How to handle /_ah/bounce end point notification in App Engine application

Question

I am receiving /_ah/bounce messages in my App Engine application. This is visible to me from the App Engine logs in the Administration console.

There seems to be a lack of documentation around that and some digging into the App Engine Source Code seems to indicate the presence of classes like BounceNotification and BounceNotificationParser, which have only got introduced in the latest SDK 1.7.4.

Can someone explain:

1. Is this /_ah/bounce endpoint invoked only when a particular email could not get delivered and has bounced.

2. What settings do I need in my appengine-web.xml and web.xml to trap this /_ah/bounce end point?

3. How do I extract information on the bounce notification from the incoming request using the BounceNotification classes

Thank you in advance.

Answer 1

Those bounce calls were unwittingly exposed to you in the past. Now we released the bounce feature officially, so that you should be able to parse the bounce messages (easy!). For more details, please see the following doc:

Receiving Bounce Notification (Python|Java)