搭建Springcloud項目，使用Eureka註冊中心，feign客戶端調用

首先創建一個maven項目，爲Eureka註冊中心項目

依賴引入

<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-parent</artifactId>
		<version>2.0.3.RELEASE</version>
	</parent>
	<!-- 管理依賴 -->
	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>Finchley.RELEASE</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

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

		<!-- jaxb模塊引用 - start -->
		<dependency>
			<groupId>javax.xml.bind</groupId>
			<artifactId>jaxb-api</artifactId>
		</dependency>
		<dependency>
			<groupId>com.sun.xml.bind</groupId>
			<artifactId>jaxb-impl</artifactId>
			<version>2.3.0</version>
		</dependency>
		<dependency>
			<groupId>org.glassfish.jaxb</groupId>
			<artifactId>jaxb-runtime</artifactId>
			<version>2.3.0</version>
		</dependency>
		<dependency>
			<groupId>javax.activation</groupId>
			<artifactId>activation</artifactId>
			<version>1.1.1</version>
		</dependency>
		<!-- jaxb模塊引用 - end -->


	</dependencies>

	<!-- 注意： 這裏必須要添加， 否者各種依賴有問題   -->

	<repositories>
		<repository>
			<id>spring-milestones</id>
			<name>Spring Milestones</name>
			<url>https://repo.spring.io/milestone</url>
			<snapshots>
				<enabled>false</enabled>
			</snapshots>
		</repository>
		<repository>
			<id>repository.springframework.maven.release</id>
			<name>Spring Framework Maven Release Repository</name>
			<url>http://maven.springframework.org/milestone/</url>
		</repository>
		<repository>
			<id>org.springframework</id>
			<url> http://maven.springframework.org/snapshot</url>
		</repository>
		<repository>
			<id>spring-milestone</id>
			<name>Spring Maven MILESTONE Repository</name>
			<url>http://repo.spring.io/libs-milestone</url>
		</repository>
		<repository>
			<id>spring-release</id>
			<name>Spring Maven RELEASE Repository</name>
			<url>http://repo.spring.io/libs-release</url>
		</repository>
	</repositories>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<maven.compiler.source>11.0</maven.compiler.source>
		<maven.compiler.target>11.0</maven.compiler.target>
	</properties>

啓動類

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

@SpringBootApplication
@EnableEurekaServer
public class Eureka_app {

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

application.yml配置文件

#服務端口號
server: 
  port: 8100
spring: 
  application: 
    name: eureka-server
eureka: 
  instance: 
  #註冊中心ip
    hostname: 127.0.0.1
  client: 
    serviceUrl: 
    #註冊地址
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/
    #是否需要把吧本項目註冊到註冊中心
    register-with-eureka: false
    #因爲自己是註冊中心 所以不需要檢索服務
    fetch-registry: false
    #測試時關閉自我保護機制
  server: 
    enable-self-preservation: false
    #剔除失效服務間隔
    eviction-interval-timer-in-ms: 2000

創建一個maven project ，packaging選擇pom，名爲Springcloud-vhukze-parent。

在此項目下新建一個maven model，packaging選擇pom，名爲Springcloud-vhukze-api-service。

在Springcloud-vhukze-api-service下創建一個maven model，packaging選擇jar，名爲springcloud-vhukze-api-member-service。

在Springcloud-vhukze-api-service下創建一個maven model，packaging選擇jar，名爲springcloud-vhukze-api-order-service。

在Springcloud-vhukze-parent下創建一個maven model，packaging選擇jar，名爲springcloud-vhukze-member-service-impl，是springcloud-vhukze-api-member-service的實現項目。

在Springcloud-vhukze-parent下創建一個maven model，packaging選擇jar，名爲springcloud-vhukze-order-service-impl，是springcloud-vhukze-api-order-service的實現項目。

在父項目parent中引入依賴

  <parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.3.RELEASE</version>
	</parent>
	<!-- 管理依賴 -->
	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>Finchley.RELEASE</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>
	<dependencies>
		<!-- SpringBoot整合Web組件 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<!-- SpringBoot整合eureka客戶端 -->
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
		</dependency>
		<!-- SpringBoot整合fegnin客戶端 -->
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-openfeign</artifactId>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
		</dependency>

	</dependencies>
	<!-- 注意： 這裏必須要添加， 否者各種依賴有問題 -->
	<repositories>
		<repository>
			<id>spring-milestones</id>
			<name>Spring Milestones</name>
			<url>https://repo.spring.io/libs-milestone</url>
			<snapshots>
				<enabled>false</enabled>
			</snapshots>
		</repository>
	</repositories>

在springcloud-vhukze-api-member-service中創建如下兩個類

 實體類兩個屬性，name age 加getset方法重寫toString。

IMemberService類

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import com.vhukze.api.entity.UserEntity;

public interface IMemberService {

	@RequestMapping("getMember")
	public UserEntity getMember(@RequestParam("name") String name);
}

在springcloud-vhukze-member-service-impl引入springcloud-vhukze-api-member-service依賴

<dependencies>
		<dependency>
			<groupId>com.vhukze</groupId>
			<artifactId>springcloud-vhukze-api-member-service</artifactId>
			<version>0.0.1-SNAPSHOT</version>
		</dependency>
	</dependencies>

並創建如下兩個類

啓動類MemberApp

@SpringBootApplication
@ComponentScan(basePackages = "com.vhukze")
@EnableEurekaClient
@EnableFeignClients
public class MemberApp {

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

接口實現類MemberServiceImpl

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.vhukze.api.entity.UserEntity;
import com.vhukze.api.service.IMemberService;

@RestController
public class MemberServiceImpl implements IMemberService{

	@RequestMapping("/getMember")
	public UserEntity getMember(String name) {
		// TODO Auto-generated method stub
		UserEntity user = new UserEntity();
		user.setName(name);
		user.setAge(19);
		return user;
	}

}

application.yml配置文件

###服務啓動端口號
server:
  port: 8000
###服務名稱(服務註冊到eureka名稱)  
spring:
    application:
        name: app-vhuze-member
###服務註冊到eureka地址
eureka:
  client:
    service-url:
           defaultZone: http://localhost:8100/eureka

           
###因爲該應用爲註冊中心，不會註冊自己
    register-with-eureka: true
###是否需要從eureka上獲取註冊信息
    fetch-registry: true

在springcloud-vhukze-api-order-service創建如下類

import org.springframework.web.bind.annotation.RequestMapping;

public interface IOrderService {

	@RequestMapping("toMember")
	public String toMember(String name);
}

在springcloud-vhukze-order-service-impl中引入springcloud-vhukze-api-order-service和springcloud-vhukze-api-member-service依賴

  	<dependencies>
		<dependency>
			<groupId>com.vhukze</groupId>
			<artifactId>springcloud-vhukze-api-order-service</artifactId>
			<version>0.0.1-SNAPSHOT</version>
		</dependency>
		<dependency>
			<groupId>com.vhukze</groupId>
			<artifactId>springcloud-vhukze-api-member-service</artifactId>
			<version>0.0.1-SNAPSHOT</version>
		</dependency>
	</dependencies>

並創建如下類

啓動類OrderApp

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(basePackages = "com.vhukze")
@EnableEurekaClient
@EnableFeignClients(basePackages = "com.vhukze.order")
public class OrderApp {

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

接口實現類OrderServiceImpl

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.vhukze.api.entity.UserEntity;

@RestController
public class OrderServiceImpl implements IOrderService{

	@Autowired
	private MemberServiceFeign feign;
	
	@RequestMapping("toMember")
	public String toMember(String name) {
		// TODO Auto-generated method stub
		UserEntity user = feign.getMember(name);
		return user.toString();
	}

}

feign客戶端接口

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;

import com.vhukze.api.service.IMemberService;

@FeignClient("app-vhuze-member")
@Component
public interface MemberServiceFeign extends IMemberService{

	
}

只需繼承IMemberService接口即可。

application.yml配置文件

###服務啓動端口號
server:
  port: 8020
###服務名稱(服務註冊到eureka名稱)  
spring:
    application:
        name: app-vhuze-order
###服務註冊到eureka地址
eureka:
  client:
    service-url:
           defaultZone: http://localhost:8100/eureka

           
###因爲該應用爲註冊中心，不會註冊自己
    register-with-eureka: true
###是否需要從eureka上獲取註冊信息
    fetch-registry: true

啓動Eureka註冊中心

啓動OrderApp和MemberApp

訪問http://localhost:8020/toMember?name=22