Improve Socket.IO logging and connection handling

- Enhanced logging during WebSocket upgrade attempts by including specific headers for better debugging.
- Updated frontend socket service to allow forced upgrade attempts after successful polling connections, improving connection reliability.

backend/services/socketService.js

@@ -50,14 +50,17 @@ export const initializeSocketIO = (httpServer) => {
   // Verbesserte WebSocket-Upgrade-Logging
   io.engine.on('upgrade', (req, socket, head) => {
     console.log(`🔄 Socket.IO Upgrade-Versuch: ${req.url}`);
-    console.log(`   Headers:`, req.headers);
+    console.log(`   Upgrade-Header: ${req.headers.upgrade}`);
+    console.log(`   Connection-Header: ${req.headers.connection}`);
+    console.log(`   Sec-WebSocket-Key: ${req.headers['sec-websocket-key']?.substring(0, 20)}...`);
   });
   
   io.engine.on('upgradeError', (err, req, socket, head) => {
     console.error('❌ Socket.IO Upgrade Error:', err.message || err);
     if (req) {
       console.error('   URL:', req.url);
-      console.error('   Headers:', req.headers);
+      console.error('   Upgrade-Header:', req.headers.upgrade);
+      console.error('   Connection-Header:', req.headers.connection);
       console.error('   Method:', req.method);
     }
     if (err.stack) {

frontend/src/services/socketService.js

@@ -85,14 +85,16 @@ export const connectSocket = (clubId) => {
       reconnectionDelayMax: 5000,
       reconnectionAttempts: Infinity, // Unbegrenzte Versuche
       timeout: 20000,
-      upgrade: true,
+      upgrade: true, // Erlaube Upgrade von Polling zu WebSocket
       forceNew: false,
       secure: isHttps, // Nur für HTTPS
       rejectUnauthorized: false, // Für selbst-signierte Zertifikate (nur Entwicklung)
       // Verbesserte Cookie-Handling
       withCredentials: true,
       // Auto-Connect
-      autoConnect: true
+      autoConnect: true,
+      // Erzwinge Upgrade-Versuch nach erfolgreicher Polling-Verbindung
+      rememberUpgrade: true
     });
 
     socket.on('connect', () => {