doc: improve integrations testing configuration instructions

[a-dubs]

Proposed Commit Message

docs: improve integrations testing configuration instructions

Merge type

• Squash merge using "Proposed Commit Message"
• Rebase and merge unique commits. Requires commit messages per-commit each referencing the pull request number (#<PR_NUM>)

[TheRealFalcon]

Some great updates here, thanks! I left some comments inline. Additionally, there are a few things you didn't write, but when reading the page, I noticed should be updated.

Platform-specific marks can be used to limit tests to particular platforms. This is no longer true. Can we remove it? Related, would you be able to add a section about skipping tests by platform or OS? We used to use marks for this, but that got really complicated, so now we use @pytest.mark.skipif(...) with things imported from releases.py.

E.g.,

from tests.integration_tests.releases import CURRENT_RELEASE, NOBLE
...
@pytest.mark.skipif(CURRENT_RELEASE < NOBLE, reason="blah blah blah")
...

Also, in the image selection section, <image_id>[::<os>[::<release>]] should now be <image_id>[::<os>::<release>::<version>].

[TheRealFalcon]

I'm not sure we need 3 separate examples here showing how to run a test. One of the benefits of using pytest and tox is that things "just work" like they do for any other pytest or tox project. I think one example here would suffice with perhaps a link to https://docs.pytest.org/en/7.1.x/how-to/usage.html

[a-dubs]

Hmm... I might be swayed by this, but still think it is worth directly calling out, because I think specifying a path is one of the most common use cases for integration tests. Rarely will a new contributor be running the entire integrations sweet due to the insanely long run time?

Let me see how this looks in tabular form so it takes up less space and maybe this will feel less like a waste of space.

[a-dubs]

So worst comes to worst, I agree, 3 different examples is not necessary and just one command showing how to specify a path would suffice.

[a-dubs]

Platform-specific marks can be used to limit tests to particular platforms. This is no longer true.

@TheRealFalcon Would you be able to elaborate what you mean by this?

Isn't the following an example of this in action?
https://github.com/canonical/cloud-init/blob/779dd6b009f8a568fe74e98df9803ad590b83044/tests/integration_tests/datasources/test_ec2_ipv6.py#L22C1-L22C70

Once I have some clarity on this, I agree that it would be valuable to expand further on how to develop new integration tests / modify existing ones. (this is actually my next documentation task)

[TheRealFalcon]

@TheRealFalcon Would you be able to elaborate what you mean by this?

See this example from 22.3. We now just use skipif instead of individual marks.

[TheRealFalcon]

Two more minor things I saw on another read through, and then we should be good!

[a-dubs]

@TheRealFalcon made all changes as requested. hopefully this is good to go!

[TheRealFalcon]

Whoops, a t got added Amazon EC2. After this one we should be really actually for sure good 😉

[a-dubs]

haha great catch. thanks @TheRealFalcon !