tam 2

management/src/components/ExamGridProctor.tsx

@@ -56,6 +56,15 @@ export const ExamGridProctor: React.FC<ExamGridProctorProps> = ({
     const wsUrl = getWsUrl('/ws?role=teacher');
     let closed = false;
     let retryTimer: ReturnType<typeof setTimeout> | null = null;
+    let pingTimer: ReturnType<typeof setInterval> | null = null;
+    let attempt = 0;
+
+    const clearPing = () => {
+      if (pingTimer) {
+        clearInterval(pingTimer);
+        pingTimer = null;
+      }
+    };
 
     const connect = () => {
       if (closed) return;
@@ -64,11 +73,21 @@ export const ExamGridProctor: React.FC<ExamGridProctorProps> = ({
       wsRef.current = ws;
       subscribedRef.current = new Set();
 
-      ws.onopen = () => syncSubscriptions(ws);
+      ws.onopen = () => {
+        attempt = 0;
+        syncSubscriptions(ws);
+        clearPing();
+        pingTimer = setInterval(() => {
+          if (ws.readyState === WebSocket.OPEN) {
+            ws.send(JSON.stringify({ event: 'client:ping', data: {} }));
+          }
+        }, 15000);
+      };
 
       ws.onmessage = (event) => {
         try {
           const msg = JSON.parse(event.data);
+          if (msg.event === 'client:pong') return;
           if (msg.event === 'teacher:screenshot-stream-frame') {
             const { studentId, imageBuffer } = msg.data;
             setScreenFrames((prev) => ({ ...prev, [studentId]: imageBuffer }));
@@ -94,9 +113,11 @@ export const ExamGridProctor: React.FC<ExamGridProctorProps> = ({
       };
 
       ws.onclose = () => {
+        clearPing();
         subscribedRef.current = new Set();
         if (!closed) {
-          retryTimer = setTimeout(connect, 3000);
+          const delay = Math.min(1000 * 2 ** Math.min(attempt++, 4), 10000);
+          retryTimer = setTimeout(connect, delay);
         }
       };
     };
@@ -105,6 +126,7 @@ export const ExamGridProctor: React.FC<ExamGridProctorProps> = ({
 
     return () => {
       closed = true;
+      clearPing();
       if (retryTimer) clearTimeout(retryTimer);
       const ws = wsRef.current;
       if (ws?.readyState === WebSocket.OPEN) {