# Execution model

When a webhook hits your integration's endpoint, Studio runs your JavaScript with the details of that request available to it. Your code inspects the request and **returns a message object**, which Studio delivers as a push notification.

```
HTTP request ─► your code reads it ─► your code returns a message ─► JustPush delivers it
```

## The incoming request

Your code receives the incoming webhook as a `request` object with these parts:

| Property          | Description                                               |
| ----------------- | --------------------------------------------------------- |
| `request.method`  | The HTTP method — `GET`, `POST`, `PUT`, or `DELETE`.      |
| `request.headers` | The request headers as a key/value object.                |
| `request.body`    | The parsed request body (JSON, when the payload is JSON). |
| `request.query`   | Query-string parameters from the URL, if any.             |

## Returning a message

To send a notification, **return a message object**. At minimum it needs a `title`:

```javascript
return {
    title: "Build passed",
    message: "main is green ✅",
    topic: "CI"
}
```

The full set of fields you can return — priority, sound, images, buttons, and more — is documented in [The message object](/introduction/justpush-studio/writing-code/the-message-object.md) and the [Message schema](/introduction/justpush-studio/reference/message-schema.md).

## Not every request needs a notification

If a request shouldn't produce a notification (for example, a webhook event you don't care about), simply **don't return a message**:

```javascript
if (request.body.event !== "deployment.finished") {
    return // ignore everything else — no push sent
}

return {
    title: "Deployment finished",
    message: request.body.environment
}
```

## Debugging a run

Use `console.log(...)` anywhere in your code. The output is captured per request and shown in the **Console** tab of [Request history](/introduction/justpush-studio/testing-and-monitoring/request-history.md). See [Logging & debugging](/introduction/justpush-studio/writing-code/logging-and-debugging.md).

> **Next:** [The message object](/introduction/justpush-studio/writing-code/the-message-object.md) — every field you can return.


---

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