[broker] Consumer is registered on dispatcher even if hash range conflicts on Key_Shared subscription - #7444
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…Key_Shared subscription
merlimat
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codelipenghui
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…Key_Shared subscription (apache#7444) (cherry picked from commit 97ee82e)
huangdx0726
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…Key_Shared subscription (apache#7444)
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Motivation
If hash ranges specified by multiple consumers conflict on a Key_Shared subscription, the consumer that connects later will fail to subscribe. When this happens, the consumer that should have failed to subscribe is added to the topic stats. These "non-existent" consumers will not disappear until the broker server is restarted.
When the hash ranges conflict, an exception is thrown from
HashRangeExclusiveStickyKeyConsumerSelector#addConsumer(). However, at that time, the addition of the consumer toconsumerListandconsumerSetof the dispatcher has already been completed, and it will not be removed.pulsar/pulsar-broker/src/main/java/org/apache/pulsar/broker/service/persistent/PersistentStickyKeyDispatcherMultipleConsumers.java
Lines 94 to 96 in 1bdfc0d
Modifications
If an exception is thrown from
HashRangeExclusiveStickyKeyConsumerSelector#addConsumer(), remove the consumer added toconsumerListandconsumerSet.