PHP
·
发表于 5年以前
·
阅读量:8398
package main
import (
"fmt"
"net"
"net/http"
"os"
"os/signal"
"sync/atomic"
"syscall"
"time"
)
func slow(res http.ResponseWriter, req *http.Request) {
fmt.Println("respond at=start")
time.Sleep(time.Second * 5)
res.Header().Set("Content-Type", "text/plain")
fmt.Fprintln(res, "Finally.")
fmt.Println("respond at=finish")
}
var connCount int64 = 0
type watchedConn struct {
net.Conn
}
func (w *watchedConn) Close() error {
atomic.AddInt64(&connCount, -1)
return w.Conn.Close()
}
type watchedListener struct {
net.Listener
}
func (l *watchedListener) Accept() (net.Conn, error) {
conn, err := l.Listener.Accept()
if err != nil {
return nil, err
}
atomic.AddInt64(&connCount, 1)
return &watchedConn{Conn: conn}, nil
}
func main() {
stop := make(chan bool, 1)
sig := make(chan os.Signal, 1)
handler := http.HandlerFunc(slow)
server := &http.Server{Handler: handler}
fmt.Println("listen at=start")
listener, listenErr := net.Listen("tcp", ":5000")
if listenErr != nil {
panic(listenErr)
}
wListener := &watchedListener{Listener: listener}
fmt.Println("listen at=finish")
go func() {
<-stop
fmt.Println("close at=start")
closeErr := wListener.Close()
if closeErr != nil {
panic(closeErr)
}
fmt.Println("close at=finish")
}()
go func() {
signal.Notify(
sig, syscall.SIGINT,
syscall.SIGTERM)
fmt.Println("trap at=start")
<-sig
stop <- true
fmt.Println("trap at=finish")
}()
fmt.Println("serve at=start")
server.Serve(wListener)
fmt.Println("serve at=finish")
for {
connCountCurrent := atomic.LoadInt64(&connCount)
if connCountCurrent > 0 {
fmt.Println("wait at=pending remaining=",
connCountCurrent)
time.Sleep(time.Second)
} else {
fmt.Println("wait at=finish remaining=",
connCountCurrent)
return
}
}
}