panic: WriteHeader called after Handler finished

[kwzcoder]

加了熔断部署在云服务器上会偶发panic: WriteHeader called after Handler finished

micro Api panic 必现步骤 : 1. 先把熔断阀值调高 hystrix.DefaultMaxConcurrent = 100000 hystrix.DefaultVolumeThreshold = 100000 2. 熔断超时调低 hystrix.DefaultTimeout = 100 3 .用压测工具 webbench 高并发请求接口必panic "panic: net/http: CloseNotify called after ServeHTTP finished"

熔断代码如下: `package hystrix

import ( "errors" "fmt" "log" "net/http" status_code "qtimes.cc/galileo/microservices/lib/http" "github.com/afex/hystrix-go/hystrix" )

func init() { log.Println(" hystrix init ----------") hystrix.DefaultTimeout = 10000 //hystrix.DefaultMaxConcurrent = 100000 //hystrix.DefaultVolumeThreshold = 100000 } // BreakerWrapper hystrix breaker func BreakerWrapper(h http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { name := r.Method + "-" + r.RequestURI log.Println(name)

	err := hystrix.Do(name, func() error {
		//log.Println("hystrix.DefaultTimeout =  ",hystrix.DefaultTimeout)
		//log.Println("hystrix.DefaultMaxConcurrent =  ",hystrix.DefaultMaxConcurrent)
		sct := &status_code.StatusCodeTracker{ResponseWriter: w, Status: http.StatusOK}
		h.ServeHTTP(sct.WrappedResponseWriter(), r)

		if sct.Status >= http.StatusBadRequest {
			str := fmt.Sprintf("status code %d", sct.Status)
			log.Println(str)
			return errors.New(str)
		}
		return nil
	}, nil)

	if err != nil {
		log.Println("hystrix breaker err: ", err)
		return
	}
})

} `

[printfcoder]

#52