> ## Documentation Index
> Fetch the complete documentation index at: https://docs.exowizz.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> Learn how Exo webhooks notify external services when your data changes.

Webhooks are the next step after Resource creation. A Resource defines trigger events, and Exo delivers those events to subscribed URLs.

## What are webhooks?

Think of webhooks as "reverse API calls." Instead of an external service asking your app for updates, your app tells the external service when something happens.

For example, when a new order is created in your app, Exo can automatically notify:

* A Zapier workflow that sends a Slack message
* A Make scenario that updates a spreadsheet
* An n8n workflow that creates an invoice

## Triggers

Each Resource defines which trigger events it responds to. Built-in trigger values are:

| Trigger     | When it fires                 |
| ----------- | ----------------------------- |
| `on_create` | A new record is created       |
| `on_update` | An existing record is updated |
| `on_delete` | A record is deleted           |

You define triggers in your resource class:

```php theme={null}
public function triggers(): array
{
    return ['on_create', 'on_update', 'on_delete'];
}
```

You can include any combination. For example, if you only want to notify when records are created:

```php theme={null}
public function triggers(): array
{
    return ['on_create'];
}
```

## How webhook delivery works

When a trigger fires, here's what happens:

1. Exo detects the model event (created, updated, or deleted)
2. It finds all webhook subscriptions that match the resource and event
3. For each matching subscription, Exo dispatches a background job
4. The job sends an HTTP POST to the subscriber's URL with the event data
5. The payload includes an HMAC signature so the receiver can verify it's authentic

<Note>
  Webhooks are delivered via Laravel's queue system. Make sure you have a queue worker running (`php artisan queue:work`) for webhooks to be sent.
</Note>

## Webhook payload

Every webhook delivery sends a JSON payload like this:

```json theme={null}
{
  "event": "on_create",
  "resource": "order",
  "event_id": "01JT1M2X3B2W3PW8ZAF2X36JMY",
  "delivery_id": "01JT1M2Y9HF38TEHSEK5EN9V5C",
  "data": {
    "id": 42,
    "order_number": "ORD-001",
    "status": "pending",
    "total": 49.99,
    "customer_name": "Jane Smith",
    "created_at": "2026-03-28T14:30:00+00:00"
  },
  "timestamp": "2026-03-28T14:30:00.123456Z"
}
```

The `data` field contains the output of your Resource's `transform` method. The payload also includes `event_id` and `delivery_id` for traceability.

## Ownership and webhooks

Webhook subscriptions respect the same ownership rules as the API:

* **Admins** receive webhooks for all records, regardless of owner
* **Regular users** only receive webhooks for records they own (based on the resource's `ownerColumn`)

This means if User A subscribes to `on_create` for orders, they only receive webhooks for orders where `user_id` matches their ID.

## Custom webhook queue

By default, webhook delivery jobs run on the queue defined in `config('exo.queue')`. You can override this per Resource:

```php theme={null}
public function webhookQueue(): ?string
{
    return 'webhooks';
}
```

Return `null` to use the default queue.

You can also override max attempts and backoff per Resource with `webhookMaxAttempts()` and `webhookBackoff()`.