Golang1.8.1: TimeoutHandler doesn't affect multiplexer

I have this code which redirect http/s requests to login page, it works except TimeoutHandler has no effect, I mean the sessions don't timeout after 3 seconds:

func main(){

        mux := http.NewServeMux()
        rh := http.RedirectHandler("http://10.130.0.10:820/login", 307)
        mux.Handle("/", rh)
        tmux := http.TimeoutHandler(mux, time.Second*3, "Timeout!")
        go http.ListenAndServe("10.130.0.10:818", tmux)
        go http.ListenAndServeTLS("10.130.0.10:821", "server.pem", "server.key", tmux)
        var input string
        fmt.Scanln(&input)
        fmt.Println("done")
}

any advice will be appreciated.

The http.TimeoutHandler is not for making session expired after a certain time. Instead, it's used to limit execution time of a handler, i.e. if given time is elapsed, it will return 503 Service Unavailable to HTTP client. Below is an example of such usage:

func handlerNoTimeout(w http.ResponseWriter, r *http.Request) {
    //This handler takes 1 second to finished, won't timeout
    time.Sleep(1 * time.Second)
    w.Write([]byte("Handler OK"))
}

func handlerTimeout(w http.ResponseWriter, r *http.Request) {
    //This handler takes 4 seconds to finished.
    //Before finished, it will timeout, 
    //503 response will be sent to client + given message (i.e. Timeout!)
    time.Sleep(4 * time.Second)
    w.Write([]byte("Handler timeout (never executed)"))
}

func main() {

    mux := http.NewServeMux()
    rh := http.RedirectHandler("http://10.130.0.10:820/login", 307)
    mux.Handle("/", rh)
    mux.HandleFunc("/timeout", handlerTimeout)
    mux.HandleFunc("/notimeout", handlerNoTimeout)
    tmux := http.TimeoutHandler(mux, time.Second*3, "Timeout!")
    go http.ListenAndServe(":818", tmux)
    go http.ListenAndServeTLS(":821", "server.pem", "server.key", tmux)
    var input string
    fmt.Scanln(&input)
    fmt.Println("done")
}

If your access /timeout, you will get 503 with timeout message, but if you access /notimeout, the http response will be 200 OK.

A session is a state stored by the server, not a processing steps/task/job which may needs time to finish. A session won't expired unless you define a function/method/handler in background, watch the session creation time regularly, and if given time elapsed, mark it as expired.

In your code, it will timeout if redirect handler (i.e. login handler) needs more than 3 seconds.

I figured it out, I had to use ReadTimeout and WriteTimeout instead, here is a working example.

func main(){
        mux := http.NewServeMux()
        rh := http.RedirectHandler("http://10.103.0.10:8020/login", 307)
        mux.Handle("/", rh)
        s := &http.Server{
	        Addr:		"10.103.0.10:818",
	        Handler:        mux,
	        ReadTimeout:    5 * time.Second,
	        WriteTimeout:   5 * time.Second,
        }
        ss := &http.Server{
	        Addr:		"10.103.0.10:821",
	        Handler:        mux,
	        ReadTimeout:    5 * time.Second,
	        WriteTimeout:   5 * time.Second,
        }
        go s.ListenAndServe()
        go ss.ListenAndServeTLS("server.pem", "server.key")

        var input string
        fmt.Scanln(&input)
        fmt.Println("done")
    }

Thank you.