Programming Forums > Script Programming > Python

Jessehk · Mar 2nd, 2006, 10:07 PM

I made a password-generator in Python.
I figure that it would be much faster if it could be called like this

Quote:

password <length> [options]

I was just wondering if I handled these arguments appropriately, and if I didn't, how the program could be improved.

#!/usr/bin/python

import random, sys

class Password:
	lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz']
	upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ']
	numbers = [str(x) for x in range(10)]
	symbols = [s for s in '\/<>!@#$%^&*']

	def __init__(self, length, lower, upper, symbol, number):
		if length < 0:
			raise ValueError("Invalid length of password.")
		
		else:
			possible = []
			if lower:
				possible.extend(self.lower_letters) #include lower-case letters
			if upper:
				possible.extend(self.upper_letters) #include upper-case letters
			if symbol:
				possible.extend(self.symbols) #include symbols
			if number:
				possible.extend(self.numbers) #include [0 - 9]

			self.password = []
			
			for x in range(length):
				self.password.append(random.choice(possible))
		
	def get_password(self):
		return "".join(self.password) #string version of password

def main():
	lower = upper = number = symbol = False

	error = """Invalid usage

	password <length> [options]

	options
	-------
	
	-l : include lower-case letters in the password
	-u : include upper-case letters in the password
	-s : include symbols in the password
	-n : include the digits 0 - 9 in the password
	-* : include everything in the password
	"""
	
	try:
		if len(sys.argv) < 2:
			raise ValueError(error)

		if "-*" in sys.argv:
			lower = upper = number = symbol = True
		
		else:
			if "-l" in sys.argv:
				lower = True
			if "-u" in sys.argv:
				upper = True
			if "-n" in sys.argv:
				number = True
			if "-s" in sys.argv:
				symbol = True
		
			
		if not True in (lower, upper, number, symbol):
			raise ValueError(error)

		p = Password(int(sys.argv[1]), lower, upper, symbol, number)
		print p.get_password()
	
	except ValueError, ve:
		print error

if __name__ == '__main__':
	main()

hydroxide · Mar 2nd, 2006, 10:21 PM

Use the optparse module - you'll end up with shorter, more robust, and more extensible code.

-T.

Sane · Mar 2nd, 2006, 10:41 PM

Just a note, I prefer doing stuff like:

(Toggle Plain Text)

	lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz']
	upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ']

In a shorter fasion such as:

(Toggle Plain Text)

        lower_letters = [chr(letter) for letter in range(97, 123)]
        upper_letters = [chr(letter) for letter in range(65, 91)]

Just a personal preference though.

Jessehk · Mar 2nd, 2006, 11:06 PM

New Version:

(Toggle Plain Text)

#!/usr/bin/python

import random, sys
from optparse import OptionParser

class Password:
	lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz']
	upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ']
	numbers = [str(x) for x in range(10)]
	symbols = [s for s in '\/<>!@#$%^&*']

	def __init__(self, length, lower, upper, symbol, number):
		if length < 0:
			raise ValueError("Invalid length of password.")
		
		else:
			possible = []
			if lower:
				possible.extend(self.lower_letters) #include lower-case letters
			if upper:
				possible.extend(self.upper_letters) #include upper-case letters
			if symbol:
				possible.extend(self.symbols) #include symbols
			if number:
				possible.extend(self.numbers) #include [0 - 9]

			self.password = []
			
			for x in range(length):
				self.password.append(random.choice(possible))
		
	def get_password(self):
		return "".join(self.password) #string version of password

def main():
	parser = OptionParser(usage = "usage: %prog [options] length")
	parser.add_option("-l", action = "store_true", default = True, dest = "lower", help = "include lower-case letters (default)")
	parser.add_option("-u", action = "store_true", default = False, dest = "upper", help = "include upper-case letters")
	parser.add_option("-n", action = "store_true", default = False, dest = "number", help = "include the digits from 0 to 9")
	parser.add_option("-s", action = "store_true", default = False, dest = "symbol", help = "include symbols (eg: $%^\/!)")

	(options, args) = parser.parse_args()
	if len(args) != 1:
		parser.error("Incorrect number of arguments")

	try:
		p = Password(int(args[0]), options.lower, options.upper, options.number, options.symbol)

	except ValueError, ve:
		parser.print_help()
	
	else:
		print p.get_password()

if __name__ == '__main__':
	main()

Thanks for info, OH!

@Sane: I appreciate the advice, but I think my method is a bit more readable (ie: the intention is clearly obvious).

Arevos · Mar 3rd, 2006, 2:49 AM

Quote:

Originally Posted by Sane

In a shorter fasion such as:

(Toggle Plain Text)

        lower_letters = [chr(letter) for letter in range(97, 123)]
        upper_letters = [chr(letter) for letter in range(65, 91)]

Just a personal preference though.

Or, use the string module:

(Toggle Plain Text)

lower_letters = list(string.ascii_lowercase)
upper_letters = list(string.ascii_uppercase)
numbers = list(string.digits)
symbols = list("\/<>!@#$%^&*")

Cerulean · Mar 3rd, 2006, 8:29 PM

Yeah, things like [x for x in "some string"] are redundant as list("some string") does the same. I would imagine the latter is faster too.
I don't know about using the string module really. You type less for digits without the module (i.e len("'0123456789'") < len("string.digits")), and just a little more for upper case and lower case characters. I only use it for string.punctuation

Jessehk · Mar 3rd, 2006, 11:30 PM

Somehow, list(string) was absent from my mind. I'll remember for the future I suppose.

Mar 2nd, 2006, 10:41 PM	#3
Sane Banned Join Date: Apr 2005 Location: Waterloo, Ontario Posts: 2,101 Rep Power: 6	Just a note, I prefer doing stuff like: (Toggle Plain Text) lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz'] upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ'] lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz'] upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ'] In a shorter fasion such as: (Toggle Plain Text) lower_letters = [chr(letter) for letter in range(97, 123)] upper_letters = [chr(letter) for letter in range(65, 91)] lower_letters = [chr(letter) for letter in range(97, 123)] upper_letters = [chr(letter) for letter in range(65, 91)] Just a personal preference though.

Mar 2nd, 2006, 11:06 PM	#4
Jessehk The Oblivious One Join Date: May 2005 Location: Ontario, Canada Posts: 648 Rep Power: 4	New Version: (Toggle Plain Text) #!/usr/bin/python import random, sys from optparse import OptionParser class Password: lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz'] upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ'] numbers = [str(x) for x in range(10)] symbols = [s for s in '\/<>!@#$%^&'] def __init__(self, length, lower, upper, symbol, number): if length < 0: raise ValueError("Invalid length of password.") else: possible = [] if lower: possible.extend(self.lower_letters) #include lower-case letters if upper: possible.extend(self.upper_letters) #include upper-case letters if symbol: possible.extend(self.symbols) #include symbols if number: possible.extend(self.numbers) #include [0 - 9] self.password = [] for x in range(length): self.password.append(random.choice(possible)) def get_password(self): return "".join(self.password) #string version of password def main(): parser = OptionParser(usage = "usage: %prog [options] length") parser.add_option("-l", action = "store_true", default = True, dest = "lower", help = "include lower-case letters (default)") parser.add_option("-u", action = "store_true", default = False, dest = "upper", help = "include upper-case letters") parser.add_option("-n", action = "store_true", default = False, dest = "number", help = "include the digits from 0 to 9") parser.add_option("-s", action = "store_true", default = False, dest = "symbol", help = "include symbols (eg: $%^\/!)") (options, args) = parser.parse_args() if len(args) != 1: parser.error("Incorrect number of arguments") try: p = Password(int(args[0]), options.lower, options.upper, options.number, options.symbol) except ValueError, ve: parser.print_help() else: print p.get_password() if __name__ == '__main__': main() #!/usr/bin/python import random, sys from optparse import OptionParser class Password: lower_letters = [letter for letter in 'abcdefghijklmnopqrstuvwxyz'] upper_letters = [letter for letter in 'ABCDEFGHIJKLMNOPQRSTUVWXWZ'] numbers = [str(x) for x in range(10)] symbols = [s for s in '\/<>!@#$%^&'] def __init__(self, length, lower, upper, symbol, number): if length < 0: raise ValueError("Invalid length of password.") else: possible = [] if lower: possible.extend(self.lower_letters) #include lower-case letters if upper: possible.extend(self.upper_letters) #include upper-case letters if symbol: possible.extend(self.symbols) #include symbols if number: possible.extend(self.numbers) #include [0 - 9] self.password = [] for x in range(length): self.password.append(random.choice(possible)) def get_password(self): return "".join(self.password) #string version of password def main(): parser = OptionParser(usage = "usage: %prog [options] length") parser.add_option("-l", action = "store_true", default = True, dest = "lower", help = "include lower-case letters (default)") parser.add_option("-u", action = "store_true", default = False, dest = "upper", help = "include upper-case letters") parser.add_option("-n", action = "store_true", default = False, dest = "number", help = "include the digits from 0 to 9") parser.add_option("-s", action = "store_true", default = False, dest = "symbol", help = "include symbols (eg: $%^\/!)") (options, args) = parser.parse_args() if len(args) != 1: parser.error("Incorrect number of arguments") try: p = Password(int(args[0]), options.lower, options.upper, options.number, options.symbol) except ValueError, ve: parser.print_help() else: print p.get_password() if __name__ == '__main__': main() Thanks for info, OH! @Sane: I appreciate the advice, but I think my method is a bit more readable (ie: the intention is clearly obvious). __________________ Dr. Zoidberg: [ecstatic] I'm going to a movie... with FRIENDS!

Mar 3rd, 2006, 11:30 PM	#7
Jessehk The Oblivious One Join Date: May 2005 Location: Ontario, Canada Posts: 648 Rep Power: 4	Somehow, list(string) was absent from my mind. I'll remember for the future I suppose. __________________ Dr. Zoidberg: [ecstatic] I'm going to a movie... with FRIENDS!

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Mar 2nd, 2006, 10:21 PM	#2
hydroxide Programmer Join Date: Apr 2005 Posts: 73 Rep Power: 4	Use the optparse module - you'll end up with shorter, more robust, and more extensible code. -T.

Mar 3rd, 2006, 8:29 PM	#6
Cerulean Professional Programmer Join Date: Apr 2005 Location: London, England Posts: 459 Rep Power: 4	Yeah, things like [x for x in "some string"] are redundant as list("some string") does the same. I would imagine the latter is faster too. I don't know about using the string module really. You type less for digits without the module (i.e len("'0123456789'") < len("string.digits")), and just a little more for upper case and lower case characters. I only use it for string.punctuation

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Programming Forums > Script Programming > Python

Defining and handling command-line options