$modifiedSince = strtotime('07/28/2014 6:10 GMT') * 1000;
$data = array('key' => 'YOUR API KEY', 'modifiedSince' => $modifiedSince, 'includeInactiveItems' => true, 'includeItemsWithQuantityZero' => true);
$data_string = json_encode($data);
$context = stream_context_create(array(
'header' => "Accept: application/json\r\n".
"Content-Type: application/json\r\n",
'content' => $data_string
$result = file_get_contents('http://user.traxia.com/app/api/inventory', false, $context);