nbudin/google4r-checkout — pull request #12 by jamesmartin (2012-08-01 10:43:58+00:00)
Title: Raise UnknownNotificationType for non-XML Notification input

Was getting confusing `no method 'name' for nil:NilClass` errors in my server logs when testing on the Sandbox because I had Google Checkout configured to send simple key/value text pairs (instead of the expected XML) for the [SerialNumberNotification](https://developers.google.com/checkout/developer/Google_Checkout_XML_API_Notification_API#serial_number_notifications) callback.

This pull request makes `NotificationHandler#handle` raise a more informative `UnknownNotificationType` exception when parsing data that `REXML` can't turn into XML.