hadoop实战-9.kafka的安装与实战

1.准备工具

• zookeeper-3.4.13.tar.gz
• kafka_2.12-2.2.0.tgz

2.安装

tar -zxvf kafka_2.12-2.2.0.tgz
mv kafka_2.12-2.2.0 kafka
cd kafka/config
vim server.properties

broker.id=0      # 每台机器上不一样
listeners=PLAINTEXT://master:9092
log.dirs=/usr/local/kafka/kafka-logs
zookeeper.connect=master:2181,slave1:2181,slave2:2181,slave3:2181

scp -r kafka slave1:/usr/local
vim /etc/profile

export KAFKA_HOME=/usr/local/kafka
export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin:$HIVE_HOME/bin:$ZK_HOME/bin:$HBASE_HOME/bin:$STORM_HOME/bin:$KAFKA_HOME/bin

source /etc/profile

3.启动kafka

集群开启kafka

kafka-server-start.sh /usr/local/kafka/config/server.properties 1>/dev/null 2>&1 &

创建topic test

kafka-topics.sh --create --zookeeper master:2181,slave1:2181,slave2:2181,slave3:2181 --partitions 3 --replication-factor 3 --topic test

创建生产者

kafka-console-producer.sh --broker-list master:9092 --topic test

创建消费者

kafka-console-consumer.sh --bootstrap-server master:9092 --topic test --from-beginning

kafka-tools 工具查看
kafka-tools：http://www.kafkatool.com/download.html

kafka.png

4.kafka java代码

ProducerDemo.java

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

import java.util.Properties;

public class ProducerDemo {

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

        Properties props = new Properties();
        props.put("bootstrap.servers", "master:9092, slave1:9092, slave2:9092, slave3:9092");
        props.put("acks", "all");               // 记录完整提交，最慢的但是最大可能的持久化
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        Producer<String, String> producer = new KafkaProducer<String, String>(props);
        for (int i = 0; i < 100; i++) {
            Thread.sleep(500);
            producer.send(new ProducerRecord<String, String>("my-replicated-topic",
                    Integer.toString(i), "I love you kafka " + i + " times!"));
        }
        producer.close();
    }

}

ConsumerDemo.java

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;

import java.time.Duration;
import java.util.Arrays;
import java.util.Properties;

public class ConsumerDemo {

    public static void main(String[] args) throws Exception{
        Properties props = new Properties();
        props.put("bootstrap.servers", "master:9092, slave1:9092, slave2:9092, slave3:9092");
        props.setProperty("group.id", "my-replicated-topic");
        props.setProperty("enable.auto.commit", "true");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        KafkaConsumer<String, String> consumer = new KafkaConsumer<String, String>(props);
        consumer.subscribe(Arrays.asList("my-replicated-topic"));
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
            for (ConsumerRecord<String, String> record : records)
                System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
        }
    }
}

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.ctgu</groupId>
    <artifactId>kafka_test</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients -->
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.2.0</version>
        </dependency>

    </dependencies>

</project>