Password generator

pwgen.py

#!/usr/bin/env python3

import argparse
import secrets
import string


def generate_diceware_password(length, word_file):
    with open(word_file) as file:
        lines = [line.rstrip() for line in file]
    # TODO: Consider using only words longer than 3 chars.
    return ' '.join(secrets.choice(lines) for i in range(length))


def generate_standard_password(length):
    alphabet = string.ascii_letters + string.digits
    return ''.join(secrets.choice(alphabet) for i in range(length))


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "--length",
        type=int,
        required=True,
        help="Pasword length (in words or characters)")
    parser.add_argument(
        "--diceware",
        action="store_true",
        help=
        "Generate a diceware-style password rather than a string of random characters. Words will be randomly chosen from --word-file."
    )
    parser.add_argument(
        "--word-file",
        default="/usr/share/dict/words",
        help=
        "File to draw words from for diceword passwords. Each line should contain a single word."
    )
    args = parser.parse_args()

    if args.diceware:
        password = generate_diceware_password(args.length, args.word_file)
    else:
        password = generate_standard_password(args.length)
    print(password)


if __name__ == "__main__":
    main()