Fix Lightning payment UI not updating after LNbits invoice is paid.

Ensure the booking page receives payment confirmation via a streaming SSE proxy, parallel status polling, and more reliable backend event delivery.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/src/routes/lnbits.ts

@@ -9,7 +9,7 @@ import emailService from '../lib/email.js';
 const lnbitsRouter = new Hono();
 
 // Store for active SSE connections (ticketId -> Set of response writers)
-const activeConnections = new Map<string, Set<(data: any) => void>>();
+const activeConnections = new Map<string, Set<(data: any) => Promise<void>>>();
 
 // Store for active background checkers (ticketId -> intervalId)
 const activeCheckers = new Map<string, NodeJS.Timeout>();
@@ -34,16 +34,18 @@ interface LNbitsWebhookPayload {
 /**
  * Notify all connected clients for a ticket
  */
-function notifyClients(ticketId: string, data: any) {
+async function notifyClients(ticketId: string, data: any) {
   const connections = activeConnections.get(ticketId);
   if (connections) {
-    connections.forEach(send => {
-      try {
-        send(data);
-      } catch (e) {
-        // Connection might be closed
-      }
-    });
+    await Promise.all(
+      Array.from(connections).map(async (send) => {
+        try {
+          await send(data);
+        } catch (e) {
+          // Connection might be closed
+        }
+      })
+    );
   }
 }
 
@@ -71,7 +73,7 @@ function startBackgroundChecker(ticketId: string, paymentHash: string, expirySec
       console.log(`Invoice expired for ticket ${ticketId}`);
       clearInterval(checkInterval);
       activeCheckers.delete(ticketId);
-      notifyClients(ticketId, { type: 'expired', ticketId });
+      await notifyClients(ticketId, { type: 'expired', ticketId });
       return;
     }
 
@@ -84,7 +86,7 @@ function startBackgroundChecker(ticketId: string, paymentHash: string, expirySec
         activeCheckers.delete(ticketId);
         
         await handlePaymentComplete(ticketId, paymentHash);
-        notifyClients(ticketId, { type: 'paid', ticketId, paymentHash });
+        await notifyClients(ticketId, { type: 'paid', ticketId, paymentHash });
       }
     } catch (error) {
       console.error(`Error checking payment for ticket ${ticketId}:`, error);
@@ -165,7 +167,7 @@ lnbitsRouter.post('/webhook', async (c) => {
     await handlePaymentComplete(ticketId, payload.payment_hash);
     
     // Notify connected clients via SSE
-    notifyClients(ticketId, { type: 'paid', ticketId, paymentHash: payload.payment_hash });
+    await notifyClients(ticketId, { type: 'paid', ticketId, paymentHash: payload.payment_hash });
     
     return c.json({ received: true, processed: true }, 200);
   } catch (error) {
@@ -264,38 +266,39 @@ lnbitsRouter.get('/stream/:ticketId', async (c) => {
     return c.json({ error: 'Ticket not found' }, 404);
   }
   
-  // If already paid, return immediately
-  if (ticket.status === 'confirmed') {
-    return c.json({ type: 'already_paid', ticketId }, 200);
-  }
-  
   // Get payment to start background checker
   const payment = await dbGet<any>(
     (db as any).select().from(payments).where(eq((payments as any).ticketId, ticketId))
   );
   
-  // Start background checker if not already running
-  if (payment?.reference && !activeCheckers.has(ticketId)) {
+  // Start background checker if not already running (only while still pending)
+  if (ticket.status !== 'confirmed' && payment?.reference && !activeCheckers.has(ticketId)) {
     startBackgroundChecker(ticketId, payment.reference, 900); // 15 min expiry
   }
   
+  // Prevent proxies/CDNs from buffering the event stream so events flush immediately.
+  c.header('Cache-Control', 'no-cache, no-transform');
+  c.header('X-Accel-Buffering', 'no');
+  
   return streamSSE(c, async (stream) => {
+    const sendEvent = async (data: any) => {
+      await stream.writeSSE({ data: JSON.stringify(data), event: 'payment' });
+    };
+    
+    // If already paid, notify over SSE and close (EventSource can parse this).
+    if (ticket.status === 'confirmed') {
+      await sendEvent({ type: 'already_paid', ticketId });
+      return;
+    }
+    
     // Register this connection
     if (!activeConnections.has(ticketId)) {
       activeConnections.set(ticketId, new Set());
     }
-    
-    const sendEvent = (data: any) => {
-      stream.writeSSE({ data: JSON.stringify(data), event: 'payment' });
-    };
-    
     activeConnections.get(ticketId)!.add(sendEvent);
     
     // Send initial status
-    await stream.writeSSE({ 
-      data: JSON.stringify({ type: 'connected', ticketId }), 
-      event: 'payment' 
-    });
+    await sendEvent({ type: 'connected', ticketId });
     
     // Keep connection alive with heartbeat
     const heartbeat = setInterval(async () => {