Python script for generating password on your local machine.

generate_password.py

"""Password generater
Generate random passwords on your local computer.

Usage: $ python filename.py [num]
    Option: num: Password characters number. Default 16. num > 3 (with special chars, > 4)

- Type of characters: Number, uppercase, lowercase. At least once.
    - Option: Set special_characters variable when using symbols or specific characters

Output: Genarated password is copied to clipboard (not shown in console)
"""
import random
import string
import sys


def hasNumbers(inputString):
    return any(char.isdigit() for char in inputString)


def hasUppercase(inputString):
    return any(char.isupper() for char in inputString)


def hasLowercase(inputString):
    return any(char.islower() for char in inputString)


def hasSymbols(inputString):
    if special_characters:
        return any(char in special_characters for char in inputString)
    else:
        return 1


def generate_password(char_num):
    if char_num < char_threshold:
        print(f"Error: Required char_num >= {char_threshold}")
        sys.exit()

    # assert all types are included
    while 1:
        x = "".join(
            random.choices(
                string.ascii_letters + string.digits + special_characters, k=char_num
            )
        )
        if hasNumbers(x) * hasUppercase(x) * hasLowercase(x) * hasSymbols(x):
            return x


def send_to_clipboard(text):
    try:
        from Tkinter import Tk
    except ImportError:
        from tkinter import Tk
    r = Tk()
    r.withdraw()
    r.clipboard_clear()
    r.clipboard_append(text)
    r.update()  # now it stays on the clipboard after the window is closed
    r.destroy()


def main():
    char_num = 16  # default

    try:
        assert char_num >= char_threshold
    except AssertionError:
        print(
            f"Error. Command is like `python filename.py num`. num >= {char_threshold}, instead of {char_num}"
        )
        sys.exit()

    # overwrite char_num if arg is set
    try:
        set_num = int(sys.argv[1])
        assert set_num >= char_threshold
        char_num = set_num
    except (IndexError):
        pass  # sys.argv[1] is not set.
    except (AssertionError, ValueError):
        print(
            f"Error. Command is like `python filename.py 16`. Number >= {char_threshold}"
        )
        sys.exit()

    my_password = generate_password(char_num)
    send_to_clipboard(my_password)
    print(f"Generated {char_num} char password was sent to clipboard!")


if __name__ == "__main__":
    special_characters = ""
    # special_characters = " !\"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"

    if special_characters:
        char_threshold = 4
    else:
        char_threshold = 3
    main()