问将http响应流式传输到http ResponseWriter

EN

package main

import (
    "fmt"
    "io"
    "net/http"
    "time"

    "github.com/gorilla/mux"
)

func main() {
    router := mux.NewRouter()
    router.Path("/test").HandlerFunc(Stream).Methods("GET")

    srv := &http.Server{
        Addr:         ":4000",
        Handler:      router,
        ReadTimeout:  30 * time.Minute,
        WriteTimeout: 30 * time.Minute,
        IdleTimeout:  60 * time.Minute,
    }

    srv.SetKeepAlivesEnabled(true)

    fmt.Println(srv.ListenAndServe())
}

// Stream .
func Stream(w http.ResponseWriter, r *http.Request) {
    req, err := http.NewRequest("GET", "https://lh3.googleusercontent.com/k3ysodYwXwhm7ThrM_-zbqhETk8CUfMd5vuG9RbjBKrKAKQaUfZpiRRDg8ZEaT-WfsDkRfS_cheTM4JvT3TEoNEPF4gzofkq0Y6ykGVT_WhG4hXG-nAdkpeyeY1kMysqBWdS5YDGIPY=d", nil)
    if err != nil {
        return
    }

    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        return
    }
    defer resp.Body.Close()

    w.Header().Set("content-type", "video/mp4")
    w.WriteHeader(206)
    w.Header().Set("Status", "206")

    i, err := io.Copy(w, resp.Body)
    fmt.Println(i, err)
}