JavaScript code to read the latest values from a json file that keeps getting updated every few seconds

I am very new to JavaScript and trying to display the latest values from a .json file that keeps getting updated every 10 seconds into a HTML page. I am reading the file every 10 seconds as well, but I am not getting the latest values from the file. I am getting values which are 50 to 60 seconds older.

I have tried disabling the browser cahche in chrome but stillthe same issue. Can somebody please help on this?

My JavaScript code to read the json file is as follows:

function readJsonFile(callback) {
 var request = new XMLHttpRequest();
 request.open('GET', 'http://localhost:8080/PersonalProject/filename.json');
 request.onload = function() {
  if(request.status>=100 && request.status<=100) {
   //perform some operation
   callback(request.responseText);
  }
  else{
   //perform some operation
   callback('FAILED');
  }
 };
 request.onerror = function() {
  console.error('Connection error');
 };
 request.send();
}


setInterval(function(){
 readJsonFile(function(stat){
  console.log(stat);
 });
}, 10000);