jordanjambazov / gitlab-registry-cleanup

A tool to clean up untagged GitLab registry images.

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.

Installation

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

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

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] [-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
  -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:

sudo gitlab-ctl registry-garbage-collect