1.什么是Eureka?
Eureka 由 Netflix 开发,是一种基于REST(Representational State Transfer)的服务,用于定位服务(服务注册与发现),以实现中间层服务的负载均衡和故障转移,此服务被称为 Eureka Server。同时,它还附带了基于 Java 的客户端组件:Eureka Client,它使得客户端与 Eureka Server 的交互变得更加的容易。 以下就是一个简单的服务调用过程:
- 由服务提供方将服务注册到 Eureka Server
- 服务消费者通过 Eureka Server 获取服务提供方的真实地址
- 服务消费者通过真实的地址调用服务
2.代码工程
实验目的
搭建Eureka集群
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">
<parent>
<artifactId>eureka</artifactId>
<groupId>com.et</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-server</artifactId>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
<version>${eureka.version}</version>
</dependency>
</dependencies>
</project>
EurekaServerApplication
package com.et.eureka;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@EnableEurekaServer
@SpringBootApplication
public class EurekaServerApplication {
public static void main(String[] args) {
SpringApplication.run(EurekaServerApplication.class, args);
}
}
节点1配置信息
server:
port: 8761
eureka:
instance:
hostname: node1 # eureka name
prefer-ip-address: false
client:
fetch-registry: false
register-with-eureka: true
# eureka url
service-url:
defaultZone: http://node2:8762/eureka
spring:
application:
name: "eureka-server-ha"
节点2配置信息
server:
port: 8762
eureka:
instance:
hostname: node2 # eureka name
prefer-ip-address: false
client:
fetch-registry: false
register-with-eureka: true
# eureka url
service-url:
defaultZone: http://node1:8761/eureka
spring:
application:
name: "eureka-server-ha"
配置本机host
/etc/hosts
127.0.0.1 node1 127.0.0.1 node2
以上只是一些关键代码,所有代码请参见下面代码仓库
代码仓库
- GitHub - Harries/springcloud-demo: Spring Cloud tutorial about hystrix,eureka,config,admin,skywalking
3.测试
启动node1,node2
访问http://127.0.0.1:8761/
4.引用
- Spring Cloud Netflix
- Spring Cloud 3: Eureka Clustering | Nick Li
- Spring Cloud Eureka快读入门Demo | Harries Blog™