deb-designate/designate/tests/test_hookpoints.py
Eric Larson d08a661812 Add the Hook Point API
Hook points allow installing a package that provide a decorator for some
function / method. The intent is to use it for organization specific
code.

The sample config contains an example.

See: https://review.openstack.org/171689/
Implements: blueprint hook-point-api
Change-Id: If98d9450cfd6b1a2a3cb23d8bc51940c1b6ee37a
2015-05-29 15:38:05 -05:00

145 lines
4.2 KiB
Python

# Copyright 2015 Rackspace Hosting.
#
# Author: Eric Larson <eric.larson@rackspace.com>
#
# 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.
from mock import Mock
from mock import patch
from oslo_config import cfg
from stevedore.hook import HookManager
from stevedore.extension import Extension
from designate.hookpoints import hook_point
from designate.hookpoints import BaseHook
from designate.tests import TestCase
class AddHook(BaseHook):
OPTS = [
cfg.Opt('bar'),
]
@property
def bar(self):
return cfg.CONF[self.group].bar
def hook(self, *args, **kw):
return self.hook_target(*args, **kw) + 1
def get_hook_manager(*hooks):
hooks = hooks or [AddHook]
group = 'hook_point:foo'
ext = [
Extension('designate_hook', 'foo', hook, hook(group))
for hook in hooks
]
return HookManager.make_test_instance(ext, 'designate_hook')
def inc(num):
return num + 1
class TestHookpoints(TestCase):
def setUp(self):
TestCase.setUp(self)
group = 'hook_point:foo'
self.CONF.register_group(cfg.OptGroup(group))
self.CONF.register_opts(BaseHook.OPTS, group=group)
def test_no_hookpoint_is_noop(self):
def doit(self, name):
return 'done: %s' % name
self.assertEqual(doit, hook_point('foo')(doit))
def test_hook_is_decorator(self):
hp = hook_point('foo')
hp.hook_manager = Mock(return_value=get_hook_manager())
assert hp(inc)(1) == 3
def test_apply_N_hooks(self):
hp = hook_point('foo')
hp.hook_manager = Mock(return_value=get_hook_manager(AddHook, AddHook))
assert hp(inc)(1) == 4
def test_hook_init(self):
hp = hook_point('foo')
# Make sure we set up our object when the hook point is
# applied to a function / method.
hp.find_name = Mock(return_value='foo.bar.baz')
hp.hook_manager = Mock(return_value=get_hook_manager())
hp.find_config = Mock(return_value={'enabled': True})
hp.update_config_opts = Mock()
hp(inc)
self.assertEqual(hp.name, 'foo.bar.baz')
self.assertEqual(hp.group, 'hook_point:foo.bar.baz')
hp.update_config_opts.assert_called_with(hp.group, hp.hooks)
class TestHookpointsConfigOpts(TestCase):
"""Make sure hooks add the necessary config opts.
"""
def test_hook_adds_config_opts(self):
hp = hook_point('foo')
hp.hook_manager = Mock(return_value=get_hook_manager())
hp(inc)
assert hp.group in self.CONF.keys()
class TestHookpointsEnabling(TestCase):
def setUp(self):
TestCase.setUp(self)
# NOTE: The options need to be added here via the test classes
# CONF in order to fall through
group = 'hook_point:foo'
self.CONF.register_group(cfg.OptGroup(group))
self.CONF.register_opts(BaseHook.OPTS, group=group)
@patch.object(hook_point, 'hook_manager',
Mock(return_value=get_hook_manager()))
def test_hook_disabled(self):
hp = hook_point('foo')
result_func = hp(inc)
# We should now have a config option we can set to disabled
self.config(disabled=True, group='hook_point:foo')
# The result is 2 so no extra add hook was applied
self.assertEqual(result_func(1), 2)
@patch.object(hook_point, 'hook_manager',
Mock(return_value=get_hook_manager()))
def test_hook_enabled_when_config_key_exists(self):
hp = hook_point('foo')
hp(inc)
# Add our config
self.config(bar='from config', group='hook_point:foo')
# reapply our hook
result_func = hp(inc)
# The result is 3 so the extra add hook was applied
self.assertEqual(result_func(1), 3)