xhr_state.js

let url = "https://medium.com/search?q=javascriptjeep";
let request = new XMLHttpRequest();
console.log(request.readyState); // 0
//after calling open the state will be changed to 1

request.open("GET", url);
console.log(request.readyState); // 1

// we need to implement readystatechange event to detect 2,3,4, events
request.onreadystatechange = function() {
    console.log(request.readyState)
    if (request.readyState == 2) {
        console.log("Header received");
    } else if (request.readyState == 3) {
        console.log("loading");
    } else if (request.readyState == 4) {
        console.log("Request Finished");
    } 
};

request.send()