Webhooks de transacao

{
  "event": "transaction.completed",
  "timestamp": "2026-04-01T22:15:40.000Z",
  "data": {
    "id": 115,
    "referenceId": "e1de94c1-5692-48e1-a334-24b367ad76ff",
    "status": "COMPLETED",
    "type": "CASHIN",
    "checkoutSessionId": "checkout_sess_abc123",
    "paymentIntentId": "payment_abc123",
    "trackingParameters": {
      "utm_source": "meta_ads",
      "utm_medium": "cpc",
      "utm_campaign": "black_friday",
      "utm_content": "criativo_1",
      "utm_term": "checkout"
    },
    "tracking_parameters": {
      "utm_source": "meta_ads",
      "utm_medium": "cpc",
      "utm_campaign": "black_friday",
      "utm_content": "criativo_1",
      "utm_term": "checkout"
    },
    "utm_source": "meta_ads",
    "utm_medium": "cpc",
    "utm_campaign": "black_friday"
  }
}

import crypto from "crypto";

function validateWebhookSignature(rawBody, signature, secret) {
  const expected = crypto.createHmac("sha256", secret).update(rawBody).digest("hex");
  const sigBuf = Buffer.from(signature || "", "utf8");
  const expBuf = Buffer.from(expected, "utf8");
  if (sigBuf.length !== expBuf.length) return false;
  return crypto.timingSafeEqual(sigBuf, expBuf);
}