[FIX] mail_tracking_mailgun: discard non Odoo events

When we use the same Mailgun domain for other services, the email events
for those services we'll be pushed to the Odoo controller as well. We
want to discard them as they're useless to us.

Aside from that, in the case a wrong db is called to the controller, we
better logging the failed request is going to be more useful than
raising an error.

mail_tracking_mailgun/models/mail_tracking_email.py

@@ -168,8 +168,18 @@ class MailTrackingEmail(models.Model):
         In https://documentation.mailgun.com/en/latest/api-events.html#event-structure
         you can read the event payload format as obtained from webhooks or calls to API.
         """
+        # Just ignore these events, as they will be from another system using the same
+        # smtp domain
+        if "odoo_db" not in event_data["user-variables"]:
+            _logger.debug(f"Mailgun: dropping not Odoo event: {event_data}")
+            return
+        # Don't fail too hard, just drop and log the issue
         if event_data["user-variables"]["odoo_db"] != self.env.cr.dbname:
-            raise ValidationError(_("Wrong database for event!"))
+            _logger.error(
+                f"Mailgun: event for DB {event_data['user-variables']['odoo_db']} "
+                f"received in DB {self.env.cr.dbname}: {event_data}"
+            )
+            return
         # Do nothing if event was already processed
         mailgun_id = event_data["id"]
         db_event = self.env["mail.tracking.event"].search(

mail_tracking_mailgun/tests/test_mailgun.py

@@ -190,11 +190,21 @@ class TestMailgun(TransactionCase):
         with self._request_mock(), self.assertRaises(MissingError):
             self.MailTrackingController.mail_tracking_mailgun_webhook()
 
-    @mute_logger("odoo.addons.mail_tracking_mailgun.models.mail_tracking_email")
     def test_tracking_wrong_db(self):
         self.event["user-variables"]["odoo_db"] = "%s_nope" % self.env.cr.dbname
-        with self._request_mock(), self.assertRaises(ValidationError):
+        with self._request_mock(), self.assertLogs(level="ERROR") as log_catcher:
             self.MailTrackingController.mail_tracking_mailgun_webhook()
+        self.assertIn(
+            f"Mailgun: event for DB {self.env.cr.dbname}_nope "
+            f"received in DB {self.env.cr.dbname}",
+            log_catcher.output[0],
+        )
+
+    def test_tracking_not_odoo_event(self):
+        self.event["user-variables"].pop("odoo_db")
+        with self._request_mock(), self.assertLogs(level="DEBUG") as log_catcher:
+            self.MailTrackingController.mail_tracking_mailgun_webhook()
+        self.assertIn("Mailgun: dropping not Odoo event", log_catcher.output[-1:][0])
 
     # https://documentation.mailgun.com/en/latest/user_manual.html#tracking-deliveries
     def test_event_delivered(self):