src/Core/Worker.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2022, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Core;
  23
  24 use Friendica\Core\Worker\Entity\Process;
  25 use Friendica\Database\DBA;
  26 use Friendica\DI;
  27 use Friendica\Util\DateTimeFormat;
  28
  29 /**
  30  * Contains the class for the worker background job processing
  31  */
  32 class Worker
  33 {
  34         const STATE_STARTUP    = 1; // Worker is in startup. This takes most time.
  35         const STATE_LONG_LOOP  = 2; // Worker is processing the whole - long - loop.
  36         const STATE_REFETCH    = 3; // Worker had refetched jobs in the execution loop.
  37         const STATE_SHORT_LOOP = 4; // Worker is processing preassigned jobs, thus saving much time.
  38
  39         const FAST_COMMANDS = ['APDelivery', 'Delivery'];
  40
  41         const LOCK_PROCESS = 'worker_process';
  42         const LOCK_WORKER = 'worker';
  43
  44         private static $up_start;
  45         private static $db_duration = 0;
  46         private static $db_duration_count = 0;
  47         private static $db_duration_write = 0;
  48         private static $db_duration_stat = 0;
  49         private static $lock_duration = 0;
  50         private static $last_update;
  51         private static $state;
  52         /** @var Process */
  53         private static $process;
  54
  55         /**
  56          * Processes the tasks that are in the workerqueue table
  57          *
  58          * @param boolean $run_cron Should the cron processes be executed?
  59          * @param Process $process  The current running process
  60          * @return void
  61          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  62          */
  63         public static function processQueue(bool $run_cron, Process $process)
  64         {
  65                 self::$up_start = microtime(true);
  66
  67                 // At first check the maximum load. We shouldn't continue with a high load
  68                 if (DI::system()->isMaxLoadReached()) {
  69                         Logger::notice('Pre check: maximum load reached, quitting.');
  70                         return;
  71                 }
  72
  73                 // We now start the process. This is done after the load check since this could increase the load.
  74                 self::$process = $process;
  75
  76                 // Kill stale processes every 5 minutes
  77                 $last_cleanup = DI::config()->get('system', 'worker_last_cleaned', 0);
  78                 if (time() > ($last_cleanup + 300)) {
  79                         DI::config()->set('system', 'worker_last_cleaned', time());
  80                         Worker\Cron::killStaleWorkers();
  81                 }
  82
  83                 // Check if the system is ready
  84                 if (!self::isReady()) {
  85                         return;
  86                 }
  87
  88                 // Now we start additional cron processes if we should do so
  89                 if ($run_cron) {
  90                         Worker\Cron::run();
  91                 }
  92
  93                 $last_check = $starttime = time();
  94                 self::$state = self::STATE_STARTUP;
  95
  96                 // We fetch the next queue entry that is about to be executed
  97                 while ($r = self::workerProcess()) {
  98                         if (Worker\IPC::JobsExists(getmypid())) {
  99                                 Worker\IPC::DeleteJobState(getmypid());
 100                         }
 101
 102                         // Don't refetch when a worker fetches tasks for multiple workers
 103                         $refetched = DI::config()->get('system', 'worker_multiple_fetch');
 104                         foreach ($r as $entry) {
 105                                 // The work will be done
 106                                 if (!self::execute($entry)) {
 107                                         Logger::warning('Process execution failed, quitting.', ['entry' => $entry]);
 108                                         return;
 109                                 }
 110
 111                                 // Trying to fetch new processes - but only once when successful
 112                                 if (!$refetched && DI::lock()->acquire(self::LOCK_PROCESS, 0)) {
 113                                         self::findWorkerProcesses();
 114                                         DI::lock()->release(self::LOCK_PROCESS);
 115                                         self::$state = self::STATE_REFETCH;
 116                                         $refetched = true;
 117                                 } else {
 118                                         self::$state = self::STATE_SHORT_LOOP;
 119                                 }
 120                         }
 121
 122                         // To avoid the quitting of multiple workers only one worker at a time will execute the check
 123                         if ((time() > $last_check + 5) && !self::getWaitingJobForPID()) {
 124                                 self::$state = self::STATE_LONG_LOOP;
 125
 126                                 if (DI::lock()->acquire(self::LOCK_WORKER, 0)) {
 127                                 // Count active workers and compare them with a maximum value that depends on the load
 128                                         if (self::tooMuchWorkers()) {
 129                                                 Logger::notice('Active worker limit reached, quitting.');
 130                                                 DI::lock()->release(self::LOCK_WORKER);
 131                                                 return;
 132                                         }
 133
 134                                         // Check free memory
 135                                         if (DI::system()->isMinMemoryReached()) {
 136                                                 Logger::warning('Memory limit reached, quitting.');
 137                                                 DI::lock()->release(self::LOCK_WORKER);
 138                                                 return;
 139                                         }
 140                                         DI::lock()->release(self::LOCK_WORKER);
 141                                 }
 142                                 $last_check = time();
 143                         }
 144
 145                         // Quit the worker once every cron interval
 146                         if (time() > ($starttime + (DI::config()->get('system', 'cron_interval') * 60)) && !self::systemLimitReached()) {
 147                                 Logger::info('Process lifetime reached, respawning.');
 148                                 self::unclaimProcess($process);
 149                                 if (Worker\Daemon::isMode()) {
 150                                         Worker\IPC::SetJobState(true);
 151                                 } else {
 152                                         self::spawnWorker();
 153                                 }
 154                                 return;
 155                         }
 156                 }
 157
 158                 // Cleaning up. Possibly not needed, but it doesn't harm anything.
 159                 if (Worker\Daemon::isMode()) {
 160                         Worker\IPC::SetJobState(false);
 161                 }
 162                 Logger::info("Couldn't select a workerqueue entry, quitting process", ['pid' => getmypid()]);
 163         }
 164
 165         /**
 166          * Checks if the system is ready.
 167          *
 168          * Several system parameters like memory, connections and processes are checked.
 169          *
 170          * @return boolean
 171          */
 172         public static function isReady(): bool
 173         {
 174                 // Count active workers and compare them with a maximum value that depends on the load
 175                 if (self::tooMuchWorkers()) {
 176                         Logger::notice('Active worker limit reached, quitting.');
 177                         return false;
 178                 }
 179
 180                 // Do we have too few memory?
 181                 if (DI::system()->isMinMemoryReached()) {
 182                         Logger::warning('Memory limit reached, quitting.');
 183                         return false;
 184                 }
 185
 186                 // Possibly there are too much database connections
 187                 if (self::maxConnectionsReached()) {
 188                         Logger::warning('Maximum connections reached, quitting.');
 189                         return false;
 190                 }
 191
 192                 // Possibly there are too much database processes that block the system
 193                 if (DI::system()->isMaxProcessesReached()) {
 194                         Logger::warning('Maximum processes reached, quitting.');
 195                         return false;
 196                 }
 197
 198                 return true;
 199         }
 200
 201         /**
 202          * Check if non executed tasks do exist in the worker queue
 203          *
 204          * @return boolean Returns "true" if tasks are existing
 205          * @throws \Exception
 206          */
 207         public static function entriesExists(): bool
 208         {
 209                 $stamp = (float)microtime(true);
 210                 $exists = DBA::exists('workerqueue', ["NOT `done` AND `pid` = 0 AND `next_try` < ?", DateTimeFormat::utcNow()]);
 211                 self::$db_duration += (microtime(true) - $stamp);
 212                 return $exists;
 213         }
 214
 215         /**
 216          * Returns the number of deferred entries in the worker queue
 217          *
 218          * @return integer Number of deferred entries in the worker queue
 219          * @throws \Exception
 220          */
 221         private static function deferredEntries(): int
 222         {
 223                 $stamp = (float)microtime(true);
 224                 $count = DBA::count('workerqueue', ["NOT `done` AND `pid` = 0 AND `retrial` > ?", 0]);
 225                 self::$db_duration += (microtime(true) - $stamp);
 226                 self::$db_duration_count += (microtime(true) - $stamp);
 227                 return $count;
 228         }
 229
 230         /**
 231          * Returns the number of non executed entries in the worker queue
 232          *
 233          * @return integer Number of non executed entries in the worker queue
 234          * @throws \Exception
 235          */
 236         private static function totalEntries(): int
 237         {
 238                 $stamp = (float)microtime(true);
 239                 $count = DBA::count('workerqueue', ['done' => false, 'pid' => 0]);
 240                 self::$db_duration += (microtime(true) - $stamp);
 241                 self::$db_duration_count += (microtime(true) - $stamp);
 242                 return $count;
 243         }
 244
 245         /**
 246          * Returns the highest priority in the worker queue that isn't executed
 247          *
 248          * @return integer Number of active worker processes
 249          * @throws \Exception
 250          */
 251         private static function highestPriority(): int
 252         {
 253                 $stamp = (float)microtime(true);
 254                 $condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
 255                 $workerqueue = DBA::selectFirst('workerqueue', ['priority'], $condition, ['order' => ['priority']]);
 256                 self::$db_duration += (microtime(true) - $stamp);
 257                 if (DBA::isResult($workerqueue)) {
 258                         return $workerqueue['priority'];
 259                 } else {
 260                         return 0;
 261                 }
 262         }
 263
 264         /**
 265          * Returns if a process with the given priority is running
 266          *
 267          * @param integer $priority The priority that should be checked
 268          *
 269          * @return integer Is there a process running with that priority?
 270          * @throws \Exception
 271          */
 272         private static function processWithPriorityActive(int $priority): int
 273         {
 274                 $condition = ["`priority` <= ? AND `pid` != 0 AND NOT `done`", $priority];
 275                 return DBA::exists('workerqueue', $condition);
 276         }
 277
 278         /**
 279          * Checks if the given file is valid to be included
 280          *
 281          * @param mixed $file
 282          * @return bool
 283          */
 284         private static function validateInclude(&$file): bool
 285         {
 286                 $orig_file = $file;
 287
 288                 $file = realpath($file);
 289
 290                 if (strpos($file, getcwd()) !== 0) {
 291                         return false;
 292                 }
 293
 294                 $file = str_replace(getcwd() . '/', '', $file, $count);
 295                 if ($count != 1) {
 296                         return false;
 297                 }
 298
 299                 if ($orig_file !== $file) {
 300                         return false;
 301                 }
 302
 303                 $valid = false;
 304                 if (strpos($file, 'include/') === 0) {
 305                         $valid = true;
 306                 }
 307
 308                 if (strpos($file, 'addon/') === 0) {
 309                         $valid = true;
 310                 }
 311
 312                 // Simply return flag
 313                 return $valid;
 314         }
 315
 316         /**
 317          * Execute a worker entry
 318          *
 319          * @param array $queue Workerqueue entry
 320          *
 321          * @return boolean "true" if further processing should be stopped
 322          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 323          */
 324         public static function execute(array $queue): bool
 325         {
 326                 $mypid = getmypid();
 327
 328                 // Quit when in maintenance
 329                 if (DI::config()->get('system', 'maintenance', false, true)) {
 330                         Logger::notice('Maintenance mode - quit process', ['pid' => $mypid]);
 331                         return false;
 332                 }
 333
 334                 // Constantly check the number of parallel database processes
 335                 if (DI::system()->isMaxProcessesReached()) {
 336                         Logger::warning('Max processes reached for process', ['pid' => $mypid]);
 337                         return false;
 338                 }
 339
 340                 // Constantly check the number of available database connections to let the frontend be accessible at any time
 341                 if (self::maxConnectionsReached()) {
 342                         Logger::warning('Max connection reached for process', ['pid' => $mypid]);
 343                         return false;
 344                 }
 345
 346                 $argv = json_decode($queue['parameter'], true);
 347                 if (!is_array($argv)) {
 348                         $argv = [];
 349                 }
 350
 351                 if (!empty($queue['command'])) {
 352                         array_unshift($argv, $queue['command']);
 353                 }
 354
 355                 if (empty($argv)) {
 356                         Logger::warning('Parameter is empty', ['queue' => $queue]);
 357                         return false;
 358                 }
 359
 360                 // Check for existance and validity of the include file
 361                 $include = $argv[0];
 362
 363                 if (method_exists(sprintf('Friendica\Worker\%s', $include), 'execute')) {
 364                         // We constantly update the "executed" date every minute to avoid being killed too soon
 365                         if (!isset(self::$last_update)) {
 366                                 self::$last_update = strtotime($queue['executed']);
 367                         }
 368
 369                         $age = (time() - self::$last_update) / 60;
 370                         self::$last_update = time();
 371
 372                         if ($age > 1) {
 373                                 $stamp = (float)microtime(true);
 374                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 375                                 self::$db_duration += (microtime(true) - $stamp);
 376                                 self::$db_duration_write += (microtime(true) - $stamp);
 377                         }
 378
 379                         array_shift($argv);
 380
 381                         self::execFunction($queue, $include, $argv, true);
 382
 383                         $stamp = (float)microtime(true);
 384                         $condition = ["`id` = ? AND `next_try` < ?", $queue['id'], DateTimeFormat::utcNow()];
 385                         if (DBA::update('workerqueue', ['done' => true], $condition)) {
 386                                 DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 387                         }
 388                         self::$db_duration = (microtime(true) - $stamp);
 389                         self::$db_duration_write += (microtime(true) - $stamp);
 390
 391                         return true;
 392                 }
 393
 394                 // The script could be provided as full path or only with the function name
 395                 if ($include == basename($include)) {
 396                         $include = 'include/' . $include . '.php';
 397                 }
 398
 399                 if (!self::validateInclude($include)) {
 400                         Logger::warning('Include file is not valid', ['file' => $argv[0]]);
 401                         $stamp = (float)microtime(true);
 402                         DBA::delete('workerqueue', ['id' => $queue['id']]);
 403                         self::$db_duration = (microtime(true) - $stamp);
 404                         self::$db_duration_write += (microtime(true) - $stamp);
 405                         return true;
 406                 }
 407
 408                 require_once $include;
 409
 410                 $funcname = str_replace('.php', '', basename($argv[0])) .'_run';
 411
 412                 if (function_exists($funcname)) {
 413                         // We constantly update the "executed" date every minute to avoid being killed too soon
 414                         if (!isset(self::$last_update)) {
 415                                 self::$last_update = strtotime($queue['executed']);
 416                         }
 417
 418                         $age = (time() - self::$last_update) / 60;
 419                         self::$last_update = time();
 420
 421                         if ($age > 1) {
 422                                 $stamp = (float)microtime(true);
 423                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 424                                 self::$db_duration += (microtime(true) - $stamp);
 425                                 self::$db_duration_write += (microtime(true) - $stamp);
 426                         }
 427
 428                         self::execFunction($queue, $funcname, $argv, false);
 429
 430                         $stamp = (float)microtime(true);
 431                         if (DBA::update('workerqueue', ['done' => true], ['id' => $queue['id']])) {
 432                                 DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 433                         }
 434                         self::$db_duration = (microtime(true) - $stamp);
 435                         self::$db_duration_write += (microtime(true) - $stamp);
 436                 } else {
 437                         Logger::warning('Function does not exist', ['function' => $funcname]);
 438                         $stamp = (float)microtime(true);
 439                         DBA::delete('workerqueue', ['id' => $queue['id']]);
 440                         self::$db_duration = (microtime(true) - $stamp);
 441                         self::$db_duration_write += (microtime(true) - $stamp);
 442                 }
 443
 444                 return true;
 445         }
 446
 447         /**
 448          * Checks if system limits are reached.
 449          *
 450          * @return boolean
 451          */
 452         private static function systemLimitReached(): bool
 453         {
 454                 $load_cooldown      = DI::config()->get('system', 'worker_load_cooldown');
 455                 $processes_cooldown = DI::config()->get('system', 'worker_processes_cooldown');
 456
 457                 if (($load_cooldown == 0) && ($processes_cooldown == 0)) {
 458                         return false;
 459                 }
 460
 461                 $load = System::getLoadAvg();
 462                 if (empty($load)) {
 463                         return false;
 464                 }
 465
 466                 if (($load_cooldown > 0) && ($load['average1'] > $load_cooldown)) {
 467                         return true;
 468                 }
 469
 470                 if (($processes_cooldown > 0) && ($load['scheduled'] > $processes_cooldown)) {
 471                         return true;
 472                 }
 473
 474                 return false;
 475         }
 476
 477         /**
 478          * Slow the execution down if the system load is too high
 479          *
 480          * @return void
 481          */
 482         public static function coolDown()
 483         {
 484                 $cooldown = DI::config()->get('system', 'worker_cooldown', 0);
 485                 if ($cooldown > 0) {
 486                         Logger::debug('Wait for cooldown.', ['cooldown' => $cooldown]);
 487                         if ($cooldown < 1) {
 488                                 usleep($cooldown * 1000000);
 489                         } else {
 490                                 sleep($cooldown);
 491                         }
 492                 }
 493
 494                 $load_cooldown      = DI::config()->get('system', 'worker_load_cooldown');
 495                 $processes_cooldown = DI::config()->get('system', 'worker_processes_cooldown');
 496
 497                 if (($load_cooldown == 0) && ($processes_cooldown == 0)) {
 498                         return;
 499                 }
 500
 501                 $sleeping = false;
 502
 503                 while ($load = System::getLoadAvg()) {
 504                         if (($load_cooldown > 0) && ($load['average1'] > $load_cooldown)) {
 505                                 if (!$sleeping) {
 506                                         Logger::notice('Load induced pre execution cooldown.', ['max' => $load_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
 507                                         $sleeping = true;
 508                                 }
 509                                 sleep(1);
 510                                 continue;
 511                         }
 512                         if (($processes_cooldown > 0) && ($load['scheduled'] > $processes_cooldown)) {
 513                                 if (!$sleeping) {
 514                                         Logger::notice('Process induced pre execution cooldown.', ['max' => $processes_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
 515                                         $sleeping = true;
 516                                 }
 517                                 sleep(1);
 518                                 continue;
 519                         }
 520                         break;
 521                 }
 522
 523                 if ($sleeping) {
 524                         Logger::notice('Cooldown ended.', ['max-load' => $load_cooldown, 'max-processes' => $processes_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
 525                 }
 526         }
 527
 528         /**
 529          * Execute a function from the queue
 530          *
 531          * @param array   $queue       Workerqueue entry
 532          * @param string  $funcname    name of the function
 533          * @param array   $argv        Array of values to be passed to the function
 534          * @param boolean $method_call boolean
 535          * @return void
 536          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 537          */
 538         private static function execFunction(array $queue, string $funcname, array $argv, bool $method_call)
 539         {
 540                 $a = DI::app();
 541
 542                 self::coolDown();
 543
 544                 Logger::enableWorker($funcname);
 545
 546                 Logger::info('Process start.', ['priority' => $queue['priority'], 'id' => $queue['id']]);
 547
 548                 $stamp = (float)microtime(true);
 549
 550                 // We use the callstack here to analyze the performance of executed worker entries.
 551                 // For this reason the variables have to be initialized.
 552                 DI::profiler()->reset();
 553
 554                 $a->setQueue($queue);
 555
 556                 $up_duration = microtime(true) - self::$up_start;
 557
 558                 // Reset global data to avoid interferences
 559                 unset($_SESSION);
 560
 561                 // Set the workerLogger as new default logger
 562                 if ($method_call) {
 563                         call_user_func_array(sprintf('Friendica\Worker\%s::execute', $funcname), $argv);
 564                 } else {
 565                         $funcname($argv, count($argv));
 566                 }
 567
 568                 Logger::disableWorker();
 569
 570                 $a->setQueue([]);
 571
 572                 $duration = (microtime(true) - $stamp);
 573
 574                 /* With these values we can analyze how effective the worker is.
 575                  * The database and rest time should be low since this is the unproductive time.
 576                  * The execution time is the productive time.
 577                  * By changing parameters like the maximum number of workers we can check the effectivness.
 578                 */
 579                 $dbtotal = round(self::$db_duration, 2);
 580                 $dbread  = round(self::$db_duration - (self::$db_duration_count + self::$db_duration_write + self::$db_duration_stat), 2);
 581                 $dbcount = round(self::$db_duration_count, 2);
 582                 $dbstat  = round(self::$db_duration_stat, 2);
 583                 $dbwrite = round(self::$db_duration_write, 2);
 584                 $dblock  = round(self::$lock_duration, 2);
 585                 $rest    = round(max(0, $up_duration - (self::$db_duration + self::$lock_duration)), 2);
 586                 $exec    = round($duration, 2);
 587
 588                 Logger::info('Performance:', ['state' => self::$state, 'count' => $dbcount, 'stat' => $dbstat, 'write' => $dbwrite, 'lock' => $dblock, 'total' => $dbtotal, 'rest' => $rest, 'exec' => $exec]);
 589
 590                 self::coolDown();
 591
 592                 self::$up_start = microtime(true);
 593                 self::$db_duration = 0;
 594                 self::$db_duration_count = 0;
 595                 self::$db_duration_stat = 0;
 596                 self::$db_duration_write = 0;
 597                 self::$lock_duration = 0;
 598
 599                 if ($duration > 3600) {
 600                         Logger::info('Longer than 1 hour.', ['priority' => $queue['priority'], 'id' => $queue['id'], 'duration' => round($duration/60, 3)]);
 601                 } elseif ($duration > 600) {
 602                         Logger::info('Longer than 10 minutes.', ['priority' => $queue['priority'], 'id' => $queue['id'], 'duration' => round($duration/60, 3)]);
 603                 } elseif ($duration > 300) {
 604                         Logger::info('Longer than 5 minutes.', ['priority' => $queue['priority'], 'id' => $queue['id'], 'duration' => round($duration/60, 3)]);
 605                 } elseif ($duration > 120) {
 606                         Logger::info('Longer than 2 minutes.', ['priority' => $queue['priority'], 'id' => $queue['id'], 'duration' => round($duration/60, 3)]);
 607                 }
 608
 609                 Logger::info('Process done.', ['priority' => $queue['priority'], 'id' => $queue['id'], 'duration' => round($duration, 3)]);
 610
 611                 DI::profiler()->saveLog(DI::logger(), 'ID ' . $queue['id'] . ': ' . $funcname);
 612         }
 613
 614         /**
 615          * Checks if the number of database connections has reached a critical limit.
 616          *
 617          * @return bool Are more than 3/4 of the maximum connections used?
 618          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 619          */
 620         private static function maxConnectionsReached(): bool
 621         {
 622                 // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 623                 $max = DI::config()->get('system', 'max_connections');
 624
 625                 // Fetch the percentage level where the worker will get active
 626                 $maxlevel = DI::config()->get('system', 'max_connections_level', 75);
 627
 628                 if ($max == 0) {
 629                         // the maximum number of possible user connections can be a system variable
 630                         $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 631                         if (DBA::isResult($r)) {
 632                                 $max = $r['Value'];
 633                         }
 634                         // Or it can be granted. This overrides the system variable
 635                         $stamp = (float)microtime(true);
 636                         $r = DBA::p('SHOW GRANTS');
 637                         self::$db_duration += (microtime(true) - $stamp);
 638                         while ($grants = DBA::fetch($r)) {
 639                                 $grant = array_pop($grants);
 640                                 if (stristr($grant, "GRANT USAGE ON")) {
 641                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 642                                                 $max = $match[1];
 643                                         }
 644                                 }
 645                         }
 646                         DBA::close($r);
 647                 }
 648
 649                 // If $max is set we will use the processlist to determine the current number of connections
 650                 // The processlist only shows entries of the current user
 651                 if ($max != 0) {
 652                         $stamp = (float)microtime(true);
 653                         $r = DBA::p('SHOW PROCESSLIST');
 654                         self::$db_duration += (microtime(true) - $stamp);
 655                         $used = DBA::numRows($r);
 656                         DBA::close($r);
 657
 658                         Logger::info('Connection usage (user values)', ['usage' => $used, 'max' => $max]);
 659
 660                         $level = ($used / $max) * 100;
 661
 662                         if ($level >= $maxlevel) {
 663                                 Logger::warning('Maximum level (' . $maxlevel . '%) of user connections reached: ' . $used .'/' . $max);
 664                                 return true;
 665                         }
 666                 }
 667
 668                 // We will now check for the system values.
 669                 // This limit could be reached although the user limits are fine.
 670                 $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 671                 if (!DBA::isResult($r)) {
 672                         return false;
 673                 }
 674                 $max = intval($r['Value']);
 675                 if ($max == 0) {
 676                         return false;
 677                 }
 678                 $r = DBA::fetchFirst("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 679                 if (!DBA::isResult($r)) {
 680                         return false;
 681                 }
 682                 $used = intval($r['Value']);
 683                 if ($used == 0) {
 684                         return false;
 685                 }
 686                 Logger::info('Connection usage (system values)', ['used' => $used, 'max' => $max]);
 687
 688                 $level = $used / $max * 100;
 689
 690                 if ($level < $maxlevel) {
 691                         return false;
 692                 }
 693                 Logger::warning('Maximum level (' . $level . '%) of system connections reached: ' . $used . '/' . $max);
 694                 return true;
 695         }
 696
 697
 698         /**
 699          * Checks if the number of active workers exceeds the given limits
 700          *
 701          * @return bool Are there too much workers running?
 702          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 703          */
 704         private static function tooMuchWorkers(): bool
 705         {
 706                 $queues = DI::config()->get('system', 'worker_queues', 10);
 707
 708                 $maxqueues = $queues;
 709
 710                 $active = self::activeWorkers();
 711
 712                 // Decrease the number of workers at higher load
 713                 $load = System::currentLoad();
 714                 if ($load) {
 715                         $maxsysload = intval(DI::config()->get('system', 'maxloadavg', 20));
 716
 717                         /* Default exponent 3 causes queues to rapidly decrease as load increases.
 718                          * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
 719                          * For some environments, this rapid decrease is not needed.
 720                          * With exponent 1, you could have 20 max queues at idle and 13 at 37% of $maxsysload.
 721                          */
 722                         $exponent = intval(DI::config()->get('system', 'worker_load_exponent', 3));
 723                         $slope = pow(max(0, $maxsysload - $load) / $maxsysload, $exponent);
 724                         $queues = intval(ceil($slope * $maxqueues));
 725
 726                         $processlist = '';
 727
 728                         if (DI::config()->get('system', 'worker_jpm')) {
 729                                 $intervals = explode(',', DI::config()->get('system', 'worker_jpm_range'));
 730                                 $jobs_per_minute = [];
 731                                 foreach ($intervals as $interval) {
 732                                         if ($interval == 0) {
 733                                                 continue;
 734                                         } else {
 735                                                 $interval = (int)$interval;
 736                                         }
 737
 738                                         $stamp = (float)microtime(true);
 739                                         $jobs = DBA::count('workerqueue', ["`done` AND `executed` > ?", DateTimeFormat::utc('now - ' . $interval . ' minute')]);
 740                                         self::$db_duration += (microtime(true) - $stamp);
 741                                         self::$db_duration_stat += (microtime(true) - $stamp);
 742                                         $jobs_per_minute[$interval] = number_format($jobs / $interval, 0);
 743                                 }
 744                                 $processlist = ' - jpm: '.implode('/', $jobs_per_minute);
 745                         }
 746
 747                         // Create a list of queue entries grouped by their priority
 748                         $listitem = [0 => ''];
 749
 750                         $idle_workers = $active;
 751
 752                         $deferred = self::deferredEntries();
 753
 754                         if (DI::config()->get('system', 'worker_debug')) {
 755                                 $waiting_processes = 0;
 756                                 // Now adding all processes with workerqueue entries
 757                                 $stamp = (float)microtime(true);
 758                                 $jobs = DBA::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 759                                 self::$db_duration += (microtime(true) - $stamp);
 760                                 self::$db_duration_stat += (microtime(true) - $stamp);
 761                                 while ($entry = DBA::fetch($jobs)) {
 762                                         $stamp = (float)microtime(true);
 763                                         $running = DBA::count('workerqueue-view', ['priority' => $entry['priority']]);
 764                                         self::$db_duration += (microtime(true) - $stamp);
 765                                         self::$db_duration_stat += (microtime(true) - $stamp);
 766                                         $idle_workers -= $running;
 767                                         $waiting_processes += $entry['entries'];
 768                                         $listitem[$entry['priority']] = $entry['priority'] . ':' . $running . '/' . $entry['entries'];
 769                                 }
 770                                 DBA::close($jobs);
 771                         } else {
 772                                 $waiting_processes =  self::totalEntries();
 773                                 $stamp = (float)microtime(true);
 774                                 $jobs = DBA::p("SELECT COUNT(*) AS `running`, `priority` FROM `workerqueue-view` GROUP BY `priority` ORDER BY `priority`");
 775                                 self::$db_duration += (microtime(true) - $stamp);
 776                                 self::$db_duration_stat += (microtime(true) - $stamp);
 777
 778                                 while ($entry = DBA::fetch($jobs)) {
 779                                         $idle_workers -= $entry['running'];
 780                                         $listitem[$entry['priority']] = $entry['priority'] . ':' . $entry['running'];
 781                                 }
 782                                 DBA::close($jobs);
 783                         }
 784
 785                         $waiting_processes -= $deferred;
 786
 787                         $listitem[0] = '0:' . max(0, $idle_workers);
 788
 789                         $processlist .= ' ('.implode(', ', $listitem).')';
 790
 791                         if (DI::config()->get('system', 'worker_fastlane', false) && ($queues > 0) && ($active >= $queues) && self::entriesExists()) {
 792                                 $top_priority = self::highestPriority();
 793                                 $high_running = self::processWithPriorityActive($top_priority);
 794
 795                                 if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 796                                         Logger::info('Jobs with a higher priority are waiting but none is executed. Open a fastlane.', ['priority' => $top_priority]);
 797                                         $queues = $active + 1;
 798                                 }
 799                         }
 800
 801                         Logger::notice('Load: ' . $load . '/' . $maxsysload . ' - processes: ' . $deferred . '/' . $active . '/' . $waiting_processes . $processlist . ' - maximum: ' . $queues . '/' . $maxqueues);
 802
 803                         // Are there fewer workers running as possible? Then fork a new one.
 804                         if (!DI::config()->get('system', 'worker_dont_fork', false) && ($queues > ($active + 1)) && self::entriesExists() && !self::systemLimitReached()) {
 805                                 Logger::info('There are fewer workers as possible, fork a new worker.', ['active' => $active, 'queues' => $queues]);
 806                                 if (Worker\Daemon::isMode()) {
 807                                         Worker\IPC::SetJobState(true);
 808                                 } else {
 809                                         self::spawnWorker();
 810                                 }
 811                         }
 812                 }
 813
 814                 // if there are too much worker, we don't spawn a new one.
 815                 if (Worker\Daemon::isMode() && ($active > $queues)) {
 816                         Worker\IPC::SetJobState(false);
 817                 }
 818
 819                 return $active > $queues;
 820         }
 821
 822         /**
 823          * Returns the number of active worker processes
 824          *
 825          * @return integer Number of active worker processes
 826          * @throws \Exception
 827          */
 828         private static function activeWorkers(): int
 829         {
 830                 $stamp = (float)microtime(true);
 831                 $count = DI::process()->countCommand('Worker.php');
 832                 self::$db_duration += (microtime(true) - $stamp);
 833                 self::$db_duration_count += (microtime(true) - $stamp);
 834                 return $count;
 835         }
 836
 837         /**
 838          * Returns the number of active worker processes
 839          *
 840          * @return array List of worker process ids
 841          * @throws \Exception
 842          */
 843         private static function getWorkerPIDList(): array
 844         {
 845                 $ids = [];
 846                 $stamp = (float)microtime(true);
 847
 848                 $queues = DBA::p("SELECT `process`.`pid`, COUNT(`workerqueue`.`pid`) AS `entries` FROM `process`
 849                         LEFT JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `workerqueue`.`done`
 850                         GROUP BY `process`.`pid`");
 851                 while ($queue = DBA::fetch($queues)) {
 852                         $ids[$queue['pid']] = $queue['entries'];
 853                 }
 854                 DBA::close($queues);
 855
 856                 self::$db_duration += (microtime(true) - $stamp);
 857                 self::$db_duration_count += (microtime(true) - $stamp);
 858                 return $ids;
 859         }
 860
 861         /**
 862          * Returns waiting jobs for the current process id
 863          *
 864          * @return array|bool waiting workerqueue jobs or FALSE on failture
 865          * @throws \Exception
 866          */
 867         private static function getWaitingJobForPID()
 868         {
 869                 $stamp = (float)microtime(true);
 870                 $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 871                 self::$db_duration += (microtime(true) - $stamp);
 872                 if (DBA::isResult($r)) {
 873                         return DBA::toArray($r);
 874                 }
 875                 DBA::close($r);
 876
 877                 return false;
 878         }
 879
 880         /**
 881          * Returns the next jobs that should be executed
 882          * @param int $limit
 883          * @return array array with next jobs
 884          * @throws \Exception
 885          */
 886         private static function nextProcess(int $limit): array
 887         {
 888                 $priority = self::nextPriority();
 889                 if (empty($priority)) {
 890                         Logger::info('No tasks found');
 891                         return [];
 892                 }
 893
 894                 $ids = [];
 895                 $stamp = (float)microtime(true);
 896                 $condition = ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()];
 897                 $tasks = DBA::select('workerqueue', ['id', 'command', 'parameter'], $condition, ['limit' => $limit, 'order' => ['retrial', 'created']]);
 898                 self::$db_duration += (microtime(true) - $stamp);
 899                 while ($task = DBA::fetch($tasks)) {
 900                         $ids[] = $task['id'];
 901                         // Only continue that loop while we are storing commands that can be processed quickly
 902                         if (!empty($task['command'])) {
 903                                 $command = $task['command'];
 904                         } else {
 905                                 $command = json_decode($task['parameter'])[0];
 906                         }
 907
 908                         if (!in_array($command, self::FAST_COMMANDS)) {
 909                                 break;
 910                         }
 911                 }
 912                 DBA::close($tasks);
 913
 914                 Logger::info('Found:', ['priority' => $priority, 'id' => $ids]);
 915                 return $ids;
 916         }
 917
 918         /**
 919          * Returns the priority of the next workerqueue job
 920          *
 921          * @return string|bool priority or FALSE on failure
 922          * @throws \Exception
 923          */
 924         private static function nextPriority()
 925         {
 926                 $waiting = [];
 927                 $priorities = [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE];
 928                 foreach ($priorities as $priority) {
 929                         $stamp = (float)microtime(true);
 930                         if (DBA::exists('workerqueue', ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()])) {
 931                                 $waiting[$priority] = true;
 932                         }
 933                         self::$db_duration += (microtime(true) - $stamp);
 934                 }
 935
 936                 if (!empty($waiting[PRIORITY_CRITICAL])) {
 937                         return PRIORITY_CRITICAL;
 938                 }
 939
 940                 $running = [];
 941                 $running_total = 0;
 942                 $stamp = (float)microtime(true);
 943                 $processes = DBA::p("SELECT COUNT(DISTINCT(`pid`)) AS `running`, `priority` FROM `workerqueue-view` GROUP BY `priority`");
 944                 self::$db_duration += (microtime(true) - $stamp);
 945                 while ($process = DBA::fetch($processes)) {
 946                         $running[$process['priority']] = $process['running'];
 947                         $running_total += $process['running'];
 948                 }
 949                 DBA::close($processes);
 950
 951                 foreach ($priorities as $priority) {
 952                         if (!empty($waiting[$priority]) && empty($running[$priority])) {
 953                                 Logger::info('No running worker found with priority {priority} - assigning it.', ['priority' => $priority]);
 954                                 return $priority;
 955                         }
 956                 }
 957
 958                 $active = max(self::activeWorkers(), $running_total);
 959                 $priorities = max(count($waiting), count($running));
 960                 $exponent = 2;
 961
 962                 $total = 0;
 963                 for ($i = 1; $i <= $priorities; ++$i) {
 964                         $total += pow($i, $exponent);
 965                 }
 966
 967                 $limit = [];
 968                 for ($i = 1; $i <= $priorities; ++$i) {
 969                         $limit[$priorities - $i] = max(1, round($active * (pow($i, $exponent) / $total)));
 970                 }
 971
 972                 $i = 0;
 973                 foreach ($running as $priority => $workers) {
 974                         if ($workers < $limit[$i++]) {
 975                                 Logger::info('Priority {priority} has got {workers} workers out of a limit of {limit}', ['priority' => $priority, 'workers' => $workers, 'limit' => $limit[$i - 1]]);
 976                                 return $priority;
 977                         }
 978                 }
 979
 980                 if (!empty($waiting)) {
 981                         $priority = array_keys($waiting)[0];
 982                         Logger::info('No underassigned priority found, now taking the highest priority.', ['priority' => $priority]);
 983                         return $priority;
 984                 }
 985
 986                 return false;
 987         }
 988
 989         /**
 990          * Find and claim the next worker process for us
 991          *
 992          * @return void
 993          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 994          */
 995         private static function findWorkerProcesses()
 996         {
 997                 $fetch_limit = DI::config()->get('system', 'worker_fetch_limit', 1);
 998
 999                 if (DI::config()->get('system', 'worker_multiple_fetch')) {
1000                         $pids = [];
1001                         foreach (self::getWorkerPIDList() as $pid => $count) {
1002                                 if ($count <= $fetch_limit) {
1003                                         $pids[] = $pid;
1004                                 }
1005                         }
1006                         if (empty($pids)) {
1007                                 return;
1008                         }
1009                         $limit = $fetch_limit * count($pids);
1010                 } else {
1011                         $pids = [getmypid()];
1012                         $limit = $fetch_limit;
1013                 }
1014
1015                 $ids = self::nextProcess($limit);
1016                 $limit -= count($ids);
1017
1018                 // If there is not enough results we check without priority limit
1019                 if ($limit > 0) {
1020                         $stamp = (float)microtime(true);
1021                         $condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
1022                         $tasks = DBA::select('workerqueue', ['id', 'command', 'parameter'], $condition, ['limit' => $limit, 'order' => ['priority', 'retrial', 'created']]);
1023                         self::$db_duration += (microtime(true) - $stamp);
1024
1025                         while ($task = DBA::fetch($tasks)) {
1026                                 $ids[] = $task['id'];
1027                                 // Only continue that loop while we are storing commands that can be processed quickly
1028                                 if (!empty($task['command'])) {
1029                                         $command = $task['command'];
1030                                 } else {
1031                                         $command = json_decode($task['parameter'])[0];
1032                                 }
1033                                 if (!in_array($command, self::FAST_COMMANDS)) {
1034                                         break;
1035                                 }
1036                         }
1037                         DBA::close($tasks);
1038                 }
1039
1040                 if (empty($ids)) {
1041                         return;
1042                 }
1043
1044                 // Assign the task ids to the workers
1045                 $worker = [];
1046                 foreach (array_unique($ids) as $id) {
1047                         $pid = next($pids);
1048                         if (!$pid) {
1049                                 $pid = reset($pids);
1050                         }
1051                         $worker[$pid][] = $id;
1052                 }
1053
1054                 $stamp = (float)microtime(true);
1055                 foreach ($worker as $worker_pid => $worker_ids) {
1056                         Logger::info('Set queue entry', ['pid' => $worker_pid, 'ids' => $worker_ids]);
1057                         DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $worker_pid],
1058                                 ['id' => $worker_ids, 'done' => false, 'pid' => 0]);
1059                 }
1060                 self::$db_duration += (microtime(true) - $stamp);
1061                 self::$db_duration_write += (microtime(true) - $stamp);
1062         }
1063
1064         /**
1065          * Returns the next worker process
1066          *
1067          * @return array worker processes
1068          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1069          */
1070         public static function workerProcess(): array
1071         {
1072                 // There can already be jobs for us in the queue.
1073                 $waiting = self::getWaitingJobForPID();
1074                 if (!empty($waiting)) {
1075                         return $waiting;
1076                 }
1077
1078                 $stamp = (float)microtime(true);
1079                 if (!DI::lock()->acquire(self::LOCK_PROCESS)) {
1080                         return [];
1081                 }
1082                 self::$lock_duration += (microtime(true) - $stamp);
1083
1084                 self::findWorkerProcesses();
1085
1086                 DI::lock()->release(self::LOCK_PROCESS);
1087
1088                 // Prevents "Return value of Friendica\Core\Worker::workerProcess() must be of the type array, bool returned"
1089                 $process = self::getWaitingJobForPID();
1090                 return (is_array($process) ? $process : []);
1091         }
1092
1093         /**
1094          * Removes a workerqueue entry from the current process
1095          *
1096          * @param Process $process the process behind the workerqueue
1097          *
1098          * @return void
1099          * @throws \Exception
1100          */
1101         public static function unclaimProcess(Process $process)
1102         {
1103                 $stamp = (float)microtime(true);
1104                 DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $process->pid, 'done' => false]);
1105                 self::$db_duration += (microtime(true) - $stamp);
1106                 self::$db_duration_write += (microtime(true) - $stamp);
1107         }
1108
1109         /**
1110          * Fork a child process
1111          *
1112          * @param boolean $do_cron
1113          * @return void
1114          */
1115         private static function forkProcess(bool $do_cron)
1116         {
1117                 if (DI::system()->isMinMemoryReached()) {
1118                         Logger::warning('Memory limit reached - quitting');
1119                         return;
1120                 }
1121
1122                 // Children inherit their parent's database connection.
1123                 // To avoid problems we disconnect and connect both parent and child
1124                 DBA::disconnect();
1125                 $pid = pcntl_fork();
1126                 if ($pid == -1) {
1127                         DBA::connect();
1128                         Logger::warning('Could not spawn worker');
1129                         return;
1130                 } elseif ($pid) {
1131                         // The parent process continues here
1132                         DBA::connect();
1133
1134                         Worker\IPC::SetJobState(true, $pid);
1135                         Logger::info('Spawned new worker', ['pid' => $pid]);
1136
1137                         $cycles = 0;
1138                         while (Worker\IPC::JobsExists($pid) && (++$cycles < 100)) {
1139                                 usleep(10000);
1140                         }
1141
1142                         Logger::info('Spawned worker is ready', ['pid' => $pid, 'wait_cycles' => $cycles]);
1143                         return;
1144                 }
1145
1146                 // We now are in the new worker
1147                 DBA::connect();
1148
1149                 DI::flushLogger();
1150                 $process = DI::process()->create(getmypid(), basename(__FILE__));
1151
1152                 $cycles = 0;
1153                 while (!Worker\IPC::JobsExists($process->pid) && (++$cycles < 100)) {
1154                         usleep(10000);
1155                 }
1156
1157                 Logger::info('Worker spawned', ['pid' => $process->pid, 'wait_cycles' => $cycles]);
1158
1159                 self::processQueue($do_cron, $process);
1160
1161                 self::unclaimProcess($process);
1162
1163                 Worker\IPC::SetJobState(false, $process->pid);
1164                 DI::process()->delete($process);
1165                 Logger::info('Worker ended', ['pid' => $process->pid]);
1166                 exit();
1167         }
1168
1169         /**
1170          * Spawns a new worker
1171          *
1172          * @param bool $do_cron
1173          * @return void
1174          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1175          */
1176         public static function spawnWorker(bool $do_cron = false)
1177         {
1178                 if (Worker\Daemon::isMode() && DI::config()->get('system', 'worker_fork')) {
1179                         self::forkProcess($do_cron);
1180                 } else {
1181                         DI::system()->run('bin/worker.php', ['no_cron' => !$do_cron]);
1182                 }
1183                 if (Worker\Daemon::isMode()) {
1184                         Worker\IPC::SetJobState(false);
1185                 }
1186         }
1187
1188         /**
1189          * Adds tasks to the worker queue
1190          *
1191          * @param (integer|array) priority or parameter array, strings are deprecated and are ignored
1192          *
1193          * next args are passed as $cmd command line
1194          * or: Worker::add(PRIORITY_HIGH, 'Notifier', Delivery::DELETION, $drop_id);
1195          * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), 'Delivery', $post_id);
1196          *
1197          * @return int '0' if worker queue entry already existed or there had been an error, otherwise the ID of the worker task
1198          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1199          * @note $cmd and string args are surrounded with ''
1200          *
1201          * @hooks 'proc_run'
1202          *    array $arr
1203          *
1204          */
1205         public static function add(...$args)
1206         {
1207                 if (!count($args)) {
1208                         return 0;
1209                 }
1210
1211                 $arr = ['args' => $args, 'run_cmd' => true];
1212
1213                 Hook::callAll('proc_run', $arr);
1214                 if (!$arr['run_cmd'] || !count($args)) {
1215                         return 1;
1216                 }
1217
1218                 $priority = PRIORITY_MEDIUM;
1219                 // Don't fork from frontend tasks by default
1220                 $dont_fork = DI::config()->get('system', 'worker_dont_fork', false) || !DI::mode()->isBackend();
1221                 $created = DateTimeFormat::utcNow();
1222                 $delayed = DBA::NULL_DATETIME;
1223                 $force_priority = false;
1224
1225                 $run_parameter = array_shift($args);
1226
1227                 if (is_int($run_parameter)) {
1228                         $priority = $run_parameter;
1229                 } elseif (is_array($run_parameter)) {
1230                         if (isset($run_parameter['delayed'])) {
1231                                 $delayed = $run_parameter['delayed'];
1232                         }
1233                         if (isset($run_parameter['priority'])) {
1234                                 $priority = $run_parameter['priority'];
1235                         }
1236                         if (isset($run_parameter['created'])) {
1237                                 $created = $run_parameter['created'];
1238                         }
1239                         if (isset($run_parameter['dont_fork'])) {
1240                                 $dont_fork = $run_parameter['dont_fork'];
1241                         }
1242                         if (isset($run_parameter['force_priority'])) {
1243                                 $force_priority = $run_parameter['force_priority'];
1244                         }
1245                 } else {
1246                         throw new \InvalidArgumentException('Priority number or task parameter array expected as first argument');
1247                 }
1248
1249                 $command = array_shift($args);
1250                 $parameters = json_encode($args);
1251                 $found = DBA::exists('workerqueue', ['command' => $command, 'parameter' => $parameters, 'done' => false]);
1252                 $added = 0;
1253
1254                 if (!is_int($priority) || !in_array($priority, PRIORITIES)) {
1255                         Logger::warning('Invalid priority', ['priority' => $priority, 'command' => $command, 'callstack' => System::callstack(20)]);
1256                         $priority = PRIORITY_MEDIUM;
1257                 }
1258
1259                 // Quit if there was a database error - a precaution for the update process to 3.5.3
1260                 if (DBA::errorNo() != 0) {
1261                         return 0;
1262                 }
1263
1264                 if (!$found) {
1265                         if (!DBA::insert('workerqueue', ['command' => $command, 'parameter' => $parameters, 'created' => $created,
1266                                 'priority' => $priority, 'next_try' => $delayed])) {
1267                                 return 0;
1268                         }
1269                         $added = DBA::lastInsertId();
1270                 } elseif ($force_priority) {
1271                         DBA::update('workerqueue', ['priority' => $priority], ['command' => $command, 'parameter' => $parameters, 'done' => false, 'pid' => 0]);
1272                 }
1273
1274                 // Set the IPC flag to ensure an immediate process execution via daemon
1275                 if (Worker\Daemon::isMode()) {
1276                         Worker\IPC::SetJobState(true);
1277                 }
1278
1279                 Worker\Daemon::checkState();
1280
1281                 // Should we quit and wait for the worker to be called as a cronjob?
1282                 if ($dont_fork || self::systemLimitReached()) {
1283                         return $added;
1284                 }
1285
1286                 // If there is a lock then we don't have to check for too much worker
1287                 if (!DI::lock()->acquire(self::LOCK_WORKER, 0)) {
1288                         return $added;
1289                 }
1290
1291                 // If there are already enough workers running, don't fork another one
1292                 $quit = self::tooMuchWorkers();
1293                 DI::lock()->release(self::LOCK_WORKER);
1294
1295                 if ($quit) {
1296                         return $added;
1297                 }
1298
1299                 // Quit on daemon mode
1300                 if (Worker\Daemon::isMode()) {
1301                         return $added;
1302                 }
1303
1304                 // Now call the worker to execute the jobs that we just added to the queue
1305                 self::spawnWorker();
1306
1307                 return $added;
1308         }
1309
1310         public static function countWorkersByCommand(string $command): int
1311         {
1312                 return DBA::count('workerqueue', ['done' => false, 'pid' => 0, 'command' => $command]);
1313         }
1314
1315         /**
1316          * Returns the next retrial level for worker jobs.
1317          * This function will skip levels when jobs are older.
1318          *
1319          * @param array $queue Worker queue entry
1320          * @param integer $max_level maximum retrial level
1321          * @return integer the next retrial level value
1322          */
1323         private static function getNextRetrial(array $queue, int $max_level): int
1324         {
1325                 $created = strtotime($queue['created']);
1326                 $retrial_time = time() - $created;
1327
1328                 $new_retrial = $queue['retrial'] + 1;
1329                 $total = 0;
1330                 for ($retrial = 0; $retrial <= $max_level + 1; ++$retrial) {
1331                         $delay = (($retrial + 3) ** 4) + (rand(1, 30) * ($retrial + 1));
1332                         $total += $delay;
1333                         if (($total < $retrial_time) && ($retrial > $queue['retrial'])) {
1334                                 $new_retrial = $retrial;
1335                         }
1336                 }
1337                 Logger::notice('New retrial for task', ['id' => $queue['id'], 'created' => $queue['created'], 'old' => $queue['retrial'], 'new' => $new_retrial]);
1338                 return $new_retrial;
1339         }
1340
1341         /**
1342          * Defers the current worker entry
1343          *
1344          * @return boolean had the entry been deferred?
1345          * @throws \Exception
1346          */
1347         public static function defer(): bool
1348         {
1349                 $queue = DI::app()->getQueue();
1350
1351                 if (empty($queue)) {
1352                         return false;
1353                 }
1354
1355                 $id = $queue['id'];
1356                 $priority = $queue['priority'];
1357
1358                 $max_level = DI::config()->get('system', 'worker_defer_limit');
1359
1360                 $new_retrial = self::getNextRetrial($queue, $max_level);
1361
1362                 if ($new_retrial > $max_level) {
1363                         Logger::notice('The task exceeded the maximum retry count', ['id' => $id, 'created' => $queue['created'], 'old_prio' => $queue['priority'], 'old_retrial' => $queue['retrial'], 'max_level' => $max_level, 'retrial' => $new_retrial]);
1364                         return false;
1365                 }
1366
1367                 // Calculate the delay until the next trial
1368                 $delay = (($new_retrial + 2) ** 4) + (rand(1, 30) * ($new_retrial));
1369                 $next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
1370
1371                 if (($priority < PRIORITY_MEDIUM) && ($new_retrial > 3)) {
1372                         $priority = PRIORITY_MEDIUM;
1373                 } elseif (($priority < PRIORITY_LOW) && ($new_retrial > 6)) {
1374                         $priority = PRIORITY_LOW;
1375                 } elseif (($priority < PRIORITY_NEGLIGIBLE) && ($new_retrial > 8)) {
1376                         $priority = PRIORITY_NEGLIGIBLE;
1377                 }
1378
1379                 Logger::info('Deferred task', ['id' => $id, 'retrial' => $new_retrial, 'created' => $queue['created'], 'next_execution' => $next, 'old_prio' => $queue['priority'], 'new_prio' => $priority]);
1380
1381                 $stamp = (float)microtime(true);
1382                 $fields = ['retrial' => $new_retrial, 'next_try' => $next, 'executed' => DBA::NULL_DATETIME, 'pid' => 0, 'priority' => $priority];
1383                 DBA::update('workerqueue', $fields, ['id' => $id]);
1384                 self::$db_duration += (microtime(true) - $stamp);
1385                 self::$db_duration_write += (microtime(true) - $stamp);
1386
1387                 return true;
1388         }
1389
1390         /**
1391          * Check if the system is inside the defined maintenance window
1392          *
1393          * @param bool $check_last_execution Whether check last execution
1394          * @return boolean
1395          */
1396         public static function isInMaintenanceWindow(bool $check_last_execution = false): bool
1397         {
1398                 // Calculate the seconds of the start end end of the maintenance window
1399                 $start = strtotime(DI::config()->get('system', 'maintenance_start')) % 86400;
1400                 $end = strtotime(DI::config()->get('system', 'maintenance_end')) % 86400;
1401
1402                 Logger::info('Maintenance window', ['start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1403
1404                 if ($check_last_execution) {
1405                         // Calculate the window duration
1406                         $duration = max($start, $end) - min($start, $end);
1407
1408                         // Quit when the last cron execution had been after the previous window
1409                         $last_cron = DI::config()->get('system', 'last_cron_daily');
1410                         if ($last_cron + $duration > time()) {
1411                                 Logger::info('The Daily cron had been executed recently', ['last' => date(DateTimeFormat::MYSQL, $last_cron), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1412                                 return false;
1413                         }
1414                 }
1415
1416                 $current = time() % 86400;
1417
1418                 if ($start < $end) {
1419                         // Execute if we are inside the window
1420                         $execute = ($current >= $start) && ($current <= $end);
1421                 } else {
1422                         // Don't execute if we are outside the window
1423                         $execute = !(($current > $end) && ($current < $start));
1424                 }
1425
1426                 if ($execute) {
1427                         Logger::info('We are inside the maintenance window', ['current' => date('H:i:s', $current), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1428                 } else {
1429                         Logger::info('We are outside the maintenance window', ['current' => date('H:i:s', $current), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1430                 }
1431
1432                 return $execute;
1433         }
1434 }