feat: support chart release-notes or changelog

[aabouzaid]

At the moment there is no way to set charts release-notes/changelog.

This PR adds an option to set the charts release-notes/changelog by looking for release-notes.md file.

• If the release-notes file is there, it will be used, if not, it will use the previous notion (Chart description), so no change in the behaviour.
• The user is responsible for generating the file, so the generating of the release notes is decoupled from the chart-releaser code.
• This PR should address the feature request in the issue no. Feature: Changelog #118
• If the feature is accepted, I will add the unit tests and update the docs.

[aabouzaid]

Hi @unguiculus @scottrigby
Could you please approve the CI workflow? And what do you think in general? Should I go with it?

[cpanato]

thanks for this PR, can you add some tests?

[aabouzaid]

@cpanato The unit tests and docs have been added.
Thanks.

[cpanato]

lgtm, just a comment that i think need to be empty and not a filename prefilled

[cpanato]

lgtm

[aabouzaid]

@cpanato that's great, thanks a lot 👍

[stevehipwell]

@aabouzaid looking at the code I can't see any logic to pick the correct notes out of a CHANGELOG, is this correct or have I missed something?

[aabouzaid]

@stevehipwell That's correct, it doesn't pick from a file, it uses the entire file (so that file should be single release notes, not the changelog that has all releases notes)

So whatever in the file will be used. The user is responsible to put what they need there.

Putting any logic to select from the file will couple chart-releaser with a certain format, and there are a lot of them there.

[stevehipwell]

@aabouzaid how would you expect this to work then? I guess a local workflow would be to copy part of your changelog to a temp file, but how would it work via automation?

Wouldn't picking a CHANGELOG format such as Keep a Changelog have been a better bet here? This would work with automation (specifically the GitHub action) and would also let you capture the Artifact Hub change annotations in index.yaml as part of the same process.

[chgl]

@stevehipwell as an example: I've implemented one approach here: https://github.com/chgl/charts/blob/master/.github/generate-chart-changelogs.sh where a changelog.md is generated from the chart.yaml's artifacthub annotations as part of the release process.

[stevehipwell]

@chgl the chart annotations are transient so not the best starting point. IMHO this would be best driven from a structured CHANGELOG.

[aabouzaid]

@stevehipwell Most if not all tools I saw that generates the CHANGELOG file are able to generate the changelog for a certain tag.

I use git-chglog with Keep a Changelog format, and here is how it generates the latest version release notes.

Also I use that file to update ArtifactHub annotation in the Chart.yaml file.

And as you can see from @chgl comment, everyone makes it differently, and adding the logic to chart-releaser will make it harder for many use cases.

[stevehipwell]

Thanks for your example @aabouzaid. However I think for generic use a workflow needs to work without needing to add repo commits. That said with a couple of small features added this could be supported with minimal additional steps and almost certainly work with the chart-releaser-action too.

• Allow --release-notes-file (I assume RELEASE_NOTES_FILE works) to be templated or set relative to chart
  • Either a dynamic or static CHANGELOG can be parsed using mindsers/changelog-reader-action to generate the file in CI
• Support merging annotations yaml file into index.yaml before push
  • Can use mindsers/changelog-reader-action to generate this file in CI
  • This wont break signing the chart artefact

[aabouzaid]

@stevehipwell it doesn't work that way, unfortunately. If you took a look at the code you will find that the upload command accesses the packaged charts not the source code of the charts.

In the current solution, you don't need to commit the release notes file to git but it should be in the Helm chart archive package (for the same reason, chart-releaser upload works the archived packages, not the source code).

Also, chart-releaser doesn't work with individual charts, it works with any charts in the working path (one or more, it doesn't matter) which means it's not possible to run external commands or Github Actions between each chart upload.

---

Here is how I do it with the new feature in this PR:
https://github.com/camunda-community-hub/camunda-helm/blob/15e81a3/.github/workflows/release.yaml

Job 1:

1. Generate the RELEASE-NOTES.md for each chart that will be released.
2. Stash the generated RELEASE-NOTES.md for all charts.

Job 2:

1. Unstash RELEASE-NOTES.md for all charts.
2. Run chart-releaser-action (which will run the whole chart-releaser cycle which includes: "package", "upload", "index" for all released charts).

[stevehipwell]

@aabouzaid I'm pretty sure that the Artifact Hub code supports annotations in the index as well as in the packaged chart.

I've automated my release markdown notes from a CHANGELOG.md in each chart directory without this feature. But it would be easier using this feature if it supported chart relative paths.