Ordered Consumers #789
Ordered Consumers #789
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Signed-off-by: R.I.Pienaar <[email protected]>
Signed-off-by: R.I.Pienaar <[email protected]>
This introduces ordered consumers. They are a convenience over ephemeral, no ack, no redelivery, only deliver things in strict order setups. We have the swap out when we detect gaps and change out the underlying sub and JetStream consumer, and we process the heartbeats as well, detecting gaps at the end or if a stream or consumer is pulled out from underneath of us. Signed-off-by: Derek Collison <[email protected]>
Signed-off-by: Derek Collison <[email protected]>
Signed-off-by: Derek Collison <[email protected]>
Signed-off-by: Derek Collison <[email protected]>
Signed-off-by: Derek Collison <[email protected]>
| @@ -1180,37 +1292,44 @@ func (js *js) subscribe(subj, queue string, cb MsgHandler, ch chan *Msg, isSync | |||
| return nil, ErrSubjectMismatch | |||
| } | |||
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| // Update attached status. | |||
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What if you add a LABEL before processing of switch{} where we have case info != nil, then line 1288 (after calling js.ConsumerInfo() when return is OK, we could here simply make sure that the subscription is destroyed,
set deliver to info.Config.DeliverSubject (although likely set in the processing of the info in switch statement), set shouldCreate to false, so we don't attempt again to add the consumer, then a simple goto . That should take care of validation and recreating the sub/jsi from scratch.
note1: recreate also the ch for sync subscriptions because it has been assigned to another subscription, so you can't reused. This is an issue I found in the past.
note2: you would also have to move the declaration of ccreq *createConsumerRequest and some other at the top of the function).
That's how I do in the C client and find it a bit more clean. That being said, this is with my pull subscribe implementation that uses a single sync subscribe, so basically I have only a single js.nc.subscribe() call, it's just that the deliver subject is an inbox in case of pull subscribe (and a sync flag).
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Code is working, so rather not redo completely again.
Signed-off-by: Derek Collison <[email protected]>
This introduces ordered consumers. They are a convenience over ephemeral, no ack, no redelivery, only deliver things in strict order setups. We have the swap out when we detect gaps and change out the underlying sub and JetStream consumer, and we process the heartbeats as well, detecting gaps at the end or if a stream or consumer is pulled out from underneath of us.
Signed-off-by: Derek Collison [email protected]