feign.hystrix.enabled开启后client timeout参数设置

openfeign: feign.hystrix.enabled = true

feign.hystrix.enabled = true 标识开启hystrix

1、springcloud版本

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-dependencies</artifactId>
    <version>Hoxton.SR11</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-dependencies</artifactId>
    <version>2.3.5.RELEASE</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>

2、yml配置

feign:
  hystrix:
    enabled: true	
hystrix:
  command:
    default:
      execution:
        isolation:
          thread:
            timeoutInMilliseconds: 3000
        thread:
          timeoutInMilliseconds: 1000    

3、代码分析

• @EnableFeignClients

  • 会加载FeignClientsRegistrar到spring容器且执行registerBeanDefinitions方法;
  • 调用registerFeignClients扫描解析所有@FeignClient的类解析成BeanDefinition到容器，且参数feignClientsRegistrarFactoryBean是FeignClientFactoryBean对象；

• 实例化FeignClient

  • FeignClientFactoryBean.getObject()
    • getTarget()
      • loadBalance()
        • … 最终return FeignInvocationHandler;

• FeignClient调用

  • HystrixInvocationHandler.invoke()
    • new HystrixCommand(setterMethodMap.get(method)) {…}.execute()

• hystrix.command.default相关参数生效顺序 D A B C 啥都没配置 默认值
  源码如下

  	public HystrixDynamicProperty<T> build() {
          if (properties.size() < 1) throw new IllegalArgumentException();
          if (properties.size() == 1) return properties.get(0);
          List<HystrixDynamicProperty<T>> reversed = 
                  new ArrayList<HystrixDynamicProperty<T>>(properties);
          Collections.reverse(reversed);
          ChainProperty<T> current = null;
          for (HystrixDynamicProperty<T> p : reversed) {
              if (current == null) {
                  current = new ChainProperty<T>(p);
              }
              else {
                  current = new ChainProperty<T>(p, current);
              }
          }
          return new ChainHystrixProperty<T>(current);
      }
  

  • A、@FeignClient(configuration = FeignConfig.class) ，重写Feign.Builder.SetterFactory，相关设置参数会写到setterMethodMap供上述代码调用;

    @FeignClient(value = "service-X", configuration = configX.class, fallbackFactory = ServiceCallFailBack.class)
    

  • B、定义全局的Feign.Builder

    @Configuration(proxyBeanMethods = false)
     @ConditionalOnClass({ HystrixCommand.class, HystrixFeign.class })
    public class FeignConfig {
        @Bean
        @Scope("prototype")
        @ConditionalOnProperty(name = "feign.hystrix.enabled")
        public Feign.Builder feignHystrixBuilder() {
            HystrixFeign.Builder builder = HystrixFeign.builder();
            SetterFactory setterFactory= new SetterFactory(){
                @Override
                public HystrixCommand.Setter create(Target<?> target, Method method) {
                    String groupKey = target.name();
                    String commandKey = Feign.configKey(target.type(), method);
                    HystrixThreadPoolProperties.Setter setter = HystrixThreadPoolProperties.Setter().withCoreSize(100).withMaxQueueSize(300);
                    HystrixCommandProperties.Setter setter1 = HystrixCommandProperties.Setter().withExecutionTimeoutInMilliseconds(8000);
                    return HystrixCommand.Setter
                            .withGroupKey(HystrixCommandGroupKey.Factory.asKey(groupKey))
                            .andCommandKey(HystrixCommandKey.Factory.asKey(commandKey))
                            .andThreadPoolPropertiesDefaults(setter)
                            .andCommandPropertiesDefaults(setter1);
    
    
                }
            };
            builder.setterFactory(setterFactory);
            return builder;
        }
    }
    

  • C、配置文件读取第一种

     hystrix:
    	 command:
    	    default:
    	      execution:
    	        isolation:
    	          thread:
    	            timeoutInMilliseconds: 3000
    	        thread:
    	          timeoutInMilliseconds: 1000
    

  • D、配置文件读取第二中

     hystrix:
    	  command:
    	    ServiceClient#getMethod(Integer):
    	      execution:
    	        isolation:
    	          thread:
    	            timeoutInMilliseconds: 5000
    	        thread:
    	          timeoutInMilliseconds: 5000