CORS POLICY ISSUE : Unable to call REST API using custom Javascript Ajax and Httpget method

[Javoraqa]

Hi Team,

I am trying to get list of all jobs on click of button using its Public API in Splunk dashboard but i am getting CORS policy issue. The same when called using POSTMAN i am getting list of jobs but not in splunk.
Below are the methods which are already implemented :-

----------server.conf -----------

[httpServer]
crossOriginSharingPolicy = *
crossOriginSharingHeaders = *
allowBasicAuth = true

[general]
listenOnIPv6 = yes

( 1  )---------------------JS CODE-------------------

console.log('Check require !');
require([
"jquery",
"splunkjs/mvc/searchmanager",
"splunkjs/mvc/simplexml/ready!"
], function(
$, SearchManager
) {
var auth_token ="****";
$(".button1").on("click", function (){
console.log('1234567890');
var settings = {
"crossDomain": true,
"url": "https://********************/api/2.0/jobs/runs/list",
"contentType": "application/x-www-form-urlencoded;charset=utf-8",
"method": "GET",
"headers": {
"Authorization": "Bearer ****",
"Access-Control-Allow-Origin": "*",
"Access-Control-Allow-Methods" : "GET,POST,PUT,DELETE,OPTIONS",
"Access-Control-Allow-Headers": "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With"
}
}

$.ajax(settings).done(function (response) {
console.log(response);
});
});
});

( 2  )---------------------ERROR-------------------

Access to XMLHttpRequest at 'https://************/api/2.0/jobs/runs/list?_=2839475543271' from origin 'http://host.example.com:8000' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

-----------------------------------------------

Need an immediate help on above issue ? please help
@thambisetty, @ITWhisperer ,  @niketn , @gcusello , @isoutamo ,  @woodcock 

[Javoraqa]

Can someone please help on above issue , as this is a roadblocker ?