/**
* Extend the LTI services through the ltisource plugins
*
* @param stdClass $data LTI request data
* @return bool
* @throws coding_exception
*/
function lti_extend_lti_services($data)
{
$plugins = get_plugin_list_with_function('ltisource', $data->messagetype);
if (!empty($plugins)) {
try {
// There can only be one
if (count($plugins) > 1) {
throw new coding_exception('More than one ltisource plugin handler found');
}
$callback = current($plugins);
call_user_func($callback, $data);
} catch (moodle_exception $e) {
$error = $e->getMessage();
if (debugging('', DEBUG_DEVELOPER)) {
$error .= ' ' . format_backtrace(get_exception_info($e)->backtrace);
}
$responsexml = lti_get_response_xml('failure', $error, $data->messageid, $data->messagetype);
header('HTTP/1.0 400 bad request');
echo $responsexml->asXML();
}
return true;
}
return false;
}
$data->xml = $xml;
$data->messageid = lti_parse_message_id($xml);
$data->messagetype = $messagetype;
$data->consumerkey = $consumerkey;
$data->sharedsecret = $sharedsecret;
$eventdata = array();
$eventdata['other'] = array();
$eventdata['other']['messageid'] = $data->messageid;
$eventdata['other']['messagetype'] = $messagetype;
$eventdata['other']['consumerkey'] = $consumerkey;
// Before firing the event, allow subplugins a chance to handle.
if (lti_extend_lti_services($data)) {
break;
}
// If an event handler handles the web service, it should set this global to true
// So this code knows whether to send an "operation not supported" or not.
global $ltiwebservicehandled;
$ltiwebservicehandled = false;
try {
$event = \mod_lti\event\unknown_service_api_called::create($eventdata);
$event->set_message_data($data);
$event->trigger();
} catch (Exception $e) {
$ltiwebservicehandled = false;
}
if (!$ltiwebservicehandled) {
$responsexml = lti_get_response_xml('unsupported', 'unsupported', lti_parse_message_id($xml), $messagetype);
echo $responsexml->asXML();
}
break;
}
/**
* Echo an exception message encapsulated in XML.
*
* @param \Exception $exception The exception that was thrown
*/
public function handle(\Exception $exception)
{
$message = $exception->getMessage();
// Add the exception backtrace for developers.
if (debugging('', DEBUG_DEVELOPER)) {
$message .= "\n" . format_backtrace(get_exception_info($exception)->backtrace, true);
}
// Switch to response.
$type = str_replace('Request', 'Response', $this->type);
// Build the appropriate xml.
$response = lti_get_response_xml('failure', $message, $this->id, $type);
$xml = $response->asXML();
// Log the request if necessary.
if ($this->log) {
lti_log_response($xml, $exception);
}
echo $xml;
}
