在微服务架构中,经常会遇到服务注册与发现的组件,下面重新认识一下springcloud中的eureka组件。
开门见山,上实例,具体原理参考官网。
1依赖
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>2020.0.4</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
2application.properties
spring.application.name=eureka
server.port=9001
eureka.instance.hostname=localhost
eureka.client.service-url.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/
eureka.client.fetch-registry=false
eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false为不去获取服务列表
eureka.client.register-with-eureka=false为本身不去注册
3代码
@SpringBootApplication
@EnableEurekaServer
public class EurekaApplication {
public static void main(String[] args) {
SpringApplication.run(EurekaApplication.class, args);
}
}
4监听
@Configuration
public class InstanceCancelListener implements ApplicationListener<EurekaInstanceCanceledEvent> {
@Override
public void onApplicationEvent(EurekaInstanceCanceledEvent event) {
System.out.println(String.format("服务:%s挂了",event.getAppName()));
}
}
@Configuration
public class InstanceRegisterListener implements ApplicationListener<EurekaInstanceRegisteredEvent> {
@Override
public void onApplicationEvent(EurekaInstanceRegisteredEvent event) {
System.out.println(String.format("服务:%s,注册成功了",event.getInstanceInfo().getAppName()));
}
}
@Configuration
public class InstanceRenewListener implements ApplicationListener<EurekaInstanceRenewedEvent> {
@Override
public void onApplicationEvent(EurekaInstanceRenewedEvent event) {
System.out.println(String.format("心跳检测服务:%s",event.getInstanceInfo().getAppName()));
}
}
5启动
启动后可访问,如
6测试
新建一个测试工程,在启动类中添加@EnableDiscoveryClient
在配置文件中添加
#使用IP注册
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ip-address}:${server.port}
eureka.client.service-url.defaultZone=http://localhost:9001/eureka/
启动该测试工程,查看eureka网页,如
出现如上即可,eureka服务配置完成。