在Debian上配置Kafka消费者涉及几个步骤,包括安装Java(Kafka的运行环境)、下载和配置Kafka、以及编写和运行Kafka消费者代码。以下是一个详细的步骤指南:
Kafka需要Java运行环境,因此首先需要安装Java。
sudo apt update
sudo apt install openjdk-11-jdk
验证Java安装:
java -version
从Apache Kafka官方网站下载Kafka。
wget https://downloads.apache.org/kafka/3.3.1/kafka_2.13-3.3.1.tgz
tar -xzf kafka_2.13-3.3.1.tgz
cd kafka_2.13-3.3.1
启动Zookeeper(Kafka的协调服务):
bin/zookeeper-server-start.sh config/zookeeper.properties
在另一个终端启动Kafka服务器:
bin/kafka-server-start.sh config/server.properties
创建一个Kafka主题,消费者将从中读取消息。
bin/kafka-topics.sh --create --topic test-topic --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1
使用Java编写一个简单的Kafka消费者。以下是一个示例代码:
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.Collections;
import java.util.Properties;
public class SimpleConsumer {
public static void main(String[] args) {
Properties props = new Properties();
props.setProperty("bootstrap.servers", "localhost:9092");
props.setProperty("group.id", "test-group");
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<>(props);
consumer.subscribe(Collections.singletonList("test-topic"));
try {
while (true) {
ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
records.forEach(record -> {
System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
});
}
} finally {
consumer.close();
}
}
}
确保你已经安装了Maven或Gradle来管理依赖项。以下是使用Maven的示例:
创建一个pom.xml
文件:
<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.example</groupId>
<artifactId>kafka-consumer</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>3.3.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>11</source>
<target>11</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
在项目目录中运行:
mvn clean package
运行消费者:
java -cp target/kafka-consumer-1.0-SNAPSHOT.jar SimpleConsumer
确保Kafka服务器正在运行,并且主题已经创建。然后运行消费者代码,你应该能够看到从主题中读取的消息。
通过以上步骤,你可以在Debian上成功配置和运行一个Kafka消费者。