net/http: Client can't close HTTP stream.

[dustin]

I can't seem to close an HTTP response body while it's still sending data.  I ran into
this in an app I was writing, but I believe the following client and server demonstrate
the problem (sorry, not sure how to write a trustworthy test for this):


// server.go:

package main

import (
    "log"
    "net/http"
    "time"
)

func foreverYoung(w http.ResponseWriter, req *http.Request) {
    w.Header().Set("Content-type", "application/javascript")
    w.Header().Set("Access-Control-Allow-Origin", "*")
    w.WriteHeader(200)

    for {
        w.Write([]byte("young\r\n"))
        w.(http.Flusher).Flush()
        time.Sleep(time.Second)
    }
}

func main() {
    http.HandleFunc("/", foreverYoung)
    log.Fatal(http.ListenAndServe(":4334", nil))
}




// client.go:

package main

import (
    "log"
    "net/http"
    "os"
)

func main() {
    resp, err := http.Get("http://localhost:4334/";)
    if err == nil {
        func() {
            defer resp.Body.Close()
            for {
                b := []byte{0}
                _, err := resp.Body.Read(b)
                if err != nil {
                    log.Fatalf("Error reading stuff: %v", err)
                }
                os.Stdout.Write(b)
                if b[0] == byte('\n') {
                    return
                }
            }
        }()
    } else {
        log.Fatalf("Error in stream: %v", err)
    }
}

[bradfitz]

Comment 1:

Labels changed: removed priority-triage.

Owner changed to @bradfitz.

Status changed to Accepted.

[rsc]

Comment 2:

Labels changed: added go1.1.

[shanemhansen]

Comment 3:

So, it seems like the right thing to do here is eliminate the call to
io.Copy(ioutil.Discard, b) in transfer.go, right?
Seems like the only reasonable alternative is to set a timeout and return from Close if
the discard operation doesn't complete in some reasonable amount of time.
I understand that failing to consume a response body would be really bad, esp wrt to
connection pooling, so it's tough to tell what the right thing to do here is.

[rsc]

Comment 4:

Labels changed: added size-l.

[bradfitz]

Comment 5:

I've mailed out https://golang.org/cl/7419050
Please test it.

Status changed to Started.

[bradfitz]

Comment 6:

This issue was closed by revision ce83415.

Status changed to Fixed.