enrol/lti/cartridge.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Generates an XML IMS Cartridge with the details for the given tool
  19  *
  20  * @package    enrol_lti
  21  * @copyright  2016 John Okely <john@moodle.com>
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 require_once(dirname(__FILE__) . '/../../config.php');
  26 require_once($CFG->dirroot . '/lib/weblib.php');
  27
  28 $toolid = null;
  29 $token = null;
  30
  31 $filearguments = get_file_argument();
  32 $arguments = explode('/', trim($filearguments, '/'));
  33 if (count($arguments) >= 2) { // Can put cartridge.xml at the end, or anything really.
  34     list($toolid, $token) = $arguments;
  35 }
  36
  37 $toolid = optional_param('id', $toolid, PARAM_INT);
  38 $token = optional_param('token', $token, PARAM_ALPHANUM);
  39
  40 // Only show the cartridge if the token parameter is correct.
  41 // If we do not compare with a shared secret, someone could very easily
  42 // guess an id for the enrolment.
  43 if (!\enrol_lti\helper::verify_cartridge_token($toolid, $token)) {
  44     throw new \moodle_exception('incorrecttoken', 'enrol_lti');
  45 }
  46
  47 $tool = \enrol_lti\helper::get_lti_tool($toolid);
  48
  49 if (!is_enabled_auth('lti')) {
  50     throw new \moodle_exception('pluginnotenabled', 'auth', '', get_string('pluginname', 'auth_lti'));
  51
  52 } else if (!enrol_is_enabled('lti')) {
  53     throw new \moodle_exception('enrolisdisabled', 'enrol_lti');
  54
  55 } else if ($tool->status != ENROL_INSTANCE_ENABLED) {
  56     throw new \moodle_exception('enrolisdisabled', 'enrol_lti');
  57
  58 } else {
  59     header('Content-Type: text/xml; charset=utf-8');
  60     echo \enrol_lti\helper::create_cartridge($toolid);
  61 }