springcolud-eureka

1 介绍

1、Spring-Cloud Euraka介绍

Spring-Cloud Euraka是Spring Cloud集合中一个组件，它是对Euraka的集成，用于服务注册和发现。Eureka是Netflix中的一个开源框架。它和 zookeeper、Consul一样，都是用于服务注册管理的，同样，Spring-Cloud 还集成了Zookeeper和Consul。

在项目中使用Spring Cloud Euraka的原因是它可以利用Spring Cloud Netfilix中其他的组件，如zull等，因为Euraka是属于Netfilix的。

2、Euraka介绍

Eureka由多个instance(服务实例)组成，这些服务实例可以分为两种：Eureka Server和Eureka Client。为了便于理解，我们将Eureka client再分为Service Provider和Service Consumer。

• Eureka Server 提供服务注册和发现
• Service Provider 服务提供方，将自身服务注册到Eureka，从而使服务消费方能够找到
• Service Consumer服务消费方，从Eureka获取注册服务列表，从而能够消费服务3.项目中的实际应用
• 1.新建一个Springcloud工程：工程名：eureka, jdk8,springcloud的版本：Edgware.RELEASE

• <?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
      <modelVersion>4.0.0</modelVersion>
      <parent>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-parent</artifactId>
          <version>1.5.1.RELEASE</version>
          <relativePath/> <!-- lookup parent from repository -->
      </parent>
      <groupId>com.chinasoft</groupId>
      <artifactId>eureka</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <name>eureka</name>
      <description>Demo project for Spring Boot</description>
      <properties>
          <java.version>1.8</java.version>
          <spring-cloud.version>Edgware.RELEASE</spring-cloud.version>
      </properties>
  
      <dependencies>
          <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>Edgware.RELEASE</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>
      <repositories>
          <repository>
              <id>spring-milestones</id>
              <name>Spring Milestones</name>
              <url>https://repo.spring.io/milestone</url>
              <snapshots>
                  <enabled>false</enabled>
              </snapshots>
          </repository>
      </repositories>
  
  </project>

   2.application.yml

• server:
    port: 6001
  spring:
    application:
      name: eureka #应用名称
  eureka:
    instance:
      appname: eureka-server #服务名
      hostname: localhost #应用实例主机名
      prefer-ip-address: true #客户端在注册的时候使用自己的IP而不是主机名
    client:
      register-with-eureka: false #是否将自己注册到eureka
      fetch-registry: false #服务发现，是否从Eureka中获取注册信息
      service-url:
        defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/
    server:
      # 自我保护
      enable-self-preservation: false
      # 主动检查服务时间
      eviction-interval-timer-in-ms: 5000
      # 服务过期时间，超过这个时间剔除服务
      lease-expiration-duration-in-seconds: 10
      # 服务刷新时间 主动心跳
      lease-renewal-interval-in-seconds: 5
      # 禁用readOnlyCacheMap
      useReadOnlyResponseCache: false
  

  　　3.EurekaApplication.java

    

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

 

 

3.2创建一个服务消费者的工程：eureka_consumer,

3.2.1 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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.chinasoft</groupId>
    <artifactId>eureka_consumer</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>eureka_consumer</name>
    <description>spring-cloud eureka consumer</description>
    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Edgware.RELEASE</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</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>Edgware.RELEASE</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>
    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

</project>

2.application.yml

server:
  port: 7001
spring:
  application:
    name: eureka_consumer
##此方法是把工程中服务注册到端口为6001，工程为eureka中去；
eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:6001/eureka/
  instance:
    prefer-ip-address: true
    ip-address: ${IP_ADDRESS:127.0.0.1}
    instance-id: ${spring.application.name}:${server.port} #eureka服务中心的名字 ucenter：7001

3.EurekaConsumerApplication.java

@SpringBootApplication
//servlet扫描器
@ServletComponentScan
//开启eureka客户端，启动的时候会被eureka发现并注册到服务中心
@EnableDiscoveryClient
public class EurekaConsumerApplication {

    public static void main(String[] args) {
        SpringApplication.run(EurekaConsumerApplication.class, args);
    }

}

4.TestController.java

@RestController
public class TestController {
    @GetMapping("/getuserinfo/{id}")
    public String get(@PathVariable("id") Long id) {
        return "用户信息：" + id;
    }
}

效果展示：