[OVN] Enable "ha" API flag for OVN routers

The "ha" API flag is now enabled for the OVN routers. Because of the
current implementation, this flag must be always "True". When a new
router is created, this flag is always set. If an OVN router is
explicitly created or updated with "--no-ha" (ha=False), the server
will raise an InvalidInput exception.

Depends-On: https://review.opendev.org/c/openstack/neutron-tempest-plugin/+/911081

Closes-Bug: #2020823
Change-Id: I60ff33680dd5397a226a9051d51bfb0701f862b5

neutron/common/ovn/extensions.py

@@ -44,6 +44,7 @@ from neutron_lib.api.definitions import l3_enable_default_route_bfd
 from neutron_lib.api.definitions import l3_enable_default_route_ecmp
 from neutron_lib.api.definitions import l3_ext_gw_mode
 from neutron_lib.api.definitions import l3_ext_gw_multihoming
+from neutron_lib.api.definitions import l3_ext_ha_mode
 from neutron_lib.api.definitions import l3_flavors
 from neutron_lib.api.definitions import logging
 from neutron_lib.api.definitions import multiprovidernet
@@ -125,6 +126,7 @@ ML2_SUPPORTED_API_EXTENSIONS_OVN_L3 = [
     l3_ext_gw_multihoming.ALIAS,
     l3_enable_default_route_bfd.ALIAS,
     l3_enable_default_route_ecmp.ALIAS,
+    l3_ext_ha_mode.ALIAS,
 ]
 ML2_SUPPORTED_API_EXTENSIONS = [
     address_group.ALIAS,

neutron/db/ovn_l3_hamode_db.py

@@ -0,0 +1,35 @@
+# Copyright 2024 Red Hat, 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.
+
+from neutron_lib.callbacks import events
+from neutron_lib.callbacks import priority_group
+from neutron_lib.callbacks import registry
+from neutron_lib.callbacks import resources
+
+from neutron.db import l3_attrs_db
+
+
+@registry.has_registry_receivers
+class OVN_L3_HA_db_mixin(l3_attrs_db.ExtraAttributesMixin):
+    """Mixin class to add high availability capability to OVN routers."""
+
+    @registry.receives(resources.ROUTER, [events.PRECOMMIT_CREATE],
+                       priority_group.PRIORITY_ROUTER_EXTENDED_ATTRIBUTE)
+    def _precommit_router_create(self, resource, event, trigger, payload):
+        """Event handler to set ha flag creation."""
+        # NOTE(ralonsoh): OVN L3 router HA flag is mandatory and True always,
+        # enforced by ``OvnDriver.ha_support`` set to ``MANDATORY``. This flag
+        # cannot be updated.
+        router_db = payload.metadata['router_db']
+        self.set_extra_attr_value(router_db, 'ha', True)

neutron/services/l3_router/service_providers/driver_controller.py

@@ -139,7 +139,7 @@ class DriverController(object):
         # attributes via the API.
         try:
             _ensure_driver_supports_request(drv, payload.request_body)
-        except lib_exc.InvalidInput:
+        except lib_exc.InvalidInput as exc:
             # the current driver does not support this request, we need to
             # migrate to a new provider. populate the distributed and ha
             # flags from the previous state if not in the update so we can
@@ -162,7 +162,7 @@ class DriverController(object):
                       {'ha_flag': payload.request_body['ha'],
                        'distributed_flag':
                        payload.request_body['distributed']})
-            new_drv = self._attrs_to_driver(payload.request_body)
+            new_drv = self._attrs_to_driver(payload.request_body, exc=exc)
         if new_drv:
             LOG.debug("Router %(id)s migrating from %(old)s provider to "
                       "%(new)s provider.", {'id': payload.resource_id,
@@ -224,7 +224,7 @@ class DriverController(object):
         driver = self.drivers[provider['provider']]
         return driver
 
-    def _attrs_to_driver(self, router):
+    def _attrs_to_driver(self, router, exc=None):
         """Get a provider driver handle based on the ha/distributed flags."""
         distributed = _is_distributed(
             router.get('distributed', lib_const.ATTR_NOT_SPECIFIED))
@@ -236,6 +236,9 @@ class DriverController(object):
         for driver in drivers:
             if _is_driver_compatible(distributed, ha, driver):
                 return driver
+
+        if exc:
+            raise exc
         raise NotImplementedError(
             _("Could not find a service provider that supports "
               "distributed=%(d)s and ha=%(h)s") % {'d': distributed, 'h': ha}

neutron/services/ovn_l3/service_providers/ovn.py

@@ -26,6 +26,7 @@ from oslo_utils import excutils
 from neutron.common.ovn import constants as ovn_const
 from neutron.common.ovn import utils
 from neutron.conf.plugins.ml2.drivers.ovn import ovn_conf
+from neutron.db import ovn_l3_hamode_db as ovn_l3_ha
 from neutron.db import ovn_revision_numbers_db as db_rev
 from neutron.extensions import revisions
 from neutron.objects import router as l3_obj
@@ -37,7 +38,8 @@ LOG = logging.getLogger(__name__)
 
 
 @registry.has_registry_receivers
-class OvnDriver(base.L3ServiceProvider):
+class OvnDriver(base.L3ServiceProvider,
+                ovn_l3_ha.OVN_L3_HA_db_mixin):
     ha_support = base.MANDATORY
     distributed_support = base.MANDATORY
 

neutron/tests/unit/db/test_ovn_l3_hamode_db.py

@@ -0,0 +1,50 @@
+# Copyright 2024 Red Hat, Inc.
+# 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.
+
+from neutron_lib import context
+from neutron_lib.db import api as db_api
+from neutron_lib.plugins import constants as plugin_constants
+from neutron_lib.plugins import directory
+
+from neutron.db import ovn_l3_hamode_db
+from neutron.objects import router as router_obj
+from neutron.tests.unit.db import test_db_base_plugin_v2 as test_plugin
+from neutron.tests.unit.db import test_l3_dvr_db
+
+
+class FakeOVNL3Plugin(test_l3_dvr_db.FakeL3Plugin,
+                      ovn_l3_hamode_db.OVN_L3_HA_db_mixin):
+    pass
+
+
+class OVN_L3_HA_db_mixinTestCase(test_plugin.NeutronDbPluginV2TestCase):
+
+    def setUp(self, **kwargs):
+        super().setUp(plugin='ml2', **kwargs)
+        self.core_plugin = directory.get_plugin()
+        self.ctx = context.get_admin_context()
+        self.mixin = FakeOVNL3Plugin()
+        directory.add_plugin(plugin_constants.L3, self.mixin)
+
+    def _create_router(self, router):
+        with db_api.CONTEXT_WRITER.using(self.ctx):
+            return self.mixin._create_router_db(self.ctx, router, 'foo_tenant')
+
+    def test_create_router(self):
+        router_dict = {'name': 'foo_router', 'admin_state_up': True,
+                       'distributed': False}
+        router_db = self._create_router(router_dict)
+        router = router_obj.Router.get_object(self.ctx, id=router_db.id)
+        self.assertTrue(router.extra_attributes.ha)

neutron/tests/unit/services/ovn_l3/service_providers/test_driver_controller.py

@@ -0,0 +1,59 @@
+# Copyright 2024 Red Hat, 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.
+
+from unittest import mock
+
+from neutron_lib.callbacks import events
+from neutron_lib.callbacks import registry
+from neutron_lib import context
+from neutron_lib import exceptions as lib_exc
+
+from neutron.services.l3_router.service_providers import driver_controller \
+    as l3_driver_controller
+from neutron.services.ovn_l3.service_providers import driver_controller
+from neutron.tests.unit import testlib_api
+
+
+DB_PLUGIN_KLASS = 'neutron.db.db_base_plugin_v2.NeutronDbPluginV2'
+
+
+class TestDriverController(testlib_api.SqlTestCase):
+
+    def setUp(self):
+        super(TestDriverController, self).setUp()
+        self.setup_coreplugin(DB_PLUGIN_KLASS)
+        self.fake_l3 = mock.Mock()
+        self.dc = driver_controller.DriverController(self.fake_l3)
+        self.fake_l3.l3_driver_controller = self.dc
+        self.ctx = context.get_admin_context()
+
+    def test__update_router_provider_ha_mandatory(self):
+        test_dc = driver_controller.DriverController(self.fake_l3)
+        with mock.patch.object(registry, "publish") as mock_cb:
+            with mock.patch.object(test_dc, "get_provider_for_router"):
+                with mock.patch.object(
+                        l3_driver_controller,
+                        "_ensure_driver_supports_request") as _ensure:
+                    _ensure.side_effect = lib_exc.InvalidInput(
+                        error_message='message')
+                    self.assertRaises(
+                        lib_exc.InvalidInput,
+                        test_dc._update_router_provider,
+                        None, None, None,
+                        payload=events.DBEventPayload(
+                            None, request_body={'ha': False,
+                                                'distributed': True},
+                            states=({'flavor_id': None},))
+                    )
+                    mock_cb.assert_not_called()

releasenotes/notes/ovn-l3-router-ha-enablement-24c5a5f9fc763db1.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Enabled the ``ha`` API extension for OVN routers. Now the high
+    availability flag ``ha`` can be set and read for OVN routers. NOTE:
+    currently OVN routers are always HA; the flag is mandatory
+    and cannot be unset (but now can be read).