[improve][client] Make replicateSubscriptionState nullable

[nodece]

Motivation

The current implementation of subscription replication relies on consumer control with the following configuration:

boolean replicateSubscriptionState = false;
// boolean replicateSubscriptionState = true;
pulsarClient.newConsumer(Schema.STRING)
                .replicateSubscriptionState(replicateSubscriptionState)

By default, the replicateSubscriptionState is set to false in the ConsumerConfigurationData.java, which creates a mismatch with the CommandSubscribe definition, where replicate_subscription_state is optional. To address this, I propose changing the default value of replicateSubscriptionState to null, aligning it with the optional nature of the field in CommandSubscribe.

This adjustment would enhance flexibility in managing subscription replication policies, such as applying the policy that comes from the namespace or topic level, which streamlines the configuration of subscription replication behavior. This feature is in progress.

These changes are compatible with both the old and new versions, there won't be any breaking changes.

Modifications

• The replicateSubscriptionState type is changed from boolean to Boolean and the default value is null in theConsumerConfigurationData.java. When it is null, it won't set the value to the replicate_subscription_state of CommandSubscribe.
• In the broker, use the Boolean instead of boolean to match the replicate_subscription_state of CommandSubscribe.

Documentation

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

[lhotari]

This adjustment would enhance flexibility in managing subscription replication policies, such as applying the policy that comes from the namespace or topic level, which streamlines the configuration of subscription replication behavior. This feature is in progress.

This will be a useful feature.

[lhotari]

This adjustment would enhance flexibility in managing subscription replication policies, such as applying the policy that comes from the namespace or topic level, which streamlines the configuration of subscription replication behavior. This feature is in progress.

This will be a useful feature.

@nodece Please check #23769, it seems to be a related new feature.

[nodece]

@lhotari Sure, go to #23769 and #23770.