A random password generator

password_generator.py

import math
import random
import string
import argparse


def generate_password(nb_of_char, min_special=0):
    password = ''
    for i in range(nb_of_char, 0, -1):
        if min_special >= i:
            choices = string.punctuation
            min_special -= 1
        else:
            choices = string.ascii_letters + string.digits + string.punctuation
        password += random.choice(choices)
    return password


def check_password_strength(password):
    available_dictionaries = [string.digits, string.ascii_lowercase, string.ascii_uppercase, string.punctuation]
    dictionary_size = 0
    for char in password:
        for dictionary in available_dictionaries:
            if char in dictionary:
                dictionary_size += len(dictionary)
                available_dictionaries.remove(dictionary)
    return round(math.log2(dictionary_size ** len(password)), 2)


def main():
    parser = argparse.ArgumentParser(description="Generate random passwords")
    parser.add_argument("--password-count", '-n', type=int,
                        help="number of passwords to generate", default=1)
    parser.add_argument("--length", "-l", type=int,
                        help="Length of the passwords",
                        default=random.randint(4,30))
    parser.add_argument("--special-chars", "-s", type=int,
                        help="Minimum number of special characters",
                        default=random.randint(0,30))
    parser.add_argument("--show-strength", '-S', action='store_true',
                        help="display the strength of each generated password")
    args = parser.parse_args()

    for _ in range(args.password_count):
        password = generate_password(args.length, args.special_chars)
        output = password
        if args.show_strength:
            output = f"{password} {check_password_strength(password)}"
        print(output)


if __name__ == "__main__":
    main()