TUN-528: Move cloudflared into a separate repo

vendor/github.com/facebookgo/grace/gracedemo/demo.go

@@ -0,0 +1,50 @@
+// Command gracedemo implements a demo server showing how to gracefully
+// terminate an HTTP server using grace.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/facebookgo/grace/gracehttp"
+)
+
+var (
+	address0 = flag.String("a0", ":48567", "Zero address to bind to.")
+	address1 = flag.String("a1", ":48568", "First address to bind to.")
+	address2 = flag.String("a2", ":48569", "Second address to bind to.")
+	now      = time.Now()
+)
+
+func main() {
+	flag.Parse()
+	gracehttp.Serve(
+		&http.Server{Addr: *address0, Handler: newHandler("Zero  ")},
+		&http.Server{Addr: *address1, Handler: newHandler("First ")},
+		&http.Server{Addr: *address2, Handler: newHandler("Second")},
+	)
+}
+
+func newHandler(name string) http.Handler {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/sleep/", func(w http.ResponseWriter, r *http.Request) {
+		duration, err := time.ParseDuration(r.FormValue("duration"))
+		if err != nil {
+			http.Error(w, err.Error(), 400)
+			return
+		}
+		time.Sleep(duration)
+		fmt.Fprintf(
+			w,
+			"%s started at %s slept for %d nanoseconds from pid %d.\n",
+			name,
+			now,
+			duration.Nanoseconds(),
+			os.Getpid(),
+		)
+	})
+	return mux
+}