kafka写入hdfs

碰到的问题

　　（1）线程操作问题，因为单机节点，代码加锁就好了，后续再写

　　（2） 消费者写hdfs的时候以流的形式写入，但是什么时候关闭流就是一个大问题了，这里引入了   fsDataOutputStream.hsync();

hsync  保证 hdfs在写数据的时候被新的reader读到，保证数据被datanode持久化

生产者

package com.xuliugen.kafka.demo;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

import java.util.Properties;

public class ProducerDemo {

    // Topic
    private static final String topic = "tangsonghuai";

    public static void main(String[] args) throws Exception {

        Properties props = new Properties();
        props.put("bootstrap.servers", "192.168.15.140:9092");
        props.put("acks", "0");
        props.put("group.id", "1111");
        props.put("retries", "0");
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

        //生产者实例
        KafkaProducer producer = new KafkaProducer(props);

        int i = 1;

        // 发送业务消息
        // 读取文件 读取内存数据库 读socket端口
        while (i<50) {
            Thread.sleep(100);
            producer.send(new ProducerRecord<String, String>(topic, "key:" + i, "value:" + i));
            System.out.println("key:" + i + " " + "value:" + i);
            i++;
        }
    }
}

消费者

package com.xuliugen.kafka.demo;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.net.URI;
import java.util.*;

public class ConsumerDemo {
    private static final Logger logger = LoggerFactory.getLogger(ConsumerDemo.class);
    private static final String topic = "tangsonghuai";

    public static void main(String[] args) throws IOException {

        Properties props = new Properties();
        props.put("bootstrap.servers", "192.168.15.140:9092");
        props.put("group.id", "1111");
        props.put("enable.auto.commit", "true");
        props.put("auto.commit.interval.ms", "1000");
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer<String, String>(props);

        consumer.subscribe(Arrays.asList(topic));
        int i = 0;
        String uri = "hdfs://192.168.15.140:9000/";
        Configuration configuration = new Configuration();
        configuration.set("dfs.client.block.write.replace-datanode-on-failure.policy", "NEVER");

        FileSystem fs = FileSystem.get(URI.create(uri), configuration);
        final String pathString = "/d1/tangsonghuai";
        final FSDataOutputStream fsDataOutputStream = fs.append(new Path(pathString));
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(1000);
            for (ConsumerRecord<String, String> record : records) {
                System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
//                HashMap<String, String> hmap= new HashMap<String, String>();
//                hmap.put(record.key(),record.value());


                fsDataOutputStream.write((record.offset()+","+record.key() + "," + record.value()+"
").getBytes());
                fsDataOutputStream.hsync();
                i++;
                if (i == 70) {
                    fsDataOutputStream.close();
                    consumer.close();
                }

//                IOUtils.copyBytes(new ByteArrayInputStream(record.value().getBytes()),
//                        fsDataOutputStream,configuration, true);
            }
        }


    }
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.xuliugen.kafka</groupId>
    <artifactId>kafka.demo</artifactId>
    <version>1.0-SNAPSHOT</version>


    <dependencies>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.0.0</version>
        </dependency>

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.12</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.12</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.hadoop/hadoop-common -->
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-common</artifactId>
            <version>2.8.5</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.hadoop/hadoop-hdfs -->
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-hdfs</artifactId>
            <version>2.8.5</version>
        </dependency>


    </dependencies>

</project>