Write an integration test for GH: #780

[Dan Watkins]

The code in https://github.com/canonical/cloud-init/pull/780 is in need of an integration test. Let's use this as a place to hash out the design of it and any framework changes, instead of the comments of a soon-to-be-landed PR.

[Dan Watkins (oddbloke)]

In #780, I mentioned some framework changes would be required. Specifically, I think we want to introduce a new mark[0] which allows us to configure the SSH keys that will be passed to the instance under test. An example of the introduction of a new mark is [1]: you can see that it uses `getter` to fetch the "lxd_config_dict" mark and then, with a cloud-specific guard, sets it in `launch_kwargs` (which is then passed to pycloudlib, our cloud library).

This would be similar, but would set `vm_params` in `launch_kwargs`: the provided `vm_params` is merged over the default config in [2] (so, yes, you're going to pass in a very deeply-nested dict): we can use that to pass in our non-standard key material. An important assumption by me here is that putting the non-standard key material here means that it will be presented to instances in a way that triggers this bug: please do confirm that!

I'm finishing my day here, please do ask follow-up questions: here or, as always, in #cloud-init!

[0] https://docs.pytest.org/en/stable/example/markers.html#mark-examples
[1] https://github.com/canonical/cloud-init/commit/05216aa37e1fad32433dbea102dc3ceae7d8565d#diff-fa8021f7704bd878dc75be40d940098cdc52657607b02fe6bf3acac60ff10694
[2] https://github.com/canonical/pycloudlib/blob/main/pycloudlib/azure/cloud.py#L337-L345

[shixuantong (sxt1001)]

https://github.com/canonical/cloud-init/pull/865

[shixuantong (sxt1001)]

The problem seems to have been resolved，we can close it.

[James Falcon (falcojr)]

Where do you think it is resolved? This is an issue about writing a test. I'm not sure we have the coverage requested here.

[James Falcon (falcojr)]

Tracked in Github Issues as https://github.com/canonical/cloud-init/issues/3866