Pythonで関数の引数をargparseに自動登録する ref: http://qiita.com/mountcedar/items/1b2e76f3bfd18dcc1975

extract_arguments.py

#!/usr/bin/env python

import argparse
from inspect import getargspec

def set_arguments(parser, func):
    args, varargs, keywords, defaults = getargspec(func)

    print 'args: ', args
    print 'varargs', varargs
    print 'keywords: ', keywords
    print 'defaults: ', defaults

    while len(args) > len(defaults):
        l = list(defaults)
        l.insert(0, None)
        defaults = tuple(l)

    for arg, default in zip(args, defaults):
        if default is None:
            parser.add_argument(dest=arg)
        elif type(default) is tuple or type(default) is list:
            parser.add_argument(
                '--' + arg,
                default=default,
                type=type(default),
                nargs='+'
            )
        elif type(default) is bool and default:
            parser.add_argument(
                '--disable_' + arg,
                dest=arg,
                default=default,
                action="store_false"
            )
        elif type(default) is bool and not default:
            parser.add_argument(
                '--enable_' + arg,
                dest=arg,
                default=default,
                action="store_true"
            )
        else:
            parser.add_argument(
                '--' + arg,
                default=default,
                type=type(default)
            )
    return parser

def func(x, aaa=1, bbb="a", ccc=[1,2,3,], ddd=True, eee=False):
    pass


parser = argparse.ArgumentParser()
parser = set_arguments(parser, func)
print parser.parse_args()

file0.txt

from inspect import getargspec

def func(aaa=1, bbb="a", ccc=[1,2,3,]):
    pass

args, varargs, keywords, defaults = getargspec(func)

print 'args: ', args
print 'varargs', varargs
print 'keywords: ', keywords
print 'defaults: ', defaults

file1.txt

args:  ['aaa', 'bbb', 'ccc']
varargs None
keywords:  None
defaults:  (1, 'a', [1, 2, 3])

file2.txt

from inspect import getargspec

def func(aaa=1, bbb="a", ccc=[1,2,3,]):
    pass

args, varargs, keywords, defaults = getargspec(func)

import argparse

parser = argparse.ArgumentParser()
for arg, default in zip(args, defaults):
    parser.add_argument(
        '--' + arg,
        default=default,
        type=type(default)
    )

print parser.parse_args()

file3.txt

Namespace(aaa=1, bbb='a', ccc=[1, 2, 3])

file4.txt

from inspect import getargspec

def func(aaa=1, bbb="a", ccc=[1,2,3,]):
    pass

args, varargs, keywords, defaults = getargspec(func)

import argparse

parser = argparse.ArgumentParser()
for arg, default in zip(args, defaults):
    if type(default) is tuple or type(default) is list:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default),
            nargs='+'
        )
    else:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default)
        )

file5.txt

from inspect import getargspec


def func(aaa=1, bbb="a", ccc=[1,2,3,], ddd=True, eee=False):
    pass

args, varargs, keywords, defaults = getargspec(func)

import argparse

parser = argparse.ArgumentParser()
for arg, default in zip(args, defaults):
    if type(default) is tuple or type(default) is list:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default),
            nargs='+'
        )
    elif type(default) is bool and default:
        parser.add_argument(
            '--disable_' + arg,
            dest=arg,
            default=default,
            action="store_false"
        )
    elif type(default) is bool and not default:
        parser.add_argument(
            '--enable_' + arg,
            dest=arg,
            default=default,
            action="store_true"
        )
    else:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default)
        )

file6.txt

from inspect import getargspec

def func(x, aaa=1, bbb="a", ccc=[1,2,3,], ddd=True, eee=False):
    pass

args, varargs, keywords, defaults = getargspec(func)

print 'args: ', args
print 'varargs', varargs
print 'keywords: ', keywords
print 'defaults: ', defaults

parser = argparse.ArgumentParser()

while len(args) > len(defaults):
    l = list(defaults)
    l.insert(0, None)
    defaults = tuple(l)

for arg, default in zip(args, defaults):
    if default is None:
        parser.add_argument(dest=arg)
    elif type(default) is tuple or type(default) is list:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default),
            nargs='+'
        )
    elif type(default) is bool and default:
        parser.add_argument(
            '--disable_' + arg,
            dest=arg,
            default=default,
            action="store_false"
        )
    elif type(default) is bool and not default:
        parser.add_argument(
            '--enable_' + arg,
            dest=arg,
            default=default,
            action="store_true"
        )
    else:
        parser.add_argument(
            '--' + arg,
            default=default,
            type=type(default)
        )

print parser.parse_args()

file9.txt

$ python ./register_argments.py a
Namespace(aaa=1, bbb='a', ccc=[1, 2, 3], ddd=True, eee=False, x='a')

register_arguments.py

#!/usr/bin/env python

import argparse
from inspect import getargspec

def register_arguments(parser, func):
    args, varargs, keywords, defaults = getargspec(func)
    while len(args) > len(defaults):
        l = list(defaults)
        l.insert(0, None)
        defaults = tuple(l)

    for arg, default in zip(args, defaults):
        if default is None:
            parser.add_argument(dest=arg)
        elif type(default) is tuple or type(default) is list:
            parser.add_argument(
                '--' + arg,
                default=default,
                type=type(default),
                nargs='+'
            )
        elif type(default) is bool and default:
            parser.add_argument(
                '--disable_' + arg,
                dest=arg,
                default=default,
                action="store_false"
            )
        elif type(default) is bool and not default:
            parser.add_argument(
                '--enable_' + arg,
                dest=arg,
                default=default,
                action="store_true"
            )
        else:
            parser.add_argument(
                '--' + arg,
                default=default,
                type=type(default)
            )
    return parser

def register_argparse(parser):
    def wrapper(f):
        register_arguments(parser, f)
        return f
    return wrapper

if __name__ == '__main__':
    parser = argparse.ArgumentParser()

    @register_argparse(parser)
    def func(x, aaa=1, bbb="a", ccc=[1,2,3,], ddd=True, eee=False):
        pass

    print parser.parse_args()