fix data race

main.go

@@ -24,7 +24,7 @@ import (
 var upgrader = websocket.Upgrader{
 	CheckOrigin: func(r *http.Request) bool {
 		origin := r.Header.Get("Origin")
-		return origin == "https://ddlion.net" || origin == "https://ddln.app"
+		return origin == "https://ddlion.net" || origin == "https://ddln.app" || origin == "https://localhost:6789"
 	},
 }
 
@@ -68,6 +68,7 @@ type Peer struct {
 	conn       *websocket.Conn
 	send       chan []byte
 	lastActive time.Time
+	m          sync.Mutex
 	closeOnce  sync.Once
 }
 
@@ -118,7 +119,9 @@ func handleWebSocket(w http.ResponseWriter, r *http.Request) {
 			break
 		}
 
+		peer.m.Lock()
 		peer.lastActive = time.Now()
+		peer.m.Unlock()
 
 		// fmt.Println("ws<-", connectionPeers[conn], ":", string(message[:min(80, len(message))]))
 
@@ -413,9 +416,11 @@ func main() {
 				// Collect inactive peers
 				var inactivePeers []string
 				for peerID, peer := range peerConnections {
+					peer.m.Lock()
 					if now.Sub(peer.lastActive) > 60*time.Second {
 						inactivePeers = append(inactivePeers, peerID)
 					}
+					peer.m.Unlock()
 				}
 
 				// Remove inactive peers