Eureka Server的使用

1. eureka组件

Eureka Server 和 Eureka Client

调用过程：

1. 服务提供者启动时向服务注册中心注册自己的服务。

2. 服务消费者启动时向服务注册中心订阅自己所需要的服务。

3. 注册中心将服务提供者地址提供给消费者。

4. 服务消费者通过地址进行消费。

2. 注册中心搭建

pom.xml

　　<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.RELEASE</version>
　　</parent>

    <properties>
        <spring-cloud.version>Finchley.RELEASE</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.18</version>
        </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>

    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>    

启动类

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

application.yml

spring:
  application:
    name: ad-eureka #服务名

server:
  port: 8000

eureka:
  instance:
    hostname: localhost
  client:
    fetch-registry: false #是否从eureka获取信息
    register-with-eureka: false #是否注册到eureka（自身是不需要注册到自己的）
    service-url:
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

application.yml（关于两两注册）

spring:
  application:
    name: ad-eureka
  profiles: server1
server:
  port: 8000
eureka:
  instance:
    hostname: server1
    prefer-ip-address: false
  client:
    service-url:
      defaultZone: http://server2:8001/eureka/,http://server3:8002/eureka/

---
spring:
  application:
    name: ad-eureka
  profiles: server2
server:
  port: 8001
eureka:
  instance:
    hostname: server2
    prefer-ip-address: false
  client:
    service-url:
      defaultZone: http://server1:8000/eureka/,http://server3:8002/eureka/

---
spring:
  application:
    name: ad-eureka
  profiles: server3
server:
  port: 8002
eureka:
  instance:
    hostname: server3
    prefer-ip-address: false
  client:
    service-url:
      defaultZone: http://server1:8000/eureka/,http://server2:8001/eureka/

当然，此时还得在C:WindowsSystem32driversetchosts文件中进行映射

127.0.0.1    server1
127.0.0.1    server2
127.0.0.1    server3

启动后