gistfile1.txt

add_action('wp_ajax_update_shipping', 'update_shipping');
add_action('wp_ajax_nopriv_update_shipping', 'update_shipping');

function update_shipping() {
	// Update shipping
	$dest = array(
		'shipping' => array(
			'postcode' => $_REQUEST['postcode'],
			'country' => $_REQUEST['country']
		)
	);

	ShoppOrder()->Shipping->locate($dest);
	ShoppOrder()->Cart->changed(true);
	ShoppOrder()->Cart->totals();

	echo json_encode(ShoppOrder()->Cart->shipping);
	die;
}