Returning a Message to the Queue

A subscriber can also explicitly release a message back to the queue. AMPS returns the message to the queue, and redelivers the message just as though the lease had expired. To do this, the subscriber sends a sow_delete command with the bookmark of the message to release and the cancel option.

When using automatic acknowledgments and the asynchronous API, AMPS will cancel a message if an exception is thrown from the message handler.

To return a message to the queue, you can build a sow_delete acknowledgment using the Command class, or pass an option to the ack() method on the message.

Option	Result
cancel	Returns the message to the queue.
expire	Immediately expires the message from the queue.

For example, to return a message to a queue, call ack() on the message and pass the cancel option.

message.ack("cancel");