GitHub Container registry cleaning action

GitHub action allowing to clean a GitHub Container registry by deleting the unnecessary images and image indices. Unnecessary can mean:

• untagged images not referenced by any image index
• untagged image indices and their referenced images
• tagged images related to a closed Pull Request
• tagged image indices related to a closed Pull Request and their referenced images

There are actually many possible combinations, for a list of all the managed cases see the unit tests.

Basic usage

uses: pcasteran/ghcr-cleaning-action@v1
with:
  user: ${{ github.repository_owner }}
  password: ${{ secrets.YOUR_SECRET_PAT }}
  package: terraform-graph-beautifier
  repository: pcasteran/terraform-graph-beautifier
  dry-run: true

The input dry-run is set to true in the sample above to let you test the behavior of the action and configure it to your needs without actually deleting objects from your registry.

Inputs

Name	Type	Required	Description
registry	String	No	The URL of the container registry. Defaults to ghcr.io.
user	String	No	The container registry user. Defaults to ${{ github.repository_owner }}.
password	String	Yes	The container registry user password or access token. See the authentication section
package	String	Yes	The name of the package to clean.
repository	String	No	The GitHub repository (format owner/repository) in which to check the pull requests statuses. Defaults to ${{ github.repository }}.
pr-tag-regex	String	No	The regular expression used to match the pull request tags, must include one capture group for the PR id. Defaults to ^pr-(\\d+).*.
dry-run	Bool	No	If true, compute everything but do no perform the deletion. Defaults to false.
debug	Bool	No	Enable the debug logs. Defaults to false.

Outputs

This action does not output any value.

Authentication

As per the documentation, the authentication to the GHCR registry must be done using a personal access token. Only classic tokens can be used, fined-grained ones are currently (2023-01) not supported.

The recommendation is to create a new PAT with only the read:packages and delete:packages scopes. To do so, you can use this link.