Mage2\Catalog\Requests\ReviewRequest::rules PHP Method

    public function rules()
    {
        if (!Auth::check()) {
            $validateArray['first_name'] = 'required|max:255';
            $validateArray['last_name'] = 'required|max:255';
            $validateArray['email'] = 'required|max:255|email';
        }
        $validateArray['star'] = 'required|max:255';
        $validateArray['comment'] = 'required';
        return $validateArray;
    }