创建一个服务消费者 ribbon+restTemplate

红太狼 2023-02-25 13:29 10阅读 0赞

## SpringCloud视频教程： ##

[https://ke.qq.com/course/2805647?tuin=a3e3fb1&from\_uin=171851697&from=1000201007][https_ke.qq.com_course_2805647_tuin_a3e3fb1_from_uin_171851697_from_1000201007]

## **个人博客纯净版** ##

[http://www.51ufo.cn/%E5%BE%AE%E6%9C%8D%E5%8A%A1/%E5%88%86%E5%B8%83%E5%BC%8F/2020/07/10/SpringCloud%E5%85%A5%E9%97%A84-%E5%88%9B%E5%BB%BA%E4%B8%80%E4%B8%AA%E6%9C%8D%E5%8A%A1%E6%B6%88%E8%B4%B9%E8%80%85-ribbon+restTemplate.html][http_www.51ufo.cn_E5_BE_AE_E6_9C_8D_E5_8A_A1_E5_88_86_E5_B8_83_E5_BC_8F_2020_07_10_SpringCloud_E5_85_A5_E9_97_A84-_E5_88_9B_E5_BB_BA_E4_B8_80_E4_B8_AA_E6_9C_8D_E5_8A_A1_E6_B6_88_E8_B4_B9_E8_80_85-ribbon_restTemplate.html]

本文代码git地址 [https://gitee.com/xmingtx/springcloud-lesson.git][https_gitee.com_xmingtx_springcloud-lesson.git]

在前面，讲了服务的注册和发现。在微服务架构中，业务都会被拆分成一个独立的服务，服务与服务的通讯是基于http restful的。Spring cloud有两种服务调用方式，一种是ribbon+restTemplate，另一种是feign。现在我们首先讲解下基于ribbon+restTemplate。

首先我们在父模块下创建一个子模块，名称为consumer-ribbon，pom.xml依赖如下：

<dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
        </dependency>
    </dependencies>

在resources目录下创建application.yml配置文件，配置如下：

server:
      port: 8090
    
    spring:
      application:
        name: consumer-ribbon
    
    eureka:
      client:
        serviceUrl:
          defaultZone: http://localhost:8761/eureka/
      instance:
        prefer-ip-address: true
        instance-id: ${spring.cloud.client.ip-address}:${server.port}

然后创建一个启动类，通过注解@EnableEurekaClient 表明自己是一个eurekaclient，代码如下：

@EnableEurekaClient
    @SpringBootApplication
    public class ConsumerApplication {
        public static void main(String[] args) {
            SpringApplication.run(ConsumerApplication.class);
        }
        @Bean
        public RestTemplate restTemplate() {
            return new RestTemplate();
        }
    }

创建HelloControler，代码如下：

@RestController
    public class HelloController {
    
        @Autowired
        private DiscoveryClient discoveryClient;
    
        @Autowired
        private RestTemplate restTemplate;
    
        @GetMapping(value = "/hello")
        public String hello(@RequestParam String name) {
            List<ServiceInstance> instances = discoveryClient.getInstances("eureka-client-provider");
            ServiceInstance instance = instances.get(0);
            return restTemplate.getForObject(instance.getUri() + "/hello?name=" + name, String.class);
        }
    }

启动服务，eureka注册中心又多了一个服务，如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoYW9qdW5tYQ_size_16_color_FFFFFF_t_70][]

在浏览器访问[http://localhost:8090/hello?name=xiaoming][http_localhost_8090_hello_name_xiaoming]，返回结果如下：

hello, xiaoming, 我是服务提供者:端口为：8080

说明通过消费者调用服务提供者的服务调用成功了

[https_ke.qq.com_course_2805647_tuin_a3e3fb1_from_uin_171851697_from_1000201007]: https://ke.qq.com/course/2805647?tuin=a3e3fb1&from_uin=171851697&from=1000201007
[http_www.51ufo.cn_E5_BE_AE_E6_9C_8D_E5_8A_A1_E5_88_86_E5_B8_83_E5_BC_8F_2020_07_10_SpringCloud_E5_85_A5_E9_97_A84-_E5_88_9B_E5_BB_BA_E4_B8_80_E4_B8_AA_E6_9C_8D_E5_8A_A1_E6_B6_88_E8_B4_B9_E8_80_85-ribbon_restTemplate.html]: http://www.51ufo.cn/%E5%BE%AE%E6%9C%8D%E5%8A%A1/%E5%88%86%E5%B8%83%E5%BC%8F/2020/07/10/SpringCloud%E5%85%A5%E9%97%A84-%E5%88%9B%E5%BB%BA%E4%B8%80%E4%B8%AA%E6%9C%8D%E5%8A%A1%E6%B6%88%E8%B4%B9%E8%80%85-ribbon+restTemplate.html
[https_gitee.com_xmingtx_springcloud-lesson.git]: https://gitee.com/xmingtx/springcloud-lesson.git
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoYW9qdW5tYQ_size_16_color_FFFFFF_t_70]: /images/20230209/7234d1843c954740899ed8b6d7b664f6.png
[http_localhost_8090_hello_name_xiaoming]: http://localhost:8090/hello?name=xiaoming