> ## 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.

# Eloquent Casting

> Use Laravel Data objects as Eloquent casts for seamless model integration

Since data objects can be created from arrays and easily transformed back to arrays, they work excellently with [Eloquent casts](https://laravel.com/docs/eloquent-mutators#custom-casts).

## Basic Usage

Cast a model attribute to a data object:

```php theme={null}
class Song extends Model
{
    protected $casts = [
        'artist' => ArtistData::class,
    ];
}
```

Store a data object in a model:

```php theme={null}
Song::create([
    'artist' => new ArtistData(name: 'Rick Astley', age: 22),
]);
```

Or use an array representation:

```php theme={null}
Song::create([
    'artist' => [
        'name' => 'Rick Astley',
        'age' => 22
    ]
]);
```

Retrieve the data object:

```php theme={null}
Song::findOrFail($id)->artist; // ArtistData object
```

## Abstract Data Objects

Use abstract parent data objects with multiple child implementations:

```php theme={null}
abstract class RecordConfig extends Data
{
    public function __construct(
        public int $tracks,
    ) {}
}

class CdRecordConfig extends RecordConfig
{
    public function __construct(
        int $tracks,
        public int $bytes,
    ) {
        parent::__construct($tracks);
    }
}

class VinylRecordConfig extends RecordConfig
{
    public function __construct(
        int $tracks,
        public int $rpm,
    ) {
        parent::__construct($tracks);
    }
}
```

Cast to an abstract data class:

```php theme={null}
class Record extends Model
{
    protected $casts = [
        'config' => RecordConfig::class,
    ];
}
```

Store either child type:

```php theme={null}
$cdRecord = Record::create([
    'config' => new CdRecordConfig(tracks: 12, bytes: 1000),
]);

$vinylRecord = Record::create([
    'config' => new VinylRecordConfig(tracks: 12, rpm: 33),
]);

$cdRecord->config; // CdRecordConfig object
$vinylRecord->config; // VinylRecordConfig object
```

### Database Storage Format

Child data objects are stored with type information:

```json theme={null}
{
    "type": "\\App\\Data\\CdRecordConfig",
    "data": {
        "tracks": 12,
        "bytes": 1000
    }
}
```

### Abstract Data with Collections

Cast collections of abstract data objects:

```php theme={null}
class Record extends Model
{
    protected $casts = [
        'configs' => DataCollection::class . ':' . RecordConfig::class,
    ];
}
```

### Morph Maps

Prevent class name changes from breaking your application:

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

app(DataConfig::class)->enforceMorphMap([
    'cd_record_config' => CdRecordConfig::class,
    'vinyl_record_config' => VinylRecordConfig::class,
]);
```

## Casting Data Collections

Store collections of data objects:

```php theme={null}
class Artist extends Model
{
    protected $casts = [
        'songs' => DataCollection::class.':'.SongData::class,
    ];
}
```

Create with data objects or arrays:

```php theme={null}
Artist::create([
    'songs' => [
        new SongData(title: 'Never gonna give you up', artist: 'Rick Astley'),
        new SongData(title: 'Together Forever', artist: 'Rick Astley'),
    ],
]);

// Or with arrays
Artist::create([
    'songs' => [
        ['title' => 'Never gonna give you up', 'artist' => 'Rick Astley'],
        ['title' => 'Together Forever', 'artist' => 'Rick Astley']
    ],
]);
```

## Default Values for Null

Instantiate data objects with defaults when database value is null:

```php theme={null}
class Song extends Model
{
    protected $casts = [
        'artist' => ArtistData::class . ':default',
    ];
}
```

Define default values in the data class:

```php theme={null}
class ArtistData extends Data 
{
    public string $name = 'Default name';
}
```

```php theme={null}
Song::findOrFail($id)->artist->name; // 'Default name'
```

### Nullable Collections

Always return a DataCollection even when null:

```php theme={null}
class Artist extends Model
{
    protected $casts = [
        'songs' => DataCollection::class.':'.SongData::class.',default',
    ];
}
```

```php theme={null}
$artist = Artist::create([
    'songs' => null
]);

$artist->songs; // DataCollection
$artist->songs->count(); // 0
```

## Encryption

Encrypt data objects and collections automatically:

```php theme={null}
class Artist extends Model
{
    protected $casts = [
        'songs' => DataCollection::class.':'.SongData::class.',encrypted',
    ];
}
```

Data is encrypted when stored and decrypted when retrieved automatically.