/**
* This is the function that actually process log entries and calculate sessions
*
* Calculate and Save all new Sessions of a given User
* starting from a given timestamp.
* Optionally updates a progress_bar
*
* Also Updates User's Aggregates
*
* @param Attendanceregister $register
* @param int $userId
* @param int $fromTime (default 0)
* @param progress_bar optional instance of progress_bar to update
* @return int number of new sessions found
*/
function attendanceregister__build_new_user_sessions($register, $userId, $fromTime = 0, progress_bar $progressbar = null)
{
global $DB;
// Retrieve ID of Course containing Register
$course = attendanceregister__get_register_course($register);
$user = attendanceregister__getUser($userId);
// All Courses where User's activities are tracked (Always contains current Course)
$trackedCoursesIds = attendanceregister__get_tracked_courses_ids($register, $course);
// Retrieve logs entries for all tracked courses, after fromTime
$totalLogEntriesCount = 0;
$logEntries = attendanceregister__get_user_log_entries_in_courses($userId, $fromTime, $trackedCoursesIds, $totalLogEntriesCount);
$sessionTimeoutSeconds = $register->sessiontimeout * 60;
$prevLogEntry = null;
$sessionStartTimestamp = null;
$logEntriesCount = 0;
$newSessionsCount = 0;
$sessionLastEntryTimestamp = 0;
// loop new entries if any
if (is_array($logEntries) && count($logEntries) > 0) {
// Scroll all log entries
foreach ($logEntries as $logEntry) {
$logEntriesCount++;
// On first element, get prev entry and session start, than loop.
if (!$prevLogEntry) {
$prevLogEntry = $logEntry;
$sessionStartTimestamp = $logEntry->timecreated;
continue;
}
// Check if between prev and current log, last more than Session Timeout
// if so, the Session ends on the _prev_ log entry
if ($logEntry->timecreated - $prevLogEntry->timecreated > $sessionTimeoutSeconds) {
$newSessionsCount++;
// Estimate Session ended half the Session Timeout after the prev log entry
// (prev log entry is the last entry of the Session)
$sessionLastEntryTimestamp = $prevLogEntry->timecreated;
$estimatedSessionEnd = $sessionLastEntryTimestamp + $sessionTimeoutSeconds / 2;
// Save a new session to the prev entry
attendanceregister__save_session($register, $userId, $sessionStartTimestamp, $estimatedSessionEnd);
// Update the progress bar, if any
if ($progressbar) {
$msg = get_string('updating_online_sessions_of', 'attendanceregister', fullname($user));
$progressbar->update($logEntriesCount, $totalLogEntriesCount, $msg);
}
// Session has ended: session start on current log entry
$sessionStartTimestamp = $logEntry->timecreated;
}
$prevLogEntry = $logEntry;
}
// If le last log entry is not the end of the last calculated session and is older than SessionTimeout
// create a last session
if ($logEntry->timecreated > $sessionLastEntryTimestamp && time() - $logEntry->timecreated > $sessionTimeoutSeconds) {
$newSessionsCount++;
// In this case logEntry (and not prevLogEntry is the last entry of the Session)
$sessionLastEntryTimestamp = $logEntry->timecreated;
$estimatedSessionEnd = $sessionLastEntryTimestamp + $sessionTimeoutSeconds / 2;
// Save a new session to the prev entry
attendanceregister__save_session($register, $userId, $sessionStartTimestamp, $estimatedSessionEnd);
// Update the progress bar, if any
if ($progressbar) {
$msg = get_string('updating_online_sessions_of', 'attendanceregister', fullname($user));
$progressbar->update($logEntriesCount, $totalLogEntriesCount, $msg);
}
}
}
/// Updates Aggregates, only on new session creation
if ($newSessionsCount) {
attendanceregister__update_user_aggregates($register, $userId);
}
// Finalize Progress Bar
if ($progressbar) {
$a = new stdClass();
$a->fullname = fullname($user);
$a->numnewsessions = $newSessionsCount;
$msg = get_string('online_session_updated_report', 'attendanceregister', $a);
attendanceregister__finalize_progress_bar($progressbar, $msg);
}
return $newSessionsCount;
}
/**
* Updates recorded Sessions of a User
* if User's Register is not Locked
* AND if $recalculation is set
* OR attendanceregister_check_user_sessions_need_update(...) returns true
*
* @param object $register Register instance
* @param int $userId User->id
* @param progress_bar $progressbar optional instance of progress_bar to update
* @param boolean $recalculation true on recalculation: ignore locks and needUpdate check
* @return boolean true if any new session has been found
*/
function attendanceregister_update_user_sessions($register, $userId, progress_bar $progressbar = null, $recalculation = false)
{
// If not running in Recalc,
// check if a Lock exists on this User's Register; if so, exit immediately
if (!$recalculation && attendanceregister__check_lock_exists($register, $userId)) {
// (if a progress bar exists, before exiting reset it)
attendanceregister__finalize_progress_bar($progressbar, get_string('online_session_updated', 'attendanceregister'));
mtrace("Lock found on registerId:{$register->id}, userId:{$userId}. Skip updating.");
return false;
}
// Check if Update is needed
if ($recalculation) {
$lastSessionLogout = 0;
$needUpdate = true;
mtrace("Forced recalc of sessions");
} else {
$lastSessionLogout = 0;
$needUpdate = attendanceregister_check_user_sessions_need_update($register, $userId, $lastSessionLogout);
mtrace("registerId:{$register->id}, userId:{$userId} " . ($needUpdate ? "needs update" : "doesn't need update"));
}
if ($needUpdate) {
// Calculate all new sesssions after that timestamp
$newSessionsFound = attendanceregister__build_new_user_sessions($register, $userId, $lastSessionLogout, $progressbar) > 0;
return $newSessionsFound;
} else {
attendanceregister__finalize_progress_bar($progressbar, get_string('online_session_updated', 'attendanceregister'));
return false;
}
}
