Webhooks

const express = require('express');
const { PayX } = require('payx-node');

const app = express();
app.use(express.json());

const payx = new PayX({ apiKey: process.env.PAYX_SECRET_KEY });

app.post('/webhooks', (req, res) => {
  const signature = req.headers['x-payx-signature'];
  const webhookSecret = process.env.PAYX_WEBHOOK_SECRET; // starts with whsec_live_... or whsec_test_...
  
  const isValid = payx.webhooks.verifySignature(
    req.body, 
    signature, 
    webhookSecret
  );

  if (!isValid) {
    return res.status(401).send('Invalid Signature');
  }

  const { event, data } = req.body;
  console.log(`Received event: ${event}`, data);

  // Acknowledge receipt promptly
  res.status(200).send('OK');
});

app.listen(3000, () => console.log('Webhook server running on port 3000'));

const crypto = require('crypto');

function verifyPayXSignature(rawBody, signatureHeader, secret) {
  const computedSignature = crypto
    .createHmac('sha256', secret)
    .update(typeof rawBody === 'string' ? rawBody : JSON.stringify(rawBody))
    .digest('hex');

  return crypto.timingSafeEqual(
    Buffer.from(computedSignature, 'utf8'),
    Buffer.from(signatureHeader, 'utf8')
  );
}

{
  "event": "transaction.success",
  "data": {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "reference": "ORD-2026-9810",
    "amount": 100.00,
    "currency": "GHS",
    "status": "SUCCESSFUL",
    "type": "CHARGE",
    "customer": {
      "phoneNumber": "0551234987",
      "network": "MTN",
      "email": "customer@example.com"
    },
    "createdAt": "2026-09-09T22:15:30.000Z",
    "metadata": {
      "orderId": "ORD-2026-9810"
    }
  }
}

{
  "event": "transaction.failed",
  "data": {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "reference": "ORD-2026-9810",
    "amount": 100.00,
    "currency": "GHS",
    "status": "FAILED",
    "type": "CHARGE",
    "failureReason": "INSUFFICIENT_FUNDS",
    "customer": {
      "phoneNumber": "0551234987",
      "network": "MTN",
      "email": "customer@example.com"
    },
    "createdAt": "2026-09-09T22:15:30.000Z"
  }
}