/*
* 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
*
* 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.streams.kafka;
import org.apache.streams.config.ComponentConfigurator;
import org.apache.streams.config.StreamsConfigurator;
import org.apache.streams.core.StreamsDatum;
import org.apache.streams.core.StreamsPersistReader;
import org.apache.streams.core.StreamsResultSet;
import com.fasterxml.jackson.databind.ObjectMapper;
import kafka.consumer.Consumer;
import kafka.consumer.ConsumerConfig;
import kafka.consumer.KafkaStream;
import kafka.consumer.Whitelist;
import kafka.javaapi.consumer.ConsumerConnector;
import kafka.serializer.StringDecoder;
import kafka.utils.VerifiableProperties;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Serializable;
import java.math.BigInteger;
import java.util.List;
import java.util.Properties;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
/**
* KafkaPersistReader reads documents from kafka.
*/
public class KafkaPersistReader implements StreamsPersistReader, Serializable {
public static final String STREAMS_ID = "KafkaPersistReader";
private static final Logger LOGGER = LoggerFactory.getLogger(KafkaPersistReader.class);
protected volatile Queue<StreamsDatum> persistQueue;
private ObjectMapper mapper = new ObjectMapper();
private KafkaConfiguration config;
private ConsumerConnector consumerConnector;
public List<KafkaStream<String, String>> inStreams;
private ExecutorService executor = Executors.newSingleThreadExecutor();
/**
* KafkaPersistReader constructor - resolves KafkaConfiguration from JVM 'kafka'.
*/
public KafkaPersistReader() {
this.config = new ComponentConfigurator<>(KafkaConfiguration.class)
.detectConfiguration(StreamsConfigurator.getConfig().getConfig("kafka"));
this.persistQueue = new ConcurrentLinkedQueue<>();
}
/**
* KafkaPersistReader constructor - uses supplied persistQueue.
*/
public KafkaPersistReader(Queue<StreamsDatum> persistQueue) {
this.config = new ComponentConfigurator<>(KafkaConfiguration.class)
.detectConfiguration(StreamsConfigurator.getConfig().getConfig("kafka"));
this.persistQueue = persistQueue;
}
public void setConfig(KafkaConfiguration config) {
this.config = config;
}
@Override
public String getId() {
return STREAMS_ID;
}
@Override
public void startStream() {
Properties props = new Properties();
props.setProperty("serializer.encoding", "UTF8");
ConsumerConfig consumerConfig = new ConsumerConfig(props);
consumerConnector = Consumer.createJavaConsumerConnector(consumerConfig);
Whitelist topics = new Whitelist(config.getTopic());
VerifiableProperties vprops = new VerifiableProperties(props);
inStreams = consumerConnector.createMessageStreamsByFilter(topics, 1, new StringDecoder(vprops), new StringDecoder(vprops));
for (final KafkaStream stream : inStreams) {
executor.submit(new KafkaPersistReaderTask(this, stream));
}
}
@Override
public StreamsResultSet readAll() {
return readCurrent();
}
@Override
public StreamsResultSet readCurrent() {
return null;
}
@Override
public StreamsResultSet readNew(BigInteger bigInteger) {
return null;
}
@Override
public StreamsResultSet readRange(DateTime dateTime, DateTime dateTime2) {
return null;
}
@Override
public boolean isRunning() {
return !executor.isShutdown() && !executor.isTerminated();
}
private static ConsumerConfig createConsumerConfig(String zookeeper, String groupId) {
Properties props = new Properties();
props.put("zookeeper.connect", zookeeper);
props.put("group.id", groupId);
props.put("zookeeper.session.timeout.ms", "400");
props.put("zookeeper.sync.time.ms", "200");
props.put("auto.commit.interval.ms", "1000");
return new ConsumerConfig(props);
}
@Override
public void prepare(Object configurationObject) {
}
@Override
public void cleanUp() {
consumerConnector.shutdown();
while ( !executor.isTerminated()) {
try {
executor.awaitTermination(5, TimeUnit.SECONDS);
} catch (InterruptedException interrupt) {
LOGGER.trace("Interrupt", interrupt);
}
}
}
}