springboot整合kafka--从0到1(技术篇)

Kafka 是由 Apache 软件基金会开发的一个开源流处理平台，由 Scala 和 Java 编写。 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。本章介绍 Spring Boot 集成 Kafka 收发消息。

Spring 有专门的项目支持 Kafka ，引入依赖包时需要注意版本兼容问题，以下是 Spring for Apache Kafka 版本兼容列表：

 

一.安装JAVA JDK

1、下载安装包

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

注意：根据32/64位操作系统下载对应的安装包

2、添加系统变量：JAVA_HOME=C:\Program Files (x86)\Java\jdk1.8.0_144

二.安装zookeeper

1、 下载安装包

http://zookeeper.apache.org/releases.html#download

2、 解压并进入ZooKeeper目录，进入目录中的conf文件夹

3、 将“zoo_sample.cfg”重命名为“zoo.cfg”

4、 打开“zoo.cfg”找到并编辑dataDir=D:\Kafka\zookeeper-3.4.9\tmp(必须以\分割)

5、 添加系统变量：ZOOKEEPER_HOME=D:\Kafka\zookeeper-3.4.9

6、 编辑path系统变量，添加路径：%ZOOKEEPER_HOME%\bin

7、 在zoo.cfg文件中修改默认的Zookeeper端口（默认端口2181）

8、 打开新的cmd，输入“zkServer“，运行Zookeeper

9、 命令行提示如下：说明本地Zookeeper启动成功

 

注意：不要关了这个窗口

当然你如果不确定有没有启动成功

在命令行中使用netstat -ano | findstr 2181（zookeeper默认是2181端口）

 

三.安装Kafka

1、 下载安装包

http://kafka.apache.org/downloads

注意要下载二进制版本

 

2、 解压并进入Kafka目录，笔者：D:\Kafka\kafka_2.12-0.11.0.0

3、 进入config目录找到文件server.properties并打开

4、 找到并编辑log.dirs=D:\Kafka\kafka_2.12-0.11.0.0\kafka-logs

5、 找到并编辑zookeeper.connect=localhost:2181

6、 Kafka会按照默认，在9092端口上运行，并连接zookeeper的默认端口：2181

7、 进入Kafka安装目录D:\Kafka\kafka_2.12-0.11.0.0，按下Shift+右键，选择“打开命令窗口”选项，打开命令行，输入：
 

注意：注意：不要关了这个窗口，启用Kafka前请确保ZooKeeper实例已经准备好并开始运行

四.springboot集成kafka

1.在pom文件中引入依赖（具体的版本号建议通过spring-boot-dependencies管理）

    org.springframework.kafka
    spring-kafka

指定 Scala 版本解决 Jackson/Scala 兼容问题：

   org.scala-lang
   scala-library
   {version}
   test



   org.scala-lang
   scala-reflect
   {version}
   test

2.配置application.yml文件

spring:
  application:
    name: demo

  kafka:
    # kafka连接接地址
    bootstrap-servers: ${KAFKA_HOST:localhost}:${KAFKA_PORT:9092} # kafka连接接地址
    # 生产者配置
    producer: 
      retries: 0 # 重试次数
      acks: 1 # 应答级别:多少个分区副本备份完成时向生产者发送ack确认(可选0、1、all/-1)
      batch-size: 16384 # 批量大小
      buffer-memory: 33554432 # 生产端缓冲区大小
      # 序列化key的类
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      # 序列化value的类
      value-serializer: org.apache.kafka.common.serialization.StringSerializer

    # 消费者配置
    consumer: 
      group-id: javagroup # 默认的消费组ID
      enable-auto-commit: true # 是否自动提交offset
      auto-commit-interval: 100  # 提交offset延时(接收到消息后多久提交offset)

      # earliest:当各分区下有已提交的offset时，从提交的offset开始消费；无提交的offset时，从头开始消费
      # latest:当各分区下有已提交的offset时，从提交的offset开始消费；无提交的offset时，消费新产生的该分区下的数据
      # none:topic各分区都存在已提交的offset时，从offset后开始消费；只要有一个分区不存在已提交的offset，则抛出异常
      auto-offset-reset: latest
      # 序列化key的类
      key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
      # 序列化value的类
      value-deserializer: org.apache.kafka.common.serialization.StringDeserializer

详解：

通用配置：spring.kafka.*
admin、producer、consumer、streams配置会覆盖通用配置 spring.kafka.* 中相同的属性

生产者相关配置：spring.kafka.producer.*

消费者相关配置：spring.kafka.consumer.*

默认 value-serializer 使用 org.apache.kafka.common.serialization.StringDeserializer ，只支持文本消息。自定义 org.springframework.kafka.support.serializer.JsonDeserializer 可以让消息支持其他类型。

3.主启动类

新建KafkaMQApplication.java启动类，
注意要新增 @EnableKafka 注解:

package com.yuwen.spring.kafka;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.kafka.annotation.EnableKafka;

@SpringBootApplication
@EnableKafka
public class KafkaMQApplication {
    public static void main(String[] args) {
        SpringApplication.run(KafkaMQApplication.class, args);
    }
}

4.生产者发送消息：

Spring Kafka 提供KafkaTemplate类发送消息，
在需要的地方注入即可，
新增ProviderService.java生产者服务类：

package com.yuwen.spring.kafka.provider;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Service;

@Service
public class ProviderService {
    public static final String TOPIC = "testTopic";

    @Autowired
    private KafkaTemplate kafkaTemplate;

    public void send(String message) {
        // 发送消息
        kafkaTemplate.send(TOPIC, message);
        System.out.println("Provider= " + message);
    }
}

注意指定 topic ，以及要发送的消息内容message。

5.消费者接收消息：

新增ConsumerService.java类，
注意使用 @KafkaListener 注解：

package com.yuwen.spring.kafka.consumer;

import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

import com.yuwen.spring.kafka.provider.ProviderService;

@Service
public class ConsumerService {
    @KafkaListener(topics = ProviderService.TOPIC, groupId = "testGroup", topicPartitions = {})
    public void receive(String message) {
        System.out.println("Consumer= " + message);
    }
}

参数说明：
topics 与发送消息topic相同，可以指定多个
groupId 消费组唯一id
topicPartitions topic分区，可指定多个

6.自动产生消息

为了测试生产者产生消息，
编写AutoGenerate.java

在项目启动时候，自动生成随机字符串，
作为生产者向kafka发送消息：

package com.yuwen.spring.kafka.provider;

import java.util.UUID;
import java.util.concurrent.TimeUnit;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component
public class AutoGenerate implements InitializingBean {

    @Autowired
    private ProviderService providerService;

    @Override
    public void afterPropertiesSet() throws Exception {
        Thread t = new Thread(new Runnable() {

            @Override
            public void run() {
                while (true) {
                    String message = UUID.randomUUID().toString();
                    providerService.send(message);
                    try {
                        TimeUnit.SECONDS.sleep(1);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        });

        t.start();
    }
}

7.启动项目

运行KafkaMQApplication.java启动类，
输出如下日志,
可以看到生产者产生的随机字符串，
能够被消费者正确获取到：

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.3.1.RELEASE)

2022-04-28 19:37:49.687  INFO 14424 --- [           main] c.yuwen.spring.kafka.KafkaMQApplication  : Starting KafkaMQApplication on yuwen-asiainfo with PID 14424 (D:\Code\Learn\SpringBoot\spring-boot-demo\MessageQueue\kafka\target\classes started by yuwen in D:\Code\Learn\SpringBoot\spring-boot-demo\MessageQueue\kafka)
2022-04-28 19:37:49.689  INFO 14424 --- [           main] c.yuwen.spring.kafka.KafkaMQApplication  : No active profile set, falling back to default profiles: default
2022-04-28 19:37:51.282  INFO 14424 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8028 (http)
2022-04-28 19:37:51.290  INFO 14424 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2022-04-28 19:37:51.291  INFO 14424 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.36]
2022-04-28 19:37:51.371  INFO 14424 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2022-04-28 19:37:51.371  INFO 14424 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1645 ms
2022-04-28 19:37:51.491  INFO 14424 --- [     Thread-119] o.a.k.clients.producer.ProducerConfig    : ProducerConfig values: 
    acks = 1
    batch.size = 16384
    bootstrap.servers = [10.21.13.14:9092]
    buffer.memory = 33554432
    client.dns.lookup = default
    client.id = producer-1
    compression.type = none
    connections.max.idle.ms = 540000
    delivery.timeout.ms = 120000
    enable.idempotence = false
    interceptor.classes = []
    key.serializer = class org.apache.kafka.common.serialization.StringSerializer
    linger.ms = 0
    max.block.ms = 60000
    max.in.flight.requests.per.connection = 5
    max.request.size = 1048576
    metadata.max.age.ms = 300000
    metadata.max.idle.ms = 300000
    metric.reporters = []
    metrics.num.samples = 2
    metrics.recording.level = INFO
    metrics.sample.window.ms = 30000
    partitioner.class = class org.apache.kafka.clients.producer.internals.DefaultPartitioner
    receive.buffer.bytes = 32768
    reconnect.backoff.max.ms = 1000
    reconnect.backoff.ms = 50
    request.timeout.ms = 30000
    retries = 2147483647
    retry.backoff.ms = 100
    sasl.client.callback.handler.class = null
    sasl.jaas.config = null
    sasl.kerberos.kinit.cmd = /usr/bin/kinit
    sasl.kerberos.min.time.before.relogin = 60000
    sasl.kerberos.service.name = null
    sasl.kerberos.ticket.renew.jitter = 0.05
    sasl.kerberos.ticket.renew.window.factor = 0.8
    sasl.login.callback.handler.class = null
    sasl.login.class = null
    sasl.login.refresh.buffer.seconds = 300
    sasl.login.refresh.min.period.seconds = 60
    sasl.login.refresh.window.factor = 0.8
    sasl.login.refresh.window.jitter = 0.05
    sasl.mechanism = GSSAPI
    security.protocol = PLAINTEXT
    security.providers = null
    send.buffer.bytes = 131072
    ssl.cipher.suites = null
    ssl.enabled.protocols = [TLSv1.2]
    ssl.endpoint.identification.algorithm = https
    ssl.key.password = null
    ssl.keymanager.algorithm = SunX509
    ssl.keystore.location = null
    ssl.keystore.password = null
    ssl.keystore.type = JKS
    ssl.protocol = TLSv1.2
    ssl.provider = null
    ssl.secure.random.implementation = null
    ssl.trustmanager.algorithm = PKIX
    ssl.truststore.location = null
    ssl.truststore.password = null
    ssl.truststore.type = JKS
    transaction.timeout.ms = 60000
    transactional.id = null
    value.serializer = class org.springframework.kafka.support.serializer.JsonSerializer

2022-04-28 19:37:51.563  INFO 14424 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2022-04-28 19:37:51.590  INFO 14424 --- [     Thread-119] o.a.kafka.common.utils.AppInfoParser     : Kafka version: 2.5.0
2022-04-28 19:37:51.592  INFO 14424 --- [     Thread-119] o.a.kafka.common.utils.AppInfoParser     : Kafka commitId: 66563e712b0b9f84
2022-04-28 19:37:51.592  INFO 14424 --- [     Thread-119] o.a.kafka.common.utils.AppInfoParser     : Kafka startTimeMs: 1651145871589
2022-04-28 19:37:51.851  INFO 14424 --- [           main] o.a.k.clients.consumer.ConsumerConfig    : ConsumerConfig values: 
    allow.auto.create.topics = true
    auto.commit.interval.ms = 5000
    auto.offset.reset = latest
    bootstrap.servers = [10.21.13.14:9092]
    check.crcs = true
    client.dns.lookup = default
    client.id = 
    client.rack = 
    connections.max.idle.ms = 540000
    default.api.timeout.ms = 60000
    enable.auto.commit = false
    exclude.internal.topics = true
    fetch.max.bytes = 52428800
    fetch.max.wait.ms = 500
    fetch.min.bytes = 1
    group.id = testGroup
    group.instance.id = null
    heartbeat.interval.ms = 3000
    interceptor.classes = []
    internal.leave.group.on.close = true
    isolation.level = read_uncommitted
    key.deserializer = class org.apache.kafka.common.serialization.StringDeserializer
    max.partition.fetch.bytes = 1048576
    max.poll.interval.ms = 300000
    max.poll.records = 500
    metadata.max.age.ms = 300000
    metric.reporters = []
    metrics.num.samples = 2
    metrics.recording.level = INFO
    metrics.sample.window.ms = 30000
    partition.assignment.strategy = [class org.apache.kafka.clients.consumer.RangeAssignor]
    receive.buffer.bytes = 65536
    reconnect.backoff.max.ms = 1000
    reconnect.backoff.ms = 50
    request.timeout.ms = 30000
    retry.backoff.ms = 100
    sasl.client.callback.handler.class = null
    sasl.jaas.config = null
    sasl.kerberos.kinit.cmd = /usr/bin/kinit
    sasl.kerberos.min.time.before.relogin = 60000
    sasl.kerberos.service.name = null
    sasl.kerberos.ticket.renew.jitter = 0.05
    sasl.kerberos.ticket.renew.window.factor = 0.8
    sasl.login.callback.handler.class = null
    sasl.login.class = null
    sasl.login.refresh.buffer.seconds = 300
    sasl.login.refresh.min.period.seconds = 60
    sasl.login.refresh.window.factor = 0.8
    sasl.login.refresh.window.jitter = 0.05
    sasl.mechanism = GSSAPI
    security.protocol = PLAINTEXT
    security.providers = null
    send.buffer.bytes = 131072
    session.timeout.ms = 10000
    ssl.cipher.suites = null
    ssl.enabled.protocols = [TLSv1.2]
    ssl.endpoint.identification.algorithm = https
    ssl.key.password = null
    ssl.keymanager.algorithm = SunX509
    ssl.keystore.location = null
    ssl.keystore.password = null
    ssl.keystore.type = JKS
    ssl.protocol = TLSv1.2
    ssl.provider = null
    ssl.secure.random.implementation = null
    ssl.trustmanager.algorithm = PKIX
    ssl.truststore.location = null
    ssl.truststore.password = null
    ssl.truststore.type = JKS
    value.deserializer = class org.springframework.kafka.support.serializer.JsonDeserializer

2022-04-28 19:37:51.888  INFO 14424 --- [           main] o.a.kafka.common.utils.AppInfoParser     : Kafka version: 2.5.0
2022-04-28 19:37:51.888  INFO 14424 --- [           main] o.a.kafka.common.utils.AppInfoParser     : Kafka commitId: 66563e712b0b9f84
2022-04-28 19:37:51.888  INFO 14424 --- [           main] o.a.kafka.common.utils.AppInfoParser     : Kafka startTimeMs: 1651145871888
2022-04-28 19:37:51.890  INFO 14424 --- [           main] o.a.k.clients.consumer.KafkaConsumer     : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Subscribed to topic(s): testTopic
2022-04-28 19:37:51.892  INFO 14424 --- [           main] o.s.s.c.ThreadPoolTaskScheduler          : Initializing ExecutorService
2022-04-28 19:37:51.911  INFO 14424 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8028 (http) with context path ''
2022-04-28 19:37:51.921  INFO 14424 --- [           main] c.yuwen.spring.kafka.KafkaMQApplication  : Started KafkaMQApplication in 2.582 seconds (JVM running for 2.957)
2022-04-28 19:37:51.939  INFO 14424 --- [ntainer#0-0-C-1] org.apache.kafka.clients.Metadata        : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Cluster ID: zdSPCGGvT8qBnM4LSjz9Hw
2022-04-28 19:37:51.939  INFO 14424 --- [ad | producer-1] org.apache.kafka.clients.Metadata        : [Producer clientId=producer-1] Cluster ID: zdSPCGGvT8qBnM4LSjz9Hw
2022-04-28 19:37:51.940  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.AbstractCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Discovered group coordinator 10.21.13.14:9092 (id: 2147483647 rack: null)
2022-04-28 19:37:51.942  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.AbstractCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] (Re-)joining group
2022-04-28 19:37:51.959  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.ConsumerCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Finished assignment for group at generation 5: {consumer-testGroup-1-35e34543-5bf3-4a4a-a590-9a4c6f7e1ae3=Assignment(partitions=[testTopic-0])}
Provider= c30a2e6c-e2e8-419e-865c-04885d1a90b5
2022-04-28 19:37:51.966  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.AbstractCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Successfully joined group with generation 5
2022-04-28 19:37:51.970  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.ConsumerCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Adding newly assigned partitions: testTopic-0
2022-04-28 19:37:51.984  INFO 14424 --- [ntainer#0-0-C-1] o.a.k.c.c.internals.ConsumerCoordinator  : [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Setting offset for partition testTopic-0 to the committed offset FetchPosition{offset=310751, offsetEpoch=Optional.empty, currentLeader=LeaderAndEpoch{leader=Optional[10.21.13.14:9092 (id: 0 rack: null)], epoch=absent}}
2022-04-28 19:37:51.985  INFO 14424 --- [ntainer#0-0-C-1] o.s.k.l.KafkaMessageListenerContainer    : testGroup: partitions assigned: [testTopic-0]
Consumer= 19210493-d0df-4cd9-993b-f99500523eb2
Consumer= baee3749-307f-4894-ad88-a9610700ab80
Consumer= bea5e807-b003-4c90-89be-20439e2fa921
Consumer= 98258208-8a95-495d-917e-84d30d965e2b
Consumer= 4301851e-ab19-4c9e-89d6-7b604acdf077
Consumer= c30a2e6c-e2e8-419e-865c-04885d1a90b5
Provider= a6d47e9e-de74-481f-82f8-02bd7384fdd8
Consumer= a6d47e9e-de74-481f-82f8-02bd7384fdd8
Provider= bd935ef1-cc61-4014-a971-1ad76c5e82bf
Consumer= bd935ef1-cc61-4014-a971-1ad76c5e82bf

大功告成！