Laravel how to validation with unique JSON fields type?

I have a POST endpoint on my Laravel 5.7 API and Mariadb 10.3, I used postman to test my route and here is the problem. I want to send an array of the same kind of object, like this :

{  
   "Shops":[  
   {
     "name": {
        "en":"ShopEng",
        "es":"ShopESP"
      },
    "code": "0891"
   }
   ]
}

In my database.I have Shops table and Name field as JSON type.

{"en":"TestEng","es":"TestESP"}

In my Request. I also tried with the simple but not work.

public function rules()
    {
        return array(
            'Shop'         => 'required|array',
            'Shop.*.name.en' => 'required|unique:shops,name->en',
            'Shop.*.name.es' => 'required|unique:shops,name->es',
            'code'        => 'required|integer'
        );

    }

via Chebli Mohamed