org.apache.kafka.common.metrics.MetricsReporter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.kafka.common.metrics;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.kafka.common.Reconfigurable;
import org.apache.kafka.common.annotation.InterfaceStability;
import org.apache.kafka.common.config.ConfigException;
/**
* A plugin interface to allow things to listen as new metrics are created so they can be reported.
*
* Implement {@link org.apache.kafka.common.ClusterResourceListener} to receive cluster metadata once it's available. Please see the class documentation for ClusterResourceListener for more information.
*/
public interface MetricsReporter extends Reconfigurable, AutoCloseable {
/**
* This is called when the reporter is first registered to initially register all existing metrics
* @param metrics All currently existing metrics
*/
void init(List metrics);
/**
* This is called whenever a metric is updated or added
* @param metric
*/
void metricChange(KafkaMetric metric);
/**
* This is called whenever a metric is removed
* @param metric
*/
void metricRemoval(KafkaMetric metric);
/**
* Called when the metrics repository is closed.
*/
void close();
// default methods for backwards compatibility with reporters that only implement Configurable
default Set reconfigurableConfigs() {
return Collections.emptySet();
}
default void validateReconfiguration(Map configs) throws ConfigException {
}
default void reconfigure(Map configs) {
}
/**
* Sets the context labels for the service or library exposing metrics. This will be called before {@link #init(List)} and may be called anytime after that.
*
* @param metricsContext the metric context
*/
@InterfaceStability.Evolving
default void contextChange(MetricsContext metricsContext) {
}
}