feat(robot-server): Support labware offset notifications (#19051)

Author: mjhuff

robot-server/robot_server/service/notifications/publishers/runs_publisher.py

@@ -31,6 +31,7 @@ class _EngineStateSlice:
     current_command: Optional[CommandPointer] = None
     recovery_target_command: Optional[CommandPointer] = None
     state_summary_status: Optional[EngineStatus] = None
+    state_summary_labware_offset_count: Optional[int] = None
 
 
 class RunsPublisher:
@@ -49,7 +50,7 @@ def __init__(
             [
                 self._handle_current_command_change,
                 self._handle_recovery_target_command_change,
-                self._handle_engine_status_change,
+                self._handle_relevant_engine_change,
             ]
         )
 
@@ -145,20 +146,30 @@ async def _handle_recovery_target_command_change(self) -> None:
                     new_recovery_target_command
                 )
 
-    async def _handle_engine_status_change(self) -> None:
-        """Publish a refetch flag if the engine status has changed."""
+    async def _handle_relevant_engine_change(self) -> None:
+        """Publish a refetch flag if relevant engine changes occur."""
         if self._run_hooks is not None and self._engine_state_slice is not None:
             new_state_summary = self._run_hooks.get_state_summary(
                 self._run_hooks.run_id
             )
 
-            if (
-                new_state_summary is not None
-                and self._engine_state_slice.state_summary_status
-                != new_state_summary.status
-            ):
-                self.publish_runs_advise_refetch(run_id=self._run_hooks.run_id)
-                self._engine_state_slice.state_summary_status = new_state_summary.status
+            if new_state_summary is not None:
+                if (
+                    self._engine_state_slice.state_summary_status
+                    != new_state_summary.status
+                ):
+                    self.publish_runs_advise_refetch(run_id=self._run_hooks.run_id)
+                    self._engine_state_slice.state_summary_status = (
+                        new_state_summary.status
+                    )
+
+                elif self._engine_state_slice.state_summary_labware_offset_count != len(
+                    new_state_summary.labwareOffsets
+                ):
+                    self.publish_runs_advise_refetch(run_id=self._run_hooks.run_id)
+                    self._engine_state_slice.state_summary_labware_offset_count = len(
+                        new_state_summary.labwareOffsets
+                    )
 
 
 _runs_publisher_accessor: AppStateAccessor[RunsPublisher] = AppStateAccessor[

robot-server/tests/service/notifications/publishers/test_runs_publisher.py

@@ -69,6 +69,7 @@ async def test_initialize(
     assert runs_publisher._engine_state_slice.current_command is None
     assert runs_publisher._engine_state_slice.recovery_target_command is None
     assert runs_publisher._engine_state_slice.state_summary_status is None
+    assert runs_publisher._engine_state_slice.state_summary_labware_offset_count is None
 
     notification_client.publish_advise_refetch.assert_any_call(topic=topics.RUNS)
     notification_client.publish_advise_refetch.assert_any_call(
@@ -171,10 +172,10 @@ async def test_handle_recovery_target_command_change(
     )
 
 
-async def test_handle_engine_status_change(
+async def test_handle_relevant_engine_change(
     runs_publisher: RunsPublisher, notification_client: Mock
 ) -> None:
-    """It should handle engine status changes appropriately."""
+    """It should handle relevant engine changes appropriately."""
     runs_publisher.start_publishing_for_run(
         run_id="1234",
         get_current_command=lambda _: make_command_pointer("command1"),
@@ -189,26 +190,68 @@ async def test_handle_engine_status_change(
 
     runs_publisher._run_hooks.run_id = "1234"
     runs_publisher._run_hooks.get_state_summary = MagicMock(
-        return_value=MagicMock(status=EngineStatus.IDLE)
+        return_value=MagicMock(status=EngineStatus.IDLE, labwareOffsets=[])
     )
     runs_publisher._engine_state_slice.state_summary_status = EngineStatus.IDLE
+    runs_publisher._engine_state_slice.state_summary_labware_offset_count = 0
 
-    await runs_publisher._handle_engine_status_change()
+    await runs_publisher._handle_relevant_engine_change()
 
     assert notification_client.publish_advise_refetch.call_count == 2
 
     runs_publisher._run_hooks.get_state_summary.return_value = MagicMock(
-        status=EngineStatus.RUNNING
+        status=EngineStatus.RUNNING, labwareOffsets=[]
     )
 
-    await runs_publisher._handle_engine_status_change()
+    await runs_publisher._handle_relevant_engine_change()
 
     notification_client.publish_advise_refetch.assert_any_call(topic=topics.RUNS)
     notification_client.publish_advise_refetch.assert_any_call(
         topic=f"{topics.RUNS}/1234"
     )
 
 
+async def test_handle_labware_offset_count_change(
+    runs_publisher: RunsPublisher, notification_client: Mock
+) -> None:
+    """It should handle labware offset count changes appropriately."""
+    runs_publisher.start_publishing_for_run(
+        run_id="1234",
+        get_current_command=lambda _: make_command_pointer("command1"),
+        get_recovery_target_command=AsyncMock(),
+        get_state_summary=AsyncMock(),
+    )
+
+    # todo(mm, 2024-05-21): We should test through the public interface of the subject,
+    # not through its private attributes.
+    assert runs_publisher._run_hooks
+    assert runs_publisher._engine_state_slice
+
+    initial_offsets = ["offset1", "offset2"]
+    runs_publisher._run_hooks.run_id = "1234"
+    runs_publisher._run_hooks.get_state_summary = MagicMock(
+        return_value=MagicMock(status=EngineStatus.IDLE, labwareOffsets=initial_offsets)
+    )
+    runs_publisher._engine_state_slice.state_summary_status = EngineStatus.IDLE
+    runs_publisher._engine_state_slice.state_summary_labware_offset_count = 2
+
+    await runs_publisher._handle_relevant_engine_change()
+    assert notification_client.publish_advise_refetch.call_count == 2
+
+    new_offsets = ["offset1", "offset2", "offset3"]
+    runs_publisher._run_hooks.get_state_summary.return_value = MagicMock(
+        status=EngineStatus.IDLE, labwareOffsets=new_offsets
+    )
+
+    await runs_publisher._handle_relevant_engine_change()
+
+    notification_client.publish_advise_refetch.assert_any_call(topic=topics.RUNS)
+    notification_client.publish_advise_refetch.assert_any_call(
+        topic=f"{topics.RUNS}/1234"
+    )
+    assert runs_publisher._engine_state_slice.state_summary_labware_offset_count == 3
+
+
 async def test_publish_pre_serialized_commannds_notif(
     runs_publisher: RunsPublisher, notification_client: Mock
 ) -> None: