Your IP : 192.168.165.1
<?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/>.
/**
* This file contains a class definition for the LISResults container resource
*
* @package ltiservice_gradebookservices
* @copyright 2017 Cengage Learning http://www.cengage.com
* @author Dirk Singels, Diego del Blanco, Claude Vervoort
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
namespace ltiservice_gradebookservices\local\resources;
use ltiservice_gradebookservices\local\service\gradebookservices;
use mod_lti\local\ltiservice\resource_base;
defined('MOODLE_INTERNAL') || die();
/**
* A resource implementing LISResult container.
*
* @package ltiservice_gradebookservices
* @copyright 2017 Cengage Learning http://www.cengage.com
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class results extends resource_base {
/**
* Class constructor.
*
* @param \ltiservice_gradebookservices\local\service\gradebookservices $service Service instance
*/
public function __construct($service) {
parent::__construct($service);
$this->id = 'Result.collection';
$this->template = '/{context_id}/lineitems/{item_id}/lineitem/results';
$this->variables[] = 'Results.url';
$this->formats[] = 'application/vnd.ims.lis.v2.resultcontainer+json';
$this->methods[] = 'GET';
}
/**
* Execute the request for this resource.
*
* @param \mod_lti\local\ltiservice\response $response Response object for this request.
*/
public function execute($response) {
global $CFG, $DB;
$params = $this->parse_template();
$contextid = $params['context_id'];
$itemid = $params['item_id'];
$isget = $response->get_request_method() === self::HTTP_GET;
// We will receive typeid when working with LTI 1.x, if not the we are in LTI 2.
$typeid = optional_param('type_id', null, PARAM_INT);
$scope = gradebookservices::SCOPE_GRADEBOOKSERVICES_RESULT_READ;
try {
if (!$this->check_tool($typeid, $response->get_request_data(), array($scope))) {
throw new \Exception(null, 401);
}
$typeid = $this->get_service()->get_type()->id;
if (!($course = $DB->get_record('course', array('id' => $contextid), 'id', IGNORE_MISSING))) {
throw new \Exception("Not Found: Course {$contextid} doesn't exist", 404);
}
if (!$this->get_service()->is_allowed_in_context($typeid, $course->id)) {
throw new \Exception('Not allowed in context', 403);
}
if (!$DB->record_exists('grade_items', array('id' => $itemid))) {
throw new \Exception("Not Found: Grade item {$itemid} doesn't exist", 404);
}
$item = $this->get_service()->get_lineitem($contextid, $itemid, $typeid);
if ($item === false) {
throw new \Exception('Line item does not exist', 404);
}
$gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($itemid);
$ltilinkid = null;
if (isset($item->iteminstance)) {
$ltilinkid = $item->iteminstance;
} else if ($gbs && isset($gbs->ltilinkid)) {
$ltilinkid = $gbs->ltilinkid;
}
if ($ltilinkid != null) {
if (is_null($typeid)) {
if (isset($item->iteminstance) && (!gradebookservices::check_lti_id($ltilinkid, $item->courseid,
$this->get_service()->get_tool_proxy()->id))) {
$response->set_code(403);
$response->set_reason("Invalid LTI id supplied.");
return;
}
} else {
if (isset($item->iteminstance) && (!gradebookservices::check_lti_1x_id($ltilinkid, $item->courseid,
$typeid))) {
$response->set_code(403);
$response->set_reason("Invalid LTI id supplied.");
return;
}
}
}
require_once($CFG->libdir.'/gradelib.php');
switch ($response->get_request_method()) {
case 'GET':
$useridfilter = optional_param('user_id', 0, PARAM_INT);
$limitnum = optional_param('limit', 0, PARAM_INT);
$limitfrom = optional_param('from', 0, PARAM_INT);
$typeid = optional_param('type_id', null, PARAM_TEXT);
$json = $this->get_json_for_get_request($item->id, $limitfrom, $limitnum,
$useridfilter, $typeid, $response);
$response->set_content_type($this->formats[0]);
$response->set_body($json);
break;
default: // Should not be possible.
$response->set_code(405);
$response->set_reason("Invalid request method specified.");
return;
}
$response->set_body($json);
} catch (\Exception $e) {
$response->set_code($e->getCode());
$response->set_reason($e->getMessage());
}
}
/**
* Generate the JSON for a GET request.
*
* @param int $itemid Grade item instance ID
* @param int $limitfrom Offset for the first result to include in this paged set
* @param int $limitnum Maximum number of results to include in the response, ignored if zero
* @param int $useridfilter The user id to filter the results.
* @param int $typeid Lti tool typeid (or null)
* @param \mod_lti\local\ltiservice\response $response The response element needed to add a header.
*
* @return string
*/
private function get_json_for_get_request($itemid, $limitfrom, $limitnum, $useridfilter, $typeid, $response) {
if ($useridfilter > 0) {
$grades = \grade_grade::fetch_all(array('itemid' => $itemid, 'userid' => $useridfilter));
} else {
$grades = \grade_grade::fetch_all(array('itemid' => $itemid));
}
$firstpage = null;
$nextpage = null;
$prevpage = null;
$lastpage = null;
if ($grades && isset($limitnum) && $limitnum > 0) {
// Since we only display grades that have been modified, we need to filter first in order to support
// paging.
$resultgrades = array_filter($grades, function ($grade) {
return !empty($grade->timemodified);
});
// We save the total count to calculate the last page.
$totalcount = count($resultgrades);
// We slice to the requested item offset to insure proper item is always first, and we always return
// first pageset of any remaining items.
$grades = array_slice($resultgrades, $limitfrom);
if (count($grades) > 0) {
$pagedgrades = array_chunk($grades, $limitnum);
$pageset = 0;
$grades = $pagedgrades[$pageset];
}
if ($limitfrom >= $totalcount || $limitfrom < 0) {
$outofrange = true;
} else {
$outofrange = false;
}
$limitprev = $limitfrom - $limitnum >= 0 ? $limitfrom - $limitnum : 0;
$limitcurrent = $limitfrom;
$limitlast = $totalcount - $limitnum + 1 >= 0 ? $totalcount - $limitnum + 1 : 0;
$limitfrom += $limitnum;
$baseurl = new \moodle_url($this->get_endpoint());
if (is_null($typeid)) {
$baseurl->param('limit', $limitnum);
if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
$nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
}
$firstpage = new \moodle_url($baseurl, ['from' => 0]);
$canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
$lastpage = new \moodle_url($baseurl, ['from' => $limitlast]);
if (($limitcurrent > 0) && (!$outofrange)) {
$prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
}
} else {
$baseurl->params(['type_id' => $typeid, 'limit' => $limitnum]);
if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
$nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
}
$firstpage = new \moodle_url($baseurl, ['from' => 0]);
$canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
if (($limitcurrent > 0) && (!$outofrange)) {
$prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
}
}
}
$jsonresults = [];
$lineitem = new lineitem($this->get_service());
$endpoint = $lineitem->get_endpoint();
if ($grades) {
foreach ($grades as $grade) {
if (!empty($grade->timemodified)) {
array_push($jsonresults, gradebookservices::result_for_json($grade, $endpoint, $typeid));
}
}
}
if (isset($canonicalpage) && ($canonicalpage)) {
$links = 'Link: <' . $firstpage->out() . '>; rel=“first”';
if (!is_null($prevpage)) {
$links .= ', <' . $prevpage->out() . '>; rel=“prev”';
}
$links .= ', <' . $canonicalpage->out() . '>; rel=“canonical”';
if (!is_null($nextpage)) {
$links .= ', <' . $nextpage->out() . '>; rel=“next”';
}
$links .= ', <' . $lastpage->out() . '>; rel=“last”';
$response->add_additional_header($links);
}
return json_encode($jsonresults);
}
/**
* Parse a value for custom parameter substitution variables.
*
* @param string $value String to be parsed
*
* @return string
*/
public function parse_value($value) {
global $COURSE, $CFG;
if (strpos($value, '$Results.url') !== false) {
require_once($CFG->libdir . '/gradelib.php');
$resolved = '';
$this->params['context_id'] = $COURSE->id;
$id = optional_param('id', 0, PARAM_INT); // Course Module ID.
if (!empty($id)) {
$cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
$id = $cm->instance;
$item = grade_get_grades($COURSE->id, 'mod', 'lti', $id);
if ($item && $item->items) {
$this->params['item_id'] = $item->items[0]->id;
$resolved = parent::get_endpoint();
}
}
$value = str_replace('$Results.url', $resolved, $value);
}
return $value;
}
}