Webhook

Event occurs → Waffo Pancake → fan-out → Your channel(s)

{
  "id": "PAY_6eYCunG3IMmIgcQOnaXdoA",
  "timestamp": "2026-03-10T08:30:00.000Z",
  "eventType": "order.completed",
  "eventId": "PAY_6eYCunG3IMmIgcQOnaXdoA",
  "storeId": "STO_3bVzrkD0FJjFdZNLk8Ualx",
  "storeName": "My Store",
  "mode": "prod",
  "data": {
    "orderId": "ORD_5dXBtmF2HLlHfbPNm0Wcnz",
    "orderStatus": "completed",
    "buyerEmail": "buyer@example.com",
    "currency": "USD",
    "amount": "29.00",
    "taxAmount": "2.90",
    "taxRate": 0.1,
    "taxName": "Consumption Tax",
    "subtotal": "26.10",
    "total": "29.00",
    "productName": "Pro Plan",
    "orderMetadata": { "planId": "pro" },
    "productMetadata": {},
    "paymentId": "PAY_6eYCunG3IMmIgcQOnaXdoA",
    "paymentStatus": "succeeded",
    "paymentMethod": "card",
    "paymentLast4": "4242",
    "paymentDate": "2026-03-10"
  }
}

1. Parse t (timestamp in ms) and v1 (Base64 signature) from X-Waffo-Signature header
2. Build signature input: `${t}.${rawRequestBody}`
3. Verify v1 using RSA-SHA256 with the Waffo public key
4. (Recommended) Check that t is within 5 minutes of current time to prevent replay attacks

import { verifyWebhook, WebhookEventType } from "@waffo/pancake-ts";

app.post("/webhooks", express.raw({ type: "application/json" }), (req, res) => {
  try {
    const event = verifyWebhook(
      req.body.toString("utf-8"),
      req.headers["x-waffo-signature"] as string,
    );

    res.status(200).send("OK");

    switch (event.eventType) {
      case WebhookEventType.OrderCompleted:
        // Deliver digital goods
        break;
      case WebhookEventType.SubscriptionActivated:
        // Provision subscription access
        break;
      case WebhookEventType.SubscriptionCanceled:
        // Revoke access
        break;
    }
  } catch {
    res.status(401).send("Invalid signature");
  }
});

// Recommended: respond immediately, process async
app.post('/webhooks', (req, res) => {
  res.status(200).send('OK');
  processEventAsync(req.body);
});

async function handleEvent(event) {
  const exists = await db.query(
    'SELECT 1 FROM processed_webhooks WHERE event_type = $1 AND event_id = $2',
    [event.eventType, event.eventId]
  );
  if (exists.rows.length > 0) return; // Already processed

  await processEventLogic(event);

  await db.query(
    'INSERT INTO processed_webhooks (event_type, event_id, processed_at) VALUES ($1, $2, NOW())',
    [event.eventType, event.eventId]
  );
}

ngrok http 8080
# Use the generated URL as your Test Webhook URL
# e.g., https://abc123.ngrok.io/webhooks