从零开始学spring cloud(五) -------- 将服务注册到Eureka上

一、开发前准备工作：

官方文档地址：https://cloud.spring.io/spring-cloud-static/spring-cloud-netflix/2.1.0.RELEASE/multi/multi_spring-cloud-eureka-server.html

不同的spring cloud版本的接口地址也是不一样的，可以通过(https://spring.io/projects/spring-cloud-netflix#learn)进行不同版本的文档选择

1.添加Eureka依赖：

To include Eureka Server in your project, use the starter with a group ID of org.springframework.cloud and an artifact ID of spring-cloud-starter-netflix-eureka-server. See the Spring Cloud Project page for details on setting up your build system with the current Spring Cloud Release Train.

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

2.运行Eureka Server

 @SpringBootApplication
 @EnableEurekaServer
 public class EurekaApplication {

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

2.项目实现：

pom文件：

 <?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>
         <groupId>com.zwjk.cloud</groupId>
         <artifactId>microservice-spring-cloud</artifactId>
         <version>0.0.1-SNAPSHOT</version>
     </parent>

     <artifactId>microservice-doscovey-eureka</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <name>microservice-doscovey-eureka</name>
     <description>Demo project for Spring Boot</description>

     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>

     <dependencies>
         <dependency>
             <groupId>org.springframework.cloud</groupId>
             <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
         </dependency>
     </dependencies>

 </project>

application.yml

server:
  port: 8761
eureka:
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://localhost:8761/eureka

EurekaApplication.java

 package com.zwjk.cloud;

 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

 @SpringBootApplication
 @EnableEurekaServer
 public class EurekaApplication {

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

启动项目：

http://localhost:8761/

打开地址后，直接就进入了页面。缺少账号密码验证，

如何在控制台增加账号密码控制呢？

首先，需要在pom文件中，增加权限认证的依赖：

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

接着修改 application.yml

spring:
  security:
    user:
      name: user
      password: password123

server:
  port: 8761
eureka:
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://user:password123@localhost:8761/eureka

同时启动类里面也需要加入一下修改，不然，其他服务来Eureka中注册是，会出现权限认证失败的问题

修改后的启动类如下：

package com.zwjk.cloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
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;

@SpringBootApplication
@EnableEurekaServer
public class EurekaApplication {

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

    @EnableWebSecurity
    static class WebSecurityConfig extends WebSecurityConfigurerAdapter {
        @Override
        protected void configure(HttpSecurity http) throws Exception {

            //Howard 2019-03-20,错误的做法：
            //http.csrf().disable();//这样会直接取消验证账号密码了

            //Howard 2019-03-20，注意 正确的做法是这样：
            http.csrf().disable().authorizeRequests()
                .anyRequest()
                .authenticated()
                .and()
                .httpBasic();
        }
    }
}

启动项目，然后通过浏览器访问http://localhost:8761/

输入密码后，进入Eureka管理后台界面。

二、将服务注册到Eureka上

1.user服务注册到Eureka上，

首先，需要使用Eureka Client将服务注册到Eureka上，需要添加如下的依赖

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

修改配置文件，将Eureka的服务地址及认证，添加到配置文件中

eureka:
  client:
    healthcheck:
      enabled: true
    serviceUrl:
      defaultZone: http://user:password123@localhost:8761/eureka
  instance:
    prefer-ip-address: true
    instance-id: ${spring.application.name}:${spring.application.instance_id:${server.port}}
    metadata-map:
      zone: ABC      # eureka可以理解的元数据
      lilizhou: BBC  # 不会影响客户端行为
    lease-renewal-interval-in-seconds: 5

这个时候，启动user服务，会发现启动失败，

提示健康检查的错误，是因为还需要添加一个依赖

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

重启项目，访问Eureka控制台，

会看到服务已经注册到Eureka上，服务的名字配置文件中applocation.name   Status 是Eureka.instance.instance-id

下面我们将movie也注册到Eureka上

到此，已经将服务都注册到Eureka上了