Fix triggerer errors after Airflow 2 to 3 migration

airflow-core/src/airflow/jobs/triggerer_job_runner.py

@@ -649,7 +649,13 @@ def update_triggers(self, requested_trigger_ids: set[int]):
             )
             if new_trigger_orm.task_instance:
                 log_path = render_log_fname(ti=new_trigger_orm.task_instance)
-
+                if not new_trigger_orm.task_instance.dag_version_id:
+                    # This is to handle 2 to 3 upgrade where TI.dag_version_id can be none
+                    log.warning(
+                        "TaskInstance associated with Trigger has no associated Dag Version, skipping the trigger",
+                        ti_id=new_trigger_orm.task_instance.id,
+                    )
+                    continue
                 ser_ti = workloads.TaskInstance.model_validate(
                     new_trigger_orm.task_instance, from_attributes=True
                 )

airflow-core/tests/unit/jobs/test_triggerer_job.py

@@ -1140,6 +1140,38 @@ def test_update_triggers_prevents_duplicate_creation_queue_entries_with_multiple
     assert trigger_orm2.id in trigger_ids
 
 
+def test_update_triggers_skips_when_ti_has_no_dag_version(session, supervisor_builder, dag_maker):
+    """
+    Ensure supervisor skips creating a trigger when the linked TaskInstance has no dag_version_id.
+    """
+    with dag_maker(dag_id="test_no_dag_version"):
+        EmptyOperator(task_id="t1")
+    dr = dag_maker.create_dagrun()
+    ti = dr.task_instances[0]
+
+    # Create a Trigger and link it to the TaskInstance
+    trigger = TimeDeltaTrigger(datetime.timedelta(days=7))
+    trigger_orm = Trigger.from_object(trigger)
+    session.add(trigger_orm)
+    session.flush()
+
+    ti.trigger_id = trigger_orm.id
+    # Explicitly remove dag_version_id
+    ti.dag_version_id = None
+    session.merge(ti)
+    session.commit()
+
+    supervisor = supervisor_builder()
+
+    # Attempt to enqueue creation of this trigger
+    supervisor.update_triggers({trigger_orm.id})
+
+    # Assert that nothing was queued for creation and no subprocess writes happened
+    assert len(supervisor.creating_triggers) == 0
+    assert trigger_orm.id not in supervisor.running_triggers
+    supervisor.stdin.write.assert_not_called()
+
+
 class TestTriggererMessageTypes:
     def test_message_types_in_triggerer(self):
         """