(1). 概述
这一小节,主要把Kafka与SpringBoot进行集成,并能发送和接受消息.
(2). 项目结构
lixin-macbook:kafka-example lixin$ tree
.
├── pom.xml
├── src
│ ├── main
│ │ ├── java
│ │ │ └── help
│ │ │ └── lixin
│ │ │ └── kafka
│ │ │ └── example
│ │ │ ├── KafkaApplication.java
│ │ │ ├── consumer
│ │ │ │ └── MessageRevice.java
│ │ │ └── controller
│ │ │ └── MessageController.java
│ │ └── resources
│ │ └── application.yml
└── test-classes
(3). 引入依赖(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>help.lixin.kafka</groupId>
<artifactId>kafka-example</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
<spring-cloud.version>Finchley.RC2</spring-cloud.version>
</properties>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Greenwich.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>2.1.0.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-netflix</artifactId>
<version>2.1.1.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<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>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.kafka</groupId>
<artifactId>spring-kafka</artifactId>
<exclusions>
<exclusion>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>2.8.1</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.4</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
(4). 定义配置(application.yml)文件
server:
port: 8088
spring:
kafka:
bootstrap-servers: 127.0.0.1:9092,127.0.0.1:9093,127.0.0.1:9094
producer:
retries: 3
batch-size: 16384
buffer-memory: 33554432
acsk: -1
key-serializer: org.apache.kafka.common.serialization.StringSerializer
value-serializer: org.apache.kafka.common.serialization.StringSerializer
consumer:
group-id: test-service-1
enable-auto-commit: false
auto-offset-reset: earliest
key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
value-deserializer: org.apache.kafka.common.serialization.StringDeserializer
max-poll-records: 500
listener:
# ack-mode: RECORD #
# ack-mode: RECORD
# ack-mode: BATCH
# ack-mode: TIME
# ack-mode: COUNT
# ack-mode: COUNT_TIME
# 手动调用Acknowledgment.acknowledge()后立即提交
ack-mode: MANUAL_IMMEDIATE
(5). MessageController
package help.lixin.kafka.example.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class MessageController {
private String topic = "hello";
@Autowired
private KafkaTemplate<String, Object> kafkaTemplate;
@GetMapping("/send")
public String send() {
kafkaTemplate.send(topic, "Hello World!!!!");
return "SUCCESS";
}
}
(6). MessageRevice
package help.lixin.kafka.example.consumer;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.kafka.support.Acknowledgment;
import org.springframework.stereotype.Component;
@Component
public class MessageRevice {
// concurrency : 代表为:test-group配置2个Consumer去消费,建议:与Partition数量相同.
// @KafkaListener(topics = {"${listener.topic}"}, groupId = "test-group", concurrency = "${listener.concurrency}")
@KafkaListener(topics = {"hello"}, groupId = "test-group", concurrency = "2")
public void listen(ConsumerRecord<String, String> record, Acknowledgment ack) {
System.out.println("Revice Message: " + record.value());
// 手动提交offset
ack.acknowledge();
}
}
(7). KafkaApplication
package help.lixin.kafka.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class KafkaApplication {
public static void main(String[] args) {
SpringApplication.run(KafkaApplication.class, args);
}
}
(8). 总结
Kafka与Spring的整合之后,相当的简单,不过,过于简单的东西就会失去控制性,所以,后面的章节会对Kafka和SpringBoot的整合源码进行剖解.
