構建高可用Eureka註冊中心

Eureka通過執行多個例項，使其更具有高可用性。

建立一個maven工程micro-erueka-server（micro-parent參見第一篇），pom.xml如下：

<?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>
	<artifactId>micro-eureka-server</artifactId>
	<packaging>jar</packaging>
	<name>micro-eureka-server</name>
	<description>微服務學習</description>	
	<parent>
		<groupId>com.sun</groupId>
		<artifactId>micro-parent</artifactId>
	    <version>0.0.1-SNAPSHOT</version>
	</parent>
	
	<dependencies>
	 	 <dependency>
	      	<groupId>org.springframework.cloud</groupId>
	      	<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
	     </dependency>
	</dependencies>
	
</project>
 

啟動類需要加上@EnableEurekaServer註解如下：

package com.sun.eureka;

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);
	}
}
 

配置檔案application.yml中配置兩套profiles 8080埠的ha1和8081埠的ha2,這裡注意eureka.client.serviceUrl.defaultZone配置項的地址，不能使用localhost，要使用域名，自己修改hosts檔案即可，具體配置如下：

spring:
  application:
    name: micro-erueka-server
---
server:
  port: 8080
spring:
  profiles: ha1 
eureka:
  instance:
    hostname: peer1
  client:
    service-url:
      defaultZone: http://peer2:8081/eureka
---
server:
  port: 8081
spring:
  profiles: ha2 
eureka:
  instance:
    hostname: peer2
  client:
    service-url:
      defaultZone: http://peer1:8080/eureka
 

 eclipse 右擊run as configurations 配置兩套啟動配置profile分別為ha1,ha2

分別執行配置的ha1,ha2,訪問http://localhost:8080/,可以看到如下8081和8080已經註冊到了eureka server上，並且8080的available-replicas是8081，這裡如果出現在unavailable-replicas說明沒有形成高可用

為eureka新增使用者認證

pom.xml中新增依賴：

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

application.yml修改為：

spring:
  security:  #設定登入認證
    user:
      name: user
      password: opop
      roles: USER
  application:
    name: micro-erueka-server
---
server:
  port: 8080
spring:
  profiles: ha1 
eureka:
  instance:
    hostname: peer1
  client:
    service-url:
      defaultZone: http://user:[email protected]:8081/eureka #這裡要使用使用者名稱密碼
---
server:
  port: 8081
spring:
  profiles: ha2 
eureka:
  instance:
    hostname: peer2
  client:
    service-url:
      defaultZone: http://user:[email protected]:8080/eureka #這裡要使用使用者名稱密碼

由於Finchey版本預設開啟csrf  為了可以使用 http://${userName}:${password}@${host}:${port}/eureka/ 這種方式登入,所以寫一個配置類關掉它

package com.sun.eureka.config;
import org.springframework.context.annotation.Configuration;
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;
import org.springframework.security.config.http.SessionCreationPolicy;

@EnableWebSecurity
@Configuration
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.sessionManagement().sessionCreationPolicy(SessionCreationPolicy.NEVER);
        http.csrf().disable(); //關閉csrf
        http.authorizeRequests().anyRequest().authenticated().and().httpBasic(); //開啟認證
    }

}

這時啟動再訪問，需要輸入使用者名稱密碼：