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Differences Between: [Versions 401 and 402] [Versions 401 and 403]

   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  namespace core\lock;
  18  
  19  use core\progress\base;
  20  
  21  /**
  22   * Lock utilities.
  23   *
  24   * @package   core
  25   * @copyright 2023 onwards Catalyst IT EU {@link https://catalyst-eu.net}
  26   * @author    Mark Johnson <mark.johnson@catalyst-eu.net>
  27   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  28   */
  29  class lock_utils {
  30      /**
  31       * Start a progress bar and attempt to get a lock, updating the bar until a lock is achieved.
  32       *
  33       * This will make multiple attempts at getting the lock using a short timeout set by $progressupdatetime. After
  34       * each failed attempt, it will update the progress bar and try again, until $timeout is reached.
  35       *
  36       * @param lock_factory $lockfactory The factory to use to get the lock
  37       * @param string $resource The resource key we will try to get a lock on
  38       * @param base $progress The progress bar
  39       * @param int $timeout The maximum time in seconds to wait for a lock
  40       * @param string $message Optional message to display on the progress bar
  41       * @param int $progressupdatetime The number of seconds to wait for each lock attempt before updating the progress bar.
  42       * @param int $maxlifetime The maxlifetime to set on the lock, if supported.
  43       * @return lock|false A lock if successful, or false if the timeout expires.
  44       * @throws \coding_exception
  45       */
  46      public static function wait_for_lock_with_progress(
  47          lock_factory $lockfactory,
  48          string $resource,
  49          \core\progress\base $progress,
  50          int $timeout,
  51          string $message = '',
  52          int $progressupdatetime = 10,
  53          int $maxlifetime = DAYSECS
  54      ) {
  55          if ($progressupdatetime < 1) {
  56              throw new \invalid_parameter_exception('Progress bar cannot update more than once per second. ' .
  57                  '$progressupdate time must be at least 1.');
  58          }
  59          if ($progressupdatetime > $timeout) {
  60              throw new \invalid_parameter_exception('$timeout must be greater than $progressupdatetime.');
  61          }
  62          $lockattempts = 0;
  63          $maxattempts = $timeout / $progressupdatetime;
  64          $lock = false;
  65          $progress->start_progress($message);
  66          while (!$lock && $lockattempts < $maxattempts) {
  67              $lock = $lockfactory->get_lock($resource, $progressupdatetime, $maxlifetime);
  68              if (!$lock) {
  69                  $progress->progress();
  70                  $lockattempts++;
  71              }
  72          }
  73          $progress->end_progress();
  74          return $lock;
  75      }
  76  }