spring cloud feign方式使用服务

spring cloud feign方式使用服务

feign采用的是接口加注解
feign 整合了ribbon(有提供负载均衡功能)

<?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.midea</groupId>
	<artifactId>base</artifactId>
	<version>1.0-SNAPSHOT</version>
	<packaging>jar</packaging>
	<name>base</name>

	<!-- 设定仓库,按设定顺序进行查找. -->
	<!--<repositories> <repository> <id>public</id> <name>Team Nexus Repository</name> 
		<url>http://10.33.183.113:8081/nexus/content/groups/public</url> <snapshots> 
		<enabled>true</enabled> <updatePolicy>always</updatePolicy> </snapshots> 
		</repository> </repositories> <pluginRepositories> <pluginRepository> <id>public</id> 
		<name>Team Nexus Repository</name> <url>http://10.33.183.113:8081/nexus/content/groups/public</url> 
		<snapshots> <enabled>true</enabled> <updatePolicy>always</updatePolicy> </snapshots> 
		</pluginRepository> </pluginRepositories> -->

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.2.RELEASE</version>
	</parent>
	
	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>Dalston.SR1</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>
	
	<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>

		<dependency>
			<groupId>io.springfox</groupId>
			<artifactId>springfox-swagger2</artifactId>
			<version>2.4.0</version>
			<exclusions>
				<exclusion>
					<groupId>org.slf4j</groupId>
					<artifactId>slf4j-api</artifactId>
				</exclusion>
			</exclusions>
		</dependency>

		<dependency>
			<groupId>io.springfox</groupId>
			<artifactId>springfox-swagger-ui</artifactId>
			<version>2.4.0</version>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-log4j2</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
			<exclusions>
				<exclusion>
					<groupId>org.springframework.boot</groupId>
					<artifactId>spring-boot-starter-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
			<exclusions>
				<exclusion>
					<groupId>org.springframework.boot</groupId>
					<artifactId>spring-boot-starter-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
	</dependencies>
	<build>

	</build>
</project>

server.port=8765
#logging.pattern.level=INFO

#服务器路径
server.context-path=/feign


#
#eureka.instance.hostname=localHost
#表示是否注册自身到eureka服务器，因为当前这个应用就是eureka服务器，没必要注册自身，所以这里是false。
#eureka.client.registerWithEureka=false
#fetchRegistry表示是否从eureka服务器获取注册信息，同上，这里不需要
#eureka.client.fetchRegistry=false
#设置eureka服务器所在的地址，查询服务和注册服务都需要依赖这个地址。
#eureka.client.serviceUrl.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/


eureka.client.serviceUrl.defaultZone=http\://localhost\:8761/eurekaServer/eureka/

spring.application.name=feign

package com.Service;

import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@FeignClient(value = "eureka-Client") //服务名字
public interface CallService {
    @RequestMapping(value = "/eurekaClient/Test/test",method = RequestMethod.GET)
    String callService();
}

package com.controller;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
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.RestController;

import com.Service.CallService;

import io.swagger.annotations.Api;

@Api(value = "/FeignTest", description = "测试接口", tags = "TestController")
@RequestMapping("/FeignTest")
@RestController
public class TestController {
	final static Logger logger = LogManager.getLogger(TestController.class);

	@Autowired
	CallService callService;

	@RequestMapping(value = "/test", method = RequestMethod.GET)
	public String test() {
		logger.info("test");

		// 调用服务进行远程调用
		String temp = callService.callService();

		logger.info("temp == " + temp);

		return temp;
	}
}

package com;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;



@SpringBootApplication //spring boot 开启应用
//@EnableDiscoveryClient //Discovery Service”有多种实现，比如：eureka, consul, zookeeper。
@EnableEurekaClient //只能为eureka作用
@EnableFeignClients //Feign
public class Application {

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

https://blog.csdn.net/forezp/article/details/73480304(深入理解Feign之源码解析)


https://www.jianshu.com/p/d9177fbc9c6b(@HystrixCommand的实现原理（AOP）)
HystrixCommand的构造是AOP的ProceedingJoinPoint


http://blog.51cto.com/12980017/2140699（自定义Eureka集群负载均衡策略）


https://yq.aliyun.com/articles/624145(SpringCloud(Finchley版本)中Feign与Hystrix集成的配置总结,实现原理分析)