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See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.

Differences Between: [Versions 310 and 401] [Versions 311 and 401] [Versions 39 and 401] [Versions 400 and 401]

   1  <?php
   2  
   3  // This file is part of Moodle - http://moodle.org/
   4  //
   5  // Moodle is free software: you can redistribute it and/or modify
   6  // it under the terms of the GNU General Public License as published by
   7  // the Free Software Foundation, either version 3 of the License, or
   8  // (at your option) any later version.
   9  //
  10  // Moodle is distributed in the hope that it will be useful,
  11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  // GNU General Public License for more details.
  14  //
  15  // You should have received a copy of the GNU General Public License
  16  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17  
  18  /**
  19   * @package    moodlecore
  20   * @subpackage backup-dbops
  21   * @copyright  2010 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  /**
  26   * Non instantiable helper class providing DB support to the backup_structure stuff
  27   *
  28   * This class contains various static methods available for all the DB operations
  29   * performed by the backup_structure stuff (mainly @backup_nested_element class)
  30   *
  31   * TODO: Finish phpdocs
  32   */
  33  abstract class backup_structure_dbops extends backup_dbops {
  34  
  35      public static function get_iterator($element, $params, $processor) {
  36          global $DB;
  37  
  38          // Check we are going to get_iterator for one backup_nested_element
  39          if (! $element instanceof backup_nested_element) {
  40              throw new base_element_struct_exception('backup_nested_element_expected');
  41          }
  42  
  43          // If var_array, table and sql are null, and element has no final elements it is one nested element without source
  44          // Just return one 1 element iterator without information
  45          if ($element->get_source_array() === null && $element->get_source_table() === null &&
  46              $element->get_source_sql() === null && count($element->get_final_elements()) == 0) {
  47              return new backup_array_iterator(array(0 => null));
  48  
  49          } else if ($element->get_source_array() !== null) { // It's one array, return array_iterator
  50              return new backup_array_iterator($element->get_source_array());
  51  
  52          } else if ($element->get_source_table() !== null) { // It's one table, return recordset iterator
  53              return $DB->get_recordset($element->get_source_table(), self::convert_params_to_values($params, $processor), $element->get_source_table_sortby());
  54  
  55          } else if ($element->get_source_sql() !== null) { // It's one sql, return recordset iterator
  56              return $DB->get_recordset_sql($element->get_source_sql(), self::convert_params_to_values($params, $processor));
  57  
  58          } else { // No sources, supress completely, using null iterator
  59              return new backup_null_iterator();
  60          }
  61      }
  62  
  63      public static function convert_params_to_values($params, $processor) {
  64          $newparams = array();
  65          foreach ($params as $key => $param) {
  66              $newvalue = null;
  67              // If we have a base element, get its current value, exception if not set
  68              if ($param instanceof base_atom) {
  69                  if ($param->is_set()) {
  70                      $newvalue = $param->get_value();
  71                  } else {
  72                      throw new base_element_struct_exception('valueofparamelementnotset', $param->get_name());
  73                  }
  74  
  75              } else if (is_int($param) && $param < 0) { // Possibly one processor variable, let's process it
  76                  // See @backup class for all the VAR_XXX variables available.
  77                  // Note1: backup::VAR_PARENTID is handled by nested elements themselves
  78                  // Note2: trying to use one non-existing var will throw exception
  79                  $newvalue = $processor->get_var($param);
  80  
  81              // Else we have one raw param value, use it
  82              } else {
  83                  $newvalue = $param;
  84              }
  85  
  86              $newparams[$key] = $newvalue;
  87          }
  88          return $newparams;
  89      }
  90  
  91      public static function insert_backup_ids_record($backupid, $itemname, $itemid) {
  92          global $DB;
  93          // We need to do some magic with scales (that are stored in negative way)
  94          if ($itemname == 'scale') {
  95              $itemid = -($itemid);
  96          }
  97          // Now, we skip any annotation with negatives/zero/nulls, ids table only stores true id (always > 0)
  98          if ($itemid <= 0 || is_null($itemid)) {
  99              return;
 100          }
 101          // TODO: Analyze if some static (and limited) cache by the 3 params could save us a bunch of record_exists() calls
 102          // Note: Sure it will!
 103          if (!$DB->record_exists('backup_ids_temp', array('backupid' => $backupid, 'itemname' => $itemname, 'itemid' => $itemid))) {
 104              $DB->insert_record('backup_ids_temp', array('backupid' => $backupid, 'itemname' => $itemname, 'itemid' => $itemid));
 105          }
 106      }
 107  
 108      /**
 109       * Adds backup id database record for all files in the given file area.
 110       *
 111       * @param string $backupid Backup ID
 112       * @param int $contextid Context id
 113       * @param string $component Component
 114       * @param string $filearea File area
 115       * @param int $itemid Item id
 116       * @param \core\progress\base $progress
 117       */
 118      public static function annotate_files($backupid, $contextid, $component, $filearea, $itemid,
 119              \core\progress\base $progress = null) {
 120          global $DB;
 121          $sql = 'SELECT id
 122                    FROM {files}
 123                   WHERE contextid = ?
 124                     AND component = ?';
 125          $params = array($contextid, $component);
 126  
 127          if (!is_null($filearea)) { // Add filearea to query and params if necessary
 128              $sql .= ' AND filearea = ?';
 129              $params[] = $filearea;
 130          }
 131  
 132          if (!is_null($itemid)) { // Add itemid to query and params if necessary
 133              $sql .= ' AND itemid = ?';
 134              $params[] = $itemid;
 135          }
 136          if ($progress) {
 137              $progress->start_progress('');
 138          }
 139          $rs = $DB->get_recordset_sql($sql, $params);
 140          foreach ($rs as $record) {
 141              if ($progress) {
 142                  $progress->progress();
 143              }
 144              self::insert_backup_ids_record($backupid, 'file', $record->id);
 145          }
 146          if ($progress) {
 147              $progress->end_progress();
 148          }
 149          $rs->close();
 150      }
 151  
 152      /**
 153       * Moves all the existing 'item' annotations to their final 'itemfinal' ones
 154       * for a given backup.
 155       *
 156       * @param string $backupid Backup ID
 157       * @param string $itemname Item name
 158       * @param \core\progress\base $progress Progress tracker
 159       */
 160      public static function move_annotations_to_final($backupid, $itemname, \core\progress\base $progress) {
 161          global $DB;
 162          $progress->start_progress('move_annotations_to_final');
 163          $rs = $DB->get_recordset('backup_ids_temp', array('backupid' => $backupid, 'itemname' => $itemname));
 164          $progress->progress();
 165          foreach($rs as $annotation) {
 166              // If corresponding 'itemfinal' annotation does not exist, update 'item' to 'itemfinal'
 167              if (! $DB->record_exists('backup_ids_temp', array('backupid' => $backupid,
 168                                                                'itemname' => $itemname . 'final',
 169                                                                'itemid' => $annotation->itemid))) {
 170                  $DB->set_field('backup_ids_temp', 'itemname', $itemname . 'final', array('id' => $annotation->id));
 171              }
 172              $progress->progress();
 173          }
 174          $rs->close();
 175          // All the remaining $itemname annotations can be safely deleted
 176          $DB->delete_records('backup_ids_temp', array('backupid' => $backupid, 'itemname' => $itemname));
 177          $progress->end_progress();
 178      }
 179  
 180      /**
 181       * Returns true/false if there are annotations for a given item
 182       */
 183      public static function annotations_exist($backupid, $itemname) {
 184          global $DB;
 185          return (bool)$DB->count_records('backup_ids_temp', array('backupid' => $backupid, 'itemname' => $itemname));
 186      }
 187  }