customChangelogUrl handlebar templating support

[gberche-orange]

I'd like to use a regexp capture group to programmatically construct a changelog url to a set of docker image packages, (such as https://hub.docker.com/r/crossplane/provider-gcp) such as:

    {
      "matchPackagePatterns": ["crossplane/(?<crossplanePackageName>[a-zA-Z0-9\\.\\-]*?)"],
      "customChangelogUrl": "https://github.com/crossplane-contrib/{{crossplanePackageName}}/"
    },

However, I see in the following traces logs:

DEBUG: Fetching changelog: https://github.com/crossplane-contrib/{{crossplanePackageName}}/ (v0.3.0 -> v0.4.1)(branch="renovate/crossplane-provider-kubernetes-0.x")

This makes me think that customChangelogUrl is not yet subject to templating (as suggested by https://docs.renovatebot.com/templates/#exposed-config-options

Is there another way to avoid duplicating the customChangeLogUrl for each crossplane-package (currently 63 packages) with syntax such as the following ?

    {
      "matchPackageNames": ["crossplane/provider-gcp"],
      "customChangelogUrl": "https://github.com/crossplane-contrib/provider-gcp/"
    },
    {
      "matchPackageNames": ["crossplane/provider-aws"],
      "customChangelogUrl": "https://github.com/crossplane-contrib/provider-aws/"
    },

Background:

I have a set of crossplane packages (K8S CR) that reference docker image dependencies who are lacking reference to source repo.

[viceice]

you can't use capture groups in an match pattern of package rules. they aren't stored anywhere.

you can use the replace template helper to get the name from depName value

[viceice]

🤔 are you sure customChangelogUrl is a templatable field? it seems it can only be used inside templates.

[gberche-orange]

that's what I was originally suspecting in this post #18280 (comment)

This makes me think that customChangelogUrl is not yet subject to templating (as suggested by https://docs.renovatebot.com/templates/#exposed-config-options

Would it make sense to make customChangelogUrl a templatable field ?

[viceice]

i don't think so. you can ask the docker image authors to include labels, so renovate can automatically find the source repos.

we've also a static list included inside renovate for some know packages to their repos

[gberche-orange]

thanks @viceice

I've submitted a suggestion to the crossplane community into crossplane/crossplane#3370 to add the OCI image label. This is likely to take time.

I've currently worked around the issue by duplicating the package rule for each package.

As usage of OCI images are rapidly increasing and the DockerFile reference does not yet make mention of the OCI label org.opencontainers.image.source, I believe this is quite common to have OCI images that can benefit from renovate PR but be missing changelog URL in their PRs.

It seems useful to me to provide a way for renovate package consumers to workaround lack of annotations for new communities leveraging OCI images. Make customChangelogUrl a templatable field seemed like a possible fix, there are certainly reasons why this does not seem a good idea.

[viceice]

it's documented here

https://docs.renovatebot.com/modules/datasource/#docker-datasource