/**
* Performs the synchronisation of grades.
*
* @return bool|void
*/
public function execute()
{
global $DB, $CFG;
require_once $CFG->dirroot . '/enrol/lti/ims-blti/OAuth.php';
require_once $CFG->dirroot . '/enrol/lti/ims-blti/OAuthBody.php';
require_once $CFG->dirroot . '/lib/completionlib.php';
require_once $CFG->libdir . '/gradelib.php';
require_once $CFG->dirroot . '/grade/querylib.php';
// Check if the authentication plugin is disabled.
if (!is_enabled_auth('lti')) {
mtrace('Skipping task - ' . get_string('pluginnotenabled', 'auth', get_string('pluginname', 'auth_lti')));
return true;
}
// Check if the enrolment plugin is disabled - isn't really necessary as the task should not run if
// the plugin is disabled, but there is no harm in making sure core hasn't done something wrong.
if (!enrol_is_enabled('lti')) {
mtrace('Skipping task - ' . get_string('enrolisdisabled', 'enrol_lti'));
return true;
}
// Get all the enabled tools.
if ($tools = \enrol_lti\helper::get_lti_tools(array('status' => ENROL_INSTANCE_ENABLED, 'gradesync' => 1))) {
foreach ($tools as $tool) {
mtrace("Starting - Grade sync for shared tool '{$tool->id}' for the course '{$tool->courseid}'.");
// Variables to keep track of information to display later.
$usercount = 0;
$sendcount = 0;
// We check for all the users - users can access the same tool from different consumers.
if ($ltiusers = $DB->get_records('enrol_lti_users', array('toolid' => $tool->id), 'lastaccess DESC')) {
$completion = new \completion_info(get_course($tool->courseid));
foreach ($ltiusers as $ltiuser) {
$mtracecontent = "for the user '{$ltiuser->userid}' in the tool '{$tool->id}' for the course " . "'{$tool->courseid}'";
$usercount = $usercount + 1;
// Check if we do not have a serviceurl - this can happen if the sync process has an unexpected error.
if (empty($ltiuser->serviceurl)) {
mtrace("Skipping - Empty serviceurl {$mtracecontent}.");
continue;
}
// Check if we do not have a sourceid - this can happen if the sync process has an unexpected error.
if (empty($ltiuser->sourceid)) {
mtrace("Skipping - Empty sourceid {$mtracecontent}.");
continue;
}
// Need a valid context to continue.
if (!($context = \context::instance_by_id($tool->contextid))) {
mtrace("Failed - Invalid contextid '{$tool->contextid}' for the tool '{$tool->id}'.");
continue;
}
// Ok, let's get the grade.
$grade = false;
if ($context->contextlevel == CONTEXT_COURSE) {
// Check if the user did not completed the course when it was required.
if ($tool->gradesynccompletion && !$completion->is_course_complete($ltiuser->userid)) {
mtrace("Skipping - Course not completed {$mtracecontent}.");
continue;
}
// Get the grade.
if ($grade = grade_get_course_grade($ltiuser->userid, $tool->courseid)) {
$grademax = floatval($grade->item->grademax);
$grade = $grade->grade;
}
} else {
if ($context->contextlevel == CONTEXT_MODULE) {
$cm = get_coursemodule_from_id(false, $context->instanceid, 0, false, MUST_EXIST);
if ($tool->gradesynccompletion) {
$data = $completion->get_data($cm, false, $ltiuser->userid);
if ($data->completionstate != COMPLETION_COMPLETE_PASS && $data->completionstate != COMPLETION_COMPLETE) {
mtrace("Skipping - Activity not completed {$mtracecontent}.");
continue;
}
}
$grades = grade_get_grades($cm->course, 'mod', $cm->modname, $cm->instance, $ltiuser->userid);
if (!empty($grades->items[0]->grades)) {
$grade = reset($grades->items[0]->grades);
if (!empty($grade->item)) {
$grademax = floatval($grade->item->grademax);
} else {
$grademax = floatval($grades->items[0]->grademax);
}
$grade = $grade->grade;
}
}
}
if ($grade === false || $grade === null || strlen($grade) < 1) {
mtrace("Skipping - Invalid grade {$mtracecontent}.");
continue;
}
// No need to be dividing by zero.
if (empty($grademax)) {
mtrace("Skipping - Invalid grade {$mtracecontent}.");
continue;
}
// This can happen if the sync process has an unexpected error.
if ($grade == $ltiuser->lastgrade) {
mtrace("Not sent - The grade {$mtracecontent} was not sent as the grades are the same.");
continue;
}
// Sync with the external system.
$floatgrade = $grade / $grademax;
$body = \enrol_lti\helper::create_service_body($ltiuser->sourceid, $floatgrade);
try {
$response = sendOAuthBodyPOST('POST', $ltiuser->serviceurl, $ltiuser->consumerkey, $ltiuser->consumersecret, 'application/xml', $body);
} catch (\Exception $e) {
mtrace("Failed - The grade '{$floatgrade}' {$mtracecontent} failed to send.");
mtrace($e->getMessage());
continue;
}
if (strpos(strtolower($response), 'success') !== false) {
$DB->set_field('enrol_lti_users', 'lastgrade', intval($grade), array('id' => $ltiuser->id));
mtrace("Success - The grade '{$floatgrade}' {$mtracecontent} was sent.");
$sendcount = $sendcount + 1;
} else {
mtrace("Failed - The grade '{$floatgrade}' {$mtracecontent} failed to send.");
}
}
}
mtrace("Completed - Synced grades for tool '{$tool->id}' in the course '{$tool->courseid}'. " . "Processed {$usercount} users; sent {$sendcount} grades.");
mtrace("");
}
}
}
