Coverage for keystone.openstack.common.importutils : 0%

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

# Copyright 2011 OpenStack Foundation. 

# 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. 

""" 

Import related utilities and helper functions. 

""" 

import sys 

import traceback 

def import_class(import_str): 

    """Returns a class from a string including module and class""" 

    mod_str, _sep, class_str = import_str.rpartition('.') 

    try: 

        __import__(mod_str) 

        return getattr(sys.modules[mod_str], class_str) 

    except (ValueError, AttributeError): 

        raise ImportError('Class %s cannot be found (%s)' % 

                          (class_str, 

                           traceback.format_exception(*sys.exc_info()))) 

def import_object(import_str, *args, **kwargs): 

    """Import a class and return an instance of it.""" 

    return import_class(import_str)(*args, **kwargs) 

def import_object_ns(name_space, import_str, *args, **kwargs): 

    """ 

    Import a class and return an instance of it, first by trying 

    to find the class in a default namespace, then failing back to 

    a full path if not found in the default namespace. 

    """ 

    import_value = "%s.%s" % (name_space, import_str) 

    try: 

        return import_class(import_value)(*args, **kwargs) 

    except ImportError: 

        return import_class(import_str)(*args, **kwargs) 

def import_module(import_str): 

    """Import a module.""" 

    __import__(import_str) 

    return sys.modules[import_str] 

def try_import(import_str, default=None): 

    """Try to import a module and if it fails return default.""" 

    try: 

        return import_module(import_str) 

    except ImportError: 

        return default