/mod/lti/servicelib.php
PHP | 300 lines | 195 code | 61 blank | 44 comment | 29 complexity | 7b32b87d4c04fb834bd10c64161d6868 MD5 | raw file
- <?php
- // This file is part of Moodle - http://moodle.org/
- //
- // Moodle is free software: you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation, either version 3 of the License, or
- // (at your option) any later version.
- //
- // Moodle is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
- /**
- * Utility code for LTI service handling.
- *
- * @package mod_lti
- * @copyright Copyright (c) 2011 Moodlerooms Inc. (http://www.moodlerooms.com)
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @author Chris Scribner
- */
- defined('MOODLE_INTERNAL') || die;
- require_once($CFG->dirroot.'/mod/lti/OAuthBody.php');
- // TODO: Switch to core oauthlib once implemented - MDL-30149.
- use moodle\mod\lti as lti;
- define('LTI_ITEM_TYPE', 'mod');
- define('LTI_ITEM_MODULE', 'lti');
- define('LTI_SOURCE', 'mod/lti');
- function lti_get_response_xml($codemajor, $description, $messageref, $messagetype) {
- $xml = new SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?><imsx_POXEnvelopeResponse />');
- $xml->addAttribute('xmlns', 'http://www.imsglobal.org/services/ltiv1p1/xsd/imsoms_v1p0');
- $headerinfo = $xml->addChild('imsx_POXHeader')->addChild('imsx_POXResponseHeaderInfo');
- $headerinfo->addChild('imsx_version', 'V1.0');
- $headerinfo->addChild('imsx_messageIdentifier', (string)mt_rand());
- $statusinfo = $headerinfo->addChild('imsx_statusInfo');
- $statusinfo->addchild('imsx_codeMajor', $codemajor);
- $statusinfo->addChild('imsx_severity', 'status');
- $statusinfo->addChild('imsx_description', $description);
- $statusinfo->addChild('imsx_messageRefIdentifier', $messageref);
- $incomingtype = str_replace('Response', 'Request', $messagetype);
- $statusinfo->addChild('imsx_operationRefIdentifier', $incomingtype);
- $xml->addChild('imsx_POXBody')->addChild($messagetype);
- return $xml;
- }
- function lti_parse_message_id($xml) {
- if (empty($xml->imsx_POXHeader)) {
- return '';
- }
- $node = $xml->imsx_POXHeader->imsx_POXRequestHeaderInfo->imsx_messageIdentifier;
- $messageid = (string)$node;
- return $messageid;
- }
- function lti_parse_grade_replace_message($xml) {
- $node = $xml->imsx_POXBody->replaceResultRequest->resultRecord->sourcedGUID->sourcedId;
- $resultjson = json_decode((string)$node);
- $node = $xml->imsx_POXBody->replaceResultRequest->resultRecord->result->resultScore->textString;
- $score = (string) $node;
- if ( ! is_numeric($score) ) {
- throw new Exception('Score must be numeric');
- }
- $grade = floatval($score);
- if ( $grade < 0.0 || $grade > 1.0 ) {
- throw new Exception('Score not between 0.0 and 1.0');
- }
- $parsed = new stdClass();
- $parsed->gradeval = $grade;
- $parsed->instanceid = $resultjson->data->instanceid;
- $parsed->userid = $resultjson->data->userid;
- $parsed->launchid = $resultjson->data->launchid;
- $parsed->typeid = $resultjson->data->typeid;
- $parsed->sourcedidhash = $resultjson->hash;
- $parsed->messageid = lti_parse_message_id($xml);
- return $parsed;
- }
- function lti_parse_grade_read_message($xml) {
- $node = $xml->imsx_POXBody->readResultRequest->resultRecord->sourcedGUID->sourcedId;
- $resultjson = json_decode((string)$node);
- $parsed = new stdClass();
- $parsed->instanceid = $resultjson->data->instanceid;
- $parsed->userid = $resultjson->data->userid;
- $parsed->launchid = $resultjson->data->launchid;
- $parsed->typeid = $resultjson->data->typeid;
- $parsed->sourcedidhash = $resultjson->hash;
- $parsed->messageid = lti_parse_message_id($xml);
- return $parsed;
- }
- function lti_parse_grade_delete_message($xml) {
- $node = $xml->imsx_POXBody->deleteResultRequest->resultRecord->sourcedGUID->sourcedId;
- $resultjson = json_decode((string)$node);
- $parsed = new stdClass();
- $parsed->instanceid = $resultjson->data->instanceid;
- $parsed->userid = $resultjson->data->userid;
- $parsed->launchid = $resultjson->data->launchid;
- $parsed->typeid = $resultjson->data->typeid;
- $parsed->sourcedidhash = $resultjson->hash;
- $parsed->messageid = lti_parse_message_id($xml);
- return $parsed;
- }
- function lti_accepts_grades($ltiinstance) {
- global $DB;
- $acceptsgrades = true;
- $ltitype = $DB->get_record('lti_types', array('id' => $ltiinstance->typeid));
- if (empty($ltitype->toolproxyid)) {
- $typeconfig = lti_get_config($ltiinstance);
- $typeacceptgrades = isset($typeconfig['acceptgrades']) ? $typeconfig['acceptgrades'] : LTI_SETTING_DELEGATE;
- if (!($typeacceptgrades == LTI_SETTING_ALWAYS ||
- ($typeacceptgrades == LTI_SETTING_DELEGATE && $ltiinstance->instructorchoiceacceptgrades == LTI_SETTING_ALWAYS))) {
- $acceptsgrades = false;
- }
- } else {
- $enabledcapabilities = explode("\n", $ltitype->enabledcapability);
- $acceptsgrades = in_array('Result.autocreate', $enabledcapabilities);
- }
- return $acceptsgrades;
- }
- /**
- * Set the passed user ID to the session user.
- *
- * @param int $userid
- */
- function lti_set_session_user($userid) {
- global $DB;
- if ($user = $DB->get_record('user', array('id' => $userid))) {
- \core\session\manager::set_user($user);
- }
- }
- function lti_update_grade($ltiinstance, $userid, $launchid, $gradeval) {
- global $CFG, $DB;
- require_once($CFG->libdir . '/gradelib.php');
- $params = array();
- $params['itemname'] = $ltiinstance->name;
- $gradeval = $gradeval * floatval($ltiinstance->grade);
- $grade = new stdClass();
- $grade->userid = $userid;
- $grade->rawgrade = $gradeval;
- $status = grade_update(LTI_SOURCE, $ltiinstance->course, LTI_ITEM_TYPE, LTI_ITEM_MODULE, $ltiinstance->id, 0, $grade, $params);
- $record = $DB->get_record('lti_submission', array('ltiid' => $ltiinstance->id, 'userid' => $userid,
- 'launchid' => $launchid), 'id');
- if ($record) {
- $id = $record->id;
- } else {
- $id = null;
- }
- if (!empty($id)) {
- $DB->update_record('lti_submission', array(
- 'id' => $id,
- 'dateupdated' => time(),
- 'gradepercent' => $gradeval,
- 'state' => 2
- ));
- } else {
- $DB->insert_record('lti_submission', array(
- 'ltiid' => $ltiinstance->id,
- 'userid' => $userid,
- 'datesubmitted' => time(),
- 'dateupdated' => time(),
- 'gradepercent' => $gradeval,
- 'originalgrade' => $gradeval,
- 'launchid' => $launchid,
- 'state' => 1
- ));
- }
- return $status == GRADE_UPDATE_OK;
- }
- function lti_read_grade($ltiinstance, $userid) {
- global $CFG;
- require_once($CFG->libdir . '/gradelib.php');
- $grades = grade_get_grades($ltiinstance->course, LTI_ITEM_TYPE, LTI_ITEM_MODULE, $ltiinstance->id, $userid);
- $ltigrade = floatval($ltiinstance->grade);
- if (!empty($ltigrade) && isset($grades) && isset($grades->items[0]) && is_array($grades->items[0]->grades)) {
- foreach ($grades->items[0]->grades as $agrade) {
- $grade = $agrade->grade;
- if (isset($grade)) {
- return $grade / $ltigrade;
- }
- }
- }
- }
- function lti_delete_grade($ltiinstance, $userid) {
- global $CFG;
- require_once($CFG->libdir . '/gradelib.php');
- $grade = new stdClass();
- $grade->userid = $userid;
- $grade->rawgrade = null;
- $status = grade_update(LTI_SOURCE, $ltiinstance->course, LTI_ITEM_TYPE, LTI_ITEM_MODULE, $ltiinstance->id, 0, $grade);
- return $status == GRADE_UPDATE_OK;
- }
- function lti_verify_message($key, $sharedsecrets, $body, $headers = null) {
- foreach ($sharedsecrets as $secret) {
- $signaturefailed = false;
- try {
- // TODO: Switch to core oauthlib once implemented - MDL-30149.
- lti\handle_oauth_body_post($key, $secret, $body, $headers);
- } catch (Exception $e) {
- $signaturefailed = true;
- }
- if (!$signaturefailed) {
- return $secret; // Return the secret used to sign the message).
- }
- }
- return false;
- }
- /**
- * Validate source ID from external request
- *
- * @param object $ltiinstance
- * @param object $parsed
- * @throws Exception
- */
- function lti_verify_sourcedid($ltiinstance, $parsed) {
- $sourceid = lti_build_sourcedid($parsed->instanceid, $parsed->userid,
- $ltiinstance->servicesalt, $parsed->typeid, $parsed->launchid);
- if ($sourceid->hash != $parsed->sourcedidhash) {
- throw new Exception('SourcedId hash not valid');
- }
- }
- /**
- * 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)) {
- // There can only be one.
- if (count($plugins) > 1) {
- throw new coding_exception('More than one ltisource plugin handler found');
- }
- $data->xml = new SimpleXMLElement($data->body);
- $callback = current($plugins);
- call_user_func($callback, $data);
- return true;
- }
- return false;
- }