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

# From Data to Resource

> Learn how to transform Laravel Data objects into JSON API resources

A data object will automatically be transformed to a JSON response when returned in a controller:

```php theme={null}
class SongController
{
    public function show(Song $model)
    {
        return SongData::from($model);
    }
}
```

The JSON response:

```json theme={null}
{
    "name": "Never gonna give you up",
    "artist": "Rick Astley"
}
```

## Collections

Returning a data collection from the controller:

```php theme={null}
SongData::collect(Song::all());
```

Will return a collection automatically transformed to JSON:

```json theme={null}
[
    {
        "name": "Never Gonna Give You Up",
        "artist": "Rick Astley"
    },
    {
        "name": "Giving Up on Love",
        "artist": "Rick Astley"
    }
]
```

## Paginators

It is also possible to provide a paginator:

```php theme={null}
SongData::collect(Song::paginate());
```

The data object is smart enough to create a paginated response with links to the next, previous, last pages:

```json theme={null}
{
    "data": [
        {
            "name": "Never Gonna Give You Up",
            "artist": "Rick Astley"
        },
        {
            "name": "Giving Up on Love",
            "artist": "Rick Astley"
        }
    ],
    "meta": {
        "current_page": 1,
        "first_page_url": "https://spatie.be/?page=1",
        "from": 1,
        "last_page": 7,
        "last_page_url": "https://spatie.be/?page=7",
        "next_page_url": "https://spatie.be/?page=2",
        "path": "https://spatie.be/",
        "per_page": 15,
        "prev_page_url": null,
        "to": 15,
        "total": 100
    }
}
```

## Transforming Empty Objects

When creating a new model, you probably want to provide a blueprint to the frontend with the required data to create a model:

```json theme={null}
{
    "name": null,
    "artist": null
}
```

Instead of making each property nullable, you can return an empty representation:

```php theme={null}
class SongsController
{
    public function create(): array
    {
        return SongData::empty();
    }
}
```

### Default Values

You can provide default values in the constructor:

```php theme={null}
class SongData extends Data
{
    public function __construct(
        public string $title = 'Title of the song here',
        public string $artist = "An artist",
    ) {
    }
}
```

Or pass defaults within the `empty` call:

```php theme={null}
SongData::empty([
    'name' => 'Title of the song here',
    'artist' => 'An artist'
]);
```

Filter properties in the empty response:

```php theme={null}
SongData::empty(only: ['name']); // Will only return the `name` property
SongData::empty(except: ['name']); // Will return the `artist` property
```

## Response Status Code

When a resource is returned from a controller, the status code will automatically be set to `201 CREATED` when Laravel Data detects that the request's method is `POST`. In all other cases, `200 OK` will be returned.

## Resource Classes

To make it clearer that a data object is a resource, you can use the `Resource` class instead of the `Data` class:

```php theme={null}
use Spatie\LaravelData\Resource;

class SongResource extends Resource
{
    public function __construct(
        public string $title,
        public string $artist,
    ) {
    }
}
```

<Note>
  Resource classes won't validate data or check authorization. They are only used to transform data which makes them faster.
</Note>