server/frontend/time.go

package main

import (
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"time"
)

var challengeStart time.Time

type TimeHandler struct {}

type timeObject struct {
	Started  int64 `json:"st"`
	Time     int64 `json:"cu"`
	Duration int   `json:"du"`
}

func (t TimeHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	log.Printf("Handling %s request from %s: %s [%s]\n", r.Method, r.RemoteAddr, r.URL.Path, r.UserAgent())

	w.Header().Set("Content-Type", "application/json")

	if j, err := json.Marshal(timeObject{challengeStart.Unix(), time.Now().Unix(), int(challengeEnd.Sub(challengeStart).Seconds())}); err != nil {
		http.Error(w, fmt.Sprintf("{\"errmsg\":\"%q\"}", err), http.StatusInternalServerError)
	} else {
		w.WriteHeader(http.StatusOK)
		w.Write(j)
	}
}