手拉手入门springboot+kafka

安装kafka

启动Kafka本地环境需Java 8+以上

Kafka是一种高吞吐量的分布式发布订阅消息系统，它可以处理消费者在网站中的所有动作流数据。

Kafka启动方式有Zookeeper和Kraft，两种方式只能选择其中一种启动，不能同时使用。

Kafka下载https://downloads.apache.org/kafka/3.7.0/kafka_2.13-3.7.0.tgz

解压tar -xzf kafka_2.13-3.7.0.tgz

一、Zookeeper启动Kafka（kafka内置zookeeper）

Kafka依赖Zookeeper

1、启动Zookeeper 2、启动Kafka

使用kafka自带Zookeeper启动

./zookeeper-server-start.sh ../config/zookeeper.properties &

./zookeeper-server-stop.sh ../config/zookeeper.properties

./kafka-server-start.sh ../config/server.properties &

./kafka-server-stop.sh ../config/server.properties

二、Zookeeper服务器启动Kafka

Zookeeper服务器安装

https://zookeeper.apache.org/

https://dlcdn.apache.org/zookeeper/zookeeper-3.9.2/apache-zookeeper-3.9.2-bin.tar.gz

tar zxvf apache-zookeeper-3.9.2-bin.tar.gz

配置Zookeeper服务器

cp zoo_sample.cfg zoo.cfg

启动Zookeeper服务器

./zkServer.sh start

修改Zookeeper端口

Zoo.cfg添加内容

admin.serverPort=8099

apache-zookeeper-3.9.2-bin/bin目录下重启Zookeeper

Zookeeper服务器启动kafka

/opt/kafka_2.13-3.7.0/bin目录下

./kafka-server-start.sh ../config/server.properties &

Kafka配置文件server.properties

三、使用KRaft启动Kafka

UUID通用唯一识别码（Universally Unique Identifier）

1、生成Cluster UUID(集群UUID)：./kafka-storage.sh random-uuid

2.格式化kafka日志目录：./kafka-storage.sh format -t 3pMJGNJcT0uLIBsZhbucjQ -c ../config/kraft/server.properties

3.启动kafka：./kafka-server-start.sh ../config/kraft/server.properties &

springboot集成kafka

创建topic时，若不指定topic的分区(partition)数量使，则默认为1个分区(partition)

修改server.properties文件

vim server.properties

listeners=PLAINTEXT://0.0.0.0:9092

advertised.listeners=PLAINTEXT://192.168.68.133:9092

springboot加入依赖kafka

<dependency>
<groupId>org.springframework.kafka</groupId>
<artifactId>spring-kafka</artifactId>
</dependency>

加入spring-kafka依赖后，springboot自动装配好kafkaTemplate的Bean

application.yml配置连接kafka

spring:
kafka:
bootstrap-servers: 192.168.68.133:9092

发送消息

@Resource
private KafkaTemplate<String,String> kafkaTemplate;

@Test
void kafkaSendTest(){
kafkaTemplate.send("kafkamsg01","hello kafka");
}

消费者

接收消息

@Component
public class KafkaConsumer {

@KafkaListener(topics = {"kafkamsg01","test"},groupId = "123")
public void consume(String message){
System.out.println("接收到消息："+message);
}

}

若没有配置groupid

Failed to start bean 'org.springframework.kafka.config.internalKafkaListenerEndpointRegistry'; nested exception is java.lang.IllegalStateException: No group.id found in consumer config, container properties, or @KafkaListener annotation; a group.id is required when group management is used.

@Component
public class KafkaConsumer {

@KafkaListener(topics = {"kafkamsg01","test"},groupId = "123")
public void consume(String message){
System.out.println("接收到消息："+message);
}

}