From 7da04e96f11e11677d4d4471dff43f30acd55f50 Mon Sep 17 00:00:00 2001
From: Pierre Jeambrun <pierrejbrun@gmail.com>
Date: Mon, 3 Aug 2026 07:31:37 +0200
Subject: [PATCH] [v3-3-test] Fix Dag run duration stats crash on PostgreSQL
 14+ (#70833)

PostgreSQL 14 changed EXTRACT(epoch FROM ...) to return numeric rather than double precision, so DagRun.duration is hydrated as Decimal on Postgres 14+. The duration-stats percentile interpolation then multiplies a Decimal by a float, which Python disallows, so the Dag run stats endpoint raises a TypeError for any Dag that has completed runs.
(cherry picked from commit 30006eb9f8c76b42beb349b5c1d859678a641253)

Co-authored-by: Pierre Jeambrun <pierrejbrun@gmail.com>
---
 .../core_api/services/ui/dag_run.py           |  4 +-
 .../core_api/services/ui/test_dag_run.py      | 41 +++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 airflow-core/tests/unit/api_fastapi/core_api/services/ui/test_dag_run.py

diff --git a/airflow-core/src/airflow/api_fastapi/core_api/services/ui/dag_run.py b/airflow-core/src/airflow/api_fastapi/core_api/services/ui/dag_run.py
index a9ba75417c87b..2a3ab18325239 100644
--- a/airflow-core/src/airflow/api_fastapi/core_api/services/ui/dag_run.py
+++ b/airflow-core/src/airflow/api_fastapi/core_api/services/ui/dag_run.py
@@ -35,7 +35,9 @@ def compute_duration_stats(durations: list[float]) -> DurationStats | None:
     if not durations:
         return None
 
-    sorted_d = sorted(durations)
+    # On Postgres 14+, DagRun.duration comes back as Decimal (EXTRACT(epoch ...) returns
+    # numeric); coerce to float so the percentile interpolation below (Decimal * float) works.
+    sorted_d = sorted(float(d) for d in durations)
 
     counts = Counter(round(d) for d in sorted_d)
     max_count = max(counts.values())
diff --git a/airflow-core/tests/unit/api_fastapi/core_api/services/ui/test_dag_run.py b/airflow-core/tests/unit/api_fastapi/core_api/services/ui/test_dag_run.py
new file mode 100644
index 0000000000000..afa9c5277e256
--- /dev/null
+++ b/airflow-core/tests/unit/api_fastapi/core_api/services/ui/test_dag_run.py
@@ -0,0 +1,41 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+from __future__ import annotations
+
+from decimal import Decimal
+
+import pytest
+
+from airflow.api_fastapi.core_api.services.ui.dag_run import compute_duration_stats
+
+
+@pytest.mark.parametrize("cast", [float, Decimal], ids=["float", "decimal"])
+def test_compute_duration_stats_handles_float_and_decimal(cast):
+    """Durations arrive as Decimal on Postgres 14+ (EXTRACT(epoch ...) returns numeric) and as
+    float/int on other backends; the stats must compute for either without raising TypeError."""
+    durations = [cast(v) for v in (10, 20, 20, 30, 40)]
+
+    stats = compute_duration_stats(durations)
+
+    assert stats is not None
+    assert stats.mean == 24.0
+    assert stats.mode == 20.0
+    assert stats.p50 == 20.0
+    assert stats.p90 == 36.0
+    assert stats.p95 == 38.0
+    assert stats.p99 == 39.6