Route conductor notification RPC to the same conductor

RPC continue_node_{deploy,clean} are called from a conductor handling
the node, so they don't have to go through the hash ring. This avoids
situation when take over happens in the middle of a deploy/clean step
processing, breaking it.

Eventually, we should stop using RPC for that at all, but that will be
a much more invasive change.

Story: #2008200
Task: #40984
Change-Id: I76293f8ec30d5957b99bdbce5b70e87e8378d135

ironic/conductor/rpcapi.py

@@ -202,6 +202,10 @@ class ConductorAPI(object):
         host = random.choice(list(ring.nodes))
         return self.topic + "." + host
 
+    def get_current_topic(self):
+        """Get RPC topic name for the current conductor."""
+        return self.topic + "." + CONF.host
+
     def can_send_create_port(self):
         """Return whether the RPCAPI supports the create_port method."""
         return self.client.can_send_version("1.41")

ironic/conductor/utils.py

@@ -828,7 +828,7 @@ def notify_conductor_resume_operation(task, operation):
     from ironic.conductor import rpcapi
     uuid = task.node.uuid
     rpc = rpcapi.ConductorAPI()
-    topic = rpc.get_topic_for(task.node)
+    topic = rpc.get_current_topic()
     # Need to release the lock to let the conductor take it
     task.release_resources()
     getattr(rpc, method)(task.context, uuid, topic=topic)

ironic/tests/unit/conductor/test_utils.py

@@ -1728,15 +1728,14 @@ class MiscTestCase(db_base.DbTestCase):
 
     @mock.patch.object(rpcapi.ConductorAPI, 'continue_node_deploy',
                        autospec=True)
-    @mock.patch.object(rpcapi.ConductorAPI, 'get_topic_for', autospec=True)
+    def test_notify_conductor_resume_operation(self, mock_rpc_call):
-    def test_notify_conductor_resume_operation(self, mock_topic,
+        self.config(host='fake-host')
-                                               mock_rpc_call):
-        mock_topic.return_value = 'topic'
         with task_manager.acquire(
                 self.context, self.node.uuid, shared=False) as task:
             conductor_utils.notify_conductor_resume_operation(task, 'deploy')
             mock_rpc_call.assert_called_once_with(
-                mock.ANY, task.context, self.node.uuid, topic='topic')
+                mock.ANY, task.context, self.node.uuid,
+                topic='ironic.conductor_manager.fake-host')
 
     @mock.patch.object(conductor_utils, 'notify_conductor_resume_operation',
                        autospec=True)

releasenotes/notes/notify-topic-451493784ce45e73.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Prevents a take over from happening in the middle of a deploy step
+    processing. This could happen if the RPC call ``continue_node_deploy``
+    is routed to a different conductor.