org.apache.streams.amazon.kinesis.KinesisPersistReader.java Source code

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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
 *
 *   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.amazon.kinesis;

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.amazonaws.ClientConfiguration;
import com.amazonaws.Protocol;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.kinesis.AmazonKinesisClient;
import com.amazonaws.services.kinesis.model.DescribeStreamResult;
import com.amazonaws.services.kinesis.model.Shard;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.typesafe.config.Config;
import org.apache.commons.lang3.StringUtils;
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.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

/**
 * KinesisPersistReader reads documents from kinesis.
 */
public class KinesisPersistReader implements StreamsPersistReader, Serializable {

    public static final String STREAMS_ID = "KinesisPersistReader";

    private static final Logger LOGGER = LoggerFactory.getLogger(KinesisPersistReader.class);

    protected volatile Queue<StreamsDatum> persistQueue;

    private ObjectMapper mapper = new ObjectMapper();

    private KinesisReaderConfiguration config;

    protected Long pollInterval = StreamsConfigurator.detectConfiguration().getBatchFrequencyMs();

    private List<String> streamNames;

    private ExecutorService executor;

    protected AmazonKinesisClient client;

    /**
     * KinesisPersistReader constructor - resolves KinesisReaderConfiguration from JVM 'kinesis'.
     */
    public KinesisPersistReader() {
        Config config = StreamsConfigurator.config.getConfig("kinesis");
        this.config = new ComponentConfigurator<>(KinesisReaderConfiguration.class).detectConfiguration(config);
        this.persistQueue = new ConcurrentLinkedQueue<>();
    }

    /**
     * KinesisPersistReader constructor - uses provided KinesisReaderConfiguration.
     */
    public KinesisPersistReader(KinesisReaderConfiguration config) {
        this.config = config;
        this.persistQueue = new ConcurrentLinkedQueue<>();
    }

    public void setConfig(KinesisReaderConfiguration config) {
        this.config = config;
    }

    @Override
    public String getId() {
        return STREAMS_ID;
    }

    @Override
    public void startStream() {

        this.streamNames = this.config.getStreams();

        for (final String stream : streamNames) {

            DescribeStreamResult describeStreamResult = client.describeStream(stream);

            if ("ACTIVE".equals(describeStreamResult.getStreamDescription().getStreamStatus())) {

                List<Shard> shardList = describeStreamResult.getStreamDescription().getShards();

                for (Shard shard : shardList) {
                    executor.submit(new KinesisPersistReaderTask(this, stream, shard.getShardId()));
                }
            }

        }

    }

    @Override
    public StreamsResultSet readAll() {
        return readCurrent();
    }

    public StreamsResultSet readCurrent() {

        StreamsResultSet current;
        synchronized (KinesisPersistReader.class) {
            current = new StreamsResultSet(new ConcurrentLinkedQueue<>(persistQueue));
            persistQueue.clear();
        }
        return current;
    }

    @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();
    }

    @Override
    public void prepare(Object configurationObject) {
        // Connect to Kinesis
        synchronized (this) {
            // Create the credentials Object
            AWSCredentials credentials = new BasicAWSCredentials(config.getKey(), config.getSecretKey());

            ClientConfiguration clientConfig = new ClientConfiguration();
            clientConfig.setProtocol(Protocol.valueOf(config.getProtocol().toString()));

            this.client = new AmazonKinesisClient(credentials, clientConfig);
            if (StringUtils.isNotEmpty(config.getRegion()))
                this.client.setRegion(Region.getRegion(Regions.fromName(config.getRegion())));
        }
        streamNames = this.config.getStreams();
        executor = Executors.newFixedThreadPool(streamNames.size());
    }

    @Override
    public void cleanUp() {

        while (!executor.isTerminated()) {
            try {
                executor.awaitTermination(5, TimeUnit.SECONDS);
            } catch (InterruptedException ignored) {
            }
        }
    }
}