How to use sometimes rule in Laravel 5 request class

Question

I have the following request class:

Answer 1

You can attach a sometimes() rule by overriding the getValidatorInstance() function in your form request:

protected function getValidatorInstance(){
    $validator = parent::getValidatorInstance();

    $validator->sometimes('dob', 'valid_date', function($input)
    {
        return apply_regex($input->dob) === true;
    });

    return $validator;
}