ZeroQueueConsumer is not supported with RetryEnable

[crossoverJie]

(If this PR fixes a github issue, please add Fixes #<xyz>.)

Fixes #1319

Modifications

https://github.com/apache/pulsar/blob/89167308709cf72d3f2731bad1bb30384f80abb4/pulsar-client/src/main/java/org/apache/pulsar/client/impl/MultiTopicsConsumerImpl.java#L148-L149

We need to be consistent with the Java Client; ZeroQueueConsumer does not support use with RetryEnable.

Verifying this change

• Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change is a trivial rework / code cleanup without any test coverage.

(or)

This change is already covered by existing tests, such as (please describe tests).

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This change added tests and can be verified as follows:

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): (no)
• The public API: (no)
• The schema: (no)
• The default values of configurations: (no)
• The wire protocol: (no)

Documentation

• Does this pull request introduce a new feature? (no)
• If yes, how is the feature documented? (not applicable / docs / GoDocs / not documented)
• If a feature is not applicable for documentation, explain why?
• If a feature is not documented yet in this PR, please create a followup issue for adding the documentation

[BewareMyPower]

https://github.com/apache/pulsar/blob/89167308709cf72d3f2731bad1bb30384f80abb4/pulsar-client/src/main/java/org/apache/pulsar/client/impl/MultiTopicsConsumerImpl.java#L148-L149

        checkArgument(conf.getReceiverQueueSize() > 0,
            "Receiver queue size needs to be greater than 0 for Topics Consumer");

This assertion disallows the receiver queue size as 0 for a multi-topics consumer. It seems not related to this PR?

[crossoverJie]

apache/pulsar@8916730/pulsar-client/src/main/java/org/apache/pulsar/client/impl/MultiTopicsConsumerImpl.java#L148-L149

        checkArgument(conf.getReceiverQueueSize() > 0,
            "Receiver queue size needs to be greater than 0 for Topics Consumer");

This assertion disallows the receiver queue size as 0 for a multi-topics consumer. It seems not related to this PR?

In the Java client, setting receiverQueueSize to 0 will create a ZeroQueueConsumer; additionally, if RetryEnable is enabled, a MultiTopicsConsumer will be created. therefore, it is necessary to check the size of receiverQueueSize in MultiTopicsConsumer.

In the Go client, if RetryEnable is enabled in ZeroQueueConsumer, a MultiTopicConsumer will also be created. In this case, ReceiverQueueSize being equal to 0 will result in message data not being received.

The only difference from the Java Client is that the validation conditions are moved forward to the consumer creation stage.

[Copilot]

Pull Request Overview

This PR adds validation to prevent the incompatible combination of RetryEnable and EnableZeroQueueConsumer options, maintaining consistency with the Java Pulsar client implementation.

• Adds early validation in the consumer constructor to reject incompatible configuration
• Includes test coverage to verify the validation works correctly

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
pulsar/consumer_impl.go	Adds validation logic to reject RetryEnable + EnableZeroQueueConsumer combination
pulsar/consumer_zero_queue_test.go	Adds test case to verify the validation error is properly returned

Comments suppressed due to low confidence (1)