Check whether the current user has permission to create promoted site page

spcancreatepromtepage.js

//Check whether the current user has permission to create promoted site page
getRequest("https://domain.sharepoint.com/sites/name/_api/sitepages/cancreatepromotedpage").then(function(output) {
    var cancreatepage = JSON.parse(output.response);    
    if (cancreatepage) {
        window.location.href = "https://domain.sharepoint.com/sites/name/_layouts/15/CreateSitePage.aspx?promotedState=1";
    } else {
        alert("You didn't have permission to create promotes news post site page");
    }
});

//getRequest method reference
//https://gist.github.com/ktskumar/a9e9df497673e9fd26ead8532b9ff425
function getRequest(url) {
    var request = new XMLHttpRequest();
    return new Promise(function(resolve, reject) {
        request.onreadystatechange = function() {
            if (request.readyState !== 4) return;
            if (request.status >= 200 && request.status < 300) {
                resolve(request);
            } else {
                reject({
                    status: request.status,
                    statusText: request.statusText
                });
            }
        };

        request.open('GET', url, true);
        request.setRequestHeader("Content-Type", "application/json;charset=utf-8");
        request.setRequestHeader("ACCEPT", "application/json; odata.metadata=minimal");       
        request.setRequestHeader("ODATA-VERSION", "4.0");
        request.send();

    });
}
//Author: Shantha Kumar T
//Web: https://www.ktskumar.com