Alert admin that untagged images are ready for deletion (removal from storage)
Problem to solve
The GitLab Container Registry allows developers to build, push and share Docker images/tags using the Docker client and/or GitLab CI/CD.
For organizations that build many images across many projects, it is important to regularly remove old, unused images and tags. However, many users do not know that after they remove an image via the Container Registry UI that they are NOT deleted from storage.
This is problematic for self-managed customers that are surprised by storage costs for the Container Registry.
Intended users
Further details
Self-managed vs gitlab.com
Since GitLab.com users can not run garbage collection, this feature should be for self-managed users only. The goal of this issue will be to alert admin at self-managed instances that there are multiple steps required to remove unreferenced images from storage.
Proposal
When an Admin (self-managed instances only) deletes an image(s) from the Container Registry UI, alert them that the image is ready for deletion and that they should run garbage collection to remove it from storage.
Permissions and Security
- There are no permissions changes required for this issue.
Documentation
- There are no documentation changes required for this change.
What does success look like, and how can we measure that?
- Success looks like self-managed instance owners are aware that in order to delete an image from storage, it must be both untagged and deleted via garbage collection.