Feign

而Feign则会完全代理HTTP请求，我们只需要像调用方法一样调用它就可以完成服务请求及相关处理。Feign整合了Ribbon和Hystrix，可以让我们不再需要显式地使用这两个组件。

Feign具有如下特性：

支持可插拔的HTTP编码器和解码器;

支持Hystrix和它的Fallback;

支持Ribbon的负载均衡;

支持HTTP请求和响应的压缩。

有点像我们springmvc模式的Controller层的RequestMapping映射。这Feign是用@FeignClient来映射服务的。

创建一个项目

<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId><version>2.2.7.RELEASE</version></dependency><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>4.0.1</version><scope>provided</scope></dependency><!--eureka-server--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-server</artifactId><version>2.2.1.RELEASE</version></dependency><dependency><!-- 引入自己定义的api通用包，可以使用Payment支付Entity --><groupId>com</groupId><artifactId>cloud-api-commons</artifactId><version>0.0.1-SNAPSHOT</version></dependency>

总依赖：

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.2.2.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com</groupId><artifactId>springcloud</artifactId><version>0.0.1-SNAPSHOT</version><name>cloud-consumer-feign-order80</name><description>cloud-consumer-feign-order80</description><properties><java.version>1.8</java.version></properties><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId><version>2.2.7.RELEASE</version></dependency><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>4.0.1</version><scope>provided</scope></dependency><!--eureka-server--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-server</artifactId><version>2.2.1.RELEASE</version></dependency><dependency><!-- 引入自己定义的api通用包，可以使用Payment支付Entity --><groupId>com</groupId><artifactId>cloud-api-commons</artifactId><version>0.0.1-SNAPSHOT</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-devtools</artifactId><scope>runtime</scope><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-configuration-processor</artifactId><optional>true</optional></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies><build><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><version>3.8.1</version><configuration><source>1.8</source><target>1.8</target><encoding>UTF-8</encoding></configuration></plugin><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

application.yml

server:port: 80eureka:client:register-with-eureka: falseservice-url:defaultZone: http://localhost:7001/eureka,http://localhost:7002/eureka

运行项目，可以成功访问到。

先启动7001与7002，再启动8001，8002，最后再启动80.

OpenFign日志增强

FeignConfig

package com.springcloud.config;import feign.Logger;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** @auther zzyy* @create 2020-02-20 9:40*/
@Configuration
public class FeignConfig
{@BeanLogger.Level feignLoggerLevel(){return Logger.Level.FULL;}
}

server:port: 80eureka:client:register-with-eureka: falseservice-url:defaultZone: http://localhost:7001/eureka,http://localhost:7002/eurekalogging:level:# feign日志以什么级别监控哪个接口com.springcloud.service.PaymentService: debug

运行项目。

控制台：