Webhooks — Real-Time Payment Notifications

import { PayNodeWebhookNotifier } from '@paynodelabs/sdk-js';
 
const notifier = new PayNodeWebhookNotifier({
  rpcUrl: 'https://mainnet.base.org',
  contractAddress: '0x4A73696ccF76E7381b044cB95127B3784369Ed63',
  webhookUrl: 'https://your-server.com/api/paynode-webhook',
  webhookSecret: process.env.WEBHOOK_SECRET,  // For HMAC signature
  chainId: 8453,
  pollIntervalMs: 5000,                        // Default: 5 seconds
  onSuccess: (event) => console.log(`Payment received: ${event.txHash}`),
  onError: (err, event) => console.error(`Delivery failed: ${err.message}`),
});
 
// Start listening
await notifier.start();
 
// Stop when shutting down
notifier.stop();

from paynode_sdk import PayNodeWebhookNotifier
 
notifier = PayNodeWebhookNotifier(
    rpc_url="https://mainnet.base.org",
    contract_address="0x4A73696ccF76E7381b044cB95127B3784369Ed63",
    webhook_url="https://your-server.com/api/paynode-webhook",
    webhook_secret=os.getenv("WEBHOOK_SECRET"),
    chain_id=8453,
    poll_interval_seconds=5.0,
    on_success=lambda e: print(f"Payment: {e.tx_hash}"),
    on_error=lambda e, ev: print(f"Failed: {e}"),
)
 
# Start listening (async)
await notifier.start()
 
# Stop
await notifier.stop()

{
  "event": "payment.received",
  "data": {
    "txHash": "0xabc123...",
    "blockNumber": 12345678,
    "orderId": "0x7f83b1657ff1fc53b92dc...",
    "merchant": "0xMerchantAddress...",
    "payer": "0xPayerAddress...",
    "token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000000",
    "fee": "10000",
    "chainId": "8453",
    "timestamp": 1716000000
  }
}

import crypto from 'crypto';
 
app.post('/api/paynode-webhook', (req, res) => {
  const payload = JSON.stringify(req.body);
  const signature = req.headers['X-402-Signature'];
  
  const expected = `sha256=${
    crypto.createHmac('sha256', process.env.WEBHOOK_SECRET)
      .update(payload)
      .digest('hex')
  }`;
  
  if (signature !== expected) {
    return res.status(401).json({ error: 'Invalid signature' });
  }
  
  // ✅ Verified — process the event
  const { data } = req.body;
  console.log(`Payment ${data.txHash} received: ${data.amount} from ${data.payer}`);
  res.status(200).json({ received: true });
});

import hmac, hashlib, json
 
@app.post("/api/paynode-webhook")
async def webhook(request: Request):
    body = await request.body()
    signature = request.headers.get("X-402-Signature", "")
    
    expected = "sha256=" + hmac.new(
        WEBHOOK_SECRET.encode(), body, hashlib.sha256
    ).hexdigest()
    
    if not hmac.compare_digest(signature, expected):
        return JSONResponse(status_code=401, content={"error": "Invalid signature"})
    
    # ✅ Verified
    data = json.loads(body)["data"]
    print(f"Payment {data['txHash']}: {data['amount']} from {data['payer']}")
    return {"received": True}