Issue-6403: Consumer received duplicated deplayed messages upon restart #6404
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Motivation
Fix when send a delayed message ,there is a case when a consumer restarts and pull duplicate messages. #6403
read entry
Order of reading messages
1、getMessagesToReplayNow
2、asyncReadEntriesOrWait
send consumer
normal situation
1、ReadType.Normal
Because the delay time has not arrived
but filterEntriesForConsumer method will fileter
2、ReadType.Replay
delay time has arrived ,and send consumer
abnormal situation
when the delay time has not arrived, stop conumser,
then the delay time has arrived, start conumser.
1、ReadType.Replay
delay time has arrived ,and send consumer
2、ReadType.Normal
delay time has arrived ,and send consumer
Changes
update readPosition to next