Epic Goal

• Allow for more granular auto-pruning policies to target only certain image tags

Why is this important?

• It is a common practice to version containerized software using image tags in a single repository and as such these repositories hold multiple version lines of the software (e.g. 2.x, 3.x, 4.x) but also images that resemble release candidates or nightly builds. Some customers also leverage tag naming pattern convention to denote images that are ready for production environments (eg. prod-..., stable-..., dev-...)
  With today's auto-pruning policies it is not possible to target or exclude these image tags and the current policies are therefore perceived as too coarse.

Scenarios

1. See acceptance criteria

Acceptance Criteria

• for organization-level and repo-level policies, allow to specify a regular expression to match a subset of tags for both existing policy types (tag amount, tag age)
• The expression should be optional and if left blank should be evaluated as "matching all images"
• the regular expression is user-supplied and needs to be protected against ReDOS attacks
• when updating to the Quay version implementing tag pattern support, existing policies should not be changed
• the registry-wide policy does not need that to support tag naming patterns at this point
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Dependencies (internal and external)

1. ...

Previous Work (Optional):

1. https://issues.redhat.com/browse/PROJQUAY-6140

Open questions::

1. …

Done Checklist

• CI - CI is running, tests are automated and merged.
• Release Enablement <link to Feature Enablement Presentation>
• DEV - Upstream code and tests merged: <link to meaningful PR or GitHub Issue>
• DEV - Upstream documentation merged: <link to meaningful PR or GitHub Issue>
• DEV - Downstream build attached to advisory: <link to errata>
• QE - Test plans in Polarion: <link or reference to Polarion>
• QE - Automated tests merged: <link or reference to automated tests>
• DOC - Downstream documentation merged: <link to meaningful PR>