lib/cronlib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Cron functions.
  19  *
  20  * @package    core
  21  * @subpackage admin
  22  * @copyright  1999 onwards Martin Dougiamas  http://dougiamas.com
  23  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 /**
  27  * Execute cron tasks
  28  */
  29 function cron_run() {
  30     global $DB, $CFG, $OUTPUT;
  31
  32     if (CLI_MAINTENANCE) {
  33         echo "CLI maintenance mode active, cron execution suspended.\n";
  34         exit(1);
  35     }
  36
  37     if (moodle_needs_upgrading()) {
  38         echo "Moodle upgrade pending, cron execution suspended.\n";
  39         exit(1);
  40     }
  41
  42     require_once($CFG->libdir.'/adminlib.php');
  43     require_once($CFG->libdir.'/gradelib.php');
  44
  45     if (!empty($CFG->showcronsql)) {
  46         $DB->set_debug(true);
  47     }
  48     if (!empty($CFG->showcrondebugging)) {
  49         $CFG->debug = DEBUG_DEVELOPER;
  50         $CFG->debugdisplay = true;
  51     }
  52
  53     set_time_limit(0);
  54     $starttime = microtime();
  55
  56     // Increase memory limit
  57     raise_memory_limit(MEMORY_EXTRA);
  58
  59     // Emulate normal session - we use admin accoutn by default
  60     cron_setup_user();
  61
  62     // Start output log
  63     $timenow  = time();
  64     mtrace("Server Time: ".date('r', $timenow)."\n\n");
  65
  66
  67     // Run cleanup core cron jobs, but not every time since they aren't too important.
  68     // These don't have a timer to reduce load, so we'll use a random number
  69     // to randomly choose the percentage of times we should run these jobs.
  70     srand ((double) microtime() * 10000000);
  71     $random100 = rand(0,100);
  72     if ($random100 < 20) {     // Approximately 20% of the time.
  73         mtrace("Running clean-up tasks...");
  74         cron_trace_time_and_memory();
  75
  76         // Delete users who haven't confirmed within required period
  77         if (!empty($CFG->deleteunconfirmed)) {
  78             $cuttime = $timenow - ($CFG->deleteunconfirmed * 3600);
  79             $rs = $DB->get_recordset_sql ("SELECT *
  80                                              FROM {user}
  81                                             WHERE confirmed = 0 AND firstaccess > 0
  82                                                   AND firstaccess < ?", array($cuttime));
  83             foreach ($rs as $user) {
  84                 delete_user($user); // we MUST delete user properly first
  85                 $DB->delete_records('user', array('id'=>$user->id)); // this is a bloody hack, but it might work
  86                 mtrace(" Deleted unconfirmed user for ".fullname($user, true)." ($user->id)");
  87             }
  88             $rs->close();
  89         }
  90
  91
  92         // Delete users who haven't completed profile within required period
  93         if (!empty($CFG->deleteincompleteusers)) {
  94             $cuttime = $timenow - ($CFG->deleteincompleteusers * 3600);
  95             $rs = $DB->get_recordset_sql ("SELECT *
  96                                              FROM {user}
  97                                             WHERE confirmed = 1 AND lastaccess > 0
  98                                                   AND lastaccess < ? AND deleted = 0
  99                                                   AND (lastname = '' OR firstname = '' OR email = '')",
 100                                           array($cuttime));
 101             foreach ($rs as $user) {
 102                 delete_user($user);
 103                 mtrace(" Deleted not fully setup user $user->username ($user->id)");
 104             }
 105             $rs->close();
 106         }
 107
 108
 109         // Delete old logs to save space (this might need a timer to slow it down...)
 110         if (!empty($CFG->loglifetime)) {  // value in days
 111             $loglifetime = $timenow - ($CFG->loglifetime * 3600 * 24);
 112             $DB->delete_records_select("log", "time < ?", array($loglifetime));
 113             mtrace(" Deleted old log records");
 114         }
 115
 116
 117         // Delete old backup_controllers and logs.
 118         $loglifetime = get_config('backup', 'loglifetime');
 119         if (!empty($loglifetime)) {  // Value in days.
 120             $loglifetime = $timenow - ($loglifetime * 3600 * 24);
 121             // Delete child records from backup_logs.
 122             $DB->execute("DELETE FROM {backup_logs}
 123                            WHERE EXISTS (
 124                                SELECT 'x'
 125                                  FROM {backup_controllers} bc
 126                                 WHERE bc.backupid = {backup_logs}.backupid
 127                                   AND bc.timecreated < ?)", array($loglifetime));
 128             // Delete records from backup_controllers.
 129             $DB->execute("DELETE FROM {backup_controllers}
 130                           WHERE timecreated < ?", array($loglifetime));
 131             mtrace(" Deleted old backup records");
 132         }
 133
 134
 135         // Delete old cached texts
 136         if (!empty($CFG->cachetext)) {   // Defined in config.php
 137             $cachelifetime = time() - $CFG->cachetext - 60;  // Add an extra minute to allow for really heavy sites
 138             $DB->delete_records_select('cache_text', "timemodified < ?", array($cachelifetime));
 139             mtrace(" Deleted old cache_text records");
 140         }
 141
 142
 143         if (!empty($CFG->usetags)) {
 144             require_once($CFG->dirroot.'/tag/lib.php');
 145             tag_cron();
 146             mtrace(' Executed tag cron');
 147         }
 148
 149
 150         // Context maintenance stuff
 151         context_helper::cleanup_instances();
 152         mtrace(' Cleaned up context instances');
 153         context_helper::build_all_paths(false);
 154         // If you suspect that the context paths are somehow corrupt
 155         // replace the line below with: context_helper::build_all_paths(true);
 156         mtrace(' Built context paths');
 157
 158
 159         // Remove expired cache flags
 160         gc_cache_flags();
 161         mtrace(' Cleaned cache flags');
 162
 163
 164         // Cleanup messaging
 165         if (!empty($CFG->messagingdeletereadnotificationsdelay)) {
 166             $notificationdeletetime = time() - $CFG->messagingdeletereadnotificationsdelay;
 167             $DB->delete_records_select('message_read', 'notification=1 AND timeread<:notificationdeletetime', array('notificationdeletetime'=>$notificationdeletetime));
 168             mtrace(' Cleaned up read notifications');
 169         }
 170
 171         mtrace("...finished clean-up tasks");
 172
 173     } // End of occasional clean-up tasks
 174
 175
 176     // Send login failures notification - brute force protection in moodle is weak,
 177     // we should at least send notices early in each cron execution
 178     if (notify_login_failures()) {
 179         mtrace(' Notified login failures');
 180     }
 181
 182
 183     // Make sure all context instances are properly created - they may be required in auth, enrol, etc.
 184     context_helper::create_instances();
 185     mtrace(' Created missing context instances');
 186
 187
 188     // Session gc
 189     session_gc();
 190     mtrace("Cleaned up stale user sessions");
 191
 192
 193     // Run the auth cron, if any before enrolments
 194     // because it might add users that will be needed in enrol plugins
 195     $auths = get_enabled_auth_plugins();
 196     mtrace("Running auth crons if required...");
 197     cron_trace_time_and_memory();
 198     foreach ($auths as $auth) {
 199         $authplugin = get_auth_plugin($auth);
 200         if (method_exists($authplugin, 'cron')) {
 201             mtrace("Running cron for auth/$auth...");
 202             $authplugin->cron();
 203             if (!empty($authplugin->log)) {
 204                 mtrace($authplugin->log);
 205             }
 206         }
 207         unset($authplugin);
 208     }
 209     // Generate new password emails for users - ppl expect these generated asap
 210     if ($DB->count_records('user_preferences', array('name'=>'create_password', 'value'=>'1'))) {
 211         mtrace('Creating passwords for new users...');
 212         $newusers = $DB->get_recordset_sql("SELECT u.id as id, u.email, u.firstname,
 213                                                  u.lastname, u.username, u.lang,
 214                                                  p.id as prefid
 215                                             FROM {user} u
 216                                             JOIN {user_preferences} p ON u.id=p.userid
 217                                            WHERE p.name='create_password' AND p.value='1' AND u.email !='' AND u.suspended = 0 AND u.auth != 'nologin' AND u.deleted = 0");
 218
 219         // note: we can not send emails to suspended accounts
 220         foreach ($newusers as $newuser) {
 221             // Use a low cost factor when generating bcrypt hash otherwise
 222             // hashing would be slow when emailing lots of users. Hashes
 223             // will be automatically updated to a higher cost factor the first
 224             // time the user logs in.
 225             if (setnew_password_and_mail($newuser, true)) {
 226                 unset_user_preference('create_password', $newuser);
 227                 set_user_preference('auth_forcepasswordchange', 1, $newuser);
 228             } else {
 229                 trigger_error("Could not create and mail new user password!");
 230             }
 231         }
 232         $newusers->close();
 233     }
 234
 235
 236     // It is very important to run enrol early
 237     // because other plugins depend on correct enrolment info.
 238     mtrace("Running enrol crons if required...");
 239     $enrols = enrol_get_plugins(true);
 240     foreach($enrols as $ename=>$enrol) {
 241         // do this for all plugins, disabled plugins might want to cleanup stuff such as roles
 242         if (!$enrol->is_cron_required()) {
 243             continue;
 244         }
 245         mtrace("Running cron for enrol_$ename...");
 246         cron_trace_time_and_memory();
 247         $enrol->cron();
 248         $enrol->set_config('lastcron', time());
 249     }
 250
 251
 252     // Run all cron jobs for each module
 253     mtrace("Starting activity modules");
 254     get_mailer('buffer');
 255     if ($mods = $DB->get_records_select("modules", "cron > 0 AND ((? - lastcron) > cron) AND visible = 1", array($timenow))) {
 256         foreach ($mods as $mod) {
 257             $libfile = "$CFG->dirroot/mod/$mod->name/lib.php";
 258             if (file_exists($libfile)) {
 259                 include_once($libfile);
 260                 $cron_function = $mod->name."_cron";
 261                 if (function_exists($cron_function)) {
 262                     mtrace("Processing module function $cron_function ...", '');
 263                     cron_trace_time_and_memory();
 264                     $pre_dbqueries = null;
 265                     $pre_dbqueries = $DB->perf_get_queries();
 266                     $pre_time      = microtime(1);
 267                     if ($cron_function()) {
 268                         $DB->set_field("modules", "lastcron", $timenow, array("id"=>$mod->id));
 269                     }
 270                     if (isset($pre_dbqueries)) {
 271                         mtrace("... used " . ($DB->perf_get_queries() - $pre_dbqueries) . " dbqueries");
 272                         mtrace("... used " . (microtime(1) - $pre_time) . " seconds");
 273                     }
 274                     // Reset possible changes by modules to time_limit. MDL-11597
 275                     @set_time_limit(0);
 276                     mtrace("done.");
 277                 }
 278             }
 279         }
 280     }
 281     get_mailer('close');
 282     mtrace("Finished activity modules");
 283
 284
 285     mtrace("Starting blocks");
 286     if ($blocks = $DB->get_records_select("block", "cron > 0 AND ((? - lastcron) > cron) AND visible = 1", array($timenow))) {
 287         // We will need the base class.
 288         require_once($CFG->dirroot.'/blocks/moodleblock.class.php');
 289         foreach ($blocks as $block) {
 290             $blockfile = $CFG->dirroot.'/blocks/'.$block->name.'/block_'.$block->name.'.php';
 291             if (file_exists($blockfile)) {
 292                 require_once($blockfile);
 293                 $classname = 'block_'.$block->name;
 294                 $blockobj = new $classname;
 295                 if (method_exists($blockobj,'cron')) {
 296                     mtrace("Processing cron function for ".$block->name.'....','');
 297                     cron_trace_time_and_memory();
 298                     if ($blockobj->cron()) {
 299                         $DB->set_field('block', 'lastcron', $timenow, array('id'=>$block->id));
 300                     }
 301                     // Reset possible changes by blocks to time_limit. MDL-11597
 302                     @set_time_limit(0);
 303                     mtrace('done.');
 304                 }
 305             }
 306
 307         }
 308     }
 309     mtrace('Finished blocks');
 310
 311
 312     mtrace('Starting admin reports');
 313     cron_execute_plugin_type('report');
 314     mtrace('Finished admin reports');
 315
 316
 317     mtrace('Starting main gradebook job...');
 318     cron_trace_time_and_memory();
 319     grade_cron();
 320     mtrace('done.');
 321
 322
 323     mtrace('Starting processing the event queue...');
 324     cron_trace_time_and_memory();
 325     events_cron();
 326     mtrace('done.');
 327
 328
 329     if ($CFG->enablecompletion) {
 330         // Completion cron
 331         mtrace('Starting the completion cron...');
 332         cron_trace_time_and_memory();
 333         require_once($CFG->dirroot.'/completion/cron.php');
 334         completion_cron();
 335         mtrace('done');
 336     }
 337
 338
 339     if ($CFG->enableportfolios) {
 340         // Portfolio cron
 341         mtrace('Starting the portfolio cron...');
 342         cron_trace_time_and_memory();
 343         require_once($CFG->libdir . '/portfoliolib.php');
 344         portfolio_cron();
 345         mtrace('done');
 346     }
 347
 348
 349     //now do plagiarism checks
 350     require_once($CFG->libdir.'/plagiarismlib.php');
 351     plagiarism_cron();
 352
 353
 354     mtrace('Starting course reports');
 355     cron_execute_plugin_type('coursereport');
 356     mtrace('Finished course reports');
 357
 358
 359     // run gradebook import/export/report cron
 360     mtrace('Starting gradebook plugins');
 361     cron_execute_plugin_type('gradeimport');
 362     cron_execute_plugin_type('gradeexport');
 363     cron_execute_plugin_type('gradereport');
 364     mtrace('Finished gradebook plugins');
 365
 366     // run calendar cron
 367     require_once "{$CFG->dirroot}/calendar/lib.php";
 368     calendar_cron();
 369
 370     // Run external blog cron if needed
 371     if (!empty($CFG->enableblogs) && $CFG->useexternalblogs) {
 372         require_once($CFG->dirroot . '/blog/lib.php');
 373         mtrace("Fetching external blog entries...", '');
 374         cron_trace_time_and_memory();
 375         $sql = "timefetched < ? OR timefetched = 0";
 376         $externalblogs = $DB->get_records_select('blog_external', $sql, array(time() - $CFG->externalblogcrontime));
 377
 378         foreach ($externalblogs as $eb) {
 379             blog_sync_external_entries($eb);
 380         }
 381         mtrace('done.');
 382     }
 383     // Run blog associations cleanup
 384     if (!empty($CFG->enableblogs) && $CFG->useblogassociations) {
 385         require_once($CFG->dirroot . '/blog/lib.php');
 386         // delete entries whose contextids no longer exists
 387         mtrace("Deleting blog associations linked to non-existent contexts...", '');
 388         cron_trace_time_and_memory();
 389         $DB->delete_records_select('blog_association', 'contextid NOT IN (SELECT id FROM {context})');
 390         mtrace('done.');
 391     }
 392
 393
 394     // Run question bank clean-up.
 395     mtrace("Starting the question bank cron...", '');
 396     cron_trace_time_and_memory();
 397     require_once($CFG->libdir . '/questionlib.php');
 398     question_bank::cron();
 399     mtrace('done.');
 400
 401
 402     //Run registration updated cron
 403     mtrace(get_string('siteupdatesstart', 'hub'));
 404     cron_trace_time_and_memory();
 405     require_once($CFG->dirroot . '/' . $CFG->admin . '/registration/lib.php');
 406     $registrationmanager = new registration_manager();
 407     $registrationmanager->cron();
 408     mtrace(get_string('siteupdatesend', 'hub'));
 409
 410     // If enabled, fetch information about available updates and eventually notify site admins
 411     if (empty($CFG->disableupdatenotifications)) {
 412         require_once($CFG->libdir.'/pluginlib.php');
 413         $updateschecker = available_update_checker::instance();
 414         $updateschecker->cron();
 415     }
 416
 417     //cleanup old session linked tokens
 418     //deletes the session linked tokens that are over a day old.
 419     mtrace("Deleting session linked tokens more than one day old...", '');
 420     cron_trace_time_and_memory();
 421     $DB->delete_records_select('external_tokens', 'lastaccess < :onedayago AND tokentype = :tokentype',
 422                     array('onedayago' => time() - DAYSECS, 'tokentype' => EXTERNAL_TOKEN_EMBEDDED));
 423     mtrace('done.');
 424
 425
 426     // all other plugins
 427     cron_execute_plugin_type('message', 'message plugins');
 428     cron_execute_plugin_type('filter', 'filters');
 429     cron_execute_plugin_type('editor', 'editors');
 430     cron_execute_plugin_type('format', 'course formats');
 431     cron_execute_plugin_type('profilefield', 'profile fields');
 432     cron_execute_plugin_type('webservice', 'webservices');
 433     cron_execute_plugin_type('repository', 'repository plugins');
 434     cron_execute_plugin_type('qbehaviour', 'question behaviours');
 435     cron_execute_plugin_type('qformat', 'question import/export formats');
 436     cron_execute_plugin_type('qtype', 'question types');
 437     cron_execute_plugin_type('plagiarism', 'plagiarism plugins');
 438     cron_execute_plugin_type('theme', 'themes');
 439     cron_execute_plugin_type('tool', 'admin tools');
 440
 441
 442     // and finally run any local cronjobs, if any
 443     if ($locals = get_plugin_list('local')) {
 444         mtrace('Processing customized cron scripts ...', '');
 445         // new cron functions in lib.php first
 446         cron_execute_plugin_type('local');
 447         // legacy cron files are executed directly
 448         foreach ($locals as $local => $localdir) {
 449             if (file_exists("$localdir/cron.php")) {
 450                 include("$localdir/cron.php");
 451             }
 452         }
 453         mtrace('done.');
 454     }
 455
 456     mtrace('Running cache cron routines');
 457     cache_helper::cron();
 458     mtrace('done.');
 459
 460     // Run automated backups if required - these may take a long time to execute
 461     require_once($CFG->dirroot.'/backup/util/includes/backup_includes.php');
 462     require_once($CFG->dirroot.'/backup/util/helper/backup_cron_helper.class.php');
 463     backup_cron_automated_helper::run_automated_backup();
 464
 465
 466     // Run stats as at the end because they are known to take very long time on large sites
 467     if (!empty($CFG->enablestats) and empty($CFG->disablestatsprocessing)) {
 468         require_once($CFG->dirroot.'/lib/statslib.php');
 469         // check we're not before our runtime
 470         $timetocheck = stats_get_base_daily() + $CFG->statsruntimestarthour*60*60 + $CFG->statsruntimestartminute*60;
 471
 472         if (time() > $timetocheck) {
 473             // process configured number of days as max (defaulting to 31)
 474             $maxdays = empty($CFG->statsruntimedays) ? 31 : abs($CFG->statsruntimedays);
 475             if (stats_cron_daily($maxdays)) {
 476                 if (stats_cron_weekly()) {
 477                     if (stats_cron_monthly()) {
 478                         stats_clean_old();
 479                     }
 480                 }
 481             }
 482             @set_time_limit(0);
 483         } else {
 484             mtrace('Next stats run after:'. userdate($timetocheck));
 485         }
 486     }
 487
 488     // Run badges review cron.
 489     mtrace("Starting badges cron...");
 490     require_once($CFG->dirroot . '/badges/cron.php');
 491     badge_cron();
 492     mtrace('done.');
 493
 494     // cleanup file trash - not very important
 495     $fs = get_file_storage();
 496     $fs->cron();
 497
 498     mtrace("Cron script completed correctly");
 499
 500     gc_collect_cycles();
 501     mtrace('Cron completed at ' . date('H:i:s') . '. Memory used ' . display_size(memory_get_usage()) . '.');
 502     $difftime = microtime_diff($starttime, microtime());
 503     mtrace("Execution took ".$difftime." seconds");
 504 }
 505
 506 /**
 507  * Executes cron functions for a specific type of plugin.
 508  *
 509  * @param string $plugintype Plugin type (e.g. 'report')
 510  * @param string $description If specified, will display 'Starting (whatever)'
 511  *   and 'Finished (whatever)' lines, otherwise does not display
 512  */
 513 function cron_execute_plugin_type($plugintype, $description = null) {
 514     global $DB;
 515
 516     // Get list from plugin => function for all plugins
 517     $plugins = get_plugin_list_with_function($plugintype, 'cron');
 518
 519     // Modify list for backward compatibility (different files/names)
 520     $plugins = cron_bc_hack_plugin_functions($plugintype, $plugins);
 521
 522     // Return if no plugins with cron function to process
 523     if (!$plugins) {
 524         return;
 525     }
 526
 527     if ($description) {
 528         mtrace('Starting '.$description);
 529     }
 530
 531     foreach ($plugins as $component=>$cronfunction) {
 532         $dir = get_component_directory($component);
 533
 534         // Get cron period if specified in version.php, otherwise assume every cron
 535         $cronperiod = 0;
 536         if (file_exists("$dir/version.php")) {
 537             $plugin = new stdClass();
 538             include("$dir/version.php");
 539             if (isset($plugin->cron)) {
 540                 $cronperiod = $plugin->cron;
 541             }
 542         }
 543
 544         // Using last cron and cron period, don't run if it already ran recently
 545         $lastcron = get_config($component, 'lastcron');
 546         if ($cronperiod && $lastcron) {
 547             if ($lastcron + $cronperiod > time()) {
 548                 // do not execute cron yet
 549                 continue;
 550             }
 551         }
 552
 553         mtrace('Processing cron function for ' . $component . '...');
 554         cron_trace_time_and_memory();
 555         $pre_dbqueries = $DB->perf_get_queries();
 556         $pre_time = microtime(true);
 557
 558         $cronfunction();
 559
 560         mtrace("done. (" . ($DB->perf_get_queries() - $pre_dbqueries) . " dbqueries, " .
 561                 round(microtime(true) - $pre_time, 2) . " seconds)");
 562
 563         set_config('lastcron', time(), $component);
 564         @set_time_limit(0);
 565     }
 566
 567     if ($description) {
 568         mtrace('Finished ' . $description);
 569     }
 570 }
 571
 572 /**
 573  * Used to add in old-style cron functions within plugins that have not been converted to the
 574  * new standard API. (The standard API is frankenstyle_name_cron() in lib.php; some types used
 575  * cron.php and some used a different name.)
 576  *
 577  * @param string $plugintype Plugin type e.g. 'report'
 578  * @param array $plugins Array from plugin name (e.g. 'report_frog') to function name (e.g.
 579  *   'report_frog_cron') for plugin cron functions that were already found using the new API
 580  * @return array Revised version of $plugins that adds in any extra plugin functions found by
 581  *   looking in the older location
 582  */
 583 function cron_bc_hack_plugin_functions($plugintype, $plugins) {
 584     global $CFG; // mandatory in case it is referenced by include()d PHP script
 585
 586     if ($plugintype === 'report') {
 587         // Admin reports only - not course report because course report was
 588         // never implemented before, so doesn't need BC
 589         foreach (get_plugin_list($plugintype) as $pluginname=>$dir) {
 590             $component = $plugintype . '_' . $pluginname;
 591             if (isset($plugins[$component])) {
 592                 // We already have detected the function using the new API
 593                 continue;
 594             }
 595             if (!file_exists("$dir/cron.php")) {
 596                 // No old style cron file present
 597                 continue;
 598             }
 599             include_once("$dir/cron.php");
 600             $cronfunction = $component . '_cron';
 601             if (function_exists($cronfunction)) {
 602                 $plugins[$component] = $cronfunction;
 603             } else {
 604                 debugging("Invalid legacy cron.php detected in $component, " .
 605                         "please use lib.php instead");
 606             }
 607         }
 608     } else if (strpos($plugintype, 'grade') === 0) {
 609         // Detect old style cron function names
 610         // Plugin gradeexport_frog used to use grade_export_frog_cron() instead of
 611         // new standard API gradeexport_frog_cron(). Also applies to gradeimport, gradereport
 612         foreach(get_plugin_list($plugintype) as $pluginname=>$dir) {
 613             $component = $plugintype.'_'.$pluginname;
 614             if (isset($plugins[$component])) {
 615                 // We already have detected the function using the new API
 616                 continue;
 617             }
 618             if (!file_exists("$dir/lib.php")) {
 619                 continue;
 620             }
 621             include_once("$dir/lib.php");
 622             $cronfunction = str_replace('grade', 'grade_', $plugintype) . '_' .
 623                     $pluginname . '_cron';
 624             if (function_exists($cronfunction)) {
 625                 $plugins[$component] = $cronfunction;
 626             }
 627         }
 628     }
 629
 630     return $plugins;
 631 }
 632
 633 /**
 634  * Output some standard information during cron runs. Specifically current time
 635  * and memory usage. This method also does gc_collect_cycles() (before displaying
 636  * memory usage) to try to help PHP manage memory better.
 637  */
 638 function cron_trace_time_and_memory() {
 639     gc_collect_cycles();
 640     mtrace('... started ' . date('H:i:s') . '. Current memory use ' . display_size(memory_get_usage()) . '.');
 641 }
 642
 643 /**
 644  * Notify admin users or admin user of any failed logins (since last notification).
 645  *
 646  * Note that this function must be only executed from the cron script
 647  * It uses the cache_flags system to store temporary records, deleting them
 648  * by name before finishing
 649  *
 650  * @return bool True if executed, false if not
 651  */
 652 function notify_login_failures() {
 653     global $CFG, $DB, $OUTPUT;
 654
 655     if (empty($CFG->notifyloginfailures)) {
 656         return false;
 657     }
 658
 659     $recip = get_users_from_config($CFG->notifyloginfailures, 'moodle/site:config');
 660
 661     if (empty($CFG->lastnotifyfailure)) {
 662         $CFG->lastnotifyfailure=0;
 663     }
 664
 665     // If it has been less than an hour, or if there are no recipients, don't execute.
 666     if (((time() - HOURSECS) < $CFG->lastnotifyfailure) || !is_array($recip) || count($recip) <= 0) {
 667         return false;
 668     }
 669
 670     // we need to deal with the threshold stuff first.
 671     if (empty($CFG->notifyloginthreshold)) {
 672         $CFG->notifyloginthreshold = 10; // default to something sensible.
 673     }
 674
 675     // Get all the IPs with more than notifyloginthreshold failures since lastnotifyfailure
 676     // and insert them into the cache_flags temp table
 677     $sql = "SELECT ip, COUNT(*)
 678               FROM {log}
 679              WHERE module = 'login' AND action = 'error'
 680                    AND time > ?
 681           GROUP BY ip
 682             HAVING COUNT(*) >= ?";
 683     $params = array($CFG->lastnotifyfailure, $CFG->notifyloginthreshold);
 684     $rs = $DB->get_recordset_sql($sql, $params);
 685     foreach ($rs as $iprec) {
 686         if (!empty($iprec->ip)) {
 687             set_cache_flag('login_failure_by_ip', $iprec->ip, '1', 0);
 688         }
 689     }
 690     $rs->close();
 691
 692     // Get all the INFOs with more than notifyloginthreshold failures since lastnotifyfailure
 693     // and insert them into the cache_flags temp table
 694     $sql = "SELECT info, count(*)
 695               FROM {log}
 696              WHERE module = 'login' AND action = 'error'
 697                    AND time > ?
 698           GROUP BY info
 699             HAVING count(*) >= ?";
 700     $params = array($CFG->lastnotifyfailure, $CFG->notifyloginthreshold);
 701     $rs = $DB->get_recordset_sql($sql, $params);
 702     foreach ($rs as $inforec) {
 703         if (!empty($inforec->info)) {
 704             set_cache_flag('login_failure_by_info', $inforec->info, '1', 0);
 705         }
 706     }
 707     $rs->close();
 708
 709     // Now, select all the login error logged records belonging to the ips and infos
 710     // since lastnotifyfailure, that we have stored in the cache_flags table
 711     $sql = "SELECT * FROM (
 712         SELECT l.*, u.firstname, u.lastname
 713               FROM {log} l
 714               JOIN {cache_flags} cf ON l.ip = cf.name
 715          LEFT JOIN {user} u         ON l.userid = u.id
 716              WHERE l.module = 'login' AND l.action = 'error'
 717                    AND l.time > ?
 718                    AND cf.flagtype = 'login_failure_by_ip'
 719         UNION ALL
 720             SELECT l.*, u.firstname, u.lastname
 721               FROM {log} l
 722               JOIN {cache_flags} cf ON l.info = cf.name
 723          LEFT JOIN {user} u         ON l.userid = u.id
 724              WHERE l.module = 'login' AND l.action = 'error'
 725                    AND l.time > ?
 726                    AND cf.flagtype = 'login_failure_by_info') t
 727         ORDER BY t.time DESC";
 728     $params = array($CFG->lastnotifyfailure, $CFG->lastnotifyfailure);
 729
 730     // Init some variables
 731     $count = 0;
 732     $messages = '';
 733     // Iterate over the logs recordset
 734     $rs = $DB->get_recordset_sql($sql, $params);
 735     foreach ($rs as $log) {
 736         $log->time = userdate($log->time);
 737         $messages .= get_string('notifyloginfailuresmessage','',$log)."\n";
 738         $count++;
 739     }
 740     $rs->close();
 741
 742     // If we have something useful to report.
 743     if ($count > 0) {
 744         $site = get_site();
 745         $subject = get_string('notifyloginfailuressubject', '', format_string($site->fullname));
 746         // Calculate the complete body of notification (start + messages + end)
 747         $body = get_string('notifyloginfailuresmessagestart', '', $CFG->wwwroot) .
 748                 (($CFG->lastnotifyfailure != 0) ? '('.userdate($CFG->lastnotifyfailure).')' : '')."\n\n" .
 749                 $messages .
 750                 "\n\n".get_string('notifyloginfailuresmessageend','',$CFG->wwwroot)."\n\n";
 751
 752         // For each destination, send mail
 753         mtrace('Emailing admins about '. $count .' failed login attempts');
 754         foreach ($recip as $admin) {
 755             //emailing the admins directly rather than putting these through the messaging system
 756             email_to_user($admin, generate_email_supportuser(), $subject, $body);
 757         }
 758     }
 759
 760     // Update lastnotifyfailure with current time
 761     set_config('lastnotifyfailure', time());
 762
 763     // Finally, delete all the temp records we have created in cache_flags
 764     $DB->delete_records_select('cache_flags', "flagtype IN ('login_failure_by_ip', 'login_failure_by_info')");
 765
 766     return true;
 767 }