SpringCloud的学习-Feign服务消费者（3）

Feign
Feign 采用的是基于接口的注解
Feign 整合了ribbon，具有负载均衡的能力
整合了Hystrix，具有熔断的能力
准备工作
启动Server端，及Client端，参考上文。
创建SpringBoot项目，名称Feign。
Pom文件
配置Pom文件，代码如下

<?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>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.2.RELEASE</version>
    </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.cloud</groupId>
            <artifactId>spring-cloud-starter-feign</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.RC1</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>

    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>


</project>

注意自己的项目名称，不要和我的Pom一样。
配置application.yml

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
server:
  port: 8772
spring:
  application:
    name: service-feign

添加注解
@EnableDiscoveryClient
@EnableFeignClients //开启Feign功能
代码如下

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class DemoApplication {

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

}

写接口
创建接口
写一个Feign接口，通过@ FeignClient（“服务名”），来选择调用的服务。

@FeignClient("service-hc")
public interface SchedualServiceHi {
    @RequestMapping(value = "/hi",method = RequestMethod.GET)
    String sayHiFromClientOne(@RequestParam(value = "name") String name);
}

写Controller
定义一个"/hi"的API接口，通过上面定义的Feign客户端SchedualServiceHi 来消费服务

@RestController
public class HiController {
    @Autowired
    SchedualServiceHi schedualServiceHi;
    @GetMapping(value = "/hi")
    public String sayHi(@RequestParam String name) {
        return schedualServiceHi.sayHiFromClientOne( name );
    }
}

启动，并访问启动程序，多次访问http://localhost:8772/hi?name=happy,浏览器交替显示：

hi happy,i am from port:8771
hi happy,i am from port:8772

参考文章 https://blog.youkuaiyun.com/forezp/article/details/81040965 其实我都是跟着这个博主在做，这只是我自己的一个记录过程，遇到的一些小问题，都有所修改，才最后达到了预期的效果。