encoding-in-file), ] PEP263: Use UTF-8 file encoding

With Python3 this can be left out in my opinion (with UTF-8 being the default), but I am not sure if this is an oversight w.r.t. the pylintrc or you want to keep it even for a Python3-only codebase. Let me know if I should add it.

[waynew]

It's probably easiest for now to just go ahead and add the encoding line.

If we change it, it'll just be one more file for sed or awk to change. And that's the only thing that looks to need any changes here 👍

[agraul]

I've added the line, thanks for your review @waynew

[waynew]

🚀