Magento 2 Rest Api as JSON - magento2

Question

i need to return the response of custom web api as JSON.
i need it to be like this:
{
"data": [
{
"id": "1",
"name": "Tiger Nixon",
"position": "System Architect",
"salary": "$320,800",
"start_date": "2011/04/25",
"office": "Edinburgh",
"extn": "5421"
},
{
"id": "2",
"name": "Garrett Winters",
"position": "Accountant",
"salary": "$170,750",
"start_date": "2011/07/25",
"office": "Tokyo",
"extn": "8422"
}
]
}
however, my module is coming out as
[
{
"id": "1",
"name": "Tiger Nixon",
"position": "System Architect",
"salary": "$320,800",
"start_date": "2011/04/25",
"office": "Edinburgh",
"extn": "5421"
},
{
"id": "2",
"name": "Garrett Winters",
"position": "Accountant",
"salary": "$170,750",
"start_date": "2011/07/25",
"office": "Tokyo",
"extn": "8422"
}
]
My Interface is as follows:
<?php
namespace Mag\Rest\Api;
interface OrdersManagementInterface
{
/**
* GET for Stock api
* #param mixed $items
* #return string
*/
public function getOrders();
}
My model is as follows:
<?php
namespace Mag\Rest\Model;
class OrdersManagement
{
public function __construct(
) {
}
/**
* {#inheritdoc}
*/
public function getOrders()
{
//... sql code to get data goes here
$results = $this->connection->fetchAll($sql);
return $response ;
}
}
any idea on how to be able to format the output of the rest api ?