Deckschrubber

n. person responsible for scrubbing a ship's deck.

Deckschrubber inspects images of a Docker Registry and removes those older than a given age.

Quick Start

go get github.com/fraunhoferfokus/deckschrubber
$GOPATH/bin/deckschrubber

Why this?

We run our own private registry on a server with limited storage and it was only a question of time, until it was full! Although there are similar approaches to do Docker registry house keeping (in Python, Ruby, etc), a native module (using Docker's own packages) was missing. This module has the following advantages:

• Is binary!: No runtime, Python, Ruby, etc. is required
• Uses Docker API: same packages and modules used to relaze Docker registry are used here

Arguments

-day int
      max age in days
-debug
      run in debug mode      
-dry
      does not actually delete
-frequency
      repeat the task every X seconds
-insecure
      Skip TLS verification
-latest int
      number of the latest matching images of an repository that won't be deleted (default 1)      
-month int
      max age in months
-password string
      password for authentication
-registry string
      URL of registry (default "http://localhost:5000")
-repo string
      matching repositories (allows regexp) (default ".*")      
-repos int
      number of repositories to garbage collect (default 5)
-tag string
      matching tags (allows regexp) (default ".*")      
-user string
      username for authentication
-ntag string
      match everything but this tag (allows regexp) (default empty)
-v    shows version and quits
-year int
      max age in days
      
      

Registry preparation

Deckschrubber uses the Docker Registry API. Its delete endpoint is disabled by default, you have to enable it with the following entry in the registry configuration file:

delete:
  enabled: true

See the documentation for details.

Examples

• Remove all images older than 2 months and 2 days

$GOPATH/bin/deckschrubber -month 2 -day 2

• Remove all images older than 1 year from http://myrepo:5000

$GOPATH/bin/deckschrubber -year 1 -registry http://myrepo:5000

• Analyize (but do not remove) images of 30 repositories

$GOPATH/bin/deckschrubber -repos 30 -dry

• Remove all images of each repository except the 3 latest ones

$GOPATH/bin/deckschrubber -latest 3 

• Remove all images with tags that ends with '-SNAPSHOT'

$GOPATH/bin/deckschrubber -tag ^.*-SNAPSHOT$ 

Using docker image

Example docker-compose.yml:

version: "3"
services:
  deckschrubber:
    image: mobilejazz/deckschrubber:0.7.1
    environment:
     - REGISTRY=https://myregistry.example.com
     - USER=admin
     - PASSWORD=s00p3rs33cret
     - FREQUENCY=86400 # 1 day in seconds