<?php /** * Elgg system log. * Listens to events and writes crud events into the system log database. * * @package Elgg * @subpackage Core * @author Curverider Ltd * @link http://elgg.org/ */ /** * Interface that provides an interface which must be implemented by all objects wishing to be * recorded in the system log (and by extension the river). * * This interface defines a set of methods that permit the system log functions to hook in and retrieve * the necessary information and to identify what events can actually be logged. * * To have events involving your object to be logged simply implement this interface. * * @author Curverider Ltd */ interface Loggable { /** * Return an identification for the object for storage in the system log. * This id must be an integer. * * @return int */ public function getSystemLogID(); /** * Return the class name of the object. * Added as a function because get_class causes errors for some reason. */ public function getClassName(); /** * Return the type of the object - eg. object, group, user, relationship, metadata, annotation etc */ public function getType(); /** * Return a subtype. For metadata & annotations this is the 'name' and for relationship this is the relationship type. */ public function getSubtype(); /** * For a given ID, return the object associated with it. * This is used by the river functionality primarily. * This is useful for checking access permissions etc on objects. */ public function getObjectFromID($id); /** * Return the GUID of the owner of this object. */ public function getObjectOwnerGUID(); } /** * Retrieve the system log based on a number of parameters. * * @param int or array $by_user The guid(s) of the user(s) who initiated the event. * @param string $event The event you are searching on. * @param string $class The class of object it effects. * @param string $type The type * @param string $subtype The subtype. * @param int $limit Maximum number of responses to return. * @param int $offset Offset of where to start. * @param bool $count Return count or not */ function get_system_log($by_user = "", $event = "", $class = "", $type = "", $subtype = "", $limit = 10, $offset = 0, $count = false, $timebefore = 0, $timeafter = 0, $object_id = 0) { global $CONFIG; $by_user_orig = $by_user; if (is_array($by_user) && sizeof($by_user) > 0) { foreach($by_user as $key => $val) { $by_user[$key] = (int) $val; } } else { $by_user = (int)$by_user; } $event = sanitise_string($event); $class = sanitise_string($class); $type = sanitise_string($type); $subtype = sanitise_string($subtype); $limit = (int)$limit; $offset = (int)$offset; $where = array(); if ($by_user_orig!=="") { if (is_int($by_user)) { $where[] = "performed_by_guid=$by_user"; } else if (is_array($by_user)) { $where [] = "performed_by_guid in (". implode(",",$by_user) .")"; } } if ($event != "") { $where[] = "event='$event'"; } if ($class!=="") { $where[] = "object_class='$class'"; } if ($type != "") { $where[] = "object_type='$type'"; } if ($subtype!=="") { $where[] = "object_subtype='$subtype'"; } if ($timebefore) { $where[] = "time_created < " . ((int) $timebefore); } if ($timeafter) { $where[] = "time_created > " . ((int) $timeafter); } if ($object_id) { $where[] = "object_id = " . ((int) $object_id); } $select = "*"; if ($count) { $select = "count(*) as count"; } $query = "SELECT $select from {$CONFIG->dbprefix}system_log where 1 "; foreach ($where as $w) { $query .= " and $w"; } if (!$count) { $query .= " order by time_created desc"; $query .= " limit $offset, $limit"; // Add order and limit } if ($count) { if ($numrows = get_data_row($query)) { return $numrows->count; } } else { return get_data($query); } return false; } /** * Return a specific log entry. * * @param int $entry_id The log entry */ function get_log_entry($entry_id) { global $CONFIG; $entry_id = (int)$entry_id; return get_data_row("SELECT * from {$CONFIG->dbprefix}system_log where id=$entry_id"); } /** * Return the object referred to by a given log entry * * @param int $entry_id The log entry */ function get_object_from_log_entry($entry_id) { $entry = get_log_entry($entry_id); if ($entry) { $class = $entry->object_class; $tmp = new $class(); $object = $tmp->getObjectFromID($entry->object_id); if ($object) { return $object; } } return false; } /** * Log a system event related to a specific object. * * This is called by the event system and should not be called directly. * * @param $object The object you're talking about. * @param $event String The event being logged */ function system_log($object, $event) { global $CONFIG; static $logcache; if ($object instanceof Loggable) { if (!is_array($logcache)) { $logcache = array(); } // Has loggable interface, extract the necessary information and store $object_id = (int)$object->getSystemLogID(); $object_class = $object->getClassName(); $object_type = $object->getType(); $object_subtype = $object->getSubtype(); $event = sanitise_string($event); $time = time(); $performed_by = (int)$_SESSION['guid']; if (isset($object->access_id)) { $access_id = $object->access_id; } else { $access_id = ACCESS_PUBLIC; } if (isset($object->enabled)) { $enabled = $object->enabled; } else { $enabled = 'yes'; } if (isset($object->owner_guid)) { $owner_guid = $object->owner_guid; } else { $owner_guid = 0; } // Create log if we haven't already created it if (!isset($logcache[$time][$object_id][$event])) { insert_data("INSERT DELAYED into {$CONFIG->dbprefix}system_log (object_id, object_class, object_type, object_subtype, event, performed_by_guid, owner_guid, access_id, enabled, time_created) VALUES ('$object_id','$object_class','$object_type', '$object_subtype', '$event',$performed_by, $owner_guid, $access_id, '$enabled', '$time')"); $logcache[$time][$object_id][$event] = true; } return true; } } /** * This function creates an archive copy of the system log. * * @param int $offset An offset in seconds from now to archive (useful for log rotation) */ function archive_log($offset = 0) { global $CONFIG; $offset = (int)$offset; $now = time(); // Take a snapshot of now $ts = $now - $offset; // create table if (!update_data("CREATE TABLE {$CONFIG->dbprefix}system_log_$now as SELECT * from {$CONFIG->dbprefix}system_log WHERE time_created<$ts")) { return false; } // delete // Don't delete on time since we are running in a concurrent environment if (delete_data("DELETE from {$CONFIG->dbprefix}system_log WHERE time_created<$ts") === false) { return false; } // alter table to engine if (!update_data("ALTER TABLE {$CONFIG->dbprefix}system_log_$now engine=archive")) { return false; } return true; } /** * Default system log handler, allows plugins to override, extend or disable logging. * * @param string $event * @param string $object_type * @param Loggable $object * @return unknown */ function system_log_default_logger($event, $object_type, $object) { system_log($object['object'], $object['event']); return true; } /** * System log listener. * This function listens to all events in the system and logs anything appropriate. * * @param String $event * @param String $object_type * @param Loggable $object */ function system_log_listener($event, $object_type, $object) { if (($object_type!='systemlog') && ($event!='log')) { trigger_elgg_event('log', 'systemlog', array('object' => $object, 'event' => $event)); } return true; } /** Register event to listen to all events **/ register_elgg_event_handler('all','all','system_log_listener', 400); /** Register a default system log handler */ register_elgg_event_handler('log','systemlog','system_log_default_logger', 999);