Revised multi-layered Argparse

stack10448200.py

import sys
import argparse


# noinspection PyShadowingNames
def parse_args(parser, commands):
    # Divide argv by commands
    split_argv = []
    for c in sys.argv[1:]:
        # noinspection PyProtectedMember
        if c in commands.choices or c in parser._option_string_actions.keys():
            if c == '-h' and len(split_argv) >= 1:
                split_argv[-1].append(c)
            else:
                split_argv.append([c])
        else:
            raise Exception('Argument "{0}" unknown.'.format(c))
    # Initialize namespace
    args = argparse.Namespace()
    for c in commands.choices:
        setattr(args, c, None)
    # Parse each command
    if len(split_argv) == 0:
        split_argv.append(['-h'])  # if no command was given
    parser.parse_args(split_argv[0], namespace=args)  # Without command
    for argv in split_argv[1:]:  # Commands
        n = argparse.Namespace()
        setattr(args, argv[0], n)
        parser.parse_args(argv, namespace=n)
    return args


parser = argparse.ArgumentParser()
commands = parser.add_subparsers(title='sub-commands')

cmd1_parser = commands.add_parser('cmd1')
cmd1_parser.add_argument('--foo')

cmd2_parser = commands.add_parser('cmd2')
cmd2_parser.add_argument('--foo')

cmd2_parser = commands.add_parser('cmd3')
cmd2_parser.add_argument('--foo')


args = parse_args(parser, commands)
print(args)