[fix][broker]Fixed an issue where sending chunk messages would be lost when no consumers were online

[zjxxzjwang]

Motivation

When no consumers are online for a subscription, sending chunked messages will be lost.

Modifications

When no subscribers are online, send chunk messages to deliver them to the redeliveryMessages queue. When a subscriber comes online, it can consume the messages again.

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

[github-actions]

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[lhotari]

Thanks for the PR @zjxxzjwang . Please add a test that demonstrates the broken behavior and shows that the changes in this PR fix the problem.

[Copilot]

Pull request overview

This PR fixes an issue where chunked messages would be lost when no consumers are online for a subscription. The fix ensures that when no consumer is available to receive messages, the messages are sent to the redelivery queue instead of being released, allowing them to be consumed when consumers come back online.

Key Changes

• Modified SharedConsumerAssignor to accept a Subscription parameter for logging and to process unassigned messages instead of releasing them
• Updated both PersistentDispatcherMultipleConsumers and PersistentDispatcherMultipleConsumersClassic to pass the subscription to the assignor
• Added logging when no consumer is found to assign messages

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
pulsar-broker/src/main/java/org/apache/pulsar/broker/service/SharedConsumerAssignor.java	Core fix: Added subscription parameter, logging, and changed to use unassignedMessageProcessor instead of releasing entries when no consumers are available
pulsar-broker/src/main/java/org/apache/pulsar/broker/service/persistent/PersistentDispatcherMultipleConsumers.java	Updated SharedConsumerAssignor constructor call to pass subscription parameter
pulsar-broker/src/main/java/org/apache/pulsar/broker/service/persistent/PersistentDispatcherMultipleConsumersClassic.java	Updated SharedConsumerAssignor constructor call to pass subscription parameter
pulsar-broker/src/test/java/org/apache/pulsar/broker/service/SharedConsumerAssignorTest.java	Updated test to pass null for subscription parameter in constructor

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[zjxxzjwang]

Thanks for the PR @zjxxzjwang . Please add a test that demonstrates the broken behavior and shows that the changes in this PR fix the problem.

@lhotari Okay, I will make additional comments

[zjxxzjwang]

@lhotari I have submitted the test cases, please review them

[zjxxzjwang]

@lhotari Hello, please review it