Fetch all tags from a Docker image

docker-tags.py

#!/usr/bin/env python3

import requests
import sys

if __name__ == "__main__":
  if len(sys.argv) != 2:
    print("usage: python3 docker-tags.py IMAGE")
    exit(1)

  image = sys.argv[1]

  if "/" not in image:
    image = "library/" + image

  url = "https://registry.hub.docker.com/v2/repositories/%s/tags/" % image
  page = 1
  tags = []

  while url:
    print("[*] fetching page", page)

    response = requests.get(url)
    json = response.json()

    tags += [tag.get("name", "") for tag in json.get("results", [])]
    url = json.get("next", False)
    page += 1

  print("\n".join(sorted(tags)))