[nova-k8s/placement-k8s] Add placement interface

nova-scheduler errors out if placement service is
not available even if the container healthchecks
shows active. Add placement integration in nova-k8s
to ensure placement is defined in the bundle/tf plan

Add ServiceReadinessProviderHandler in placement-k8s
and corresponding RequiresHandler in nova-k8s.

Fixes: #2097327
Change-Id: Ica072b98c4668c6248702ca680b2885c4d542e23

charms/nova-k8s/.sunbeam-build.yaml

@@ -10,6 +10,7 @@ external-libraries:
   - charms.tempo_k8s.v1.charm_tracing
 internal-libraries:
   - charms.keystone_k8s.v1.identity_service
+  - charms.sunbeam_libs.v0.service_readiness
 templates:
   - parts/section-database
   - parts/database-connection

charms/nova-k8s/charmcraft.yaml

@@ -93,6 +93,8 @@ requires:
     interface: rabbitmq
   identity-service:
     interface: keystone
+  placement:
+    interface: placement
   cloud-compute:
     interface: nova-compute
     optional: true

charms/nova-k8s/src/charm.py

@@ -543,6 +543,13 @@ class NovaOperatorCharm(sunbeam_charm.OSBaseOperatorAPICharm):
             [NOVA_API_INGRESS_NAME, NOVA_SPICEPROXY_INGRESS_NAME],
         )
         handlers.append(self.traefik_route_internal)
+        self.placement_svc = sunbeam_rhandlers.ServiceReadinessRequiresHandler(
+            self,
+            "placement",
+            self.configure_charm,
+            "placement" in self.mandatory_relations,
+        )
+        handlers.append(self.placement_svc)
 
         return handlers
 

charms/nova-k8s/tests/unit/test_nova_charm.py

@@ -94,6 +94,10 @@ class TestNovaOperatorCharm(test_utils.CharmTestCase):
             app_data={"external_host": "dummy-ip", "scheme": "http"},
         )
 
+    def add_placement_relation(self, harness: Harness) -> None:
+        """Add placement relation."""
+        harness.add_relation("placement", "nova", app_data={"ready": "true"})
+
     def add_db_relation(self, harness: Harness, name: str) -> str:
         """Add db relation."""
         rel_id = harness.add_relation(name, "mysql")
@@ -117,6 +121,7 @@ class TestNovaOperatorCharm(test_utils.CharmTestCase):
         # this adds all the default/common relations
         test_utils.add_all_relations(self.harness)
         self.add_complete_ingress_relation(self.harness)
+        self.add_placement_relation(self.harness)
 
         # but nova has some extra db relations, so add them manually here
         rel_id = self.add_db_relation(self.harness, "api-database")

charms/placement-k8s/.sunbeam-build.yaml

@@ -8,6 +8,7 @@ external-libraries:
   - charms.tempo_k8s.v1.charm_tracing
 internal-libraries:
   - charms.keystone_k8s.v1.identity_service
+  - charms.sunbeam_libs.v0.service_readiness
 templates:
   - parts/database-connection
   - parts/database-connection-settings

charms/placement-k8s/src/charm.py

@@ -30,7 +30,11 @@ import ops.pebble
 import ops_sunbeam.charm as sunbeam_charm
 import ops_sunbeam.container_handlers as sunbeam_chandlers
 import ops_sunbeam.core as sunbeam_core
+import ops_sunbeam.relation_handlers as sunbeam_rhandlers
 import ops_sunbeam.tracing as sunbeam_tracing
+from ops.charm import (
+    RelationEvent,
+)
 from ops.framework import (
     StoredState,
 )
@@ -86,6 +90,44 @@ class PlacementOperatorCharm(sunbeam_charm.OSBaseOperatorAPICharm):
             )
         ]
 
+    def get_relation_handlers(
+        self, handlers: list[sunbeam_rhandlers.RelationHandler] | None = None
+    ) -> list[sunbeam_rhandlers.RelationHandler]:
+        """Relation handlers for the service."""
+        handlers = handlers or []
+        self.svc_ready_handler = (
+            sunbeam_rhandlers.ServiceReadinessProviderHandler(
+                self,
+                "placement",
+                self.handle_readiness_request_from_event,
+            )
+        )
+        handlers.append(self.svc_ready_handler)
+
+        handlers = super().get_relation_handlers(handlers)
+        return handlers
+
+    def post_config_setup(self):
+        """Configuration steps after services have been setup."""
+        super().post_config_setup()
+        self.set_readiness_on_related_units()
+
+    def handle_readiness_request_from_event(
+        self, event: RelationEvent
+    ) -> None:
+        """Set service readiness in relation data."""
+        self.svc_ready_handler.interface.set_service_status(
+            event.relation, self.bootstrapped()
+        )
+
+    def set_readiness_on_related_units(self) -> None:
+        """Set service readiness on placement related units."""
+        logger.debug(
+            "Set service readiness on all connected placement relations"
+        )
+        for relation in self.framework.model.relations["placement"]:
+            self.svc_ready_handler.interface.set_service_status(relation, True)
+
     @property
     def container_configs(self) -> List[sunbeam_core.ContainerConfigFile]:
         """Container configurations for the operator."""

tests/all-k8s/smoke.yaml.j2

@@ -418,6 +418,8 @@ relations:
   - nova:traefik-route-internal
 - - keystone:send-ca-cert
   - nova:receive-ca-cert
+- - placement:placement
+  - nova:placement
 
 - - mysql:database
   - placement:database

tests/core/smoke.yaml.j2

@@ -188,6 +188,8 @@ relations:
   - nova:traefik-route-internal
 - - keystone:send-ca-cert
   - nova:receive-ca-cert
+- - placement:placement
+  - nova:placement
 
 - - mysql:database
   - placement:database

tests/tempest/smoke.yaml.j2

@@ -183,6 +183,8 @@ relations:
   - nova:traefik-route-internal
 - - keystone:send-ca-cert
   - nova:receive-ca-cert
+- - placement:placement
+  - nova:placement
 
 - - mysql:database
   - placement:database