core-admin/qubes/tools/__init__.py

#!/usr/bin/python2 -O
# vim: fileencoding=utf-8

#
# The Qubes OS Project, https://www.qubes-os.org/
#
# Copyright (C) 2015  Joanna Rutkowska <joanna@invisiblethingslab.com>
# Copyright (C) 2015  Wojtek Porczyk <woju@invisiblethingslab.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

'''Qubes' command line tools
'''

import argparse
import importlib


# TODO --verbose, logger setup
def get_parser_base(*args, **kwargs):
    '''Get base parser with options common to all Qubes OS tools.

    Currently supported options: ``--xml``.

    *args* and *kwargs* are passed to :py:class:`argparser.ArgumentParser`.
    '''
    parser = argparse.ArgumentParser(*args, **kwargs)

    parser.add_argument('--xml', metavar='XMLFILE',
        action='store',
        help='Qubes OS store file')

    return parser


def get_parser_for_command(command):
    '''Get parser for given qvm-tool.

    :param str command: command name
    :rtype: argparse.ArgumentParser
    :raises ImportError: when command's module is not found
    :raises AttributeError: when parser was not found
    '''

    module = importlib.import_module(
        '.' + command.replace('-', '_'), 'qubes.tools')

    try:
        parser = module.parser
    except AttributeError:
        try:
            parser = module.get_parser()
        except AttributeError:
            raise AttributeError('cannot find parser in module')

    return parser