> ## 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.

# Transformers

> Control which fields appear in API responses and webhook payloads.

The `transform` method defines what data your resource returns. Every time Exo sends an API response or delivers a webhook, it calls `transform` to build the payload.

## Basic transform

Return an array of the fields you want to expose:

```php theme={null}
public function transform(Model $model): array
{
    return [
        'id' => $model->id,
        'name' => $model->name,
        'email' => $model->email,
        'created_at' => $model->created_at,
    ];
}
```

This is the array that API consumers and webhook subscribers receive.

## Choosing which fields to include

You control exactly what gets exposed. A common pattern is to exclude sensitive or internal fields:

```php theme={null}
public function transform(Model $model): array
{
    return [
        'id' => $model->id,
        'order_number' => $model->order_number,
        'status' => $model->status,
        'total' => $model->total,
        'customer_name' => $model->customer_name,
        'created_at' => $model->created_at,
    ];
}
```

<Tip>
  Only include fields that external tools and automations need. Leave out internal data like cost margins, admin notes, or soft-delete timestamps.
</Tip>

## Including related data

You can include data from related models:

```php theme={null}
public function transform(Model $model): array
{
    return [
        'id' => $model->id,
        'name' => $model->name,
        'email' => $model->email,
        'company_name' => $model->company?->name,
        'tags' => $model->tags->pluck('name')->toArray(),
    ];
}
```

<Warning>
  When including relationships, make sure to eager-load them in `baseQuery()` to avoid performance issues. See the [search & queries](/resources/search) page.
</Warning>

## Date formatting

Exo automatically formats date fields as ISO-8601 strings (e.g. `2026-03-28T14:30:00+00:00`). This applies to any attribute listed in the model's `$dates` array or cast as a date.

You don't need to format dates yourself — if you include a date field in your `transform` output and the model recognizes it as a date, Exo handles the formatting through the `resolve` method.

```php theme={null}
public function transform(Model $model): array
{
    return [
        'id' => $model->id,
        'name' => $model->name,
        'created_at' => $model->created_at,  // automatically formatted as ISO-8601
        'updated_at' => $model->updated_at,  // automatically formatted as ISO-8601
    ];
}
```

## Using `toArray` for quick setup

For a quick start, you can return the entire model:

```php theme={null}
public function transform(Model $model): array
{
    return $model->toArray();
}
```

This works but exposes all visible attributes. It's better to explicitly list fields so you control what external tools see — especially if you add new columns to the model later.

<Warning>
  Be careful with `toArray()`. New columns added later can be exposed automatically, including fields you did not intend to publish to external systems.
</Warning>