Quick Guide to Implementing Webhooks in SignNow

Hey there, fellow JavaScript dev! Ready to supercharge your SignNow integration with webhooks? Let's dive right in and get those real-time updates flowing.

Introduction

Webhooks are like your app's personal news reporters, delivering the latest scoop on what's happening in SignNow land. They're crucial for keeping your integration snappy and up-to-date. We'll be using the SignNow API to set these bad boys up, so buckle up!

Prerequisites

Before we start, make sure you've got:

• Your SignNow API credentials (don't forget to keep them secret!)
• A Node.js environment ready to roll
• A solid grasp on RESTful APIs and webhooks (but hey, you're here, so I'm sure you're good)

Setting Up the Webhook Endpoint

First things first, let's create a simple Express.js server to catch those webhook events. Here's a quick snippet to get you started:

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

app.post('/webhook', (req, res) => {
  console.log('Webhook received:', req.body);
  res.sendStatus(200);
});

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

Registering a Webhook with SignNow API

Now, let's tell SignNow where to send those juicy updates. We'll use axios to make this API call:

const axios = require('axios');

async function registerWebhook() {
  try {
    const response = await axios.post('https://api.signnow.com/api/v2/webhooks', {
      event_type: 'document.signed',
      callback_url: 'https://your-server.com/webhook',
      include_data: true
    }, {
      headers: {
        'Authorization': 'Bearer YOUR_ACCESS_TOKEN',
        'Content-Type': 'application/json'
      }
    });
    console.log('Webhook registered:', response.data);
  } catch (error) {
    console.error('Error registering webhook:', error.response.data);
  }
}

registerWebhook();

Handling Webhook Events

SignNow can send various events, like when a document is signed or when a field is updated. Here's how you might handle them:

app.post('/webhook', (req, res) => {
  const { event_type, payload } = req.body;

  switch (event_type) {
    case 'document.signed':
      console.log('Document signed:', payload.document_id);
      // Do something cool with the signed document
      break;
    case 'field.update':
      console.log('Field updated:', payload.field_name);
      // Maybe update your database?
      break;
    // Add more cases as needed
  }

  res.sendStatus(200);
});

Securing Your Webhook

Security first! SignNow sends a signature with each webhook. Let's verify it:

const crypto = require('crypto');

function verifySignature(payload, signature, secret) {
  const hmac = crypto.createHmac('sha256', secret);
  const digest = hmac.update(JSON.stringify(payload)).digest('hex');
  return signature === digest;
}

app.post('/webhook', (req, res) => {
  const signature = req.headers['x-signnow-signature'];
  
  if (!verifySignature(req.body, signature, 'YOUR_WEBHOOK_SECRET')) {
    return res.status(401).send('Invalid signature');
  }

  // Process the webhook...
});

Testing Your Webhook

SignNow provides tools to test your webhook. But for quick checks, you can use a tool like ngrok to expose your local server and simulate events. Give it a shot!

Best Practices

• Always handle errors gracefully. Nobody likes a crashy webhook.
• Implement retry logic for failed webhook deliveries.
• If you're expecting high volume, consider using a queue system.

Troubleshooting Common Issues

Running into trouble? Here are some quick fixes:

• "Webhook not receiving events": Double-check your callback URL and firewall settings.
• "Signature verification failing": Ensure you're using the correct secret and payload.
• "Webhook timing out": Optimize your processing logic or use async responses.

Conclusion

And there you have it! You're now ready to rock the world of SignNow webhooks. Remember, webhooks are powerful tools, so use them wisely and keep your code clean.

Happy coding, and may your integrations be ever responsive!