docker-volume-cleanup.py

#!/usr/bin/python

import json
import os
import shutil
import subprocess
import re

dockerdir = '/var/lib/docker'
volumesdir = os.path.join(dockerdir, 'volumes')

containers = dict((line, 1) for line in subprocess.check_output('docker ps -a -q --no-trunc', shell=True).splitlines())

volumes = os.walk(os.path.join(volumesdir, '.')).next()[1]
for volume in volumes:
    if not re.match('[0-9a-f]{64}', volume):
        print volume + ' is not a valid volume identifier, skipping...'
        continue
    volume_metadata = json.load(open(os.path.join(volumesdir, volume, 'config.json')))
    container_id = volume_metadata['ID']
    if container_id in containers:
        print 'Container ' + container_id[:12] + ' does still exist, not clearing up volume ' + volume
        continue
    print 'Deleting volume ' + volume + ' (container: ' + container_id[:12] + ')'
    volumepath = os.path.join(volumesdir, volume)
    print 'Volumepath: ' + volumepath
    shutil.rmtree(volumepath)