第四章:spring cloud分布式开发之openfeign
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2022-04-07 12:34:18
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Spring Cloud中的openfeign整合了ribbon的负载均衡和熔断机制,还实现了微服务之间的相互调用
这章我们主要讲解openfeign实现一个feign客户端调用主客户端的接口
首先我们在原有项目基础上新建一个子项目moudule
起名为sc-feign
pom文件内容为:
<?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>com.softA</groupId>
<artifactId>springcloud-demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<groupId>com.systop</groupId>
<artifactId>sc-feign</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>sc-feign</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Hoxton.SR3</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<version>2.2.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
<version>2.2.2.RELEASE</version>
</dependency>
</dependencies>
</project>
在application.yml文件中配置feign客户端的应用名称及端口
spring:
application:
name: sc-feign
server:
port: 9001
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka/
在启动类ScFeignApplcation上添加注解@EnableDiscoveryClient,@EnableFeignClients
package com;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.cloud.openfeign.FeignClient;
@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class ScFeignApplication {
public static void main(String[] args) {
SpringApplication.run(ScFeignApplication.class, args);
}
}
在scfeign路径下新建两个包controller,service
在service包内新建一个接口类
package com.systop.scfeign.service;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
/**
*
* @FeignClient
* 注解定义要调用那个微服务的名称(spring.application.name:)
*/
@FeignClient(name="sc-client")
public interface FeignClientService {
/**
*
* 定义要调用服务的哪个接口
* 使用@RequestMapping()
*
*/
@RequestMapping(value = "/add",method = RequestMethod.GET)
public String addStu(@RequestParam("name") String name, @RequestParam("age") int age, @RequestParam("height") double height, @RequestParam("love") String love);
}
在controller包内新建一个类
package com.systop.scfeign.controller;
import com.systop.scfeign.service.FeignClientService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
@RestController
public class FeignController {
@Autowired
private FeignClientService feignClientService;
@RequestMapping(value = "/add",method = RequestMethod.GET)
public String addStu(@RequestParam("name") String name, @RequestParam("age") int age, @RequestParam("height") double height, @RequestParam("love") String love){
return feignClientService.addStu(name, age, height, love);
}
}
欧克!
依次启动注册中心,主客户端,feign客户端
访问
http://localhost:9001/add?name=xiaoma&&age=23&&height=2&&love=打篮球
看到结果:
说明我们的feign客户端成功调用了主客户端的 add接口
查看数据库,数据添加成功