- xhook(+Stream, +Event)[multifile, library(redis_streams)]
- This multifile predicate is called on certain stream events. Defined
events are:
- delivery_failed(Id, Group, Delivered)
- A message was delivered more than specified by max_deliveries/1
of xlisten_group/5. Id is the message id, Group the group and
Delivered the current delivery count. If the hooks fails, the
message is acknowledged using
XACK. From introduction
to streams:
"So once the deliveries counter reaches a given large number that you chose, it is probably wiser to put such messages in another stream and send a notification to the system administrator. This is basically the way that Redis streams implement the concept of the dead letter."