Adding empty array to json object in Angular

Question

Problem Question : I am making call to API and it returns the object back. Now I want to add the empty array to this object and use it in my view. How would i achieve this with angular?

// Controller This works as the data was manually

$scope.deliveryData = [
            {
                productName: 'ProductA ProductA ProductA', quantity: '20', deliveries: []
            },
            {
                productName: 'Product B', quantity: '10', deliveries: []
            }
        ];

// controller This does not work :( how would I add (deliveries:[]) to this ?

 $scope.deliveryData; // This will be now populated from API 
     MyService.delivery()
        .success(function(data){
            $scope.deliveryData= data;
            console.log(data) //this data does not contain the empty array, how i append to it?
        })
        .error(function(status,data){
            console.log(status);
            console.log(data);
        })

I don't know how to achieve this in angular, even I don't know if I am doing this right way. Please give me any suggestions.

UPDATE 1

 .success(function(data){
                $scope.deliveryData = data;
                console.log("Before Change");
                console.log($scope.deliveryData);
                for (var i = 0; i < $scope.deliveryData.length; i++) {
                    $scope.deliveryData[i].deliveries = [];
                }
                console.log("After Change");
                console.log($scope.deliveryData);
            })

Data coming from API in following format:

-Object {delivery: Array[1]}
 --delivery: Array[1]
   ---0:Object
   ----name: "ProductA ProductA ProductA"
   ----quantity: 14 

Answer 1

To add {deliveries: []} to each product item, here is what you should do:

    .success(function(data){
        $scope.deliveryData = data.delivery;
        for (var i = 0; i < $scope.deliveryData.length; i++) {
            $scope.deliveryData[i].deliveries = [];
        }
    })

---

UPDATE

It's basic stuff, there's no way it doesn't work, see it here:

var $scope = {};

$scope.deliveryData = [ // no deliveries here
    {productName: 'ProductA ProductA ProductA', quantity: '20'},
    {productName: 'Product B', quantity: '10'}
];

for (var i = 0; i < $scope.deliveryData.length; i++) {
    $scope.deliveryData[i].deliveries = [];
}

document.getElementsByTagName('pre')[0].innerHTML = JSON.stringify($scope, null, '\t');

<pre></pre>