Added exception catching to send default email if template file raise…

…s any exception (apache#24943)
XD-DENG · Jul 18, 2022 · fd6f537 · fd6f537
1 parent b7f51b9
commit fd6f537
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Showing 2 changed files with 41 additions and 2 deletions.
diff --git a/airflow/models/taskinstance.py b/airflow/models/taskinstance.py
@@ -2296,8 +2296,13 @@ def get_email_subject_content(
             def render(key: str, content: str) -> str:
                 if conf.has_option('email', key):
                     path = conf.get_mandatory_value('email', key)
-                    with open(path) as f:
-                        content = f.read()
+                    try:
+                        with open(path) as f:
+                            content = f.read()
+                    except FileNotFoundError:
+                        self.log.warning(f"Could not find email template file '{path!r}'. Using defaults...")
+                    except OSError:
+                        self.log.exception(f"Error while using email template '{path!r}'. Using defaults...")
                 return render_template_to_string(jinja_env.from_string(content), jinja_context)
 
             subject = render('subject_template', default_subject)

diff --git a/tests/models/test_taskinstance.py b/tests/models/test_taskinstance.py
@@ -1411,6 +1411,40 @@ def test_email_alert_with_config(self, mock_send_email, dag_maker):
         assert 'template: test_email_alert_with_config' == title
         assert 'template: test_email_alert_with_config' == body
 
+    @patch('airflow.models.taskinstance.send_email')
+    def test_email_alert_with_filenotfound_config(self, mock_send_email, dag_maker):
+        with dag_maker(dag_id='test_failure_email'):
+            task = BashOperator(
+                task_id='test_email_alert_with_config',
+                bash_command='exit 1',
+                email='to',
+            )
+        ti = dag_maker.create_dagrun(execution_date=timezone.utcnow()).task_instances[0]
+        ti.task = task
+
+        # Run test when the template file is not found
+        opener = mock_open(read_data='template: {{ti.task_id}}')
+        opener.side_effect = FileNotFoundError
+        with patch('airflow.models.taskinstance.open', opener, create=True):
+            try:
+                ti.run()
+            except AirflowException:
+                pass
+
+        (email_error, title_error, body_error), _ = mock_send_email.call_args
+
+        # Rerun task without any error and no template file
+        try:
+            ti.run()
+        except AirflowException:
+            pass
+
+        (email_default, title_default, body_default), _ = mock_send_email.call_args
+
+        assert email_error == email_default == 'to'
+        assert title_default == title_error
+        assert body_default == body_error
+
     @pytest.mark.parametrize("task_id", ["test_email_alert", "test_email_alert__1"])
     @patch('airflow.models.taskinstance.send_email')
     def test_failure_mapped_taskflow(self, mock_send_email, dag_maker, session, task_id):