frontend: add time management

frontend/main.go

@@ -1,18 +1,37 @@
 package main
 
 import (
+	"bufio"
 	"flag"
 	"fmt"
 	"log"
 	"net/http"
 	"os"
+	"path"
+	"time"
 )
 
+const startedFile = "started"
+
+var TeamsDir string
 var SubmissionDir string
 
+func touchStartedFile(startSub time.Duration) {
+	time.Sleep(startSub)
+	if fd, err := os.Create(path.Join(TeamsDir, startedFile)); err == nil {
+		log.Println("Started! Go, Go, Go!!")
+		fd.Close()
+	} else {
+		log.Println("Unable to start challenge:", err)
+	}
+}
+
 func main() {
 	var bind = flag.String("bind", "0.0.0.0:8080", "Bind port/socket")
 	var prefix = flag.String("prefix", "", "Request path prefix to strip (from proxy)")
+	var start = flag.Int64("start", 0, fmt.Sprintf("Challenge start timestamp (in 2 minutes: %d)", time.Now().Unix() / 60 * 60 + 120))
+	var duration = flag.Duration("duration", 180 * time.Minute, "Challenge duration")
+	flag.StringVar(&TeamsDir, "teams", "../TEAMS", "Base directory where save teams JSON files")
 	flag.StringVar(&SubmissionDir, "submission", "./submissions/", "Base directory where save submissions")
 	flag.Parse()
 
@@ -23,8 +42,30 @@ func main() {
 		}
 	}
 
+	startTime := time.Unix(*start, 0)
+	startSub := startTime.Sub(time.Now())
+	end := startTime.Add(*duration).Add(time.Duration(1 * time.Second))
+
+	log.Println("Challenge ends on", end)
+	if startSub > 0 {
+		log.Println("Challenge starts at", startTime, "in", startSub)
+
+		fmt.Printf("PRESS ENTER TO LAUNCH THE COUNTDOWN ")
+		bufio.NewReader(os.Stdin).ReadLine()
+
+		if _, err := os.Stat(path.Join(TeamsDir, startedFile)); !os.IsNotExist(err) {
+			os.Remove(path.Join(TeamsDir, startedFile))
+		}
+
+		go touchStartedFile(startTime.Sub(time.Now().Add(time.Duration(1 * time.Second))))
+	} else {
+		log.Println("Challenge started at", startTime, "since", -startSub)
+		go touchStartedFile(time.Duration(0))
+	}
+
 	log.Println("Registering handlers...")
-	http.Handle(fmt.Sprintf("%s/", *prefix), http.StripPrefix(*prefix, SubmissionHandler{}))
+	http.Handle(fmt.Sprintf("%s/time.json", *prefix), http.StripPrefix(*prefix, TimeHandler{startTime, *duration}))
+	http.Handle(fmt.Sprintf("%s/", *prefix), http.StripPrefix(*prefix, SubmissionHandler{end}))
 
 	log.Println(fmt.Sprintf("Ready, listening on %s", *bind))
 	if err := http.ListenAndServe(*bind, nil); err != nil {