org.apache.apex.malhar.kafka.EmbeddedKafka.java Source code

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Here is the source code for org.apache.apex.malhar.kafka.EmbeddedKafka.java

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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, 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.apex.malhar.kafka;

import java.io.File;
import java.io.IOException;
import java.net.ServerSocket;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Properties;

import org.I0Itec.zkclient.ZkClient;

import org.apache.commons.io.FileUtils;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

import com.google.common.base.Throwables;

import kafka.admin.AdminUtils;
import kafka.server.KafkaConfig;
import kafka.server.KafkaServer;
import kafka.utils.MockTime;
import kafka.utils.TestUtils;
import kafka.utils.Time;
import kafka.utils.ZKStringSerializer$;
import kafka.utils.ZkUtils;
import kafka.zk.EmbeddedZookeeper;

public class EmbeddedKafka {
    private static final String KAFKA_PATH = "/tmp/kafka-test";

    private ZkClient zkClient;
    private ZkUtils zkUtils;
    private String BROKERHOST = "127.0.0.1";
    private String BROKERPORT = "9092";
    private EmbeddedZookeeper zkServer;
    private KafkaServer kafkaServer;

    public String getBroker() {
        return BROKERHOST + ":" + BROKERPORT;
    }

    public void start() throws IOException {
        // Find port
        try {
            ServerSocket serverSocket = new ServerSocket(0);
            BROKERPORT = Integer.toString(serverSocket.getLocalPort());
            serverSocket.close();
        } catch (IOException e) {
            throw Throwables.propagate(e);
        }

        // Setup Zookeeper
        zkServer = new EmbeddedZookeeper();
        String zkConnect = BROKERHOST + ":" + zkServer.port();
        zkClient = new ZkClient(zkConnect, 30000, 30000, ZKStringSerializer$.MODULE$);
        zkUtils = ZkUtils.apply(zkClient, false);

        // Setup brokers
        cleanupDir();
        Properties props = new Properties();
        props.setProperty("zookeeper.connect", zkConnect);
        props.setProperty("broker.id", "0");
        props.setProperty("log.dirs", KAFKA_PATH);
        props.setProperty("listeners", "PLAINTEXT://" + BROKERHOST + ":" + BROKERPORT);
        KafkaConfig config = new KafkaConfig(props);
        Time mock = new MockTime();
        kafkaServer = TestUtils.createServer(config, mock);
    }

    public void stop() throws IOException {
        kafkaServer.shutdown();
        zkClient.close();
        zkServer.shutdown();
        cleanupDir();
    }

    private void cleanupDir() throws IOException {
        FileUtils.deleteDirectory(new File(KAFKA_PATH));
    }

    public void createTopic(String topic) {
        AdminUtils.createTopic(zkUtils, topic, 1, 1, new Properties());
        List<KafkaServer> servers = new ArrayList<KafkaServer>();
        servers.add(kafkaServer);
        TestUtils.waitUntilMetadataIsPropagated(scala.collection.JavaConversions.asScalaBuffer(servers), topic, 0,
                30000);
    }

    public void publish(String topic, List<String> messages) {
        Properties producerProps = new Properties();
        producerProps.setProperty("bootstrap.servers", BROKERHOST + ":" + BROKERPORT);
        producerProps.setProperty("key.serializer", "org.apache.kafka.common.serialization.IntegerSerializer");
        producerProps.setProperty("value.serializer", "org.apache.kafka.common.serialization.ByteArraySerializer");

        try (KafkaProducer<Integer, byte[]> producer = new KafkaProducer<>(producerProps)) {
            for (String message : messages) {
                ProducerRecord<Integer, byte[]> data = new ProducerRecord<>(topic,
                        message.getBytes(StandardCharsets.UTF_8));
                producer.send(data);
            }
        }

        List<KafkaServer> servers = new ArrayList<KafkaServer>();
        servers.add(kafkaServer);
        TestUtils.waitUntilMetadataIsPropagated(scala.collection.JavaConversions.asScalaBuffer(servers), topic, 0,
                30000);
    }

    public List<String> consume(String topic, int timeout) {
        return consume(topic, timeout, true);
    }

    public List<String> consume(String topic, int timeout, boolean earliest) {
        Properties consumerProps = new Properties();
        consumerProps.setProperty("bootstrap.servers", BROKERHOST + ":" + BROKERPORT);
        consumerProps.setProperty("group.id", "group0");
        consumerProps.setProperty("client.id", "consumer0");
        consumerProps.setProperty("key.deserializer", "org.apache.kafka.common.serialization.IntegerDeserializer");
        consumerProps.setProperty("value.deserializer",
                "org.apache.kafka.common.serialization.ByteArrayDeserializer");
        // to make sure the consumer starts from the beginning of the topic
        consumerProps.put("auto.offset.reset", earliest ? "earliest" : "latest");
        KafkaConsumer<Integer, byte[]> consumer = new KafkaConsumer<>(consumerProps);
        consumer.subscribe(Arrays.asList(topic));

        List<String> messages = new ArrayList<>();

        ConsumerRecords<Integer, byte[]> records = consumer.poll(timeout);
        for (ConsumerRecord<Integer, byte[]> record : records) {
            messages.add(new String(record.value()));
        }

        consumer.close();

        return messages;
    }

}