Plankton is a commandline interface for private Docker Registries (v2). It supports the anonymous usage as well as the HTTP Basic and Token Authentication. With the help of Plankton you can interact with tags (list, get details, remove, cleanup with keep n latest). It is great for automating CI/CD deployments and save memory at the end.

• Installation
  • Local
  • Docker
• Usage
  • Environment
  • Listing tags
  • Tag details
  • Delete a tag
  • Cleanup tags
  • Gitlab CI
• Development
• Contributing
• License
• Code of Conduct

Install it yourself as:

$ gem install plankton

There is a Docker image available as jack12816/plankton. Just pull it and use it like that:

# Pull the latest Plankton version
$ docker pull jack12816/plankton
# Ask Plankton for help
$ docker run --rm jack12816/plankton help
# Use Plankton even with environment variables
$ docker run --rm \
    -e REGISTRY_CLI_HOSTNAME=your.registry.tld \
    jack12816/plankton tags

You can pass --hostname, --username and --password commandline options to Plankton or use the following environment variables:

export REGISTRY_CLI_HOSTNAME=
export REGISTRY_CLI_USERNAME=
export REGISTRY_CLI_PASSWORD=

The commandline options take precedence over the environment variables.

You can list all tags of a given repository at your Docker Registry. By default it will print some handy details (created at date (ISO 8601), layer size). If you do not care about these additional information or you want to speed up the command, just disable them by passing the --no-details option.

Usage:
  plankton tags REPO

Options:
  -l, [--limit=N]                  # How many tags to fetch (maximum)
                                   # Default: 20
  -d, [--details], [--no-details]  # Display details (created at date, full layer size)
                                   # Default: true

A common output looks like this:

$ plankton tags apps/fancy

Image tag Created at                Size
1.3.0     2017-09-24T16:36:00+00:00 273.27 MiB
1.2.1     2017-09-24T16:32:56+00:00 273.27 MiB
1.2.0     2017-09-24T16:31:53+00:00 273.27 MiB
1.1.0     2017-09-24T16:31:12+00:00 273.27 MiB

The tags are ordered to show the latest created first.

With the help of Plankton it is easy to retreive some details about a tag. Just specify the repository and the tag name and you will get something like this:

Usage:
  plankton tag REPO TAG

$ plankton tag apps/fancy 1.0.0

Tag: 1.0.0
Digest: sha256:4fdcb19e157a55eaf1254ef9923216127cb95560b9c0a6e94ae48ac2cefb6674
Created at: 2017-09-24T16:36:00+00:00
Layers: 8
 sha256:d93a2d7cc901177e87182b2003d50fb3ffd5be3eb698f39f5c862264efe6ee99 (50.16 MiB)
 sha256:15a33158a1367c7c4103c89ae66e8f4fdec4ada6a39d4648cf254b32296d6668 (18.37 MiB)
 sha256:f67323742a64d3540e24632f6d77dfb02e72301c00d1e9a3c28e0ef15478fff9 (41.23 MiB)
 sha256:c4b45e832c38de44fbab83d5fcf9cbf66d069a51e6462d89ccc050051f25926d (128.45 MiB)
 sha256:c1d1736737e7ea666709bec11741051fbba7c8f896d17570c82c978413cb3312 (205.00 B)
 sha256:f3fd5681b6bafafd7d45041c29f1df202777ca906f7f01db58556feb177e6dfc (34.42 MiB)
 sha256:ac9eb90ae6f5320100f26741b82ae30d40c407b1f6d0a4974da70bd67da9ab74 (661.22 KiB)
 sha256:aa1e7b8285a7a366476ba71fdfb27b13712415310a063a0c41283326f5aecdbf (164.00 B)
Total layer size: 273.27 MiB
Image:
 Author: Hermann Mayer <hermann.mayer92@gmail.com>
 Operating system: linux
 Architecture: amd64
 Docker version: 17.07.0-ce
Dockerfile:
 Steps: 22

The rmtag operation takes care of deleting a specific tag. This requires a Docker Registry with the enabled delete storage option. By default Plankton will ask you for interactive feedback to confirm the operation. You can make use of the --no-confirm option to overcome this on automated usage.

Usage:
  plankton rmtag REPO TAG

Options:
      [--confirm], [--no-confirm]  # User interaction is required
                                   # Default: true

$ plankton rmtag apps/fancy 1.1.0

Delete apps/fancy:1.1.0? [yes, no] yes
Tag 1.1.0 was successfully deleted.

The cleanup operation will delete all "old" tags from a repository. You can configure it to delete all the tags, or keep the last n tags. This requires a Docker Registry with the enabled delete storage option. By default Plankton will ask you for interactive feedback to confirm the operation. You can make use of the --no-confirm option to overcome this on automated usage. You can specify how many tags should stay by passing the --keep options. It defaults to 3.

Usage:
  plankton cleanup REPO

Options:
  -k, [--keep=N]                   # How many tags to keep
                                   # Default: 3
      [--confirm], [--no-confirm]  # User interaction is required
                                   # Default: true

A common output looks like this:

$ plankton cleanup apps/fancy

 Tags to keep: 3 (819.81 MiB)
Image tag Created at                Size
1.3.0     2017-09-24T16:36:00+00:00 273.27 MiB
1.2.1     2017-09-24T16:32:56+00:00 273.27 MiB
1.2.0     2017-09-24T16:31:53+00:00 273.27 MiB
1.1.0     2017-09-24T16:31:12+00:00 273.27 MiB

 Tags to delete: 1 (273.27 MiB)
Image tag Created at                Size
1.1.0     2017-09-24T16:31:12+00:00 273.27 MiB

     Registry: https://your.registry.tld
   Repository: apps/fancy
 Tags to keep: 3

Cleanup apps/fancy (1 tags)? [yes, no] yes

Deleted 1.1.0 (freed 273.27 MiB)

If you are interested in the usage of Plankton ontop of your Gitlab CI system, here comes a ready to use solution:

cleanup:
  image:
    name: jack12816/plankton
    entrypoint: ["/bin/sh", "-c"]
  variables:
    REGISTRY_CLI_HOSTNAME: your.registry.tld
    REGISTRY_CLI_USERNAME: gitlab-ci-token
    REGISTRY_CLI_PASSWORD: ${CI_JOB_TOKEN}
  script: plankton cleanup --keep 3 --no-confirm apps/fancy

Just use the Plankton operations as normal. Just setup some Gitlab CI stages to perform your operations in the correct order. (Something like build, test, publish, cleanup) The REGISTRY_CLI_USERNAME and REGISTRY_CLI_PASSWORD environment variables are correctly set if you use a Docker Registry which is authenticated by Gitlab. If you use a HTTP Basic Authentication, just set them accordingly.

Heads up! Unfortunately the cleanup actions are not permitted by Gitlab for the CI_JOB_TOKEN at the moment. You can work around this by following the instructions on the issue.

After checking out the repo, run make install to install dependencies. Then, run make test to run the tests. You can also run make shell for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/Jack12816/plankton. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the Plankton project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.