Feign是一个声明式WebService客户端。 使用Feign能让编写Web Service客户端更加简单。 它的使用方法是定义一个服务接口然后在上面添加注解。 Feign也支持可拔插式的编码器和解码器。 Spring Cloud对Feign进行了封装,使其支持了Spring MVC标准注解和HttpMessageConverters。 Feign可以与Eureka和Ribbon组合使用以支持负载均衡
Feign | OpenFeign |
---|---|
Feign是Spring Cloud组件中的一个轻量级RESTful的HTTP服务客户端Feign内置了Ribbon,用来做客户端负载均衡,去调用服务注册中心的服务。Feign的使用方式是:使用Feign的注解定义接口,调用这个接口,就可以调用服务注册中心的服务 | OpenFeign是Spring Cloud 在Feign的基础上支持了SpringMVC的注解,如@RequesMapping等等。OpenFeign的@FeignClient可以解析SpringMVC的@RequestMapping注解下的接口,并通过动态代理的方式产生实现类,实现类中做负载均衡并调用其他服务。 |
<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-feign</artifactId></dependency> | <dependency><groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId></dependency> |
<?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">
<parent>
<artifactId>cloud2023</artifactId>
<groupId>top.ljzstudy.springcloud</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>cloud-consumer-feign-order80</artifactId>
<dependencies>
<!--openfeign-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<!--eureka client-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<!-- 引入自己定义的api通用包,可以使用Payment支付Entity -->
<dependency>
<groupId>top.ljzstudy.springcloud</groupId>
<artifactId>cloud-api-commons</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<!--web-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<!--一般基础通用配置-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<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>
</project>
server:
port: 80
eureka:
client:
register-with-eureka: false
service-url:
defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/
package top.ljzstudy.springcloud;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication
@EnableFeignClients//开启OpenFeginClient
public class OrderFeignMain80 {
public static void main(String[] args) {
SpringApplication.run(OrderFeignMain80.class,args);
}
}
package top.ljzstudy.springcloud.service;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import top.ljzstudy.springcloud.entities.CommonResult;
import top.ljzstudy.springcloud.entities.PaymentEntity;
@Component
@FeignClient("CLOUD-PAYMENT-SERVICE")//主启动类必须开启EnableFeginClients
public interface FeignPaymentService {
@GetMapping("/payment/get/{id}")
CommonResult<PaymentEntity> getPaymentEntityById(@PathVariable("id") Long id);
}
package top.ljzstudy.springcloud.controller;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import top.ljzstudy.springcloud.entities.CommonResult;
import top.ljzstudy.springcloud.entities.PaymentEntity;
import top.ljzstudy.springcloud.service.FeignPaymentService;
import javax.annotation.Resource;
@RestController
@Slf4j
public class FeignPaymentController {
@Resource
private FeignPaymentService feignPaymentService;
@GetMapping("/consumer/payment/getEntity/{id}")
public CommonResult<PaymentEntity> getPaymentEntity(@PathVariable("id") Long id){
return feignPaymentService.getPaymentEntityById(id);
}
}
GET http://localhost:80/consumer/payment/getEntity/1
HTTP/1.1 200
Content-Type: application/json
Transfer-Encoding: chunked
Date: Thu, 14 Sep 2023 17:21:33 GMT
Keep-Alive: timeout=60
Connection: keep-alive
{
"code": 200,
"message": "successful query data to id =1 from port number : 8001",
"data": {
"id": 1,
"serial": "ljzTest01"
}
}
Response code: 200; Time: 1031ms; Content length: 116 bytes
场景模拟,服务端完成一个业务所需时间假定为3sec,客户端最多等待时间为2sec.必然产生矛盾
package top.ljzstudy.springcloud.controller;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.*;
import top.ljzstudy.springcloud.entities.CommonResult;
import top.ljzstudy.springcloud.entities.PaymentEntity;
import top.ljzstudy.springcloud.service.PaymentService;
import javax.annotation.Resource;
import java.util.List;
import java.util.concurrent.TimeUnit;
@RestController
@Slf4j
public class PaymentController {
@Value("${server.port}")
private String serverPort;
....
/**
* OpenFeigin超时控制
* 业务场景-->服务提供者业务逻辑处理完成需要3min,客户端需求2min,存在时间差
* 时间差导致超时调用报错,此处采用睡眠模拟延时
*/
@GetMapping("/payment/feign/timeout")
public String paymentFeignTimeout(){
System.out.println("*****paymentFeignTimeOut from port: "+serverPort);
//暂停几秒钟线程
try {
TimeUnit.SECONDS.sleep(3);
} catch (InterruptedException e) {
e.printStackTrace();
}
return serverPort;
}
......
}
package top.ljzstudy.springcloud.service;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import top.ljzstudy.springcloud.entities.CommonResult;
import top.ljzstudy.springcloud.entities.PaymentEntity;
@Component
@FeignClient("CLOUD-PAYMENT-SERVICE")
public interface FeignPaymentService {
//模拟业务场景接口
@GetMapping("/payment/feign/timeout")
String paymentFeignTimeout();
}
package top.ljzstudy.springcloud.controller;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import top.ljzstudy.springcloud.entities.CommonResult;
import top.ljzstudy.springcloud.entities.PaymentEntity;
import top.ljzstudy.springcloud.service.FeignPaymentService;
import javax.annotation.Resource;
@RestController
@Slf4j
public class FeignPaymentController {
@Resource
private FeignPaymentService feignPaymentService;
//模拟业务方法
@GetMapping("/consumer/payment/feign/timeout")
public String paymentFeignTimeout(){
//openfeign-ribbon 客户端一般默认等待1秒
return feignPaymentService.paymentFeignTimeout();
}
}
GET http://localhost/consumer/payment/feign/timeout
HTTP/1.1 500
Content-Type: application/json
Transfer-Encoding: chunked
Date: Thu, 14 Sep 2023 17:37:35 GMT
Connection: close
{
"timestamp": "2023-09-14T17:37:35.924+0000",
"status": 500,
"error": "Internal Server Error",
"message": "status 404 reading FeignPaymentService#paymentFeignTimeout()",
/*
* 提示:该行代码过长,系统自动注释不进行高亮。一键复制会移除系统注释
* "trace": "feign.FeignException$NotFound: status 404 reading FeignPaymentService#paymentFeignTimeout()\r\n\tat feign.FeignException.clientErrorStatus(FeignException.java:165)\r\n\tat feign.FeignException.errorStatus(FeignException.java:141)\r\n\tat feign.FeignException.errorStatus(FeignException.java:133)\r\n\tat feign.codec.ErrorDecoder$Default.decode(ErrorDecoder.java:92)\r\n\tat feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:151)\r\n\tat feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:80)\r\n\tat feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:103)\r\n\tat com.sun.proxy.$Proxy149.paymentFeignTimeout(Unknown Source)\r\n\tat top.ljzstudy.springcloud.controller.FeignPaymentController.paymentFeignTimeout(FeignPaymentController.java:27)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\r\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\r\n\tat java.lang.reflect.Method.invoke(Method.java:498)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)\r\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)\r\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)\r\n\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:634)\r\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:741)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:108)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)\r\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)\r\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:526)\r\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)\r\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\r\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)\r\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)\r\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)\r\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)\r\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:860)\r\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1591)\r\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\r\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)\r\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)\r\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\r\n\tat java.lang.Thread.run(Thread.java:748)\r\n",
*/
"path": "/consumer/payment/feign/timeout"
}
Response code: 500; Time: 281ms; Content length: 6283 bytes
#设置feign客户端超时时间
feign:
client:
config:
default:
connect-timeout: 5000 #指的是建立连接所用的时间,适用于网络状况正常的情况下,两端连接所用的时间
read-timeout: 5000 #指的是建立连接后从服务器读取到可用资源所用的时间
是什么?
package top.ljzstudy.springcloud.config;
import feign.Logger;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class FeignConfig {
@Bean
Logger.Level feignLoggerLevel(){
return Logger.Level.FULL;
}
}
logging:
level:
# feign日志以什么级别监控哪个接口
top.ljzstudy.springcloud.service.FeignPaymentService: debug