only stop if there are tasks to stop

services/director-v2/src/simcore_service_director_v2/modules/comp_scheduler/_base_scheduler.py

@@ -84,9 +84,9 @@
 _Current = CompTaskAtDB
 _MAX_WAITING_FOR_CLUSTER_TIMEOUT_IN_MIN: Final[int] = 10
 _SCHEDULER_INTERVAL: Final[datetime.timedelta] = datetime.timedelta(seconds=5)
-_TASK_NAME_TEMPLATE: Final[
-    str
-] = "computational-scheduler-{user_id}:{project_id}:{iteration}"
+_TASK_NAME_TEMPLATE: Final[str] = (
+    "computational-scheduler-{user_id}:{project_id}:{iteration}"
+)
 
 PipelineSchedulingTask: TypeAlias = asyncio.Task
 PipelineSchedulingWakeUpEvent: TypeAlias = asyncio.Event
@@ -219,9 +219,9 @@ async def run_new_pipeline(
         task, wake_up_event = self._start_scheduling(
             user_id, project_id, new_run.iteration
         )
-        self._scheduled_pipelines[
-            (user_id, project_id, new_run.iteration)
-        ] = ScheduledPipelineParams(scheduler_task=task, scheduler_waker=wake_up_event)
+        self._scheduled_pipelines[(user_id, project_id, new_run.iteration)] = (
+            ScheduledPipelineParams(scheduler_task=task, scheduler_waker=wake_up_event)
+        )
         await publish_project_log(
             self.rabbitmq_client,
             user_id,
@@ -653,20 +653,17 @@ async def _start_tasks(
         scheduled_tasks: dict[NodeID, CompTaskAtDB],
         comp_run: CompRunsAtDB,
         wake_up_callback: Callable[[], None],
-    ) -> None:
-        ...
+    ) -> None: ...
 
     @abstractmethod
     async def _get_tasks_status(
         self, user_id: UserID, tasks: list[CompTaskAtDB], comp_run: CompRunsAtDB
-    ) -> list[RunningState]:
-        ...
+    ) -> list[RunningState]: ...
 
     @abstractmethod
     async def _stop_tasks(
         self, user_id: UserID, tasks: list[CompTaskAtDB], comp_run: CompRunsAtDB
-    ) -> None:
-        ...
+    ) -> None: ...
 
     @abstractmethod
     async def _process_completed_tasks(
@@ -675,8 +672,7 @@ async def _process_completed_tasks(
         tasks: list[CompTaskAtDB],
         iteration: Iteration,
         comp_run: CompRunsAtDB,
-    ) -> None:
-        ...
+    ) -> None: ...
 
     @staticmethod
     def _build_exclusive_lock_key(*args, **kwargs) -> str:
@@ -816,8 +812,10 @@ async def _schedule_tasks_to_stop(
             project_id
         )
         # stop any remaining running task, these are already submitted
-        tasks_to_stop = [t for t in comp_tasks.values() if t.state in PROCESSING_STATES]
-        await self._stop_tasks(user_id, tasks_to_stop, comp_run)
+        if tasks_to_stop := [
+            t for t in comp_tasks.values() if t.state in PROCESSING_STATES
+        ]:
+            await self._stop_tasks(user_id, tasks_to_stop, comp_run)
 
     async def _schedule_tasks_to_start(  # noqa: C901
         self,
@@ -877,9 +875,9 @@ async def _schedule_tasks_to_start(  # noqa: C901
                 RunningState.WAITING_FOR_CLUSTER,
             )
             for task in tasks_ready_to_start:
-                comp_tasks[
-                    NodeIDStr(f"{task}")
-                ].state = RunningState.WAITING_FOR_CLUSTER
+                comp_tasks[NodeIDStr(f"{task}")].state = (
+                    RunningState.WAITING_FOR_CLUSTER
+                )
 
         except ComputationalBackendOnDemandNotReadyError as exc:
             _logger.info(
@@ -901,9 +899,9 @@ async def _schedule_tasks_to_start(  # noqa: C901
                 RunningState.WAITING_FOR_CLUSTER,
             )
             for task in tasks_ready_to_start:
-                comp_tasks[
-                    NodeIDStr(f"{task}")
-                ].state = RunningState.WAITING_FOR_CLUSTER
+                comp_tasks[NodeIDStr(f"{task}")].state = (
+                    RunningState.WAITING_FOR_CLUSTER
+                )
         except ClustersKeeperNotAvailableError:
             _logger.exception("Unexpected error while starting tasks:")
             await publish_project_log(