charm-trilio-wlm/unit_tests/test_trilio_wlm_handlers.py

# 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 mock

import reactive.trilio_wlm_handlers as handlers

import charms_openstack.test_utils as test_utils

_when_args = {}
_when_not_args = {}


def mock_hook_factory(d):
    def mock_hook(*args, **kwargs):
        def inner(f):
            # remember what we were passed.  Note that we can't actually
            # determine the class we're attached to, as the decorator only gets
            # the function.
            try:
                d[f.__name__].append(dict(args=args, kwargs=kwargs))
            except KeyError:
                d[f.__name__] = [dict(args=args, kwargs=kwargs)]
            return f

        return inner

    return mock_hook


class TestDmapiHandlers(test_utils.PatchHelper):
    @classmethod
    def setUpClass(cls):
        cls._patched_when = mock.patch(
            "charms.reactive.when", mock_hook_factory(_when_args)
        )
        cls._patched_when_started = cls._patched_when.start()
        cls._patched_when_not = mock.patch(
            "charms.reactive.when_not", mock_hook_factory(_when_not_args)
        )
        cls._patched_when_not_started = cls._patched_when_not.start()
        # force requires to rerun the mock_hook decorator:
        # try except is Python2/Python3 compatibility as Python3 has moved
        # reload to importlib.
        try:
            reload(handlers)
        except NameError:
            import importlib

            importlib.reload(handlers)

    @classmethod
    def tearDownClass(cls):
        cls._patched_when.stop()
        cls._patched_when_started = None
        cls._patched_when = None
        cls._patched_when_not.stop()
        cls._patched_when_not_started = None
        cls._patched_when_not = None
        # and fix any breakage we did to the module
        try:
            reload(handlers)
        except NameError:
            import importlib

            importlib.reload(handlers)

    def setUp(self):
        self._patches = {}
        self._patches_start = {}

    def tearDown(self):
        for k, v in self._patches.items():
            v.stop()
            setattr(self, k, None)
        self._patches = None
        self._patches_start = None

    def patch(self, obj, attr, return_value=None, side_effect=None):
        mocked = mock.patch.object(obj, attr)
        self._patches[attr] = mocked
        started = mocked.start()
        started.return_value = return_value
        started.side_effect = side_effect
        self._patches_start[attr] = started
        setattr(self, attr, started)

    def test_registered_hooks(self):
        # test that the hooks actually registered the relation expressions that
        # are meaningful for this interface: this is to handle regressions.
        # The keys are the function names that the hook attaches to.
        when_patterns = {
            "render_config": (
                "shared-db.available",
                "identity-service.available",
                "amqp.available",
            ),
            "init_db": ("config.rendered",),
            "cluster_connected": ("ha.connected",),
            "register_endpoints_and_request_notification": (
                "identity-service.connected",),
        }
        when_not_patterns = {}
        # check the when hooks are attached to the expected functions
        for t, p in [
            (_when_args, when_patterns),
            (_when_not_args, when_not_patterns),
        ]:
            for f, args in t.items():
                # check that function is in patterns
                self.assertTrue(f in p.keys(), "{} not found".format(f))
                # check that the lists are equal
                lst = []
                for a in args:
                    lst += a["args"][:]
                self.assertEqual(
                    sorted(lst),
                    sorted(p[f]),
                    "{}: incorrect state registration".format(f),
                )

    def test_render(self):
        wlm_charm = mock.MagicMock()
        self.patch_object(
            handlers.charm, "provide_charm_instance", new=mock.MagicMock()
        )
        self.provide_charm_instance().__enter__.return_value = wlm_charm
        self.provide_charm_instance().__exit__.return_value = None
        args = "args"
        handlers.render_config(args)
        wlm_charm.upgrade_if_available.assert_called_once_with((args,))
        wlm_charm.render_with_interfaces.assert_called_once_with((args,))
        wlm_charm.assess_status.assert_called_once_with()

    def test_register_endpoints_and_request_notification(self):
        wlm_charm = mock.MagicMock()
        _service_type = "workloadmgr"
        _region = "RegionOne"
        _public_url = "http://trilio-wlm-public"
        _internal_url = "http://trilio-wlm-internal"
        _admin_url = "http://trilio-wlm-admin"
        _trustee_role = "_trustee_role_"
        wlm_charm.service_type = _service_type
        wlm_charm.region = _region
        wlm_charm.public_url = _public_url
        wlm_charm.internal_url = _internal_url
        wlm_charm.admin_url = _admin_url
        wlm_charm.options.trustee_role = _trustee_role
        self.patch_object(
            handlers.charm, "provide_charm_instance", new=mock.MagicMock()
        )
        self.provide_charm_instance().__enter__.return_value = wlm_charm
        self.provide_charm_instance().__exit__.return_value = None
        wlm_charm.required_services = ["foo", "bar"]
        identity_service = mock.MagicMock()
        handlers.register_endpoints_and_request_notification(
            identity_service)
        identity_service.request_notification.assert_called_once_with(
            ["foo", "bar"]
        )
        identity_service.register_endpoints.assert_called_once_with(
            _service_type,
            _region,
            _public_url,
            _internal_url,
            _admin_url,
            requested_roles=[_trustee_role]
        )