2.Feign基本demo

1. pom

<?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">
    <parent>
        <artifactId>spring-cloud-demo</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../../pom.xml</relativePath>
    </parent>
<modelVersion>4.0.0</modelVersion>

<artifactId>feign-consumer</artifactId>
<packaging>jar</packaging>
<name>feign-consumer</name>
    <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.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

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


</project>

2. FeignConsumerApplication 启动类

package com.imooc.springcloud;

import org.springframework.boot.WebApplicationType;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;

/**
 * Created by 半仙.
 */
@EnableDiscoveryClient
@SpringBootApplication
@EnableFeignClients
public class FeignConsumerApplication {

    public static void main(String[] args) {
        new SpringApplicationBuilder(FeignConsumerApplication.class)
                .web(WebApplicationType.SERVLET)
                .run(args);
    }

}

3. IService接口类

通过这个类来发起远程调用

• @FeignClient("eureka-client")
• @GetMapping("/sayHi")

package com.imooc.springcloud;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;

/**
 * Created by 半仙.
 */
@FeignClient("eureka-client")
public interface IService {

    @GetMapping("/sayHi")
    String sayHi();

}

4. Controller类

package com.imooc.springcloud;

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

/**
 * Created by 半仙.
 */
@RestController
public class Controller {

    @Autowired
    private IService service;

    @GetMapping("/sayHi")
    public String sayHi() {
        return service.sayHi();
    }

}

5. application.properties配置文件

spring.application.name=feign-consumer
server.port=40001

eureka.client.serviceUrl.defaultZone=http://localhost:20000/eureka/

# 每台机器最大重试次数
feign-client.ribbon.MaxAutoRetries=2
# 可以再重试几台机器
feign-client.ribbon.MaxAutoRetriesNextServer=2
# 连接超时
feign-client.ribbon.ConnectTimeout=1000
# 业务处理超时
feign-client.ribbon.ReadTimeout=2000
# 在所有HTTP Method进行重试
feign-client.ribbon.OkToRetryOnAllOperations=true