Renovate is not displaying changelog for helm charts using OCI, while it's working with helm repository

[n0rad]

How are you running Renovate?

Mend Renovate hosted app on github.com

Was this something which used to work for you, and then stopped?

I am trying to get this working for the first time

Describe the problem

When you declare a dependency in an helm chart using OCI repository, instead of helm repository, renovate is able to propose update but do not display the changelog.

I created an example to reproduce the issue here

The chart.yaml is declared using a dependency from an helm repository. The PR is displaying the changelog (in the history of the PR description).

Then I switched the registry in the charts.yaml to an oci image. This chart was fetch from the helm repository, and pushed to docker hub using helm 3.12.0, so the oci image contains opencontainers annotations.

it look like renovate is able to find the org.opencontainers.image.url and tries to fetch the changelog looking at the logs:

DEBUG: Fetching changelog: https://github.com/argoproj/argo-helm (5.50.0 -> 5.51.0) (branch="renovate/argo-cd-5.x")

but nothing is displayed in the PR.

[rarkins]

Looks like the releases are prefixed and renovate doesn't match them. Not helm specific if so

[n0rad]

I was actually doing tests to figure out if renovate is able to understand the release prefix in case of multitenant repositories, while i discovered this issue.
Note that with an helm repository, it's finding the release, even if it's prefixed.

[usmonster]

💁 Regarding this topic, I've opened #29943.

[n0rad]

@rarkins could you review your assumption? because to me the problem looks small and unrelated to the prefix.

It's working fine when using an helm repository (even if there is a prefix).
It's finding the repository and trigger the changelog fetch when using a OCI repository, but do not get into displaying it.

[viceice]

I think we should use the platform for changelog source url to retrieve versions (eg github-tags) instead of using the source datasource (eg docker).

@rarkins @secustor WDYT?

[secustor]

Wouldn't drop supporting having Changelog files on generic endpoints? Something like https://myexample.com/foo/bar/Changelog.md which then return the raw file as text.

[viceice]

no, it shouldn't. we are already in platform dependent code, so we know we're on GitHub and know the repo, but then we call datasource getReleases with original dependency to fetch all versions instead directly use github-tags. we use github-tags later to fetch release notes with only known versions

[usmonster]

This sounds like a good solution (though still not sure why it works for other OCI Helm charts); would a PR be welcome for this / can an issue be generated?

In the meantime, do you see a workaround to force the datasource used in this case? I've thought about using a custom datasource, but I suspect it might break other things and have an effect not limited to the changelog generation part.

Thanks again!

[viceice]

• Missing Changelogs / changelog version retrieval change #29687