Python 'argparse' Cookbook

argparse-cookbook.txt

### argparse Examples

Snippet for short and long version flags:

parser.add_argument('-b', '--block',
                    nargs="?",
                    action='store',
                    dest='block',
                    metavar='block',
                    help='stores a value in block for -b or --block')

Snippet for on/off flags like verbose, silent, etc:

parser.add_argument('-q', '--silent',
                    action='store_true',
                    default=False,
                    help='supress all output')

Snippet for flag without arguments:

parser.add_argument('-f', '--flag',
                    action='store_true',
                    help='[flag is set or not]')

Snippet for: program.py [flag [argument]]

parser.add_argument('flag',
                    nargs=argparse.REMAINDER,
                    metavar='[flag [argument]]',
                    help='flag with optional argument')
   args = parser.parse_args()
[...]
    if len(args.flag) > 1:
        argument = args.flag[1]

Snippet for flag with a single optional argument, set to default value if omitted:

parser.add_argument('-s', '--show',
                    nargs='?',
                    const=DEFAULT,
                    action='store',
                    metavar='argument',
                    dest='show',
                    type=str,
                    help='show has default or argument to flag')

mkaz.blog: https://mkaz.blog/code/python-argparse-cookbook/
Ariel Balter: https://gist.github.com/abalter/605773b34a68bb370bf84007ee55a130
Martin Thoma: https://martin-thoma.com/how-to-parse-command-line-arguments-in-python/

### Tools

Click: http://click.pocoo.org/
Docopt: https://github.com/docopt/docopt