argparse_updates.py

from Queue import Empty, Queue
from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter, Namespace
from glob import glob

import os
from itertools import count
from threading import Thread
from time import sleep


def create_arg_parser():
    parser = ArgumentParser(description='options test',
                            formatter_class=ArgumentDefaultsHelpFormatter)
    parser.add_argument('-d',
                        '--delay',
                        type=float,
                        default=1.0)
    parser.add_argument('-m',
                        '--message',
                        default='Howdy')
    return parser


def create_files(queue):
    for filename in glob('copy_test/*'):
        os.remove(filename)
    args = delay = None
    file_count = 0
    while True:
        try:
            args = queue.get(timeout=delay)
            print('Created {} files.'.format(file_count))
            if args.quit:
                break
            delay = args.delay
        except Empty:
            # continue with current args
            filename = os.path.join(
                'copy_test',
                '{} {} for {:g}.txt'.format(args.message,
                                            file_count,
                                            args.delay))
            with open(filename, 'w') as f:
                f.write('x')
            file_count += 1


def main():
    queue = Queue()
    parser = create_arg_parser()
    args = Namespace(quit=False, **vars(parser.parse_args()))

    # noinspection PyProtectedMember
    commands = sorted((option.option_strings[0][-1], option.dest)
                      for option in parser._optionals._actions
                      if option.dest != 'help')
    attrs = dict(commands)
    commands.append(('s', 'status?'))
    commands.append(('q', 'quit!'))

    thread = Thread(target=create_files, args=(queue,))
    thread.start()

    try:
        while not args.quit:
            queue.put(args)
            sleep(0.1)
            for code, command in commands:
                message = '  ' + command + ' ' + code
                if code in attrs:
                    message += str(getattr(args, command))
                print(message)
            request = raw_input('Enter a code and an optional value: ')
            code = request[0].lower()
            value = request[1:].strip()
            if code == 'q':
                break
            elif code != 's':
                attr = attrs.get(code)
                if attr is None:
                    print('Unknown code.')
                else:
                    parser.parse_args(['-'+code, value], args)
    finally:
        args.quit = True
        queue.put(args)
    thread.join()


main()