springcloud+eureka+feign负载均衡

谁借莪１个温暖的怀抱￠ 2022-03-30 09:26 289阅读 0赞

目前，在Spring cloud 中服务之间通过restful方式调用有两种方式

*  restTemplate+Ribbon
 *  feign  
    现在咱们采用feign进行负载均衡，他的好处就是可以实现接口式的负载均衡，符合接口式的开发规范，而不是像ribbon，要结合restTemplate，通过Feign直接找到服务接口，由于在进行服务调用的时候融合了Ribbon技术，所以也支持负载均衡作用。

服务如下：  
注意这里没有的dept-80服务，它被dept-feign服务代替。  
![在这里插入图片描述][20190105160910731.png]

## 1 microservicecloud-api ##

它主要为其他服务提供实体类和接口服务，打成，写成后打成jar即可  
我们也可以将feign服务接口写在dept-feign服务里面，但是这些接口可能会被其他服务所调用，所以建议写在api中。  
![在这里插入图片描述][20190105162557957.png]  
pom.xml

DeptClientService.java

package com.wuk.service;
    
    import java.util.List;
    
    import org.springframework.cloud.netflix.feign.FeignClient;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    
    import com.wuk.entity.Dept;
    
    @FeignClient(value = "producers")
    public interface DeptClientService { 
    
    	@RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
    	public Dept get(@PathVariable("id") long id);
    
    	@RequestMapping(value = "/dept/list", method = RequestMethod.GET)
    	public List<Dept> list();
    
    	@RequestMapping(value = "/dept/add", method = RequestMethod.POST)
    	public boolean add(Dept dept);
    
    }

然后将其打成jar，引入到其他服务中。

## 2 microservicecloud-consumer-dept-feign ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3d1MjM3NDYzMzU4Mw_size_16_color_FFFFFF_t_70]  
pom.xml

<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>
    	<parent>
    		<groupId>com.wuk.springcloud</groupId>
    		<artifactId>microservicecloud</artifactId>
    		<version>0.0.1-SNAPSHOT</version>
    	</parent>
    	<artifactId>microservicecloud-consumer-dept-feign</artifactId>
    	<dependencies>
    		<dependency>
    			<groupId>com.wuk.springcloud</groupId>
    			<artifactId>microservicecloud-api</artifactId>
    			<version>${project.version}</version>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-web</artifactId>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>springloaded</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-devtools</artifactId>
    		</dependency>
    
    		<dependency>
    			<groupId>org.springframework.cloud</groupId>
    			<artifactId>spring-cloud-starter-eureka</artifactId>
    		</dependency>
    
    		<dependency>
    			<groupId>org.springframework.cloud</groupId>
    			<artifactId>spring-cloud-starter-config</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.cloud</groupId>
    			<artifactId>spring-cloud-starter-feign</artifactId>
    		</dependency>
    
    	</dependencies>
    </project>

application.yml

server:
      port: 80
      
    eureka:
      client:
        register-with-eureka: false
        service-url: 
          defaultZone: http://127.0.0.1:7001/eureka/

DeptController\_Consumer.java

package com.wuk.controller;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import com.wuk.entity.Dept;
    import com.wuk.service.DeptClientService;
    
    @RestController
    public class DeptController_Consumer { 
    	
    	@Autowired
    	private DeptClientService service = null;
    
    
    	@RequestMapping(value = "/consumer/dept/add")
    	public boolean add(Dept dept) { 
    		return service.add(dept);
    	}
    	
    	@RequestMapping(value = "/consumer/dept/get/{id}")
    	public Dept get(@PathVariable("id") Long id) { 
    		return service.get(id);
    	}
    
    	@SuppressWarnings("unchecked")
    	@RequestMapping(value = "/consumer/dept/list")
    	public List<Dept> list() { 
    		return service.list();
    	}
    }

DeptConsumer80\_Feign\_App.java

package com.wuk;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
    import org.springframework.cloud.netflix.feign.EnableFeignClients;
    import org.springframework.context.annotation.ComponentScan;
    
    @SpringBootApplication
    @EnableEurekaClient
    @EnableFeignClients(basePackages= { "com.wuk"})
    @ComponentScan("com.wuk")
    public class DeptConsumer80_Feign_App { 
    
    	public static void main(String[] args) { 
    		
    		SpringApplication.run(DeptConsumer80_Feign_App.class, args);
    	}
    }

剩下的两个服务方和服务注册中心上一篇有，不做赘述。

[20190105160910731.png]: /images/20220330/902aa1bb6ada4dbdb4ffacbbe4288879.png
[20190105162557957.png]: /images/20220330/47a1b0fa84da4f19a111c80753530f99.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3d1MjM3NDYzMzU4Mw_size_16_color_FFFFFF_t_70]: /images/20220330/26def90290214009b1e4c975c9f11cc2.png