hubspot-webhooks

The saved excerpt is a snapshot from review. The external source remains the complete and most current version.

---
name: hubspot-webhooks
description: >
  Receive and verify HubSpot webhooks. Use when setting up HubSpot webhook
  handlers, debugging X-HubSpot-Signature-v3 signature verification, or
  handling CRM events like contact.creation, contact.propertyChange, or
  deal.creation.
license: MIT
metadata:
  author: hookdeck
  version: "0.1.0"
  repository: https://github.com/hookdeck/webhook-skills
---

# HubSpot Webhooks

## When to Use This Skill

- Setting up HubSpot webhook handlers
- Verifying `X-HubSpot-Signature-v3` headers
- Debugging signature verification failures
- Handling CRM events like contact creation, property changes, or deal events
- Migrating from HubSpot signature v1/v2 to v3

## Essential Code (USE THIS)

HubSpot does not provide an SDK helper for webhook signature verification, so verification is implemented manually with HMAC-SHA256 and base64 across all frameworks.

### HubSpot Signature Verification (JavaScript)

```javascript
const crypto = require('crypto');

const MAX_AGE_MS = 5 * 60 * 1000; // 5 minutes

/**
 * Verify HubSpot v3 webhook signature.
 *
 * Signed content = HTTP method + request URI + raw body + timestamp
 * Signature is HMAC-SHA256 (base64) of that string using the app's Client Secret.
 */
function verifyHubSpotWebhook({ method, uri, rawBody, timestamp, signature, secret }) {
  if (!signature || !timestamp || !secret) return false;

  // Reject stale requests (older than 5 minutes)
  const ts = Number(timestamp);
  if (!Number.isFinite(ts) || Math.abs(Date.now() - ts) > MAX_AGE_MS) return false;

  const body = Buffer.isBuffer(rawBody) ? rawBody.toString('utf8') : rawBody;
  const signedContent = `${method}${uri}${body}${timestamp}`;

  const expected = crypto
    .createHmac('sha256', secret)
    .update(signedContent, 'utf8')
    .digest('base64');

  try {
    return crypto.timingSafeEqual(Buffer.from(expected), Buffer.from(signature));
  } catch {
    return false;
  }
}
```

### Express Webhook Handler

```javascript
const express = require('express');
const app = express();

// CRITICAL: Use express.raw() - HubSpot requires raw body for HMAC verification
app.post('/webhooks/hubspot',
  express.raw({ type: 'application/json' }),
  (req, res) => {
    const signature = req.headers['x-hubspot-signature-v3'];
    const timestamp = req.headers['x-hubspot-request-timestamp'];

    // Reconstruct the full request URI (HubSpot signs the URL it called)
    const uri = `${req.protocol}://${req.get('host')}${req.originalUrl}`;

    const valid = verifyHubSpotWebhook({
      method: req.method,
      uri,
      rawBody: req.body,
      timestamp,
      signature,
      secret: process.env.HUBSPOT_CLIENT_SECRET,
    });

    if (!valid) {
      console.error('HubSpot signature verification failed');
      return res.status(400).send('Invalid signature');
    }

    // HubSpot sends an array of events in each webhook
    const events = JSON.parse(req.body.toString());

    for (const event of events) {
      switch (event.subscriptionType) {
        case 'contact.creation':
          console.log('New contact:', event.objectId);
          break;
        case 'contact.propertyChange':
          console.log('Contact property changed:', event.objectId, event.propertyName);
          break;
        case 'deal.creation':
          console.log('New deal:', event.objectId);
          break;
        default:
          console.log('Unhandled event:', event.subscriptionType);
      }
    }

    res.status(200).send('OK');
  }
);
```

### Python (FastAPI) Signature Verification

```python
import hmac
import hashlib
import base64
import time

MAX_AGE_MS = 5 * 60 * 1000  # 5 minutes

def verify_hubspot_webhook(method: str, uri: str, raw_body: bytes,
                           timestamp: str, signature: str, secret: str) -> bool:
    if not signature or not timestamp or not secret:
        return False

    try:
        ts = int(timestamp)
    except ValueError:
        return False

    if abs(int(time.time() *