Document in upload

uploadAJAX.js

var someFunctionToUse = function (obj) {
    // Form data    
    var formData = new FormData();
    // Appending the files data in form data 
    formData.append("doc_file", document.getElementById("upload_input_id").files[0]);
    // (Example) attribute from an object
    formData.append("data_filed_name", obj.getAttribute("object_attribute_name"));
    // Creating the Request object
    var oReq = new XMLHttpRequest();
    // Creating event
    oReq.onreadystatechange = function () {
        // Checking the ready state and response
        if (this.readyState == 4 && this.status == 200) {
            let response = JSON.parse(this.response);
            // Checking the resposne (Example)
            if (response["status"] == "success") {
                location.reload();
            } else {
                console.log(response, " ", response.status)
            }

        }
    };
    // Creating the POST request and with async
    oReq.open("POST", "/someURL", true);
    // Sending the request
    oReq.send(formData);
};