Laravel验证数组输入

$rules = [
    'slides' => 'required|array',
    'slides.*.name' => 'required',
    'slides.*.resources.*.uuid' =>          
        'required|exists:resources,uuid'
];

//input

{
    'slides': [
        {
            'name': 'slide1',
            'resources': [
                {
                    'uuid': 'blahblah',
                }, // repeat as necessary
            ]
        }, // repeat as necessary
    ]
}

public function rules()
    {
        return [
            'message'=>'required',
            'action_url'=>'sometimes|required',
            'to_users'=>'required|array',
            'to_users.*'=>'required|email',
        ];
    }