Fix the dags count filter in webserver home page (#34944)

* Fix the dags count filter in webserver home page

* Add a test to avoid breaking the count in the future

(cherry picked from commit 54e7e08)

airflow/www/views.py

@@ -840,7 +840,9 @@ def index(self):
 
             is_paused_count = dict(
                 session.execute(
-                    select(DagModel.is_paused, func.count(DagModel.dag_id)).group_by(DagModel.is_paused)
+                    all_dags.with_only_columns([DagModel.is_paused, func.count()]).group_by(
+                        DagModel.is_paused
+                    )
                 ).all()
             )
 

tests/www/views/test_views_home.py

@@ -70,6 +70,25 @@ def test_home(capture_templates, admin_client):
     assert templates[0].local_context["state_color"] == state_color_mapping
 
 
+@mock.patch("airflow.www.views.AirflowBaseView.render_template")
+def test_home_dags_count(render_template_mock, admin_client, working_dags, session):
+    from sqlalchemy import update
+
+    from airflow.models.dag import DagModel
+
+    def call_kwargs():
+        return render_template_mock.call_args.kwargs
+
+    admin_client.get("home", follow_redirects=True)
+    assert call_kwargs()["status_count_all"] == 4
+
+    update_stmt = update(DagModel).where(DagModel.dag_id == "filter_test_1").values(is_active=False)
+    session.execute(update_stmt)
+
+    admin_client.get("home", follow_redirects=True)
+    assert call_kwargs()["status_count_all"] == 3
+
+
 def test_home_status_filter_cookie(admin_client):
     with admin_client:
         admin_client.get("home", follow_redirects=True)