get_latest_tag.py

# -*- coding: utf-8 -*-
# arkadiko
# https://github.com/topfreegames/arkadiko
# Licensed under the MIT license:
# http://www.opensource.org/licenses/mit-license
# Copyright © 2016 Top Free Games <backend@tfgco.com>

import urllib
import urllib2
import json

def main():
  url = "https://auth.docker.io/token?service=registry.docker.io&scope=repository:tfgco/arkadiko:pull,push"
  response = urllib.urlopen(url)
  token = json.loads(response.read())['token']

  url = "https://registry-1.docker.io/v2/tfgco/arkadiko/tags/list"
  req = urllib2.Request(url, None, {
    "Authorization": "Bearer %s" % token,
  })
  response = urllib2.urlopen(req)
  tags = json.loads(response.read())
  last_tag = get_last_tag(tags['tags'])
  print last_tag


def get_tag_value(tag):
  while len(tag) < 4:
    tag.append('0')

  total_value = 0
  for index, tag_part in enumerate(tag):
    power = pow(100, len(tag) - index)
    total_value += int(tag_part) * power

  return total_value


def get_last_tag(tags):
  return '.'.join(
    max([
      (get_tag_value(tag), tag) for tag in
      [t.split('.') for t in tags]
    ], key=lambda i: i[0]
    )[1]
  )


if __name__ == "__main__":
  main()