# Copyright (c) 2013 Hewlett-Packard Development Company, L.P. # 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. """Common utilities used in testing""" import logging from unittest import mock import fixtures from oslotest import createfile from oslotest import log from oslotest import output from oslotest import timeout import testtools LOG = logging.getLogger(__name__) _TRUE_VALUES = ('True', 'true', '1', 'yes') _LOG_FORMAT = "%(levelname)8s [%(name)s] %(message)s" class BaseTestCase(testtools.TestCase): """Base class for unit test classes. If the environment variable ``OS_TEST_TIMEOUT`` is set to an integer value (**seconds**), a timer is configured to control how long individual test cases can run. This lets tests fail for taking too long, and prevents deadlocks from completely hanging test runs. The class variable ``DEFAULT_TIMEOUT`` can be set to configure a test suite default test value for cases in which ``OS_TEST_TIMEOUT`` is not set. It defaults to ``0``, which means no timeout. The class variable ``TIMEOUT_SCALING_FACTOR`` can be set on an individual test class for tests that reasonably take longer than the rest of the test suite so that the overall timeout can be kept small. It defaults to ``1``. If the environment variable ``OS_STDOUT_CAPTURE`` is set, a fake stream replaces ``sys.stdout`` so the test can look at the output it produces. If the environment variable ``OS_STDERR_CAPTURE`` is set, a fake stream replaces ``sys.stderr`` so the test can look at the output it produces. If the environment variable ``OS_DEBUG`` is set to a true value, debug logging is enabled. Alternatively, the ``OS_DEBUG`` environment variable can be set to a valid log level. If the environment variable ``OS_LOG_CAPTURE`` is set to a true value, a logging fixture is installed to capture the log output. Uses the fixtures_ module to configure a :class:`NestedTempFile` to ensure that all temporary files are created in an isolated location. Uses the fixtures_ module to configure a :class:`TempHomeDir` to change the ``HOME`` environment variable to point to a temporary location. PLEASE NOTE: Usage of this class may change the log level globally by setting the environment variable ``OS_DEBUG``. A mock of ``time.time`` will be called many more times than might be expected because it's called often by the logging module. A usage of such a mock should be avoided when a test needs to verify logging behavior or counts the number of invocations. A workaround is to overload the ``_fake_logs`` function in a base class but this will deactivate fake logging globally. .. _fixtures: https://pypi.org/project/fixtures """ DEFAULT_TIMEOUT = 0 TIMEOUT_SCALING_FACTOR = 1 def __init__(self, *args, **kwds): super(BaseTestCase, self).__init__(*args, **kwds) # This is the number of characters shown when two objects do not # match for assertDictEqual, assertMultiLineEqual, and # assertSequenceEqual. The default is 640 which is too # low for comparing most dicts self.maxDiff = 10000 def addCleanup(self, function, *args, **kwargs): # NOTE(dims): This is a hack for Mitaka. We'll need to undo this as # early as possible in Newton and advertise that this hack will not # be supported anymore. if (hasattr(self, '_cleanups') and isinstance(self._cleanups, list)): if not self._cleanups: # Ensure that the mock.patch.stopall cleanup is registered # before any addCleanup() methods have a chance to register # other things to be cleaned up, so it is called last. This # allows tests to register their own cleanups with a mock.stop # method so those mocks are not included in the stopall set. super(BaseTestCase, self).addCleanup(mock.patch.stopall) else: LOG.error('Unable to patch test case. ' 'mock.patch.stopall cleanup was not registered.') super(BaseTestCase, self).addCleanup(function, *args, **kwargs) def setUp(self): super(BaseTestCase, self).setUp() self._set_timeout() self._fake_output() self._fake_logs() self.useFixture(fixtures.NestedTempfile()) self.useFixture(fixtures.TempHomeDir()) def _set_timeout(self): self.useFixture(timeout.Timeout( default_timeout=self.DEFAULT_TIMEOUT, scaling_factor=self.TIMEOUT_SCALING_FACTOR, )) def _fake_output(self): self.output_fixture = self.useFixture(output.CaptureOutput()) def _fake_logs(self): self.log_fixture = self.useFixture(log.ConfigureLogging()) def create_tempfiles(self, files, ext='.conf', default_encoding='utf-8'): """Safely create temporary files. :param files: Sequence of tuples containing (filename, file_contents). :type files: list of tuple :param ext: File name extension for the temporary file. :type ext: str :param default_encoding: Default file content encoding when it is not provided, used to decode the tempfile contents from a text string into a binary string. :type default_encoding: str :return: A list of str with the names of the files created. """ tempfiles = [] for f in files: if len(f) == 3: basename, contents, encoding = f else: basename, contents = f encoding = default_encoding fix = self.useFixture(createfile.CreateFileWithContent( filename=basename, contents=contents, ext=ext, encoding=encoding, )) tempfiles.append(fix.path) return tempfiles