nova/nova/tests/unit/test_test.py
Adam Spiers ca8f4be2a8 Move selective patching of open() to nova.test for reuse
Several existing tests patch open() to fake the contents of a file
outside the test virtualenv, whilst avoiding interfering with reading
and writing of other files inside the test virtualenv.  Currently they
do it by duplicating logic.

Furthermore, in the near future, more tests (specifically, some SEV
tests) will want to do the same selective patching, and similarly will
need to avoid impacting reads of other files within the test
virtualenv, e.g. placement-policy.yaml.

So create new patch_open() context manager / decorator in nova.test
for selectively patching open based on the path parameter, and reuse
this for existing tests.

Also add unit tests for all these cases.

mock >= 3.0.0 is required because configparser.RawConfigParser._read()
uses enumerate() to iterate over the lines of the (mocked)
/etc/nova/release config file, and this uses __iter__() under the hood
which was not supported via mock_open until a bug was fixed and
backported to the external mock library for 3.0.0:

    https://bugs.python.org/issue21258
    https://bugs.python.org/issue32933
    73f6eed0d6

Change-Id: I19f49c923d2c41eab0c7b4cab28c50498dc07046
2019-05-25 02:49:40 +00:00

434 lines
15 KiB
Python

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# 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.
"""Tests for the testing base code."""
import os.path
import tempfile
import uuid
import mock
from oslo_log import log as logging
import oslo_messaging as messaging
import six
import nova.conf
from nova import exception
from nova import rpc
from nova import test
from nova.tests import fixtures
LOG = logging.getLogger(__name__)
CONF = nova.conf.CONF
class IsolationTestCase(test.TestCase):
"""Ensure that things are cleaned up after failed tests.
These tests don't really do much here, but if isolation fails a bunch
of other tests should fail.
"""
def test_service_isolation(self):
self.useFixture(fixtures.ServiceFixture('compute'))
def test_rpc_consumer_isolation(self):
class NeverCalled(object):
def __getattribute__(self, name):
if name == 'target':
# oslo.messaging 5.31.0 explicitly looks for 'target'
# on the endpoint and checks it's type, so we can't avoid
# it here, just ignore it if that's the case.
return
assert False, "I should never get called. name: %s" % name
server = rpc.get_server(messaging.Target(topic='compute',
server=CONF.host),
endpoints=[NeverCalled()])
server.start()
class JsonTestCase(test.NoDBTestCase):
def test_compare_dict_string(self):
expected = {
"employees": [
{"firstName": "Anna", "lastName": "Smith"},
{"firstName": "John", "lastName": "Doe"},
{"firstName": "Peter", "lastName": "Jones"}
],
"locations": set(['Boston', 'Mumbai', 'Beijing', 'Perth'])
}
actual = """{
"employees": [
{
"lastName": "Doe",
"firstName": "John"
},
{
"lastName": "Smith",
"firstName": "Anna"
},
{
"lastName": "Jones",
"firstName": "Peter"
}
],
"locations": [
"Perth",
"Boston",
"Mumbai",
"Beijing"
]
}"""
self.assertJsonEqual(expected, actual)
def test_fail_on_list_length(self):
expected = {
'top': {
'l1': {
'l2': ['a', 'b', 'c']
}
}
}
actual = {
'top': {
'l1': {
'l2': ['c', 'a', 'b', 'd']
}
}
}
try:
self.assertJsonEqual(expected, actual)
except Exception as e:
# error reported is going to be a cryptic length failure
# on the level2 structure.
self.assertEqual(
("3 != 4: path: root.top.l1.l2. Different list items\n"
"expected=['a', 'b', 'c']\n"
"observed=['a', 'b', 'c', 'd']\n"
"difference=['d']"),
e.difference)
self.assertIn(
"actual:\n{'top': {'l1': {'l2': ['c', 'a', 'b', 'd']}}}",
six.text_type(e))
self.assertIn(
"expected:\n{'top': {'l1': {'l2': ['a', 'b', 'c']}}}",
six.text_type(e))
else:
self.fail("This should have raised a mismatch exception")
def test_fail_on_dict_length(self):
expected = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2, 'c': 3}
}
}
}
actual = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2}
}
}
}
try:
self.assertJsonEqual(expected, actual)
except Exception as e:
self.assertEqual(
("3 != 2: path: root.top.l1.l2. Different dict key sets\n"
"expected=['a', 'b', 'c']\n"
"observed=['a', 'b']\n"
"difference=['c']"),
e.difference)
else:
self.fail("This should have raised a mismatch exception")
def test_fail_on_dict_keys(self):
expected = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2, 'c': 3}
}
}
}
actual = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2, 'd': 3}
}
}
}
try:
self.assertJsonEqual(expected, actual)
except Exception as e:
self.assertIn(
"path: root.top.l1.l2. Dict keys are not equal",
e.difference)
else:
self.fail("This should have raised a mismatch exception")
def test_fail_on_list_value(self):
expected = {
'top': {
'l1': {
'l2': ['a', 'b', 'c']
}
}
}
actual = {
'top': {
'l1': {
'l2': ['c', 'a', 'd']
}
}
}
try:
self.assertJsonEqual(expected, actual)
except Exception as e:
self.assertEqual(
"'b' != 'c': path: root.top.l1.l2[1]",
e.difference)
self.assertIn(
"actual:\n{'top': {'l1': {'l2': ['c', 'a', 'd']}}}",
six.text_type(e))
self.assertIn(
"expected:\n{'top': {'l1': {'l2': ['a', 'b', 'c']}}}",
six.text_type(e))
else:
self.fail("This should have raised a mismatch exception")
def test_fail_on_dict_value(self):
expected = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2, 'c': 3}
}
}
}
actual = {
'top': {
'l1': {
'l2': {'a': 1, 'b': 2, 'c': 4}
}
}
}
try:
self.assertJsonEqual(expected, actual, 'test message')
except Exception as e:
self.assertEqual(
"3 != 4: path: root.top.l1.l2.c", e.difference)
self.assertIn("actual:\n{'top': {'l1': {'l2': {", six.text_type(e))
self.assertIn(
"expected:\n{'top': {'l1': {'l2': {", six.text_type(e))
self.assertIn(
"message: test message\n", six.text_type(e))
else:
self.fail("This should have raised a mismatch exception")
def test_compare_scalars(self):
with self.assertRaisesRegex(AssertionError, 'True != False'):
self.assertJsonEqual(True, False)
class BadLogTestCase(test.NoDBTestCase):
"""Make sure a mis-formatted debug log will get caught."""
def test_bad_debug_log(self):
self.assertRaises(KeyError,
LOG.debug, "this is a misformated %(log)s", {'nothing': 'nothing'})
class MatchTypeTestCase(test.NoDBTestCase):
def test_match_type_simple(self):
matcher = test.MatchType(dict)
self.assertEqual(matcher, {})
self.assertEqual(matcher, {"hello": "world"})
self.assertEqual(matcher, {"hello": ["world"]})
self.assertNotEqual(matcher, [])
self.assertNotEqual(matcher, [{"hello": "world"}])
self.assertNotEqual(matcher, 123)
self.assertNotEqual(matcher, "foo")
def test_match_type_object(self):
class Hello(object):
pass
class World(object):
pass
matcher = test.MatchType(Hello)
self.assertEqual(matcher, Hello())
self.assertNotEqual(matcher, World())
self.assertNotEqual(matcher, 123)
self.assertNotEqual(matcher, "foo")
class ContainKeyValueTestCase(test.NoDBTestCase):
def test_contain_key_value_normal(self):
matcher = test.ContainKeyValue('foo', 'bar')
self.assertEqual(matcher, {123: 'nova', 'foo': 'bar'})
self.assertNotEqual(matcher, {'foo': 123})
self.assertNotEqual(matcher, {})
def test_contain_key_value_exception(self):
matcher = test.ContainKeyValue('foo', 'bar')
# Raise TypeError
self.assertNotEqual(matcher, 123)
self.assertNotEqual(matcher, 'foo')
# Raise KeyError
self.assertNotEqual(matcher, {1: 2, '3': 4, 5: '6'})
self.assertNotEqual(matcher, {'bar': 'foo'})
class NovaExceptionReraiseFormatErrorTestCase(test.NoDBTestCase):
"""Test that format errors are reraised in tests."""
def test_format_error_in_nova_exception(self):
class FakeImageException(exception.NovaException):
msg_fmt = 'Image %(image_id)s has wrong type %(type)s.'
# wrong kwarg
ex = self.assertRaises(KeyError, FakeImageException,
bogus='wrongkwarg')
self.assertIn('image_id', six.text_type(ex))
# no kwarg
ex = self.assertRaises(KeyError, FakeImageException)
self.assertIn('image_id', six.text_type(ex))
# not enough kwargs
ex = self.assertRaises(KeyError, FakeImageException, image_id='image')
self.assertIn('type', six.text_type(ex))
class PatchExistsTestCase(test.NoDBTestCase):
def test_with_patch_exists_true(self):
"""Test that "with patch_exists" can fake the existence of a file
without changing other file existence checks, and that calls can
be asserted on the mocked method.
"""
self.assertFalse(os.path.exists('fake_file'))
with self.patch_exists('fake_file', True) as mock_exists:
self.assertTrue(os.path.exists('fake_file'))
self.assertTrue(os.path.exists(__file__))
self.assertFalse(os.path.exists('non-existent/file'))
self.assertIn(mock.call('fake_file'), mock_exists.mock_calls)
def test_with_patch_exists_false(self):
"""Test that "with patch_exists" can fake the non-existence of a file
without changing other file existence checks, and that calls can
be asserted on the mocked method.
"""
self.assertTrue(os.path.exists(__file__))
with self.patch_exists(__file__, False) as mock_exists:
self.assertFalse(os.path.exists(__file__))
self.assertTrue(os.path.exists(os.path.dirname(__file__)))
self.assertFalse(os.path.exists('non-existent/file'))
self.assertIn(mock.call(__file__), mock_exists.mock_calls)
@test.patch_exists('fake_file', True)
def test_patch_exists_decorator_true(self):
"""Test that @patch_exists can fake the existence of a file
without changing other file existence checks.
"""
self.assertTrue(os.path.exists('fake_file'))
self.assertTrue(os.path.exists(__file__))
self.assertFalse(os.path.exists('non-existent/file'))
@test.patch_exists(__file__, False)
def test_patch_exists_decorator_false(self):
"""Test that @patch_exists can fake the non-existence of a file
without changing other file existence checks.
"""
self.assertFalse(os.path.exists(__file__))
self.assertTrue(os.path.exists(os.path.dirname(__file__)))
self.assertFalse(os.path.exists('non-existent/file'))
@test.patch_exists('fake_file1', True)
@test.patch_exists('fake_file2', True)
@test.patch_exists(__file__, False)
def test_patch_exists_multiple_decorators(self):
"""Test that @patch_exists can be used multiple times on the
same method.
"""
self.assertTrue(os.path.exists('fake_file1'))
self.assertTrue(os.path.exists('fake_file2'))
self.assertFalse(os.path.exists(__file__))
# Check non-patched parameters
self.assertTrue(os.path.exists(os.path.dirname(__file__)))
self.assertFalse(os.path.exists('non-existent/file'))
class PatchOpenTestCase(test.NoDBTestCase):
fake_contents = "These file contents don't really exist"
def _test_patched_open(self):
"""Test that a selectively patched open can fake the contents of a
file while still allowing normal, real file operations.
"""
self.assertFalse(os.path.exists('fake_file'))
with open('fake_file') as f:
self.assertEqual(self.fake_contents, f.read())
# Test we can still open and read this file from within the
# same context. NOTE: We have to make sure we open the .py
# file not the corresponding .pyc file.
with open(__file__.rstrip('c')) as f:
this_file_contents = f.read()
self.assertIn("class %s(" % self.__class__.__name__,
this_file_contents)
self.assertNotIn("magic concatenated" "string",
this_file_contents)
# Test we can still create, write to, and then read from a
# temporary file, from within the same context.
tmp = tempfile.NamedTemporaryFile()
tmp_contents = str(uuid.uuid1())
with open(tmp.name, 'w') as f:
f.write(tmp_contents)
with open(tmp.name) as f:
self.assertEqual(tmp_contents, f.read())
return tmp.name
def test_with_patch_open(self):
"""Test that "with patch_open" can fake the contents of a file
without changing other file operations, and that calls can
be asserted on the mocked method.
"""
with self.patch_open('fake_file', self.fake_contents) as mock_open:
tmp_name = self._test_patched_open()
# Test we can make assertions about how the mock_open was called.
self.assertIn(mock.call('fake_file'), mock_open.mock_calls)
# The mock_open should get bypassed for non-patched path values:
self.assertNotIn(mock.call(__file__), mock_open.mock_calls)
self.assertNotIn(mock.call(tmp_name), mock_open.mock_calls)
@test.patch_open('fake_file', fake_contents)
def test_patch_open_decorator(self):
"""Test that @patch_open can fake the contents of a file
without changing other file operations.
"""
self._test_patched_open()