GitLab Registry "Remove docker image from registry when branch is merged"

Problem to solve

When merging a branch the 'Remove branch after merge' checkbox is available, however I would like Docker images that were used in the merge branch also to be removed (untagged) after a merge, or the option to do so.

Target audience

Registry operators

Further details

Using available examples for GitLab Runner integration with the Registry we push images the registry like this:

CONTAINER_TEST_IMAGE: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG

This creates a docker image with the branch name in the registry, but after merging I would love to see this cleaned up.

Proposal

Provide the option to remove Docker images from the registry, given that the image was tagged/pushed based on the branch name.

Documentation

n/a

What does success look like, and how can we measure that?

n/a

Links / references

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