Build all Kubernetes versions available. Fix for https://github.com/flatcar/Flatcar/issues/1293

[jhaprins]

[Title: describe the change in one sentence]

Modify the workflow file to download information about available Kubernetes versions and build all raw images for the last maintenance release for every main release.

How to use

[ describe what reviewers need to do in order to validate this PR ]

Testing done

[Describe the testing you have done before submitting this PR. Please include both the commands you issued as well as the output you got.]

• I created a fork of this project
• I then did the changes needed for the workflow file to create desired outcome.
• I pushed my changes to github to see if it would result in the images I want to have.

[pothos]

Thanks, we need to move the curl call into it's own line for error handling (i.e., K8S_VERS=$(curl …)), and also add some common curl options for robustness: -fsSL --retry-delay 1 --retry 60 --retry-connrefused --retry-max-time 60 --connect-timeout 20

I think we also need to filter out future targetDate entries, or?

[jhaprins]

I have done the following additional changes:

• I moved the curl call outside of the array
• I added the curl options you requested.
• I check if the resulting string is not empty
• If the string is empty I bail out with an error 1
• I create the array of kubernetes versions
• I add this array to the images array
• The yq command already does select the correct versions.

Jan Hugo Prins

[pothos]

Suggested change

	images+=(${KBS_VERS_ARRAY[@]})
	images+=("${KBS_VERS_ARRAY[@]}")

[jhaprins]

Agreed. Will modify.

[pothos]

Suggested change

	[[ -z "${KBS_VERS}" ]] && exit 1
	if [[ -z "${KBS_VERS}" ]]; then; echo "Failed fetching Kubernetes versions"; exit 1; fi

[jhaprins]

Don't really like that if construct. I will make it a little different, but functional the same.
I hope you will agree.

Suggested change

	[[ -z "${KBS_VERS}" ]] && exit 1
	[[ -z "${KBS_VERS}" ]] && echo "Failed fetching Kubernetes versions" && exit 1

[pothos]

I think we also need to filter out future targetDate entries, or?

With that I meant that while the current entries have no future dates that might be the case and then the k8s version can't be downloaded because it's not released yet.

[jhaprins]

With that I meant that while the current entries have no future dates that might be the case and then the k8s version can't be downloaded because it's not released yet.

No, this is not true.
Check for example 1.29.1, this one has a future date but is not included in my selection.
The jq selection rule fetches very specific previousPatches, and therefor it will not fail on next: patches which are not release yet. See: yq -r '.schedules[].previousPatches[0].release'