~"frontend-weight::1" ~"backend-weight::1" ### Problem to solve Currently, in the container expiration policies, there is no way to express something such as "no matter what, don't delete this tag". This introduces risk into the deletion process, as it's possible to delete `release` or `master` images. ### Intended users <!-- Who will use this feature? If known, include any of the following: types of users (e.g. Developer), personas, or specific company roles (e.g. Release Manager). It's okay to write "Unknown" and fill this field in later. * [Sasha (Software Developer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sasha-software-developer) * [Devon (DevOps Engineer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#devon-devops-engineer) * [Sidney (Systems Administrator)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sidney-systems-administrator) Personas are described at https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/ --> ### Proposal * Add the `name_regex_keep` as an option to the container expiration policies. * Rename the existing column `name_regex` to `name_regex_delete` to match the updates made in the [bulk delete api](#27072) * The default value for `name_regex_keep` for a policy will be NULL or blank, this will go into effect for existing policies. * `name_regex_keep` will be optional * Update the documentation to demonstrate how to use the feature. #### UI  ### Permissions and Security There are no changes to permissions and no immediate security impact. ### Documentation The [container expiration policy docs](https://docs.gitlab.com/ee/user/packages/container_registry/#managing-project-expiration-policy-through-the-ui) will be updated showing the new option with details on how it works. ### What does success look like, and how can we measure that? * We can set a retention regex on an expiration policy specifying a pattern of tags that must not be deleted for that policy. ### Links / references Bulk Delete API issue that added the new param to the cleanup service. https://gitlab.com/gitlab-org/gitlab/issues/27072