That's really bad solution.
In new PrestaShop you should use JsonResponse in your Symfony type controller.
use Symfony\Component\HttpFoundation\JsonResponse;
return new JsonResponse([
"1" => [
"ID" => "123-265",
"ID eshop"=> "System Architect",
"Kategorie"=> "$320,800",
"Počet položek"=> "2011/04/25",
"Kategorie"=> "Edinburgh",
"Podkategorie_1"=> "5421",
"Podkategorie_2"=> "5421",
"Podkategorie_3"=> "5421",
"Počet položek eshop"=> "5421"
]
]
);