System Initiative

#!/usr/bin/env python3 """ Executes a `docker container run`. """ import json import os import re import sys from typing import List, Tuple def parse_args() -> Tuple[str, List[str], List[str]]: this_prog = sys.argv.pop(0) if sys.argv.pop(0) != "--tags-file": print( f"xxx usage: {this_prog} --tags-file TAGS_FILE ARGV...", file=sys.stderr, ) tags_file = sys.argv.pop(0) docker_args = [] while True: arg = sys.argv.pop(0) if arg == "--": break else: docker_args.append(arg) return (tags_file, docker_args, sys.argv) def main() -> int: tags_file, docker_args, args = parse_args() tags = load_tags(tags_file) cmd = [ "docker", "container", "run", "--rm", "--tty", "--interactive", ] for arg in docker_args: cmd.append(resolve_env_vars(arg)) cmd.append(tags[0]) cmd.extend(args) print("--- Running container: {}".format(" ".join(cmd))) os.execvp(cmd[0], cmd) def load_tags(tags_file: str) -> List[str]: with open(tags_file) as file: tags = json.load(file) return tags def resolve_env_vars(arg: str) -> str: wrapped_var_re = re.compile(r"\${([a-zA-Z_]\w*)}") raw_var_re = re.compile(r"\$([a-zA-Z_]\w*)") return raw_var_re.sub( resolve_env_var, wrapped_var_re.sub(resolve_env_var, arg), ) def resolve_env_var(match: re.Match) -> str: env_var = match.group(1) if env_var and os.getenv(env_var): return os.getenv(env_var, "") else: return "" if __name__ == "__main__": sys.exit(main())