XMLHttpRequest chunked response, only read last response in progress

Question

I\'m sending chunked data from a NodeJS application back to the browser. The chunks are really json strings. Problem I\'m having is that every time the onprogress

Answer 1

This index based approach works for me:

var last_index = 0;
var xhr = new XMLHttpRequest();
xhr.open("GET", "/servers/scan");
xhr.onprogress = function () {
    var curr_index = xhr.responseText.length;
    if (last_index == curr_index) return; 
    var s = xhr.responseText.substring(last_index, curr_index);
    last_index = curr_index;
    console.log("PROGRESS:", s);
};
xhr.send();

Inspired by https://friendlybit.com/js/partial-xmlhttprequest-responses/