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 () => {

deploy/front-end_nginx.conf

@@ -43,6 +43,25 @@ server {
     access_log /var/log/nginx/spanglish_frontend_access.log;
     error_log  /var/log/nginx/spanglish_frontend_error.log;
 
+    # LNbits payment SSE stream - must not be buffered or events won't flush in
+    # real time. Regex location takes precedence over the /api prefix below.
+    location ~ ^/api/lnbits/stream/ {
+        proxy_pass http://spanglish_backend;
+        proxy_http_version 1.1;
+
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_set_header Connection '';
+
+        # Disable buffering/caching for Server-Sent Events
+        proxy_buffering off;
+        proxy_cache off;
+        proxy_read_timeout 3600s;
+        proxy_connect_timeout 300s;
+    }
+
     # Proxy /api to backend
     location /api {
         proxy_pass http://spanglish_backend;

frontend/src/app/(public)/book/[eventId]/page.tsx

@@ -299,71 +299,75 @@ export default function BookingPage() {
     );
   };
 
-  // Connect to SSE for real-time payment updates
-  const connectPaymentStream = (ticketId: string) => {
-    const apiUrl = process.env.NEXT_PUBLIC_API_URL || '';
-    const eventSource = new EventSource(`${apiUrl}/api/lnbits/stream/${ticketId}`);
-    
+  // Watch for Lightning payment confirmation while on the paying step.
+  // SSE gives instant updates; a 3s poll runs in parallel as a safety net so a
+  // buffered/stuck stream (e.g. a proxy that doesn't flush SSE) can't strand the UI.
+  useEffect(() => {
+    if (step !== 'paying' || !bookingResult?.ticketId) return;
+
+    const ticketId = bookingResult.ticketId;
+    let settled = false;
+    let pollTimer: ReturnType<typeof setTimeout> | null = null;
+
+    const confirmPaid = () => {
+      if (settled) return;
+      settled = true;
+      toast.success(locale === 'es' ? '¡Pago confirmado!' : 'Payment confirmed!');
+      setPaymentPending(false);
+      setStep('success');
+    };
+
+    const expire = () => {
+      if (settled) return;
+      settled = true;
+      toast.error(locale === 'es' ? 'La factura ha expirado' : 'Invoice has expired');
+      setPaymentPending(false);
+    };
+
+    // Always same-origin so the streaming proxy route handler is used (it
+    // bypasses the rewrite, which buffers SSE).
+    const eventSource = new EventSource(`/api/lnbits/stream/${ticketId}`);
+
     eventSource.addEventListener('payment', (event) => {
       try {
-        const data = JSON.parse(event.data);
-        console.log('Payment event:', data);
-        
-        if (data.type === 'paid') {
-          toast.success(locale === 'es' ? '¡Pago confirmado!' : 'Payment confirmed!');
-          setPaymentPending(false);
-          setStep('success');
-          eventSource.close();
+        const data = JSON.parse((event as MessageEvent).data);
+        if (data.type === 'paid' || data.type === 'already_paid') {
+          confirmPaid();
         } else if (data.type === 'expired') {
-          toast.error(locale === 'es' ? 'La factura ha expirado' : 'Invoice has expired');
-          setPaymentPending(false);
-          eventSource.close();
-        } else if (data.type === 'already_paid') {
-          setPaymentPending(false);
-          setStep('success');
-          eventSource.close();
+          expire();
         }
       } catch (e) {
         console.error('Error parsing payment event:', e);
       }
     });
-    
-    eventSource.onerror = (error) => {
-      console.error('SSE error:', error);
-      // Fallback to polling if SSE fails
+
+    eventSource.onerror = () => {
+      // SSE failed or was closed; the poll below remains the source of truth.
       eventSource.close();
-      fallbackPoll(ticketId);
     };
-    
-    return eventSource;
-  };
-  
-  // Fallback polling if SSE is not available
-  const fallbackPoll = async (ticketId: string) => {
-    const maxAttempts = 60;
-    let attempts = 0;
-    
+
     const poll = async () => {
-      attempts++;
       try {
         const status = await ticketsApi.checkPaymentStatus(ticketId);
         if (status.isPaid) {
-          toast.success(locale === 'es' ? '¡Pago confirmado!' : 'Payment confirmed!');
-          setPaymentPending(false);
-          setStep('success');
+          confirmPaid();
           return;
         }
       } catch (error) {
         console.error('Error checking payment status:', error);
       }
-      
-      if (attempts < maxAttempts && paymentPending) {
-        setTimeout(poll, 5000);
+      if (!settled) {
+        pollTimer = setTimeout(poll, 3000);
       }
     };
-    
-    poll();
-  };
+    pollTimer = setTimeout(poll, 3000);
+
+    return () => {
+      settled = true;
+      eventSource.close();
+      if (pollTimer) clearTimeout(pollTimer);
+    };
+  }, [step, bookingResult?.ticketId, locale]);
 
   // Copy invoice to clipboard
   const copyInvoiceToClipboard = (invoice: string) => {
@@ -464,9 +468,7 @@ export default function BookingPage() {
         setBookingResult(result);
         setStep('paying');
         setPaymentPending(true);
-        
-        // Connect to SSE for real-time payment updates
-        connectPaymentStream(primaryTicket.id);
+        // Payment confirmation is handled by the paying-step watcher effect.
       } else if (formData.paymentMethod === 'bank_transfer' || formData.paymentMethod === 'tpago') {
         // Manual payment methods - show payment details
         setBookingResult({

frontend/src/app/api/lnbits/stream/[ticketId]/route.ts

@@ -0,0 +1,44 @@
+// Streaming proxy for the backend LNbits SSE endpoint.
+//
+// Next.js `rewrites` buffer `text/event-stream` responses, so payment events
+// never reach the browser in real time when going through the same-origin proxy.
+// This route handler streams the backend response body straight through with
+// anti-buffering headers, so EventSource on the booking page works in dev and
+// proxyless deployments. A route handler takes precedence over the rewrite.
+
+export const dynamic = 'force-dynamic';
+
+const BACKEND_URL = process.env.BACKEND_URL || 'http://localhost:3001';
+
+export async function GET(
+  request: Request,
+  { params }: { params: { ticketId: string } }
+) {
+  const upstream = await fetch(
+    `${BACKEND_URL}/api/lnbits/stream/${params.ticketId}`,
+    {
+      headers: { Accept: 'text/event-stream' },
+      signal: request.signal,
+    }
+  );
+
+  // If the ticket is already confirmed the backend may answer with JSON instead
+  // of a stream; pass that through unchanged so the client can handle it.
+  const contentType = upstream.headers.get('content-type') || '';
+  if (!contentType.includes('text/event-stream')) {
+    return new Response(upstream.body, {
+      status: upstream.status,
+      headers: { 'Content-Type': contentType || 'application/json' },
+    });
+  }
+
+  return new Response(upstream.body, {
+    status: upstream.status,
+    headers: {
+      'Content-Type': 'text/event-stream; charset=utf-8',
+      'Cache-Control': 'no-cache, no-transform',
+      Connection: 'keep-alive',
+      'X-Accel-Buffering': 'no',
+    },
+  });
+}