How to elegantly modify the KEY of the output JSON in LARAVEL

Question

I have two MODEL

Product:

protected $visible = ['modules', 'id','name'];
public function modules()
    {
        return $this->hasMany('App\Model\Module','root','id');
    }

Module:

protected $visible = [ 'id','name'];

In the controller:

$products = $this->product->with(['modules'])->get();

Output:

The front-end uses iview, I want to use iview's cascade selection
The format requirement is:

So I would like to ask, how can I elegantly modify the json key in LARAVEL to meet my needs?