import sys, argparse
# option decorator
def option(*args, **kwds):
def _decorator(func):
_option = (args, kwds)
if hasattr(func, 'options'):
func.options.append(_option)
else:
func.options = [_option]
return func
return _decorator
# arg decorator
arg = option
# combines option decorators
def option_group(*options):
def _decorator(func):
for option in options:
func = option(func)
return func
return _decorator
class MetaCommander(type):
def __new__(cls, classname, bases, classdict):
subcmds = {}
for name, func in classdict.items():
if name.startswith('do_'):
name = name[3:]
subcmd = {
'name': name,
'func': func,
'options': []
}
if hasattr(func, 'options'):
subcmd['options'] = func.options
subcmds[name] = subcmd
classdict['_argparse_subcmds'] = subcmds
return type.__new__(cls, classname, bases, classdict)
class Commander(object):
__metaclass__ = MetaCommander
name = 'app'
description = 'a description'
version = '0.0'
epilog = ''
default_args = []
def cmdline(self):
parser = argparse.ArgumentParser(
# prog = self.name,
formatter_class = argparse.RawDescriptionHelpFormatter,
description=self.__doc__,
epilog = self.epilog,
)
parser.add_argument('-v', '--version', action='version',
version = '%(prog)s '+ self.version)
subparsers = parser.add_subparsers(
title='subcommands',
description='valid subcommands',
help='additional help',
)
for name in sorted(self._argparse_subcmds.keys()):
subcmd = self._argparse_subcmds[name]
subparser = subparsers.add_parser(subcmd['name'],
help=subcmd['func'].__doc__)
for args, kwds in subcmd['options']:
subparser.add_argument(*args, **kwds)
subparser.set_defaults(func=subcmd['func'])
if len(sys.argv) <= 1:
options = parser.parse_args(self.default_args)
else:
options = parser.parse_args()
options.func(self, options)
def test():
# only for options which are repeated across different funcs
common_options = option_group(
option('-t', '--type', action='store', help='specify type of package'),
arg('package', help='package to be (un)installed'),
option('--log', '-l', action='store_true', help='log is on')
)
class Application(Commander):
'a description of the test app'
name = 'app1'
version = '0.1'
default_args = ['install', '--help']
@option('--log', '-l', action='store_true', help='log is on')
@arg('pattern', help="pattern to delete")
def do_delete(self, options):
"help text for delete subcmd"
print options
@option('-f', '--force', action='store_true',
help='force through installation')
@common_options
def do_install(self, options):
"help text for install subcmd"
print options
@common_options
def do_uninstall(self, options):
"help text for uninstall subcmd"
print options
app = Application()
app.cmdline()
if __name__ == '__main__':
test()
