Search moodle.org's
Developer Documentation

See Release Notes

  • Bug fixes for general core bugs in 3.10.x will end 8 November 2021 (12 months).
  • Bug fixes for security issues in 3.10.x will end 9 May 2022 (18 months).
  • PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.
   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   * Helper trait buffered_writer
  19   *
  20   * @package    tool_log
  21   * @copyright  2014 onwards Ankit Agarwal
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace tool_log\helper;
  26  defined('MOODLE_INTERNAL') || die();
  27  
  28  /**
  29   * Helper trait buffered_writer. Adds buffer support for the store.
  30   *
  31   * @package    tool_log
  32   * @copyright  2014 onwards Ankit Agarwal
  33   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  34   */
  35  trait buffered_writer {
  36  
  37      /** @var array $buffer buffer of events. */
  38      protected $buffer = array();
  39  
  40      /** @var array $buffer buffer size of events. */
  41      protected $buffersize;
  42  
  43      /** @var int $count Counter. */
  44      protected $count = 0;
  45  
  46      /** @var bool If true, writes JSON instead of PHP serialized data for 'other' field */
  47      protected $jsonformat = false;
  48  
  49      /**
  50       * Should the event be ignored (== not logged)?
  51       * @param \core\event\base $event
  52       * @return bool
  53       */
  54      abstract protected function is_event_ignored(\core\event\base $event);
  55  
  56      /**
  57       * Write event in the store with buffering. Method insert_event_entries() must be
  58       * defined.
  59       *
  60       * @param \core\event\base $event
  61       *
  62       * @return void
  63       */
  64      public function write(\core\event\base $event) {
  65          global $PAGE;
  66  
  67          if ($this->is_event_ignored($event)) {
  68              return;
  69          }
  70  
  71          // We need to capture current info at this moment,
  72          // at the same time this lowers memory use because
  73          // snapshots and custom objects may be garbage collected.
  74          $entry = $event->get_data();
  75          if ($this->jsonformat) {
  76              $entry['other'] = json_encode($entry['other']);
  77          } else {
  78              $entry['other'] = serialize($entry['other']);
  79          }
  80          $entry['origin'] = $PAGE->requestorigin;
  81          $entry['ip'] = $PAGE->requestip;
  82          $entry['realuserid'] = \core\session\manager::is_loggedinas() ? $GLOBALS['USER']->realuser : null;
  83  
  84          $this->buffer[] = $entry;
  85          $this->count++;
  86  
  87          if (!isset($this->buffersize)) {
  88              $this->buffersize = $this->get_config('buffersize', 50);
  89          }
  90  
  91          if ($this->count >= $this->buffersize) {
  92              $this->flush();
  93          }
  94      }
  95  
  96      /**
  97       * Flush event buffer.
  98       */
  99      public function flush() {
 100          if ($this->count == 0) {
 101              return;
 102          }
 103          $events = $this->buffer;
 104          $this->count = 0;
 105          $this->buffer = array();
 106          $this->insert_event_entries($events);
 107      }
 108  
 109      /**
 110       * Bulk write a given array of events to the backend. Stores must implement this.
 111       *
 112       * @param array $evententries raw event data
 113       */
 114      abstract protected function insert_event_entries($evententries);
 115  
 116      /**
 117       * Get a config value for the store.
 118       *
 119       * @param string $name Config name
 120       * @param mixed $default default value
 121       *
 122       * @return mixed config value if set, else the default value.
 123       */
 124      abstract protected function get_config($name, $default = null);
 125  
 126      /**
 127       * Push any remaining events to the database. Insert_events() must be
 128       * defined. override in stores if the store doesn't support buffering.
 129       *
 130       */
 131      public function dispose() {
 132          $this->flush();
 133      }
 134  }