unity-auto-deploy.py

#!/usr/bin/python

import subprocess
import os
import re
import sys
import time
import datetime

def log_info(msg):
  ts = datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d %H:%M:%S')
  print '%s [info ] %s' % (ts, msg)

def log_err(msg):
  ts = datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d %H:%M:%S')
  print >> sys.stderr, '%s [error] %s' % (ts, msg)

def run(cmd, cwd = None, stdout = subprocess.PIPE):
  p = subprocess.Popen(cmd, cwd = cwd, env = os.environ, stdout = stdout, stderr = subprocess.PIPE)
  stdout, err = p.communicate()
  if p.wait() != 0: raise Exception(err)
  return stdout

def run_docker(cmd, cwd = None, stdout = subprocess.PIPE):
  docker_bin = '/usr/bin/docker'
  return run([docker_bin] + cmd, cwd = cwd, stdout = stdout)

def docker_pull(name, tag):
  return run_docker(['pull', name + ':' + tag], stdout = None)

def docker_images():
  stdout = run_docker(['images', '--no-trunc=true'])

  res = {}
  for l in stdout.splitlines():
    m = re.search('''^([^\s]+)\s+([^\s]+)\s+([0-9a-f]{64})''', l)
    if m != None:
      name = m.group(1)
      tag = m.group(2)
      id = m.group(3)
      if name != '<none>' and tag != '<none>':
        res[name + ':' + tag] = id
  return res

def docker_image_id(name, tag):
  images = docker_images()
  key = name + ':' + tag

  if key in images:
    return images[key]
  else:
    return None

def docker_pull_and_check(name, tag):
  id_pre = docker_image_id(name, tag)
  log_info('Current %s:%s image is %s' % (name, tag, id_pre))

  docker_pull(name, tag)

  id_post = docker_image_id(name, tag)
  log_info('Updated %s:%s image is %s' % (name, tag, id_post))

  return id_pre != id_post

images = [
  { 'name': 'docker.epages.com/unity/epages-ui', 'tag': 'develop' },
  { 'name': 'docker.epages.com/unity/epages-ui-storage', 'tag': 'dev' },
  { 'name': 'docker.epages.com/unity/epages-imageservice', 'tag': 'dev' }
]

log_info('Updating images')
updates = map(lambda x: docker_pull_and_check(x['name'], x['tag']), images)

if any(updates):
  log_info('At least one image updated. Restarting instance')
  run(['/sbin/restart', 'unity-develop'])
else:
  log_info('Already running most recent images')

unity-deploy.conf

description "Unity development"
author "Christian Hoffmeister"

start on filesystem and started docker
stop on runlevel [!2345]

respawn

chdir /var/instances/unitydevelop

script
  /usr/local/bin/docker-compose up
end script

post-stop script
  /usr/local/bin/docker-compose kill
  /usr/local/bin/docker-compose rm -vf
end script