root/trunk/index.php

<?

function getData($url) {
    // caching goes here
    return file_get_contents($url);
}

$baseurl = "http://mybustracker.co.uk/";
$method = $_GET['method'];

switch ($method) {
case "bustracker.departures.getNext":
    include("bustracker.departures.getNext.php");
    break;
default:
    include("default.php");
}

?>