ISSUE-20772: [improve][broker] Add metrics related interfaces for BrokerInterceptor

[streamnativebot]

url: apache#20772

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Motivation

When I want to monitor the relevant data in the BrokerInterceptor, currently the BrokerInterceptor does not provide relevant interfaces.

I think providing such extensions is necessary.

Solution

https://github.com/apache/pulsar/blob/e96b3398912163eb6e0528c10aed3507c95952fd/pulsar-broker/src/main/java/org/apache/pulsar/broker/intercept/BrokerInterceptor.java

Add a interface, like this:

default void addCustomizeMetrics(PrometheusMetricStreams streams, PulsarService pulsar){
}

https://github.com/apache/pulsar/blob/e96b3398912163eb6e0528c10aed3507c95952fd/pulsar-broker/src/main/java/org/apache/pulsar/broker/stats/prometheus/PrometheusMetricsGenerator.java#L185-L187

Then callback the addCustomizeMetrics(stream, pulsar) method here.

This is just a draft.

Alternatives

No response

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!