{
    "order_id": ["required", "positive_integer"],
    "products": ["required", { "list_of_different_objects": [
        "product_type", {
            "material": {
                "product_type": "required",
                "material_id": ["required", "positive_integer"],
                "quantity": ["required", {"min_number": 1} ],
                "warehouse_id": "positive_integer"
            },
            "service": {
                "product_type": "required",
                "name": ["required", {"max_length": 10} ]
            }
        }
    ]}],
    "empty_list": ["required", { "list_of_different_objects": [
        "item_type", {
            "string": {
                "value": "required"
            },
            "number": {
                "value": ["required", "integer" ]
            }
        }
    ]}]
}