use the server startup time to drop old cached tickets

2 files changed, 22 insertions, 8 deletions

diff --git a/index.html b/index.html
index bb1b6ca..bcda425 100644
--- a/index.html
+++ b/index.html
@@ -80,7 +80,7 @@ button {
       function requestHelp() {
         new HttpClient().get("new", (myNumber) => {
           myTicket = myNumber;
-          localStorage.setItem("my-ticket", myTicket);
+          localStorage.setItem("my-ticket", JSON.stringify({"t": myTicket, "e": Date.now()}));
           showTicket();
         });
       }
@@ -119,9 +119,17 @@ button {
 
       var myTicket;
       function init() {
-	      myTicket = localStorage.getItem("my-ticket");
-	      if (myTicket)
-	        showTicket();
+	      const cached = JSON.parse(localStorage.getItem("my-ticket"));
+	      if (!cached) return;
+
+	      const serverEpoch = Date.parse(document.getElementById("epoch").textContent);
+	      if (cached.e < serverEpoch) {
+            localStorage.removeItem("my-ticket");
+            return;
+          }
+
+	      myTicket = cached.t;
+	      showTicket();
       }
 
       if (document.readyState === "loading") {
@@ -133,6 +141,7 @@ button {
     </script>
   </head>
   <body>
+    <div id="epoch" style="display: none;">{{.StartTime}}</div>
     <div id="next">
       Nächstes Hilfe Ticket
       <span id="done">{{.Done}}</span>
diff --git a/main.go b/main.go
index adcb194..aa5b52b 100644
--- a/main.go
+++ b/main.go
@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"strconv"
 	"sync/atomic"
+	"time"
 )
 
 //go:embed index.html
@@ -18,6 +19,7 @@ var pageTemplate *template.Template
 
 var open atomic.Uint64
 var done atomic.Uint64
+var start time.Time
 
 var broker *Broker
 
@@ -144,10 +146,11 @@ func pageHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	tempData := struct {
-		Open    uint64
-		Done    uint64
-		IsAdmin bool
-	}{open.Load(), done.Load() + 1, r.URL.Query().Has(*passwd)}
+		Open      uint64
+		Done      uint64
+		StartTime string
+		IsAdmin   bool
+	}{open.Load(), done.Load() + 1, start.Format(time.RFC3339), r.URL.Query().Has(*passwd)}
 
 	if err := pageTemplate.Execute(w, tempData); err != nil {
 		http.Error(w, err.Error(), http.StatusInternalServerError)
@@ -178,6 +181,8 @@ var passwd = flag.String("password", "admin", "the admin password")
 func main() {
 	flag.Parse()
 
+	start = time.Now()
+
 	broker = &Broker{
 		make(map[chan string]bool),
 		make(chan (chan string)),