Spring Cloud 入门 Eureka-Client服务提供

2018-06-18 00:38:29来源：未知阅读 ()

前面文章介绍了如果创建“服务注册中心”，现在创建“服务提供者”，并向服务注册中心注册自己，在服务提供方中尝试着提供一个接口来获取当前所有的服务信息。

先，创建一个基本的Spring Boot应用。命名为eurekaClient，在pom.xml中，加入如下配置：

1、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>

    <groupId>com.example</groupId>
    <artifactId>eurekaClient</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>eurekaClient</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.0.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>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</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>Dalston.SR3</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>

2、Controller

package com.example.demo.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;


@RestController
public class ClientController {

      @Autowired
      DiscoveryClient discoveryClient;
      
      @GetMapping("/all")
      public String dc() {
        String services = "Services: " + discoveryClient.getServices();
        return services;
      }
}

3、EurekaClientApplication 使用@EnableDiscoveryClient注解，该注解能激活Eureka中的DiscoveryClient实现，这样才能实现Controller中对服务信息的输出。

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@EnableDiscoveryClient
@SpringBootApplication
public class EurekaClientApplication {

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

4、application.properties

spring.application.name=eurekaClient
server.port=8001
eureka.client.serviceUrl.defaultZone=http://localhost:8000/eureka/

　　通过spring.application.name属性，我们可以指定微服务的名称后续在调用的时候只需要使用该名称就可以进行服务的访问。eureka.client.serviceUrl.defaultZone属性对应服务注册中心的配置内容，指定服务注册中心的位置。为了在本机上测试区分服务提供方和服务注册中心，使用server.port属性设置不同的端口。

启动该工程后，访问启动好的注册服务http://localhost:8000/，结果：