From 549fac30eeefaa449df9bfdf58eb40a008e9fe75 Mon Sep 17 00:00:00 2001
From: Aleksey Kirilishin <54231417+avkirilishin@users.noreply.github.com>
Date: Sun, 3 Dec 2023 05:11:15 +0400
Subject: [PATCH] 34058: Fix UI Grid error when DAG has been removed. (#36028)

---
 airflow/www/views.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/airflow/www/views.py b/airflow/www/views.py
index c4230c1900bc2..f51fbb9e79c93 100644
--- a/airflow/www/views.py
+++ b/airflow/www/views.py
@@ -3013,6 +3013,9 @@ def legacy_graph(self):
     def graph(self, dag_id: str, session: Session = NEW_SESSION):
         """Redirect to the replacement - grid + graph. Kept for backwards compatibility."""
         dag = get_airflow_app().dag_bag.get_dag(dag_id, session=session)
+        if not dag:
+            flash(f'DAG "{dag_id}" seems to be missing from DagBag.', "error")
+            return redirect(url_for("Airflow.index"))
         dt_nr_dr_data = get_date_time_num_runs_dag_runs_form_data(request, session, dag)
         dttm = dt_nr_dr_data["dttm"]
         dag_run = dag.get_dagrun(execution_date=dttm)