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-rw-r--r--Testcases/cfgm_common/importutils.py66
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diff --git a/Testcases/cfgm_common/importutils.py b/Testcases/cfgm_common/importutils.py
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+# 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('.')
+ __import__(mod_str)
+ try:
+ return getattr(sys.modules[mod_str], class_str)
+ except 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):
+ """Tries to import object from default namespace.
+
+ Imports 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