Spring Kafka整合Spring Boot创建生产者客户端案例
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创建一个kafka-producer-master的maven工程。整个项目结构如下:
Maven的依赖
<?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.gzh.kafka.producer</groupId> <artifactId>producer</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>kafka-producer-master</name> <description>demo project for kafka producer</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <spring-kafka.version>2.1.5.RELEASE</spring-kafka.version> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <!-- https://mvnrepository.com/artifact/org.springframework.kafka/spring-kafka --> <dependency> <groupId>org.springframework.kafka</groupId> <artifactId>spring-kafka</artifactId> <version>${spring-kafka.version}</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- https://mvnrepository.com/artifact/org.springframework.kafka/spring-kafka-test --> <dependency> <groupId>org.springframework.kafka</groupId> <artifactId>spring-kafka-test</artifactId> <version>${spring-kafka.version}</version> <scope>test</scope> </dependency> <!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger2 --> <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-swagger2</artifactId> <version>2.8.0</version> </dependency> <!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger-ui --> <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-swagger-ui</artifactId> <version>2.8.0</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
使用application.properties配置应用程序
当然,根据个人喜好,你也可以使用application.yml属性文件重写配置。Spring Boot会尝试根据pom.xml文件中指定的依赖关系自动配置应用程序,并设置合理的默认值。
server.port=8000 spring.application.name=kafka-producer #kafka configuration spring.kafka.producer.bootstrap-servers=192.168.1.130:9092,192.168.1.101:9093,192.168.1.101:9094 spring.kafka.producer.key-serializer=org.apache.kafka.common.serialization.StringSerializer spring.kafka.producer.value-serializer=org.apache.kafka.common.serialization.StringSerializer #topic kafka.app.topic.foo=test20180430
在上面的配置中,我给生产者分配的端口号是8000,服务器有3台,采用先前window环境搭建zookeeper,kafka集群 中配置的服务器。想了解关于kafka生产者相关的更多配置的话,可以阅读关于Spring Boot Kafka Properties的配置信息。
使用Spring Boot发送Spring Kafka消息
SpringKafka提供了使用Producer的KafkaTemplate类发送消息,并提供将数据发送到Kafka主题的高级操作。 提供异步和同步方法,异步方法返回Future。Spring Boot根据application.properties属性文件中配置的属性自动配置并初始化KafkaTemplate。为了方便测试发送消息,使用了Spring的定时任务,在类上使用@EnableScheduling 注解开启定时任务,通过@Scheduled注解指定发送消息规则。
package com.gzh.kafka.producer.component; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.kafka.core.KafkaTemplate; import org.springframework.kafka.support.SendResult; import org.springframework.scheduling.annotation.EnableScheduling; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Component; import org.springframework.util.concurrent.ListenableFuture; @Component @EnableScheduling public class KafkaMessageProducer { private static final Logger LOG = LoggerFactory.getLogger(KafkaMessageProducer.class); @Autowired private KafkaTemplate<String, String> kafkaTemplate; @Value("${kafka.app.topic.foo}") private String topic; @Scheduled(cron = "00/5 * * * * ?") public void send() { String message = "Hello World---" + System.currentTimeMillis(); LOG.info("topic="+topic+",message="+message); ListenableFuture<SendResult<String, String>> future = kafkaTemplate.send(topic, message); future.addCallback(success -> LOG.info("KafkaMessageProducer 发送消息成功!"), fail -> LOG.error("KafkaMessageProducer 发送消息失败!")); } }
创建消息生产者启动类
package com.gzh.kafka.producer; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.context.properties.EnableConfigurationProperties; @SpringBootApplication @EnableConfigurationProperties public class KafkaProducerApplication{ public static void main(String[] args) { SpringApplication.run(KafkaProducerApplication.class, args); } }
至此,Spring Boot整合Spring Kafka消息生产者应用已经整合完毕。启动zookeeper、kafka各个服务器。启动生产者应用,查看消息生产者应用控制台日志,如下图说明整合OK。
当然在创建消息生产者类时,我们可以更加灵活,可以不使用定时任务,通过界面请求的方式,发送我们想要发送的内容。简单案例如下:
- 消息发送者类
package com.gzh.kafka.producer.service; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.kafka.core.KafkaTemplate; import org.springframework.kafka.support.SendResult; import org.springframework.stereotype.Service; import org.springframework.util.concurrent.ListenableFuture; @Service public class KafkaMessageSendService { private static final Logger LOG = LoggerFactory.getLogger(KafkaMessageSendService.class); @Autowired private KafkaTemplate<String, String> kafkaTemplate; @Value("${kafka.app.topic.foo}") private String topic; public void send(String message){ LOG.info("topic="+topic+",message="+message); ListenableFuture<SendResult<String, String>> future = kafkaTemplate.send(topic, message); future.addCallback(success -> LOG.info("KafkaMessageProducer 发送消息成功!"), fail -> LOG.error("KafkaMessageProducer 发送消息失败!")); } }
- 界面请求处理controller类
package com.gzh.kafka.producer.controller; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.http.MediaType; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; import com.gzh.kafka.producer.service.KafkaMessageSendService; @RestController @RequestMapping(value="send",produces=MediaType.APPLICATION_JSON_UTF8_VALUE) public class KafkaMessageSendController { @Autowired private KafkaMessageSendService kafkaMessageSendService; @RequestMapping(value="/sendMessage",method=RequestMethod.POST) public String send(@RequestParam(required=true) String message){ try { kafkaMessageSendService.send(message); } catch (Exception e) { return "send failed."; } return message; } }
- 通过Swagger访问测试Controller服务请求
Spring Kafka整合Spring Boot创建消费者客户端案例:
创建一个kafka-consumer-master的maven工程。整个项目结构如下:
Maven的依赖
<?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.gzh.kafka.consumer</groupId> <artifactId>consumer</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>kafka-consumer-master</name> <description>demo project for kafka consumer</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <spring-kafka.version>1.3.4.RELEASE</spring-kafka.version> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <!-- https://mvnrepository.com/artifact/org.springframework.kafka/spring-kafka --> <dependency> <groupId>org.springframework.kafka</groupId> <artifactId>spring-kafka</artifactId> <version>${spring-kafka.version}</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- https://mvnrepository.com/artifact/org.springframework.kafka/spring-kafka-test --> <dependency> <groupId>org.springframework.kafka</groupId> <artifactId>spring-kafka-test</artifactId> <version>${spring-kafka.version}</version> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
注意,这是使用Spring-Kafka时一定要注意版本问题,否则会报各种奇葩错误。Spring官方网站上给出了SpringKafka和kafka-client版本(它的版本号要和kafka服务器的版本保持一致)的对应关系:
使用application.properties配置应用程序
Spring Boot会尝试根据pom.xml文件中指定的依赖关系自动配置应用程序,并设置合理的默认值。
server.port=8001 spring.application.name=kafka-consumer #kafka configuration #指定消息被消费之后自动提交偏移量,以便下次继续消费 spring.kafka.consumer.enable-auto-commit=true #指定消息组 spring.kafka.consumer.group-id=guan #指定kafka服务器地址 spring.kafka.consumer.bootstrap-servers=192.168.1.130:9092,192.168.1.101:9093,192.168.1.101:9094 #指定从最近地方开始消费(earliest) spring.kafka.consumer.auto-offset-reset=latest spring.kafka.consumer.key-deserializer=org.apache.kafka.common.serialization.StringDeserializer spring.kafka.consumer.value-deserializer=org.apache.kafka.common.serialization.StringDeserializer #topic kafka.app.topic.foo=test20180430
在上面的配置中,我给生产者分配的端口号是8000,服务器有3台,采用先前window环境搭建zookeeper,kafka集群 中配置的服务器。想了解关于kafka生产者相关的更多配置的话,可以阅读关于Spring Boot Kafka Properties的配置信息。
使用Spring Boot消费Spring Kafka消息
通过使用@KafkaListener来注解一个方法Spring Kafka会自动创建一个消息监听器容器。使用该注解,并指定要消费的topic(也可以指定消费组以及分区号,支持正则表达式匹配),这样,消费者一旦启动,就会监听kafka服务器上的topic,实时进行消费消息。
package com.gzh.kafka.consumer.service; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.kafka.annotation.KafkaListener; import org.springframework.messaging.MessageHeaders; import org.springframework.messaging.handler.annotation.Headers; import org.springframework.messaging.handler.annotation.Payload; import org.springframework.stereotype.Component; @Component public class KafkaMessageConsumer { private static final Logger LOG = LoggerFactory.getLogger(KafkaMessageConsumer.class); @KafkaListener(topics={"${kafka.app.topic.foo}"}) public void receive(@Payload String message, @Headers MessageHeaders headers){ LOG.info("KafkaMessageConsumer 接收到消息:"+message); headers.keySet().forEach(key->LOG.info("{}: {}",key,headers.get(key))); } }
创建消息消费者启动类
package com.gzh.kafka.consumer; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.context.properties.EnableConfigurationProperties; @SpringBootApplication @EnableConfigurationProperties public class KafkaConsumerApplication { public static void main(String[] args) { SpringApplication.run(KafkaConsumerApplication.class, args); } }
消费者应用已经完成,接下来让我们验证Spring Kafka消息发送和接收效果。先依次启动zookeeper、kafka服务器,然后在启动生产者(kafka-producer-master)应用,再启动消费者(kafka-consumer-master)应用,然后观察生产者和消费者启动类日志: