Convert AWS credentials into an easier format ot script with.

list-aws-creds.py

#!/usr/bin/env python3
from __future__ import annotations

import argparse
import configparser as ConfigParser
import json
import re

from enum import Enum
from pathlib import Path

AWS_CREDS_FILE = Path("~/.aws/credentials").expanduser()


class OutputMode(Enum):
    JSON = "json"
    TABLE = "table"


def parse_credentials(
    filepath: Path,
) -> dict[str, int]:
    """
    Parse AWS credentials file and return a dictionary of account names and ids.

    Args:
        filepath (Path): path to AWS credentials file (default: ~/.aws/credentials)

    Returns:
        dict[str, int]: dictionary of account names and ids
    """
    config = ConfigParser.ConfigParser()
    config.read(filepath.absolute())

    accounts: dict[str, int] = {}
    for section in config.sections():
        # only sections with "credential_process" contain aws account ids
        if not config.has_option(section, "credential_process"):
            continue

        credential_process = config.get(section, "credential_process")
        account_id_matches = re.findall(r"(\d+)", credential_process)
        if not account_id_matches:
            continue

        account_id = int(account_id_matches[0])
        accounts.setdefault(section, account_id)

    return accounts


def render(
    credentials: dict[str, int],
    output_mode: OutputMode,
) -> None:
    if not credentials:
        print("No AWS credentials found.")
        return

    match output_mode:
        case "json":
            print(
                json.dumps(
                    credentials,
                    indent=2,
                    sort_keys=True,
                )
            )

        case "table":
            max_account_len = 0
            max_account_id_len = 0
            for account, account_id in credentials.items():
                max_account_len = max(max_account_len, len(account))
                max_account_id_len = max(max_account_id_len, len(str(account_id)))

            credentials = dict(sorted(credentials.items(), key=lambda item: item[0]))
            credentials = {"account_id": "account"} | credentials

            for account, account_id in credentials.items():
                print(
                    f"{account_id: >{max_account_id_len}} {account: <{max_account_len}}"
                )


if __name__ == "__main__":
    argparser = argparse.ArgumentParser(
        prog="list-aws-creds",
        description="List AWS account names and ids from credentials file.",
        formatter_class=lambda prog: argparse.HelpFormatter(prog, max_help_position=30),
    )
    argparser.add_argument(
        "--file",
        type=Path,
        nargs="?",
        const=1,
        default=AWS_CREDS_FILE,
        help=f"path to AWS credentials file (default: {AWS_CREDS_FILE})",
    )
    argparser.add_argument(
        "--output",
        choices=[e.value for e in OutputMode],
        help="output format (default: table)",
        default=OutputMode.TABLE.value,
    )
    args = argparser.parse_args()

    credentials = parse_credentials(
        args.file,
    )
    render(credentials, output_mode=args.output)