Add run_type tag to dagrun.duration.failed timeout metric

When a Dag run timed out, the scheduler emitted dagrun.duration.failed with
only a dag_id tag, while every other dagrun.duration.* metric (emitted by
DagRun._emit_duration_stats_for_finished_state) also carries run_type. This
made the timeout path inconsistent and dropped run_type from dashboards and
alerts for timed-out runs.

Emit the metric with dag_run.stats_tags so it includes both dag_id and
run_type, matching the canonical completion path.

closes: #64765

Author: deepinsight coder

airflow-core/newsfragments/64765.bugfix.rst

@@ -0,0 +1 @@
+Add the ``run_type`` tag to the ``dagrun.duration.failed`` metric emitted when a Dag run times out, making it consistent with the same metric emitted on normal Dag run completion.

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

@@ -2457,7 +2457,9 @@ def _schedule_dag_run(
                 stats.timing(
                     "dagrun.duration.failed",
                     duration,
-                    tags={"dag_id": dag_run.dag_id},
+                    # Include ``run_type`` (via stats_tags) so the timeout path matches
+                    # DagRun._emit_duration_stats_for_finished_state; see #64765.
+                    tags=dag_run.stats_tags,
                 )
             return callback_to_execute
 

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

@@ -3835,6 +3835,45 @@ def test_dagrun_timeout_fails_run(self, dag_maker):
         session.rollback()
         session.close()
 
+    @mock.patch("airflow._shared.observability.metrics.stats._get_backend")
+    def test_dagrun_timeout_duration_metric_has_run_type(self, mock_get_backend, dag_maker):
+        """
+        The ``dagrun.duration.failed`` metric emitted when a Dag run times out must carry the
+        ``run_type`` tag, matching the metric emitted on normal Dag run completion via
+        ``DagRun._emit_duration_stats_for_finished_state``. Regression test for #64765.
+        """
+        mock_stats = mock.MagicMock(spec=StatsLogger)
+        mock_get_backend.return_value = mock_stats
+
+        session = settings.Session()
+        with dag_maker(
+            dag_id="test_dagrun_timeout_duration_metric",
+            dagrun_timeout=datetime.timedelta(seconds=60),
+            session=session,
+        ):
+            EmptyOperator(task_id="dummy")
+
+        dr = dag_maker.create_dagrun(start_date=timezone.utcnow() - datetime.timedelta(days=1))
+
+        scheduler_job = Job()
+        self.job_runner = SchedulerJobRunner(job=scheduler_job)
+
+        self.job_runner._schedule_dag_run(dr, session)
+        session.flush()
+
+        session.refresh(dr)
+        assert dr.state == State.FAILED
+
+        # The timing call must include both dag_id and run_type (dag_run.stats_tags), not just dag_id.
+        mock_stats.timing.assert_any_call(
+            "dagrun.duration.failed",
+            mock.ANY,
+            tags={"dag_id": dr.dag_id, "run_type": dr.run_type},
+        )
+
+        session.rollback()
+        session.close()
+
     def test_dagrun_timeout_fails_run_and_update_next_dagrun(self, dag_maker):
         """
         Test that dagrun timeout fails run and update the next dagrun