Spring Cloud 服务的提供者与消费者（rest+ribbon）

服务消费者（rest+ribbon）

一、ribbon简介

ribbon是一个负载均衡客户端，可以很好的控制htt和tcp的一些行为。Feign默认集成了ribbon。

ribbon 已经默认实现了这些配置bean：

• IClientConfig ribbonClientConfig: DefaultClientConfigImpl
• IRule ribbonRule: ZoneAvoidanceRule
• IPing ribbonPing: NoOpPing
• ServerList ribbonServerList: ConfigurationBasedServerList
• ServerListFilter ribbonServerListFilter: ZonePreferenceServerListFilter
• ILoadBalancer ribbonLoadBalancer: ZoneAwareLoadBalancer

在工程的启动类中,通过@EnableDiscoveryClient向服务中心注册；并且向程序的ioc注入一个bean: restTemplate;并通过@LoadBalanced注解表明这个restRemplate开启负载均衡的功能。

import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.client.discovery.EnableDiscoveryClient;import org.springframework.cloud.client.loadbalancer.LoadBalanced;import org.springframework.context.annotation.Bean;import org.springframework.web.client.RestTemplate;@SpringBootApplication@EnableDiscoveryClientpublic class ConsumerRibbonApplication {public static void main(String[] args) {SpringApplication.run(ConsumerRibbonApplication.class, args);}@Bean@LoadBalancedRestTemplate restTemplate() {return new RestTemplate();}}

Service层（严格遵循MVC的思想）：

import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import org.springframework.web.client.RestTemplate;/*** @Author:chenyiwu* @Describtion:* @Create Time:2018/6/19*/@Servicepublic class PersonService {@Autowiredprivate RestTemplate restTemplate;public String hiService(String name) {return restTemplate.getForObject("http://SERVICE-HI/hi?name=" + name, String.class);}}

编写一个Controller：

import com.saliai.service.PersonService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.bind.annotation.RestController;/*** @Author:chenyiwu* @Describtion:* @Create Time:2018/6/19*/@RestControllerpublic class PersonController {@Autowiredprivate PersonService personService;@RequestMapping(value = "/getHiService", method = RequestMethod.GET)public String sayHiService(@RequestParam(value = "name") String name) {return personService.hiService(name);}}