ironic-python-agent/ironic_python_agent/tests/unit/base.py
John L. Villalovos fc3de87469 Fix issue with double mocking of utils.execute functions
An issue was discovered if we mock an already mock-ed function. This
was happening in our execute() detection code. Change it to not use a
mock and instead a function.

Add unit tests to show it works as intended.

Change-Id: Ia116b355e7adb3cbfb8ae34f4d59bf527f2889bb
2017-12-01 07:42:02 -08:00

80 lines
2.8 KiB
Python

# Copyright 2017 Cisco Systems, Inc
#
# 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 and classes across all unit tests."""
import subprocess
import ironic_lib
from oslo_concurrency import processutils
from oslo_config import cfg
from oslo_config import fixture as config_fixture
from oslotest import base as test_base
from ironic_python_agent import utils
CONF = cfg.CONF
class IronicAgentTest(test_base.BaseTestCase):
"""Extends the base test to provide common features across agent tests."""
# By default block execution of utils.execute() and related functions.
block_execute = True
def setUp(self):
super(IronicAgentTest, self).setUp()
self._set_config()
# Ban running external processes via 'execute' like functions. If the
# patched function is called, an exception is raised to warn the
# tester.
if self.block_execute:
# NOTE(jlvillal): pyudev.Context() calls ctypes.find_library()
# which calls subprocess.Popen(). So not blocking
# subprocess.Popen()
# NOTE(jlvillal): Intentionally not using mock as if you mock a
# mock it causes things to not work correctly. As doing an
# autospec=True causes strangeness. By using a simple function we
# can then mock it without issue.
self.patch(ironic_lib.utils, 'execute', do_not_call)
self.patch(processutils, 'execute', do_not_call)
self.patch(subprocess, 'call', do_not_call)
self.patch(subprocess, 'check_call', do_not_call)
self.patch(subprocess, 'check_output', do_not_call)
self.patch(utils, 'execute', do_not_call)
def _set_config(self):
self.cfg_fixture = self.useFixture(config_fixture.Config(CONF))
def config(self, **kw):
"""Override config options for a test."""
self.cfg_fixture.config(**kw)
def set_defaults(self, **kw):
"""Set default values of config options."""
group = kw.pop('group', None)
for o, v in kw.items():
self.cfg_fixture.set_default(o, v, group=group)
def do_not_call(*args, **kwargs):
"""Helper function to raise an exception if it is called"""
raise Exception(
"Don't call ironic_lib.utils.execute() / "
"processutils.execute() or similar functions in tests!")