Shulou(Shulou.com)06/02 Report--

Spring Cloud how to remotely call Feign and integrate Load Balancer Ribbon Fuse Hystrix), for this problem, this article introduces the corresponding analysis and solution in detail, hoping to help more small partners who want to solve this problem find a simpler and easier way.

What is Feign?

Feign is a member of the spring cloud family bucket for remote invocation.

Features: Declarative, templated HTTP client. Make remote calls feel like "local methods" when used

Feign entry

Step 1: Modify pom file and add Feign dependency

Step 2: Modify the startup class and add the Open Feign annotation

Step 3: Write Feign interface, complete remote call, replace dao layer

Step 4: Modify controller to change dao to feign

Step 1: Modify the pom file and add Feign dependencies

org.springframework.cloud spring-cloud-starter-openfeign

Step 2: Modify the startup class and add the Open Feign annotation

import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.netflix.eureka.EnableEurekaClient;import org.springframework.cloud.netflix.hystrix.EnableHystrix;import org.springframework.cloud.openfeign.EnableFeignClients;@SpringBootApplication@EnableEurekaClient@EnableHystrix //Open fuses @ EnableFeigClients//Open FeigClients public class Client4Application {public static void main(String[] args) { SpringApplication.run(Client4Application.class,args);}}

Step 3: Write Feign interface, complete remote call, replace dao layer

@FeignClient(value="service name",path="controller prefix")public interface interface name { //Same as controller method}

package com.czxy.feign;import org.springframework.cloud.openfeign.FeignClient;import org.springframework.http.ResponseEntity;import org.springframework.web.bind.annotation.GetMapping;import javax.servlet.http.HttpServletRequest;@FeignClient(value="service4",path="/test")public interface DataFeign { @GetMapping public ResponseEntity test() ;}

Step 4: Modify controller to change dao to feign

package com.czxy.controller;import com.czxy.dao.DataDao;import com.czxy.feign.DataFeign;import org.springframework.http.ResponseEntity;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;@RestController@RequestMapping("/data")public class DataController { @Resource //private DataDao dataDao; private DataFeign dataFeign; @GetMapping public ResponseEntity data(){ //return dataDao.data(); return dataFeign.test(); }}Feign Integration Load Balancer Ribbon

Spring Cloud completes remote invocation and Load Balancer

Option 1: Use RestTemplate and add the extra annotation @LoadBalanced

Approach 2: Using Feign, Integrated Ribbon, Automatic Load Balancer

If you need to configure ribbon for service separately, please refer to (optional)

#Load Balancer Policy Configuration service4: ribbon: #NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule #Random #NFLoadBalancerRuleClassName : com.netflix.loadbalancer.BestAvailableRule #Concurrence is minimal NFLoadBalancerRuleClassName : com.netflix.loadbalancer.WeightedResponseTimeRule #Request Time Weights ConnectTimeout: 250 # Ribbon connection timeout ReadTimeout: 1000 # Ribbon data read timeout OkToRetryOnAllOperations: true #Retry all operations MaxAutoRetriesNextServer: 1 #Number of retries to switch instances MaxAutoRetries: 1 #Retries for current instance Feign integrated fuse Hystrix

Step 1: Modify the yml file and turn on the feign fuse mechanism

Step 2: Create feign interface implementation class and provide alternatives

Step 3: invoke feign, specify fallback to determine alternative

Step 1: Modify the yml file and turn on the feign fuse mechanism

feign: hystrix: enabled: true #Turn on feign fuse

Step 2: Create feign interface implementation class and provide alternatives

package com.czxy.feign;import org.springframework.http.ResponseEntity;import org.springframework.stereotype.Component;@Componentpublic class DataFeignFallback implements DataFeign { @Override public ResponseEntity test() { return ResponseEntity.ok("feign alternative"); }}

Step 3: invoke feign, specify fallback to determine alternative

@ FeinClient (value="service name," path="prefix path," fallback= alternative class.class)public interface Interface Name {package com.czxy.feign;import org.springframework.cloud.openfeign. FeinClient;import org.springframework.http.ResponseEntity;import org. springframework.web.bind.annotation.GetMapping;import javax.servlet.http. ServletRequest; @ FeinClient (value="service4," path="/test," fallback= DataFeinFallback.class)public interface DataFeign { @GetMapping public ResponseEntity test() ;} About Spring Cloud how to remotely call Feign and integrate Load Balancer Ribbon Fuse Hystrix) The answer to the question is shared here. I hope the above content can be of some help to everyone. If you still have a lot of doubts, you can pay attention to the industry information channel for more relevant knowledge.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.