利用Spring Cloud Netflix提供的模块可以非常方便快速的搭建起一套spring boot的分布式环境,服务发现模块(Eureka)是Netflix的核心。
大费口舌解释Eureka是什么,不如动手搭一套Netflix的spring boot分布式环境,当整套环境搭起来以后,估计你也理解得差不多了。
1. 创建Eureka服务注册中心
创建spring boot工程最简单的方式,访问 http://start.spring.io/ ,填写artifact,dependencies添加 "Eureka Server",点击"Generate Project" 就可以下载生成的spring boot工程。
生成spring boot工程
生成的pom.xml已经有相关的dependancies
<?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>
<groupId>com.example</groupId>
<artifactId>eureka</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>eureka</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Dalston.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-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>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
修改EurekaApplication.java,只需增加一行@EnableEurekaServer就可以将spring boot应用改造成Eureka服务注册中心
package com.example;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@EnableEurekaServer
@SpringBootApplication
public class Application {
public static void main(String[] args) {
new SpringApplicationBuilder(Application.class).web(true).run(args);
}
}
在application.properties增加如下配置
server.port=2000
eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false
eureka.client.serviceUrl.defaultZone=http://localhost:${server.port}/eureka/
打包工程,在工程的根目录执行命令
mvn package
打包完成后可以看到target目录下有了eureka-0.0.1-SNAPSHOT.jar,直接运行
java -jar target\eureka-0.0.1-SNAPSHOT.jar
启动完成,浏览器访问 http://localhost:2000/ 看到Eureka的界面,服务注册中心搭建完成。
Eureka服务注册中心管理页面