TMSS-1806: moved SchedulerSubsystemActivator into Subsystem Activator nested class for reuse.

SAS/TMSS/backend/services/scheduling/lib/dynamic_scheduling.py

@@ -94,7 +94,8 @@ class Scheduler:
         self._scheduling_thread_running = False
         self._do_schedule_event = Event()
         super().__init__()
-        SchedulerSubsystemActivator.deactivate() # make sure initial status is idle
+        # make sure initial status is idle
+        models.Subsystem.Activator('scheduler').deactivate()
 
     def start_scheduling(self):
         '''Prepares the scheduling_units, performs one full schedule computation, and start the scheduling loop and wait for a trigger.'''
@@ -206,7 +207,7 @@ class Scheduler:
 
     def schedule_fixed_time_scheduling_units(self):
         ''' Schedule all schedulable fixed_time scheduling units.'''
-        with SchedulerSubsystemActivator():
+        with models.Subsystem.Activator('scheduler'):
             # exclude units for inactive projects
             mark_scheduling_units_for_inactive_projects_unschedulable()
 
@@ -248,7 +249,7 @@ class Scheduler:
 
     def do_dynamic_schedule(self) -> models.SchedulingUnitBlueprint:
         '''do a full update of the schedule: schedule next scheduling unit and assign start stop times to remaining schedulable scheduling units'''
-        with SchedulerSubsystemActivator():
+        with models.Subsystem.Activator('scheduler'):
             logger.info("Updating (dynamic) schedule....")
 
             scheduled_unit = self.schedule_next_scheduling_unit()
@@ -816,34 +817,3 @@ def cancel_running_observation_if_needed_and_possible(candidate: ScoredSchedulin
             else:
                 logger.info('NOT cancelling subtask pk=%s trigger_priority=%s for triggered scheduling_unit pk=%s trigger_priority=%s because its priority is too low' %
                             (obs.pk, obs.project.trigger_priority, candidate.scheduling_unit.pk, candidate.scheduling_unit.project.trigger_priority))
-
-
-
-class SchedulerSubsystemActivator:
-    '''Helper class to activate/deactivate the 'scheduler' subsystem entry in the database.
-    By using the 'with'-context manager, it is guaranteed to deactivate the setting upon scope exit (thus also by exceptions)'''
-    @staticmethod
-    def activate():
-        '''activate the 'scheduler' subsystem status'''
-        try:
-            scheduler_subsytem = models.Subsystem.objects.get(name='scheduler')
-            scheduler_subsytem.status = models.SubsystemStatus.objects.get(value=models.SubsystemStatus.Choices.ACTIVE.value)
-            scheduler_subsytem.save()
-        except Exception as e:
-            logger.warning("Could not update scheduler subsystem status: %s", e)
-
-    @staticmethod
-    def deactivate():
-        '''deactivate the 'scheduler' subsystem status (idle)'''
-        try:
-            scheduler_subsytem = models.Subsystem.objects.get(name='scheduler')
-            scheduler_subsytem.status = models.SubsystemStatus.objects.get(value=models.SubsystemStatus.Choices.IDLE.value)
-            scheduler_subsytem.save()
-        except Exception as e:
-            logger.warning("Could not update scheduler subsystem status: %s", e)
-
-    def __enter__(self):
-        self.activate()
-
-    def __exit__(self, exc_type, exc_val, exc_tb):
-        self.deactivate()

SAS/TMSS/backend/src/tmss/tmssapp/models/specification.py

@@ -283,6 +283,37 @@ class Subsystem(NamedCommonPK):
     # superclass's name is primary key
     status = ForeignKey('SubsystemStatus', null=False, on_delete=PROTECT)
 
+    class Activator:
+        '''Helper class to activate/deactivate a subsystem entry in the database.
+        By using the 'with'-context manager, it is guaranteed to deactivate the setting upon scope exit (thus also by exceptions)'''
+        def __init__(self, subsystem_name: str):
+            self.subsystem_name = subsystem_name
+
+        def __update_state(self, status: str):
+            '''update the subsystem's status'''
+            try:
+                scheduler_subsytem = Subsystem.objects.get(name=self.subsystem_name)
+                scheduler_subsytem.status = SubsystemStatus.objects.get(value=status)
+                scheduler_subsytem.save()
+            except Exception as e:
+                logger.warning("Could not update %s subsystem status: %s", self.subsystem_name, e)
+
+        def activate(self):
+            '''activate the subsystem status'''
+            self.__update_state(SubsystemStatus.Choices.ACTIVE.value)
+
+        def deactivate(self):
+            '''deactivate the subsystem status'''
+            self.__update_state(SubsystemStatus.Choices.IDLE.value)
+
+        def __enter__(self):
+            '''activate the subsystem status upon entering the with-context'''
+            self.activate()
+
+        def __exit__(self, exc_type, exc_val, exc_tb):
+            '''deactivate the subsystem status upon exiting the with-context'''
+            self.deactivate()
+
 
 class TaskConnectorType(Model):
     ''' Describes the data type & format combinations a Task can accept or produce. The "role" is used to distinguish