Guaranteed-event-delivery

The guaranteed-event delivery feature enables the connector framework to ensure that events are never lost and never sent twice between the connector's event store, the JMS event store, and the destination's JMS queue. To become JMS-enabled, you must configure the connector DeliveryTransport standard property to JMS. Thus configured, the connector uses the JMS transport and all subsequent communication between the connector and the integration broker occurs through this transport. The JMS transport ensures that the messages are eventually delivered to their destination. Its role is to ensure that once a transactional queue session starts, the messages are cached there until a commit is issued; if a failure occurs or a rollback is issued, the messages are discarded.

Note:
Without use of the guaranteed-event delivery feature, a small window of possible failure exists between the time that the connector publishes an event (when the connector calls the gotApplEvent() method within its pollForEvents() method) and the time it updates the event store by deleting the event record (or perhaps updating it with an "event posted" status). If a failure occurs in this window, the event has been sent but its event record remains in the event store with an "in progress" status. When the connector restarts, it finds this event record still in the event store and sends it, resulting in the event being sent twice.

You can configure the guaranteed-event delivery feature for a JMS-enabled connector with, or without, a JMS event store. To configure the connector for guaranteed-event delivery, see Enabling guaranteed-event delivery.

If connector framework cannot deliver the business object to the ICS integration broker, then the object is placed on a FaultQueue (instead of UnsubscribedQueue and ErrorQueue) and generates a status indicator and a description of the problem. FaultQueue messages are written in MQRFH2 format.

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