JS for file upload progress with gp.fileupload and Nginx module

gistfile1.js

function pollGp() {
	$.ajax({
		type: 'GET',
		url: '/gp.fileupload.stat/${c.upload_id}',
		cache: false,
		dataType: 'json',
		timeout: 5000,
		success: function(response) {
			if (response.state == 1) {
				$('#progressbar div').css('width', response.percent + '%');
			}
		}
	});
}

function pollNginx() {
	$.ajax({
		type: 'GET',
		url: '/nginx_upload',
		data: {'X-Progress-ID': ${c.upload_id}},
		cache: false,
		dataType: 'json',
		timeout: 5000,
		success: function(response) {
			if (response.state == 'uploading') {
				$('#progressbar div').css('width', (response.received / response.size * 100)  + '%');
			}
		},
		error: pollGp
	});
}

$(document).ready(function() {
	$('form').submit(function() {
		$('<p>Proszę czekać...</p><div id="progressbar"><div></div></div>').appendTo('form');
		$('button').attr('disabled', 'disabled');
		
		window.setInterval(function () {
			pollNginx();
		}, 5000)
		
		return true;
	});
});