TownHall Webhooks API

// Webhook signature verification (Node.js)
const crypto = require('crypto');

function verifyWebhook(payload, signature, secret) {
  const expectedSignature = crypto
    .createHmac('sha256', secret)
    .update(payload)
    .digest('hex');
  
  return signature === `sha256=${expectedSignature}`;
}

// Express webhook handler
app.post('/webhook', (req, res) => {
  const signature = req.headers['x-townhall-signature'];
  const payload = JSON.stringify(req.body);
  
  if (!verifyWebhook(payload, signature, process.env.WEBHOOK_SECRET)) {
    return res.status(401).send('Invalid signature');
  }
  
  // Process the submission
  const { form, submission } = req.body;
  console.log('New submission:', submission.data);
  
  res.status(200).send('OK');
});