gitlab-registry-cleanup 0.1.7
A tool to clean up untagged GitLab registry images.
License: MIT
Requires Python: ~=3.3
Keywords: Git,GitLab,Docker,Registry,Cleanup

GitLab-Registry-Cleanup
=======================

Introduction
------------

*GitLab-Registry-Cleanup* is a Python package for finding and (soft)
deleting untagged Docker images in a GitLab Docker registry. Currently
(April 2018), Docker registries only cleanup data if the removal of an
image is requested explicitly by the user. Therefore, **the registry
will keep on growing** if users only push new images. **Overwriting
existing tags is not sufficient** since images could be referenced by
their SHA256 hash by an external resource. This tool assumes that
untagged images are not needed any more and deletes them explicitly. It
can only be used for the embedded registry of a GitLab server.

**NOTE**: ``registry garbage-collect`` will have a ``-m`` flag in 2.7.0,
see `issue #1844 <https://github.com/docker/distribution/issues/1844>`__
and `pull request
#2302 <https://github.com/docker/distribution/pull/2302>`__.

Installation
------------

The latest version is available from PyPI and needs Python 3.3+:

.. code:: bash

   python3 -m pip install gitlab-registry-cleanup

This package can only be used on a GitLab server, since it needs read
access to the Docker registry files stored on disk. The script needs
root privileges, so either use the root account or the ``sudo`` utility.
The actual deletion of images is done via the GitLab web api to prevent
any data loss.

If you use the recommended operating system for GitLab (Ubuntu Server),
you can install Python 3 and ``pip`` with

.. code:: bash

   apt install python3-pip

if not already installed.

Usage
-----

Command Line Interface
~~~~~~~~~~~~~~~~~~~~~~

After installing with ``pip``, a ``gitlab-registry-cleanup`` command is
available:

::

   usage: gitlab-registry-cleanup [-h] [-g GITLAB_SERVER] [-r REGISTRY_SERVER]
                                  [-p LOCAL_REGISTRY_ROOT] [-c CREDENTIALS_FILE]
                                  [-u USERNAME] [-n] [-k] [-V]

   gitlab-registry-cleanup is a utility for cleaning up a GitLab registry by soft deleting untagged images.

   optional arguments:
     -h, --help            show this help message and exit
     -g GITLAB_SERVER, --gitlab-server GITLAB_SERVER
                           GitLab server hostname (for example `mygitlab.com`)
     -r REGISTRY_SERVER, --registry-server REGISTRY_SERVER
                           GitLab registry server hostname (for example
                           `registry.mygitlab.com`)
     -p LOCAL_REGISTRY_ROOT, --registry-path LOCAL_REGISTRY_ROOT
                           Path to the registry directory on the GitLab server
                           (default: /var/opt/gitlab/gitlab-
                           rails/shared/registry)
     -c CREDENTIALS_FILE, --credentials-file CREDENTIALS_FILE
                           path to a file containing username and password/access
                           token (on two separate lines)
     -u USERNAME, --user USERNAME
                           user account for querying the GitLab API (default:
                           root)
     -n, --dry-run         only print which images would be deleted
     -k, --insecure        allow insecure connections over plain HTTP
     -V, --version         print the version number and exit

You should specify a GitLab server hostname (``-g``), a GitLab registry
server hostname (``-r``) and either a credentials file (``-c``) or
username (``-u``) and password (read from stdin).

Final disk cleanup
~~~~~~~~~~~~~~~~~~

``gitlab-registry-cleanup`` only *soft* deletes images. As a result,
images are removed but their data (the image layers) are still stored on
disk. To delete unused image layers, you must run the Docker registry
garbage collector. If you have installed the GitLab omnibus package, you
can run the following commands:

.. code:: bash

   sudo gitlab-ctl registry-garbage-collect