A workflow action that deletes images from the GitHub Container Registry (ghcr.io). Its primary focus is on supporting multi-architecture container images.
It includes the following features:
- Automatic GitHub user/organization repository support
- Deleting images by tag names
- Deleting untagged images
- Keeping a number of untagged images
- Keeping a number of tagged images
- Untagging of multi-tagged images
- Multiple package execution
- Referrers/GitHub attestation support (OCIv1 tag approach)
- Sigstore cosign support
- Retry and throttle support for the GitHub API calls
- Validation mode to verify multi-architecture & referrers images
To allow the injected GITHUB_TOKEN secret to have access to delete images it requires its permissions to have been set correctly, either by:
-
In the GitHub site, Settings > Actions > General, set the Workflow permissions option to "Read and write permissions".
-
or by setting the permissions directly in the workflow by setting the packages value to write.
jobs: delete-untagged-images: name: Delete Untagged Images runs-on: ubuntu-latest permissions: packages: write
The most basic setup with no delete or keep options deletes all untagged images from the repository. Untagged here means a top-level container image, not the underlying parts of a multi-architecture image (which also appear as untagged packages).
To get started add an action definition to a workflow file.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
dry-run: true
token: ${{ secrets.GITHUB_TOKEN }}
The action calls both the registry API (ghcr.io) and the GitHub package API to facilitate support for multi-architecture images. This is required to determine the relationships between all of the multi-architecture image contents. It downloads the manifest descriptors of all images and maps their content to the underlying packages. Which for multi-architecture images the underlying packages appear as untagged in GitHub (as seen in the web interface). To safely delete untagged images the action determines first if the untagged package is actually in use by another image/package and skips these. Likewise to delete an image it needs to delete all of the underlying packages.
It's recommended to test the cleanup action first by setting the dry-run: true
option on the action and then reviewing the workflow log. This mode will
simulate the cleanup action but will not delete any images/packages. This is
especially important when using a wildcard/regular expression syntaxes or the
older-than
option to select images.
The high level processing of the action occurs as follows:
- For each package.
- Download all package metadata and their manifests and put them into a working 'filter set'.
- Remove all child images from the working filter set (including referrers and cosign images).
- Remove
exclude-tags
images from filter set. - Remove images which are younger than the
older-than
option from the filter set. - Stage for deletion
delete-tags
images present in the filter set. - Stage for deletion
delete-ghost-images
,delete-partial-iamges
anddelete-orphaned-images
images present in the filter set. - Process
keep-n-tagged
images from the filter set, stage remainder tagged images for deletion. - Process
keep-n-untagged
images from the filter set, stage remainder untagged images for deletion. - Or process
delete-untagged
, staging all untagged images in filter set for deletion. - Preform the deletion on all staged packages, including their children if present.
Option | Required | Defaults | Description |
---|---|---|---|
token | yes | Token used to connect with ghcr.io and the Package API | |
owner | no | project owner | The GitHub repository owner, can be an organization or user type |
repository | no | repository name | The GitHub repository name |
package(s) | no | repository name | Comma-separated list of packages to cleanup. Supports dynamic packages (wildcard or regular expression) by enabling the expand-packages option. Can be used as package or packages |
expand-packages | no | false | Enable wildcard or regular expression support on the package(s) option to support dynamic package selection. It requires use of a Personal Access Token (PAT) for the token value. |
If the owner, repository or package options are not set then the values are automatically set from the project environment where the action is running.
Option | Required | Defaults | Description |
---|---|---|---|
delete-tags | no | Comma-separated list of tags to delete (supports wildcard syntax), can be abbreviated as tags . A regular expression selector can be used instead by setting the use-regex option to true |
|
exclude-tags | no | Comma-separated list of tags strictly to be preserved/excluded from deletion (supports wildcard syntax). A regular expression selector can be used instead by setting the use-regex option to true |
|
delete-untagged | no | depends* | Delete all untagged images |
keep-n-untagged | no | Number of untagged images to keep, sorted by date, keeping the latest | |
keep-n-tagged | no | Number of tagged images to keep, sorted by date, keeping the latest | |
delete-ghost-images | no | false | Delete multi-architecture images where all underlying platform images are missing |
delete-partial-images | no | false | Delete multi-architecture images where some (but not all) underlying platform images are missing |
delete-orphaned-images | no | false | Delete tagged images which have no parent (e.g. referrers and cosign tags missing their parent) |
older-than | no | Only include images for processing that are older than this interval (eg 5 days, 6 months or 1 year) |
* If no delete or keep options are set on the action then the action defaults
the option delete-untagged
to "true" and will delete all untagged images.
Option | Required | Defaults | Description |
---|---|---|---|
use-regex | no | false | If set to true, the delete-tags ,exclude-tags and package options expect a regular expression selector (if they are set) |
dry-run | no | false | Simulate a cleanup action but does not make any changes (true/false) |
validate | no | false | Validate all multi-architecture images in the registry after cleanup |
log-level | no | info | The log level (error/warn/info/debug) |
Comma-separated list of tags to delete (supports a wildcard syntax). Can be
abbreviated as tags
. Use this option to delete specific tags in the package
repository.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
delete-tags: mytag*,dev # same as tags: mytag*,dev
token: ${{ secrets.GITHUB_TOKEN }}
If a tag to be deleted links to an image with multiple tags the action will unlink the tag before is deleted, effectively untagging the image. But the underlying image will not be deleted (unless all of its additional tags have been deleted also).
The option can make use of a simple wildcard syntax to match multiple images. See the wildcard-match project for its syntax. It supports the ?, * and ** wildcard characters.
To use a regular expression instead of a comma-seperated list set the
use-regex
option to true.
This option deletes all untagged images from package repository. It is the same
as the default mode, however, this option can be combined with any of the other
options (except for the keep-n-untagged
).
Note: Untagged here means untagged images not untagged packages (in GitHub). So after running this option on repositories with multi-architecture images there could still be untagged packages showing in GitHub.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
delete-untagged: true
token: ${{ secrets.GITHUB_TOKEN }}
This option is used to exclude tagged images from being deleted. Use it to exclude tags when combined with other options. It takes priority over all other options.
The option can make use of a simple wildcard syntax to match multiple images. See the wildcard-match project for its syntax. It supports the ?, * and ** wildcard characters.
To use a regular expression instead of a comma-seperated list set the
use-regex
option to true.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
exclude-tags: dev,latest,pr*
keep-n-tagged: 10
token: ${{ secrets.GITHUB_TOKEN }}
To limit the action to images that are older than a certain time this setting can be used. Set this option to a relative date value from now. This option can be used with all of the delete and keep options narrowing their scope to which images they will process.
The syntax supports the following units in the plural and singular forms: seconds, minutes, hours, days, weeks, months and years.
The option uses a simple human-interval syntax to match images. See the human-interval project for more information.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
older-than: 1 year
keep-n-tagged: 10
token: ${{ secrets.GITHUB_TOKEN }}
These options clean up invalid multi-architecture images. They are intended to
assist in cleaning up repositories that have been corrupted. Use the validate
option first to identify the images which are not valid.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
delete-ghost-images: true
token: ${{ secrets.GITHUB_TOKEN }}
This option removes tagged images where the assoicated parent image does not exist. It searches for images with tags starting with "sha256-" and then searches for the equivalent sha256: digest. If an image digest is not found then its flagged for deletion. This picks up orphaned referrers and cosign images.
Includes for deletion all untagged images but excludes (keeps) a number of them.
The value of this option sets the number of untagged images to keep. Untagged
images are sorted by date and the most recent untagged images are kept. May be
combined with other delete options (except the delete-untagged
option).
Note: Untagged here means untagged images not untagged packages in GitHub.
jobs:
- name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
keep-n-untagged: 3
token: ${{ secrets.GITHUB_TOKEN }}
Setting keep-n-untagged
to 0 has the same effect as setting the
delete-untagged
option to true, deleting all untagged images.
Includes for deletion all tagged images but excludes (keeps) a number of them. The value of this option sets the number of tagged images to keep. Tagged images are sorted by date and the most recent tagged images are kept. May be combined with other delete options.
jobs:
- name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
keep-n-tagged: 3
token: ${{ secrets.GITHUB_TOKEN }}
This option operates on all tagged entries. To narrow it's scope use the
exclude-tag
option also.
The default injected token (secret.GITHUB_TOKEN
) is sufficient for packages
which have been created by a repository project pipeline (or the package has
been setup to grant admin access to it). For setups where the action is
accessing a package in a different repository or dynamic package selection is
being used (expand-packages
is set to true) a Personal Access Token (PAT) is
required for the token
.
The PAT should be setup as a Classic token. This is due to the GitGub Registry
API currently only supporting Classic tokens. The token should be setup with
both write:packages
and delete:packages
scopes.
The package
(or packages
) options can be set to a comma separated list of
packages to operate on.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
packages: myimage1,myimage2
token: ${{ secrets.GITHUB_TOKEN }}
To utilize a wildcard set the expand-packages
option to true and utilize a PAT
for the token.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
packages: myimage*,someotherimage
expand-packages: true
token: ${{ secrets.GHCR_PAT }}
A regular expression can be used alternatively. This requires the use-regex
option to be set to true.
jobs:
- name: ghcr.io cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
packages: '^myimage[12]$'
expand-packages: true
use-regex: true
token: ${{ secrets.GHCR_PAT }}
Multiple package execution can also be achived by using the GitHub workflow matrix mechanism.
Simulates how to keep 10 tagged images as well as the dev image. Additionally deletes all untagged images. Also removes multi-arch containers that are missing some or all underlying packages.
jobs:
- name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- name: 'Clean up docker images'
uses: dataaxiom/ghcr-cleanup-action@v1
with:
dry-run: true
keep-n-tagged: 10
exclude-tags: dev
delete-untagged: true
delete-partial-images: true
token: ${{ secrets.GITHUB_TOKEN }}
This sample operates on multiple packages and makes use of a regular expression selector. It excludes all versioned images and the latest and main tags from processing.
cleanup-images:
name: cleanup-images
runs-on: ubuntu-latest
concurrency:
group: cleanup-images
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
packages: 'tiecd/k8s,tiecd/okd,tiecd/gke,tiecd/eks,tiecd/aks,tiecd/node18,tiecd/node20'
delete-untagged: true
keep-n-tagged: 3
exclude-tags: "^\\d+\\.\\d+\\.\\d+$|^latest$|^main$"
use-regex: true
token: ${{ secrets.GITHUB_TOKEN }}
name: Cleanup Pull Request Images
on:
pull_request:
types: [closed]
jobs:
ghcr-cleanup-image:
name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- name: Delete image
uses: dataaxiom/ghcr-cleanup-action@v1
with:
delete-tags: pr-${{github.event.pull_request.number}}
token: ${{ secrets.GITHUB_TOKEN }}
name: Daily Image Cleanup
on:
# every day at 01:30am
schedule:
- cron: '30 1 * * *'
# or manually
workflow_dispatch:
jobs:
ghcr-cleanup-image:
name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
token: ${{ secrets.GITHUB_TOKEN }}
The default settings will use the current project to determine the owner, repository and package names but for cross-project and multiple package support these can be overridden by setting the owner, repository and package options.
The example below uses a regular expression as the selector for the
delete-tags
option.
jobs:
- name: ghcr cleanup action
runs-on: ubuntu-latest
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
owner: dataaxiom
repository: tiecd
package: tiecd
token: ${{ secrets.GITHUB_TOKEN }}
delete-tags: '^mytag[12]$'
use-regex: true
To ensure the integrity of all images in the package repository all of of the image manifests are required to be downloaded and cross-referenced each time the action is run. The effect of this is that it will increase the package download count showing in GitHub for all packages by one. The action does not download the underlying package itself, just the manifests. But GitHub uses that event to mark it as a download.
The action is not designed to be run in parallel on the same package repository. Due to the nature of the cleanup process and determining what can be safely deleted it requires that no other package publishing or deleting process is occurring at the same time. It's recommended to use a GitHub concurrency group with this action in complex/busy repositories.
cleanup-images:
name: cleanup-images
runs-on: ubuntu-latest
concurrency:
group: cleanup-images
steps:
- uses: dataaxiom/ghcr-cleanup-action@v1
with:
token: ${{ secrets.GITHUB_TOKEN }}
Set the validate
option to true to enable a full scan of the image repository
at the end of the execution to check that all multi-architecture images have no
missing platform images. Warnings will be outputted if there are missing
packages.
GitHub has a package restoration API capability. The package IDs are printed in the workflow log where the ghcr-cleanup-action is run.