Order triggers by - TI priority_weight when assign unassigned triggers

airflow/models/trigger.py

@@ -22,6 +22,7 @@
 
 from sqlalchemy import Column, Integer, String, delete, func, or_, select, update
 from sqlalchemy.orm import Session, joinedload, relationship
+from sqlalchemy.sql.functions import coalesce
 
 from airflow.api_internal.internal_api_call import internal_api_call
 from airflow.models.base import Base
@@ -244,8 +245,9 @@ def assign_unassigned(
     def get_sorted_triggers(cls, capacity, alive_triggerer_ids, session):
         query = with_row_locks(
             select(cls.id)
+            .join(TaskInstance, cls.id == TaskInstance.trigger_id, isouter=False)
             .where(or_(cls.triggerer_id.is_(None), cls.triggerer_id.not_in(alive_triggerer_ids)))
-            .order_by(cls.created_date)
+            .order_by(coalesce(TaskInstance.priority_weight, 0).desc(), cls.created_date)
             .limit(capacity),
             session,
             skip_locked=True,

tests/models/test_trigger.py

@@ -171,19 +171,47 @@ def test_assign_unassigned(session, create_task_instance):
     trigger_on_healthy_triggerer = Trigger(classpath="airflow.triggers.testing.SuccessTrigger", kwargs={})
     trigger_on_healthy_triggerer.id = 1
     trigger_on_healthy_triggerer.triggerer_id = healthy_triggerer.id
+    session.add(trigger_on_healthy_triggerer)
+    ti_trigger_on_healthy_triggerer = create_task_instance(
+        task_id="ti_trigger_on_healthy_triggerer",
+        execution_date=time_now,
+        run_id="trigger_on_healthy_triggerer_run_id",
+    )
+    ti_trigger_on_healthy_triggerer.trigger_id = trigger_on_healthy_triggerer.id
+    session.add(ti_trigger_on_healthy_triggerer)
     trigger_on_unhealthy_triggerer = Trigger(classpath="airflow.triggers.testing.SuccessTrigger", kwargs={})
     trigger_on_unhealthy_triggerer.id = 2
     trigger_on_unhealthy_triggerer.triggerer_id = unhealthy_triggerer.id
+    session.add(trigger_on_unhealthy_triggerer)
+    ti_trigger_on_unhealthy_triggerer = create_task_instance(
+        task_id="ti_trigger_on_unhealthy_triggerer",
+        execution_date=time_now + datetime.timedelta(hours=1),
+        run_id="trigger_on_unhealthy_triggerer_run_id",
+    )
+    ti_trigger_on_unhealthy_triggerer.trigger_id = trigger_on_unhealthy_triggerer.id
+    session.add(ti_trigger_on_unhealthy_triggerer)
     trigger_on_killed_triggerer = Trigger(classpath="airflow.triggers.testing.SuccessTrigger", kwargs={})
     trigger_on_killed_triggerer.id = 3
     trigger_on_killed_triggerer.triggerer_id = finished_triggerer.id
+    session.add(trigger_on_killed_triggerer)
+    ti_trigger_on_killed_triggerer = create_task_instance(
+        task_id="ti_trigger_on_killed_triggerer",
+        execution_date=time_now + datetime.timedelta(hours=2),
+        run_id="trigger_on_killed_triggerer_run_id",
+    )
+    ti_trigger_on_killed_triggerer.trigger_id = trigger_on_killed_triggerer.id
+    session.add(ti_trigger_on_killed_triggerer)
     trigger_unassigned_to_triggerer = Trigger(classpath="airflow.triggers.testing.SuccessTrigger", kwargs={})
     trigger_unassigned_to_triggerer.id = 4
-    assert trigger_unassigned_to_triggerer.triggerer_id is None
-    session.add(trigger_on_healthy_triggerer)
-    session.add(trigger_on_unhealthy_triggerer)
-    session.add(trigger_on_killed_triggerer)
     session.add(trigger_unassigned_to_triggerer)
+    ti_trigger_unassigned_to_triggerer = create_task_instance(
+        task_id="ti_trigger_unassigned_to_triggerer",
+        execution_date=time_now + datetime.timedelta(hours=3),
+        run_id="trigger_unassigned_to_triggerer_run_id",
+    )
+    ti_trigger_unassigned_to_triggerer.trigger_id = trigger_unassigned_to_triggerer.id
+    session.add(ti_trigger_unassigned_to_triggerer)
+    assert trigger_unassigned_to_triggerer.triggerer_id is None
     session.commit()
     assert session.query(Trigger).count() == 4
     Trigger.assign_unassigned(new_triggerer.id, 100, health_check_threshold=30)
@@ -209,31 +237,101 @@ def test_assign_unassigned(session, create_task_instance):
     )
 
 
-def test_get_sorted_triggers(session, create_task_instance):
+def test_get_sorted_triggers_same_priority_weight(session, create_task_instance):
     """
-    Tests that triggers are sorted by the creation_date.
+    Tests that triggers are sorted by the creation_date if they have the same priority.
     """
+    old_execution_date = datetime.datetime(
+        2023, 5, 9, 12, 16, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
+    )
     trigger_old = Trigger(
         classpath="airflow.triggers.testing.SuccessTrigger",
         kwargs={},
-        created_date=datetime.datetime(
-            2023, 5, 9, 12, 16, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
-        ),
+        created_date=old_execution_date + datetime.timedelta(seconds=30),
     )
     trigger_old.id = 1
+    session.add(trigger_old)
+    TI_old = create_task_instance(
+        task_id="old",
+        execution_date=old_execution_date,
+        run_id="old_run_id",
+    )
+    TI_old.priority_weight = 1
+    TI_old.trigger_id = trigger_old.id
+    session.add(TI_old)
+
+    new_execution_date = datetime.datetime(
+        2023, 5, 9, 12, 17, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
+    )
     trigger_new = Trigger(
         classpath="airflow.triggers.testing.SuccessTrigger",
         kwargs={},
-        created_date=datetime.datetime(
-            2023, 5, 9, 12, 17, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
-        ),
+        created_date=new_execution_date + datetime.timedelta(seconds=30),
     )
     trigger_new.id = 2
-    session.add(trigger_old)
     session.add(trigger_new)
+    TI_new = create_task_instance(
+        task_id="new",
+        execution_date=new_execution_date,
+        run_id="new_run_id",
+    )
+    TI_new.priority_weight = 1
+    TI_new.trigger_id = trigger_new.id
+    session.add(TI_new)
+
     session.commit()
     assert session.query(Trigger).count() == 2
 
     trigger_ids_query = Trigger.get_sorted_triggers(capacity=100, alive_triggerer_ids=[], session=session)
 
     assert trigger_ids_query == [(1,), (2,)]
+
+
+def test_get_sorted_triggers_different_priority_weights(session, create_task_instance):
+    """
+    Tests that triggers are sorted by the priority_weight.
+    """
+    old_execution_date = datetime.datetime(
+        2023, 5, 9, 12, 16, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
+    )
+    trigger_old = Trigger(
+        classpath="airflow.triggers.testing.SuccessTrigger",
+        kwargs={},
+        created_date=old_execution_date + datetime.timedelta(seconds=30),
+    )
+    trigger_old.id = 1
+    session.add(trigger_old)
+    TI_old = create_task_instance(
+        task_id="old",
+        execution_date=old_execution_date,
+        run_id="old_run_id",
+    )
+    TI_old.priority_weight = 1
+    TI_old.trigger_id = trigger_old.id
+    session.add(TI_old)
+
+    new_execution_date = datetime.datetime(
+        2023, 5, 9, 12, 17, 14, 474415, tzinfo=pytz.timezone("Africa/Abidjan")
+    )
+    trigger_new = Trigger(
+        classpath="airflow.triggers.testing.SuccessTrigger",
+        kwargs={},
+        created_date=new_execution_date + datetime.timedelta(seconds=30),
+    )
+    trigger_new.id = 2
+    session.add(trigger_new)
+    TI_new = create_task_instance(
+        task_id="new",
+        execution_date=new_execution_date,
+        run_id="new_run_id",
+    )
+    TI_new.priority_weight = 2
+    TI_new.trigger_id = trigger_new.id
+    session.add(TI_new)
+
+    session.commit()
+    assert session.query(Trigger).count() == 2
+
+    trigger_ids_query = Trigger.get_sorted_triggers(capacity=100, alive_triggerer_ids=[], session=session)
+
+    assert trigger_ids_query == [(2,), (1,)]