PATCH request and nullable fields

[leon0399]

How do y'all handle your PATCH requests with nullable fields?

What I mean:

In PATCH conventionally, these requests should behave differently:

1. Should set both title and artist to null.

{
  "data": {
    "title": null, 
    "artist": null
  }
}

2. Should set artist to null and leave title as-is.

{
  "data": {
    "artist": null,
  }
}

With standard Laravel FormRequests, it is pretty easy: just do $model->update($validated)

But with DTOs this wouldn't work:

class SongData extends Data
{
    public function __construct(
        public ?string $title,
        public ?string $artist,
    ) {
    }
    
    public static function rules(): array
    {
        return [
            'title' => ['nullable', 'string'],
            'artist' => ['nullable', 'string'],
        ];
    }
}

dd($songData->title); // is it null because it explicitly requested as null, or because it wasn't in request?