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package org.apache.kafka.common;

import org.apache.kafka.common.metrics.Metrics;

/**
 * Interface for plugins to get Metrics instance
 */
public interface Monitorable {
    /**
     * Get the instance of {@link Metrics}.
     */
    default void monitor(Metrics metrics) {
		return;
	};
}

org.apache.kafka.server.authorizer.Authorizer Metrics need be updated to extends Monitorable Interface.
org.apache.kafka.server.authorizer.Authorizer

The following metrics would be added:

Metrics group name: "kafka.security.authorizer.metrics"
Metric "acls-total-count" for reporting total acls created.
Metric "authorization-request-rate-per-minute" for reporting total number of authorization requests per minute
Metric "authorization-allowed-rate-per-minute" for reporting total number of authorization allowed per minute
Metric "authorization-denied-rate-per-minute" for reporting total number of authorization denied per minute    

Proposed Changes

org.apache.kafka.server.authorizer.Authorizer Metrics need be updated to extends Monitorable Interface.

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kafka.server.KafkaServer will be updated to pass instance of Metrics to Authorizer.

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