XHR upload progress

a.js

var xhr = new XMLHttpRequest();

xhr.upload.addEventListener('progress', function(e) {
	var percent = parseInt(e.loaded / e.total * 100, 10)+'%';
	console.log('progress', percent);
}, false);

xhr.onreadystatechange = function(e) {
	if (xhr.readyState === 4 && xhr.status === 200) {
		console.log('done!');
	}
}

xhr.open('post', '/path/to/upload/script', true);
xhr.send(image);