filling from-route-parameters.md

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Filling properties from route parameters	9

When creating data objects from requests, it's possible to automatically fill data properties from request route parameters, such as route models.

Filling properties from a route parameter

The FromRouteParameter attribute allows filling properties with route parameter values.

Using simple (scalar) route parameters

Route::patch('/songs/{songId}', [SongController::class, 'update']);

class SongData extends Data {
    #[FromRouteParameter('songId')]
    public int $id;
    public string $name;
}

Here, the $id property will be filled with the songId route parameter value (which most likely is a string or integer).

Using Models, objects or arrays as route parameters**

Given that we have a route to create songs for a specific author, and that the {author} route parameter uses route model binding to automatically bind to an Author model:

Route::post('/songs/{author}', [SongController::class, 'store']);

class SongData extends Data {
    public int $id;
    #[FromRouteParameter('author')]
    public AuthorData $author;
}

Here, the $author property will be filled with the author route parameter value, which will be an instance of the Author model. Note that Laravel Data will automatically cast the model to AuthorData.

Filling properties from route parameter properties

The FromRouteParameterProperty attribute allows filling properties with values from route parameter properties. The main difference from FromRouteParameter is that the former uses the full route parameter value, while FromRouteParameterProperty uses a single property from the route parameter.

In the example below we're using route model binding. {song} represents an instance of the Song model. FromRouteParameterProperty automatically attempts to fill the SongData $id property from $song->id.

Route::patch('/songs/{song}', [SongController::class, 'update']);

class SongData extends Data {
    #[FromRouteParameterProperty('song')]
    public int $id;
    public string $name;
}

Using custom property mapping

In the example below, $name property will be filled with $song->title (instead of `$song->name).

Route::patch('/songs/{song}', [SongController::class, 'update']);

class SongData extends Data {
    #[FromRouteParameterProperty('song')]
    public int $id;
    #[FromRouteParameterProperty('song', 'title')]
    public string $name;
}

Nested property mapping

Nested properties ar supported as well. Here, we fill $singerName from $artist->leadSinger->name:

Route::patch('/artists/{artist}/songs/{song}', [SongController::class, 'update']);

class SongData extends Data {
    #[FromRouteParameterProperty('song')]
    public int $id;
    #[FromRouteParameterProperty('artist', 'leadSinger.name')]
    public string $singerName;
}

Other supported route parameter types

FromRouteParameterProperty is compatible with anything that Laravel's data_get() helper supports. This includes most objects and arrays:

// $song = ['foo' => ['bar' => ['baz' => ['qux' => 'Foonderbar!'] ] ] ];

class SongData extends Data {
    #[FromRouteParameterProperty('song', 'bar.baz.qux')]
    public int $title;
}

Route parameters take priority over request body

By default, route parameters take priority over values in the request body. For example, when the song ID is present in the route model as well as request body, the ID from route model is used.

Route::patch('/songs/{song}', [SongController::class, 'update']);

// PATCH /songs/123
// { "id": 321, "name": "Never gonna give you up" }

class SongData extends Data {
    #[FromRouteParameterProperty('song')]
    public int $id;
    public string $name;
}

Here, $id will be 123 even though the request body has 321 as the ID value.

In most cases, this is useful - especially when you need the ID for a validation rule. However, there may be cases when the exact opposite is required.

The above behavior can be turned off by switching the replaceWhenPresentInBody flag off. This can be useful when you intend to allow updating a property that is present in a route parameter, such as a slug:

Route::patch('/songs/{slug}', [SongController::class, 'update']);

// PATCH /songs/never
// { "slug": "never-gonna-give-you-up", "name": "Never gonna give you up" }

class SongData extends Data {
    #[FromRouteParamete('slug', replaceWhenPresentInBody: false )]
    public string $slug;
}

Here, $slug will be never-gonna-give-you-up even though the route parameter value is never.

Using in combination with validation rules

Filling properties from route parameters can be incredibly useful when dealing with validation rules. Some validation rules may depend on a model property that may not be present in the request body.

Example using the Unique validation rule

Using Laravel's unique validation rule, it may be necessary to have the rule ignore a given ID - this is usually the ID of the model being updated

The Data class

use \Spatie\LaravelData\Attributes\FromRouteParameterProperty;

class SongData extends Data
{
    public function __construct(
        #[FromRouteParameterProperty('song')]
        public ?int $id,
        public ?string $external_id,
        public ?string $title,
        public ?string $artist,
    ) {
    }

    public static function rules(array $payload) : array
    {   
        return [
            // Here, $payload['id'] is already filled from the route model, so the following
            // unique rule works as expected - it ignores the current model when validating
            // uniqueness of external_id 
            'external_id' => [Rule::unique('songs')->ignore(Arr::get($payload, 'id'))],
        ];
    }
}

Route & Controller

Route::patch('/songs/{song}', [SongController, 'update']);

// PATCH /songs/123
// { "external_id": "remote_id_321", "name": "Never gonna give you up" }

class SongController extends Controller {

    public function update(Song $song, SongData $data)
    {
        // here, $data is already validated
    }
}