Basic Promise in Javascript

promise.js

    $(document).ready(function () {
                fetchData(url, postdata).then(function (data) {
                   //handle data
                });
    });
    function fetchData(links, apiCount) {
        return new Promise(function (resolve, reject) {
            $.ajax({
                type: "POST",
                url: 'url.php',
                data: {
                    "data1": val1,
                    "data2": val2
                },
                success: function (data) {
                    resolve(data);
                },
                error: function (jqXHR, exception) {
                    reject(jqXHR.status);
                }
            });
        });
    }