SpringCloud（三）服务提供与调用

• 搭建一个简单的服务端注册服务，客户端去调用服务使用的案例。
• 三种角色：服务注册中心、服务提供者、服务消费者
• 首先启动注册中心，服务提供方着生产服务并注册到服务中心中，消费者从服务中心中获取服务并执行

服务提供方

1.pom.xml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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.bigdog</groupId>
	<artifactId>springcloud_eureka_consumer</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>springcloud_eureka_consumer</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>
	</properties>

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

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

		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-eureka</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-feign</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>
	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>Dalston.SR1</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.配置文件 application.properties

spring.application.name=springcloud-eureka-consumer
server.port=3001
eureka.client.serviceUrl.defaultZone=http://localhost:1001/eureka/

3.启动类

package com.bigdog;

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

/**
 * 消费者
 * @author Administrator
 *
 */
@SpringBootApplication
// 启用服务注册与发现
@EnableDiscoveryClient
// 启用feign进行远程调用
// Feign是一个声明式Web Service客户端。使用Feign能让编写Web Service客户端更加简单,
// 它的使用方法是定义一个接口，然后在上面添加注解，同时也支持JAX-RS标准的注解。Feign也支持可拔插式的编码器和解码器。
// SpringCloud对Feign进行了封装，使其支持了Spring
// MVC标准注解和HttpMessageConverters。Feign可以与Eureka和Ribbon组合使用以支持负载均衡。
@EnableFeignClients
public class EurekaConsumerApplication {

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

4.feign调用实现

//name远程服务名，即spring.application.name=springcloud-eureka-client
@FeignClient(name = "springcloud-eureka-client")
public interface HelloRemote {

	@RequestMapping(value = "/hello")
	public  String hello(@RequestParam(value = "name") String name);
}

5.Web层调用远程服务

@RestController
public class ConsumerController {

	@Autowired
	private HelloRemote helloRemote;
	
	@RequestMapping("/hello/{name}")
    public String index(@PathVariable("name") String name) {
        return helloRemote.hello(name);
    }
}

测试

1.依次启动spring-cloud-eureka、spring-cloud-producer、spring-cloud-consumer三个项目

2.输入++http://127.0.0.1:3001/hello/curry++
返回结果 ：hello currythis is a first message

代码示例