org.apache.kafka.clients.consumer.internals.ConsumerInterceptors Maven / Gradle / Ivy
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* 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,
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.kafka.clients.consumer.internals;
import org.apache.kafka.clients.consumer.ConsumerInterceptor;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.OffsetAndMetadata;
import org.apache.kafka.common.TopicPartition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Closeable;
import java.util.List;
import java.util.Map;
/**
* A container that holds the list {@link org.apache.kafka.clients.consumer.ConsumerInterceptor}
* and wraps calls to the chain of custom interceptors.
*/
public class ConsumerInterceptors implements Closeable {
private static final Logger log = LoggerFactory.getLogger(ConsumerInterceptors.class);
private final List> interceptors;
public ConsumerInterceptors(List> interceptors) {
this.interceptors = interceptors;
}
/**
* This is called when the records are about to be returned to the user.
*
* This method calls {@link ConsumerInterceptor#onConsume(ConsumerRecords)} for each
* interceptor. Records returned from each interceptor get passed to onConsume() of the next interceptor
* in the chain of interceptors.
*
* This method does not throw exceptions. If any of the interceptors in the chain throws an exception,
* it gets caught and logged, and next interceptor in the chain is called with 'records' returned by the
* previous successful interceptor onConsume call.
*
* @param records records to be consumed by the client.
* @return records that are either modified by interceptors or same as records passed to this method.
*/
public ConsumerRecords onConsume(ConsumerRecords records) {
ConsumerRecords interceptRecords = records;
for (ConsumerInterceptor interceptor : this.interceptors) {
try {
interceptRecords = interceptor.onConsume(interceptRecords);
} catch (Exception e) {
// do not propagate interceptor exception, log and continue calling other interceptors
log.warn("Error executing interceptor onConsume callback", e);
}
}
return interceptRecords;
}
/**
* This is called when commit request returns successfully from the broker.
*
* This method calls {@link ConsumerInterceptor#onCommit(Map)} method for each interceptor.
*
* This method does not throw exceptions. Exceptions thrown by any of the interceptors in the chain are logged, but not propagated.
*
* @param offsets A map of offsets by partition with associated metadata
*/
public void onCommit(Map offsets) {
for (ConsumerInterceptor interceptor : this.interceptors) {
try {
interceptor.onCommit(offsets);
} catch (Exception e) {
// do not propagate interceptor exception, just log
log.warn("Error executing interceptor onCommit callback", e);
}
}
}
/**
* Closes every interceptor in a container.
*/
@Override
public void close() {
for (ConsumerInterceptor interceptor : this.interceptors) {
try {
interceptor.close();
} catch (Exception e) {
log.error("Failed to close consumer interceptor ", e);
}
}
}
}