SpringBoot2.x系列教程14-SpringCloud组件-Eureka01

Eureka在微服务中充当的作用是服务的发现和注册，根据充当的功能角色的不同，Eureka可分为Eureka Server和Eureka Client，Eureka Server的作用是充当系统的服务注册中心，集群方式部署的时候本身既是一个注册中心又是一个服务的提供者；Eureka Client是一个服务的提供者，所起的作用将自身提供的服务注册到注册中心中供其他的服务调用，围绕着Eureka的作用将从下面的几个部分展开讲解。

单机版本Eureka Server及Eureka Client

接下来开始针对单机版本的Eureka Server和Eureka Client创建两个springboot的项目，不过创建的过程中需要分别引入springcloud的实现组件Eureka的相关依赖，核心的依赖主要如下

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>2020.0.3</spring-cloud.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-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>

---

1、Eureka　Server和Eureka Client依赖完整配置

<?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>2.5.3</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.kkcl</groupId>
	<artifactId>coding</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>coding</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>1.8</java.version>
		<spring-cloud.version>2020.0.3</spring-cloud.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-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>

配置文件和主启动类

1、Eureka-Server

配置文件

server.port=8000

#集成Eureka相关配置
eureka.instance.hostname=127.0.0.1

#是否向注册中心注册
eureka.client.register-with-eureka=false
#是否检索服务
eureka.client.fetch-registry=false
#配置服务中心的内容，指定注册中心的位置
eureka.client.serviceUrl.defaultZone=http://127.0.0.1:8000/eureka/

主启动类

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

@EnableEurekaServer
@SpringBootApplication
public class CodingApplication {

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

2、Eureka-Client

配置文件

server.port=8001
#服务的名称
spring.application.name=eureka-client01
#服务注册中心的地址
eureka.client.service-url.defaultZone=http://127.0.0.1:8000/eureka/

主启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.HashMap;
import java.util.Map;

@EnableEurekaClient
@SpringBootApplication
public class CodingApplication {

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

测试

在完成上述的工作后，分别启动Eureka Server和Eureka Client，并访问http://localhost/8000，如果能看到下面的显示效果，说明搭建单机版本模式Eureka Server和Eureka Client成功了。

参考资料

[1]、https://blog.youkuaiyun.com/weixin_45267102/article/details/109169600