Spring Cloud 微服务开发:入门、进阶与源码剖析 —— 2.3 Spring Cloud Eureka 实战

本文介绍了如何在Spring Cloud Eureka中设置Zone和Region,通过示例展示了如何配置Eureka Server和Client。还探讨了开启HTTP Basic认证以增强Eureka Server的安全性,包括配置Spring Security并禁用CSRF校验。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

2.3 Spring Cloud Eureka 实战

2.3.1 Eureka Zone与Region实战

这里需要创建2个Eureka Server,分为2个Zone,同属于shanghai这个Region。其中Eureka Server的配置文件代码如下:

  1. 创建Eureka Server工程:

    代码清单:ch2_2/ch2_2_eureka_server_1/src/main/resources/application.yml


    spring:
      application:
        name: spring-cloud-eureka-1
    server:
      port: 8761
    eureka:
      instance:
        hostname: localhost
        metadata-map:
          zone: zone-1
      client:
        register-with-eureka: false
        fetch-registry: false
        prefer-same-zone-eureka: true
        region: shanghai
        availability-zones:
          shanghai: zone-1, zone-2
        service-url:
          zone-1: http://localhost:8761/eureka/
          zone-2: http://localhost:8762/eureka/
      server:
        enable-self-preservation: false
        wait-time-in-ms-when-sync-empty: 0
    

    代码清单:ch2_2/ch_2_eureka_server_2/src/main/resources/application.yml


    spring:
      application:
        name: spring-cloud-eureka-2
    server:
      port: 8762
    eureka:
      instance:
        hostname: localhost
        metadata-map:
          zone: zone-2
      client:
        register-with-eureka: false
        fetch-registry: false
        prefer-same-zone-eureka: true
        region: shanghai
        availability-zones:
          shanghai: zone-1, zone-2
        service-url:
          zone-1: http://localhost:8761/eureka/
          zone-2: http://localhost:8762/eureka/
      server:
        enable-self-preservation: false
        wait-time-in-ms-when-sync-empty: 0
    
    • eureka.client.prefer-same-zone-eureka:为true优先选择client实例所在的zone的服务
    • eureka.client.region:标识当前所属region
    • eureka.client.availability-zones:当前可用的Zones
    • eureka.client.service-url:这里需要分开Zone做配置

    再创建2个Eureka Client端,分别属于Zone1和Zone2中,如下:

  2. 创建Eureka Client工程

    代码清单:ch2_2/ch2_2_eureka_client_1/src/main/resources/application.yml


    server:
      port: 8080
    spring:
      application:
        name: spring-cloud-eureka-client
    eureka:
      instance:
        prefer-ip-address: true
        metadata-map:
          zone: zone-1
      client:
        prefer-same-zone-eureka: true
        region: shanghai
        availability-zones:
          shanghai: zone-1, zone-2
        service-url:
          zone-1: http://localhost:8761/eureka/
          zone-2: http://localhost:8762/eureka/
    

    代码清单:ch2_2/ch2_2_eureka_client_1/src/main/resources/application.yml


    server:
      port: 8081
    spring:
      application:
        name: spring-cloud-eureka-client
    eureka:
      instance:
        prefer-ip-address: true
        metadata-map:
          zone: zone-2
      client:
        prefer-same-zone-eureka: true
        region: shanghai
        availability-zones:
          shanghai: zone-1, zone-2
        service-url:
          zone-1: http://localhost:8761/eureka/
          zone-2: http://localhost:8762/eureka/
    

    在Eureka Client端添加一个HelloController.java,用作后续测试:

    代码清单:ch2_2/ch2_2_eureka_client_1/src/main/java/com/springcloud/book/ch2_2_eureka_client_1/controller/HelloController.java


    package com.springcloud.book.ch2_2_eureka_client_2.controller;
    
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    /**
    * @Date: 2019/7/24 9:28
    * @Version: 1.0
    * @Desc:
    */
    @RestController
    public class HelloController {
    
        @GetMapping("/hello")
        public String hi() {
            return "Hello, this is Zone-1";
        }
    }
    

    代码清单:ch2_2/ch2_2_eureka_client_2/src/main/java/com/springcloud/book/ch2_2_eureka_client_2/controller/HelloController.java


    package com.springcloud.book.ch2_2_eureka_client_2.controller;
    
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    /**
    * @Date: 2019/7/24 9:28
    * @Version: 1.0
    * @Desc:
    */
    @RestController
    public class HelloController {
    
        @GetMapping("/hello")
        public String hi() {
            return "Hello, this is Zone-2";
        }
    }
    

    以上,我们在Eureka Client端提供了一个Hello方法,顺次启动2个Eureka Server和2个Eureka Client后,在浏览器分别访问http://localhost:8080/hello和http://localhost:8081/hello,浏览器可以正常显示Hello, this is Zone-1和Hello, this is Zone-2,证明Eureka Client可以正常提供hello服务。

  3. 创建consumer工程

    项目依赖pom.xml

    代码清单:ch2_2/ch2_2_eureka_consumer/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>
        <parent>
            <artifactId>ch2_2</artifactId>
            <groupId>com.springcloud.book</groupId>
            <version>0.0.1-SNAPSHOT</version>
            <relativePath>../pom.xml</relativePath>
        </parent>
        <artifactId>ch2_2_eureka_consumer</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>ch2_2_eureka_consumer</name>
        <description>ch2_2_eureka_consumer</description>
    
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
            <java.version>1.8</java.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-client</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-openfeign</artifactId>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>
    
    • openfeign:声明式Web Service客户端,后面会详细介绍。

    配置文件:

    代码清单:ch2_2/ch2_2_eureka_consumer/src/main/resources/application.yml


    spring:
      application:
        name: spring-cloud-eureka-consumer
    server:
      port: 8000
    eureka:
      instance:
        prefer-ip-address: true
        metadata-map:
          zone: zone-1
      client:
        register-with-eureka: true
        fetch-registry: true
        prefer-same-zone-eureka: true
        region: shanghai
        availability-zones:
          shanghai: zone-1,zone-2
        service-url:
          zone-1: http://localhost:8761/eureka/
          zone-2: http://localhost:8762/eureka/
    

    创建HelloRemote.java

    代码清单:ch2_2/ch2_2_eureka_consumer/src/main/java/com/springcloud/book/ch2_2_eureka_consumer/remote/HelloRemote.java

    package com.springcloud.book.ch2_2_eureka_consumer.remote;
    
    import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    /**
    * @Date: 2019/7/24 10:37
    * @Version: 1.0
    * @Desc:
    */
    @FeignClient(name= "spring-cloud-eureka-client")
    public interface HelloRemote {
    
        @RequestMapping(value = "/hello")
        String hello();
    
    }
    

    创建HelloController.java

    代码清单:ch2_2/ch2_2_eureka_consumer/src/main/java/com/springcloud/book/ch2_2_eureka_consumer/controller/HelloController.java


    package com.springcloud.book.ch2_2_eureka_consumer.controller;
    
    import com.springcloud.book.ch2_2_eureka_consumer.remote.HelloRemote;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    /**
    * @Date: 2019/7/24 10:40
    * @Version: 1.0
    * @Desc:
    */
    @RestController
    public class HelloController {
    
        @Autowired
        HelloRemote helloRemote;
    
        @RequestMapping("/hello")
        public String index() {
            return helloRemote.hello();
        }
    }
    

    到这里,整个测试样例已经构建完成,现在可以顺次启动Eureka Server、Eureka Client、Consumer。

    首先在浏览器中访问:http://localhost:8000/hello ,页面正常返回Hello, this is Zone-1,刷新多次后,并无变化,说明消费者消费就近原则,消费Zone-1成功,并不会消费到Zone-2中,这时,我们停止Eureka Client1的服务,再去刷新浏览器http://localhost:8000/hello ,这时可以看到,页面跳转到500,并且刷新有等待时间,这是Eureka的本地缓存,稍等一会后,等缓存过期,再次刷新浏览器,可以看到页面返回Hello, this is Zone-2,证明,我们的服务已经转到Zone-2中了,测试成功。

2.3.2 开启HTTP Basic认证

在生产环境中,往往需要考虑安全问题,Eureka Server对外暴露的REST API,如果没有安全验证,是一件非常危险的事情,任何人都可以通过Eureka Server的REST API随意更改服务的注册信息,造成服务异常,这里我们可以集成Spring Security来对Eureka Server做访问权限控制,只有验证通过的客户端才能在Eureka Server正常的注册、修改、注销服务实例。

  1. 创建Eureka Server

    工程依赖增加spring-boot-starter-security,pom.xml如下:

    代码清单:ch2_3/ch2_3_eureka_server/pom.xml


    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    

    由于篇幅原因,这里仅展示新增部分,更多详细内容可以访问Github仓库。

    配置文件如下:

    代码清单:ch2_3/ch2_3_eureka_server/src/main/resources/application-security.yml


    server:
      port: 8761
    eureka:
      instance:
        hostname: localhost
      client:
        register-with-eureka: false
        fetch-registry: false
        service-url:
          defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/
      server:
        enable-self-preservation: false
        wait-time-in-ms-when-sync-empty: 0
    spring:
      security:
        user:
          name: admin
          password: 809d3ffb-6860-45a7-b395-123e26af8e42
    
    • spring.security.user.name:security用户名
    • spring.security.user.password:security密码

    由于spring-boot-starter-security默认开启了CSRF校验,当Spring Security在classpath路径下,它将要求每个客户端请求带上CSRF TOKEN,Eureka Client端通常不会拥有一个有效的CSRF TOKEN。但是没有配置文件的方式禁用,需要自己写Java配置来禁用,代码如下:

    代码清单:ch2_3/ch2_3_eureka_server/src/main/java/com/springcloud/book/ch2_3_eureka_server_security/config/WebSecurityConfig.java


    package com.springcloud.book.ch2_3_eureka_server_security.config;
    
    import org.springframework.security.config.annotation.web.builders.HttpSecurity;
    import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
    import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
    
    /**
    * @Date: 2019/7/23 14:39
    * @Version: 1.0
    * @Desc:
    */
    @EnableWebSecurity
    public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
    
        @Override
        protected void configure(HttpSecurity http) throws Exception {
            super.configure(http);
            http.csrf().disable().httpBasic();
        }
    }
    
    

    然后启动Eureka Server,打开浏览器访问:http://localhost:8761 ,结果如图2-10所示:

    图2-10 Eureka Server 登录界面

    这里需要我们输入刚才在配置文件中配置的用户名和密码才能登录。

  2. 创建Eureka Client

    配置文件:

    代码清单:ch2_3/ch2_3_eureka_client/src/main/resources/application.yml


    server:
      port: 8080
    spring:
      application:
        name: spring-cloud-eureka-client
    eureka:
      client:
        service-url:
          defaultZone: http://admin:809d3ffb-6860-45a7-b395-123e26af8e42@localhost:8761/eureka/
    
    • defaultZone:这里的格式为http://{username}:{password}@localhost:8761/eureka/

    启动Eureka Client,看一下Eureka Server的UI,可以看到Eureka Client已经正常注册在Eureka Server上。

评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包

打赏作者

极客挖掘机

你的鼓励将是我创作的最大动力

¥1 ¥2 ¥4 ¥6 ¥10 ¥20
扫码支付:¥1
获取中
扫码支付

您的余额不足,请更换扫码支付或充值

打赏作者

实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值