Go http.Get何时重用tcp连接？

Question

in GO net/http Response Body annotation says:

It is the caller's responsibility to close Body. The default HTTP client's Transport does not attempt to reuse HTTP/1.0 or HTTP/1.1 TCP connections ("keep-alive") unless the Body is read to completion and is closed.

It's mean: if I use http.Get and don't call resp.Body.Close() then it will not resue HTTP/1.0 or HTTP/1.1 TCP connections ("keep-alive") yeah?

so I write some code:

package main

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

func main() {
    resp, err := http.Get("http://127.0.0.1:8588")

if err != nil {
    panic(err)
}
_, err = ioutil.ReadAll(resp.Body)
if err != nil {
    panic(err)
}

resp2, err := http.Get("http://127.0.0.1:8588")

if err != nil {
    panic(err)
}
_, err = ioutil.ReadAll(resp2.Body)
if err != nil {
    panic(err)
}

fmt.Println("before time sleep")
time.Sleep(time.Second * 35)


}
     

and I only see ONE tcp connection build in wireshark, why? I don't close res.Body so the http client should't be reuse the tcp connection.

Answer 1

You have read it till the end in first occurence of line:

_, err = ioutil.ReadAll(resp.Body)

So the connection is ready to be resused. Try not to read and run again.