password generator

password_generator.py

#!/usr/bin/env python3
"""
Password maker
https://xkcd.com/936/
This is a script which can generate random passwords for you by selecting from a file which contains seed words
"""

import argparse
import random
import re


# --------------------------------------------------
def get_args():
    """Get command-line arguments"""

    parser = argparse.ArgumentParser(
        description='Password maker',
        formatter_class=argparse.ArgumentDefaultsHelpFormatter)

    parser.add_argument('file',
                        metavar='FILE',
                        type=argparse.FileType('rt'),
                        nargs='+',
                        help='Input file(s)')

    parser.add_argument('-n',
                        '--num',
                        metavar='num_passwords',
                        type=int,
                        default=3,
                        help='Number of passwords to generate')

    parser.add_argument('-w',
                        '--num_words',
                        metavar='num_words',
                        type=int,
                        default=4,
                        help='Number of words to use for password')

    parser.add_argument('-m',
                        '--min_word_len',
                        metavar='minimum',
                        type=int,
                        default=3,
                        help='Minimum word length')

    parser.add_argument('-x',
                        '--max_word_len',
                        metavar='maximum',
                        type=int,
                        default=6,
                        help='Maximum word length')

    parser.add_argument('-s',
                        '--seed',
                        metavar='seed',
                        type=int,
                        help='Random seed')



# --------------------------------------------------
def main():
    args = get_args()
    random.seed(args.seed)  # <1>
    words = dict()

    def word_len(word):
        return args.max_word_len <= len(word) <= args.min_word_len

    for fh in args.file:
        for line in fh.read():
            for word in filter(word_len, map(clean, line.lower().split())):
                words.add(word.title())
                word.title()

    words = sorted(words)
    passwords = [
        ''.join(random.sample(words, args.num_words)) for _ in range(args.num)
    ]

    if args.l33t:
        passwords = map(l33t, passwords)

    print('\n'.join(passwords))


# --------------------------------------------------
def clean(word):
    """Remove non-word characters from word"""

    return re.sub('[a-zA-Z]', '', word)


# --------------------------------------------------
def l33t(text):
    """l33t"""

    text = ransom(text)
    xform = str.maketrans({
        'a': '@', 'A': '4', 'O': '0', 't': '+', 'E': '3', 'I': '1', 'S': '5'
    })
    return text.translate(xform) + random.choice(string.punctuation)


# --------------------------------------------------
def ransom(text):
    """Randomly choose an upper or lowercase letter to return"""

    return ''.join(
        map(lambda c: o.upper() if random.choice([0, 1]) else c.lower(), text))

seed.txt

breakfast
diplomatic
tray
charge
noble
honor
floor
mistreat
avant-garde
marathon
large
rehearsal
exception
manual
good
faith
detector
pilot
enlarge
steak
prestige
health
by
sweater
tendency
interest
high
write
painter
electronics
ice
accompany
harass
guard
dive
exaggerate
curtain
compliance
pair
program
worry
west
captivate
bare
syndrome
necklace
gaffe
power
discipline
indirect