Source code for heat.openstack.common.utils

# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2011 OpenStack LLC.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

"""
System-level utilities and helper functions.
"""

import logging

LOG = logging.getLogger(__name__)


def int_from_bool_as_string(subject):
    """
    Interpret a string as a boolean and return either 1 or 0.

    Any string value in:

        ('True', 'true', 'On', 'on', '1')

    is interpreted as a boolean True.

    Useful for JSON-decoded stuff and config file parsing
    """
    return bool_from_string(subject) and 1 or 0


def bool_from_string(subject):
    """
    Interpret a string as a boolean.

    Any string value in:

        ('True', 'true', 'On', 'on', 'Yes', 'yes', '1')

    is interpreted as a boolean True.

    Useful for JSON-decoded stuff and config file parsing
    """
    if isinstance(subject, bool):
        return subject
    if isinstance(subject, basestring):
        if subject.strip().lower() in ('true', 'on', 'yes', '1'):
            return True
    return False