spring cloud feign 熔断hystrix

关注

原创最新推荐文章于 2026-07-02 09:46:28 发布 2.2k 阅读 AI 写同款· GEO 优化 ›

springcloud实战：服务间通信OpenFeign熔断 Spring Cloud OpenFeign熔断前面讲述了服务之间的相互通信，通过注解的形式，OpenFeign 的声明式HTTP客户端很容易做到不同服务之间的相互调用。我们的服务最终会部署在服务器上，由于各种原因，服务难免会发生故障，这时其他服务将无法调用故障服务，可能会一直卡在那里，导致用户体验差。针对这个问题，我们需要对服务接口进行错误处理,一旦发现无法访问,立即返回并报错,即捕捉到异常后立刻以可读化的字符串的形式返回到前端。基于以上问题，业界提出了熔断器模型。在Spring C. 阅读详情

熔断是为了避免雪崩现象。

eureka-server和eureka-provider就不在赘述。

consumer项目pom

<?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>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.3.4.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.sdgtt.com</groupId>
	<artifactId>feign-consumer</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>feign-consumer</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
		<spring-cloud.version>Hoxton.SR8</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>
		</dependency>
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-openfeign</artifactId>
		</dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
		<dependency>
            <!--            监控-->
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-actuator</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
			<exclusions>
				<exclusion>
					<groupId>org.junit.vintage</groupId>
					<artifactId>junit-vintage-engine</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>1.16.6</version>
		</dependency>
	</dependencies>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>${spring-cloud.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

consumer项目，配置文件如下：

server:
  port: 8081
spring:
  application:
    name: feign-consume
eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:12346/eureka/


feign:
  hystrix:
    enabled: true

hystrix:
    command:
      default:
        execution:
          timeout:
            enabled: true
          isolation:
            thread:
              timeoutInMilliseconds: 20000 #hystrix超时熔断时间，进行短路。

ribbon:
    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RoundRobinRule #配置规则 轮询
    ConnectTimeout: 1000 #请求连接超时时间
    ReadTimeout: 10000 #请求处理的超时时间
    OkToRetryOnAllOperations: true #对所有请求都进行重试 false：所有get重试，true：get，post都会重试
    MaxAutoRetriesNextServer: 1 #切换实例的重试次数,不包括首次调用
    MaxAutoRetries: 2 #同一台实例最大重试次数,不包括首次调用

启动类

package com.sdgtt.com.feignconsumer;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.hystrix.EnableHystrix;
import org.springframework.cloud.openfeign.EnableFeignClients;

@EnableDiscoveryClient
@EnableFeignClients
@EnableEurekaClient
@EnableHystrix
@SpringBootApplication
public class FeignConsumerApplication {

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

}

访问:http://localhost:8081/feign/test/hello

当路由到provider2时，返回正常，请求到provider1时抛出异常

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is com.netflix.hystrix.exception.HystrixRuntimeException: ServiceFeignClientInterface#consumer() timed-out and no fallback available.] with root cause

java.util.concurrent.TimeoutException: null
	at com.netflix.hystrix.AbstractCommand.handleTimeoutViaFallback(AbstractCommand.java:997) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.AbstractCommand.access$500(AbstractCommand.java:60) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.AbstractCommand$12.call(AbstractCommand.java:609) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.AbstractCommand$12.call(AbstractCommand.java:601) ~[hystrix-core-1.5.18.jar:1.5.18]
	at rx.internal.operators.OperatorOnErrorResumeNextViaFunction$4.onError(OperatorOnErrorResumeNextViaFunction.java:140) ~[rxjava-1.3.8.jar:1.3.8]
	at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) ~[rxjava-1.3.8.jar:1.3.8]
	at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) ~[rxjava-1.3.8.jar:1.3.8]
	at com.netflix.hystrix.AbstractCommand$HystrixObservableTimeoutOperator$1.run(AbstractCommand.java:1142) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable$1.call(HystrixContextRunnable.java:41) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable$1.call(HystrixContextRunnable.java:37) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable.run(HystrixContextRunnable.java:57) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.AbstractCommand$HystrixObservableTimeoutOperator$2.tick(AbstractCommand.java:1159) ~[hystrix-core-1.5.18.jar:1.5.18]
	at com.netflix.hystrix.util.HystrixTimer$1.run(HystrixTimer.java:99) ~[hystrix-core-1.5.18.jar:1.5.18]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[na:1.8.0_25]
	at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) ~[na:1.8.0_25]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) ~[na:1.8.0_25]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) ~[na:1.8.0_25]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) ~[na:1.8.0_25]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) ~[na:1.8.0_25]
	at java.lang.Thread.run(Thread.java:745) [na:1.8.0_25]

原因：

hystrix:
    command:
      default:
        execution:
          timeout:
            enabled: true

开启了超时异常。可以关闭，关闭之后会转发到下一个实例。网上有说把hystrix的超时时间改长，也是可以的，总的时间可以是hystrix的超时时间=[（MaxAutoRetries+1）+ （MaxAutoRetriesNextServer+1）] * ReadTimeout

上边的例子改成[（2+1）+（1+1）] * 10000 = 50000.

hystrix:
    command:
      default:
        execution:
          timeout:
            enabled: true
          isolation:
            thread:
              timeoutInMilliseconds: 50000 #hystrix超时熔断时间

code：https://github.com/foxiaotao/spring-cloud-demo

收录于