Mailgun: fix webhook error with null delivery-status

Mailgun now sometimes posts `"delivery-status": null` 
in the tracking event payload. Avoid raising an AttributeError
when that occurs.

Fixes #361

CHANGELOG.rst

@@ -44,6 +44,13 @@ Features
  (Thanks to `@Arondit`_ for the implementation.)
 
 
+Fixes
+~~~~~
+
+* **Mailgun:** Avoid an error when Mailgun posts null delivery-status
+ to the event tracking webhook. (Thanks to `@izimobil`_ for the fix.)
+
+
 v10.2
 -----
 
@@ -1595,6 +1602,7 @@ Features
 .. _@Flexonze: https:/Flexonze
 .. _@gdvalderrama: https:/gdvalderrama
 .. _@Honza-m: https:/Honza-m
+.. _@izimobil: https:/izimobil
 .. _@janneThoft: https:/janneThoft
 .. _@jc-ee: https:/jc-ee
 .. _@joshkersey: https:/joshkersey

anymail/webhooks/mailgun.py

@@ -172,12 +172,12 @@ def esp_to_anymail_event(self, esp_event):
 
  try:
  delivery_status = event_data["delivery-status"]
- except KeyError:
- description = None
- mta_response = None
- else:
+ # if delivery_status is None, an AttributeError will be raised
  description = delivery_status.get("description")
  mta_response = delivery_status.get("message")
+ except (KeyError, AttributeError):
+ description = None
+ mta_response = None
 
  if "reason" in event_data:
  reject_reason = self.reject_reasons.get(

tests/test_mailgun_webhooks.py

@@ -630,6 +630,22 @@ def test_clicked_event(self):
  self.assertEqual(event.event_type, "clicked")
  self.assertEqual(event.click_url, "https://example.com/test")
 
+ def test_delivery_status_is_none_event(self):
+ raw_event = mailgun_sign_payload(
+ {
+ "event-data": {
+ "event": "accepted",
+ "delivery-status": None,
+ }
+ }
+ )
+ response = self.client.post(
+ "/anymail/mailgun/tracking/",
+ data=json.dumps(raw_event),
+ content_type="application/json",
+ )
+ self.assertEqual(response.status_code, 200)
+
 
 @tag("mailgun")
 @override_settings(ANYMAIL_MAILGUN_WEBHOOK_SIGNING_KEY=TEST_WEBHOOK_SIGNING_KEY)