# Commerce Layer Webhooks

## When to Use This Skill

* How do I receive Commerce Layer webhooks?
* How do I verify Commerce Layer webhook signatures?
* How do I handle `orders.place`, `orders.approve`, or `orders.pay` events?
* Why is my Commerce Layer `X-CommerceLayer-Signature` verification failing?
* Setting up a Commerce Layer callback endpoint for order/shipment events

## Verification (core)

Commerce Layer signs the raw request body with HMAC-SHA256 keyed on the
webhook's `shared_secret` and sends the digest as base64 in the
`X-CommerceLayer-Signature` header. The triggering topic is in `X-CommerceLayer-Topic`.
The `shared_secret` is returned once, in the response when you create the webhook
(`POST /api/webhooks`) — it is not the same as your API credentials.

> Read the raw body, NOT the parsed one. Re-serializing parsed JSON changes bytes
> (key order, whitespace) and breaks the signature. Commerce Layer has no SDK verify
> helper, so verify manually (this matches the official docs example).

Node:

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

function verifyCommerceLayerSignature(rawBody, signature, sharedSecret) {
  if (!signature) return false;
  const expected = crypto
    .createHmac('sha256', sharedSecret)
    .update(rawBody) // rawBody is a Buffer/string — never JSON.parse first
    .digest('base64');
  try {
    return crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected));
  } catch {
    return false; // length mismatch = invalid
  }
}

```

Python:

```python
import hmac, hashlib, base64

def verify_commercelayer_signature(raw_body: bytes, signature: str, shared_secret: str) -> bool:
    if not signature:
        return False
    expected = base64.b64encode(
        hmac.new(shared_secret.encode(), raw_body, hashlib.sha256).digest()
    ).decode()
    return hmac.compare_digest(signature, expected)

```

> For complete handlers with route wiring, event dispatch, and tests, see:
> 
> * [examples/express/](https://github.com/hookdeck/webhook-skills/tree/main/skills/commercelayer-webhooks/examples/express/)
> * [examples/nextjs/](https://github.com/hookdeck/webhook-skills/tree/main/skills/commercelayer-webhooks/examples/nextjs/)
> * [examples/fastapi/](https://github.com/hookdeck/webhook-skills/tree/main/skills/commercelayer-webhooks/examples/fastapi/)

## Common Event Types (Topics)

Topics use the format `{resource}.{trigger}`.

| Topic | Triggered When |
| --- | --- |
| `orders.place` | Customer places an order |
| `orders.approve` | Order is approved |
| `orders.cancel` | Order is cancelled |
| `orders.pay` | Order is paid (payment captured) |
| `orders.refund` | Order is refunded |
| `customers.create` | A new customer is created |
| `shipments.ship` | A shipment is shipped |
| `shipments.deliver` | A shipment is delivered |

> Commerce Layer supports 100+ topics across `orders`, `customers`, `shipments`,
> `returns`, `refunds`, `authorizations`, `captures`, `gift_cards`, and more.
> For the full list, see [references/overview.md](https://github.com/hookdeck/webhook-skills/blob/main/skills/commercelayer-webhooks/references/overview.md) and the
> [Commerce Layer webhooks docs](https://docs.commercelayer.io/core/real-time-webhooks).

Payload: JSON:API format, identical to fetching the resource via the REST API —
`{ "data": { "id", "type", "attributes", "relationships" } }`. For `.destroy` topics
only `data.id` is populated (other attributes are `null`).

## Environment Variables

```bash
COMMERCELAYER_SHARED_SECRET=your_webhook_shared_secret   # returned when you create the webhook

```

## Local Development

```bash
# Start tunnel (no account needed)
npx hookdeck-cli listen 3000 commercelayer --path /webhooks/commercelayer

```

## Reliability & Retries

* Your endpoint must return a 2xx status within 5 seconds.
* Failed deliveries are retried up to 10 times.
* After 5 unsuccessful attempts, the organization owner/admins are notified.
* After 30 consecutive failures the webhook's circuit breaker trips
  (`circuit_state` → `open`, tracked via `circuit_failure_count`) and it must be
  reset manually. (`closed` is the healthy default state.)

Verify fast, then do slow work asynchronously so you always answer within 5 seconds.

## Reference Materials

* [references/overview.md](https://github.com/hookdeck/webhook-skills/blob/main/skills/commercelayer-webhooks/references/overview.md) - Commerce Layer webhook concepts and topics
* [references/setup.md](https://github.com/hookdeck/webhook-skills/blob/main/skills/commercelayer-webhooks/references/setup.md) - Create a webhook, get the shared_secret
* [references/verification.md](https://github.com/hookdeck/webhook-skills/blob/main/skills/commercelayer-webhooks/references/verification.md) - Signature verification details and gotchas