admin/tool/dataprivacy/classes/expired_contexts_manager.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  * Expired contexts manager.
  19  *
  20  * @package    tool_dataprivacy
  21  * @copyright  2018 David Monllao
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24 namespace tool_dataprivacy;
  25
  26 use tool_dataprivacy\api;
  27 use tool_dataprivacy\purpose;
  28 use tool_dataprivacy\context_instance;
  29 use tool_dataprivacy\data_registry;
  30 use tool_dataprivacy\expired_context;
  31
  32 defined('MOODLE_INTERNAL') || die();
  33
  34 /**
  35  * Expired contexts manager.
  36  *
  37  * @copyright  2018 David Monllao
  38  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  39  */
  40 abstract class expired_contexts_manager {
  41
  42     /**
  43      * Number of deleted contexts for each scheduled task run.
  44      */
  45     const DELETE_LIMIT = 200;
  46
  47     /**
  48      * Returns the list of expired context instances.
  49      *
  50      * @return \stdClass[]
  51      */
  52     abstract protected function get_expired_contexts();
  53
  54     /**
  55      * Specify with context levels this expired contexts manager is deleting.
  56      *
  57      * @return int[]
  58      */
  59     abstract protected function get_context_levels();
  60
  61     /**
  62      * Flag expired contexts as expired.
  63      *
  64      * @return int The number of contexts flagged as expired.
  65      */
  66     public function flag_expired() {
  67
  68         if (!$this->check_requirements()) {
  69             return 0;
  70         }
  71
  72         $contexts = $this->get_expired_contexts();
  73         foreach ($contexts as $context) {
  74             api::create_expired_context($context->id);
  75         }
  76
  77         return count($contexts);
  78     }
  79
  80     /**
  81      * Deletes the expired contexts.
  82      *
  83      * @return int The number of deleted contexts.
  84      */
  85     public function delete() {
  86
  87         $numprocessed = 0;
  88
  89         if (!$this->check_requirements()) {
  90             return $numprocessed;
  91         }
  92
  93         $privacymanager = new \core_privacy\manager();
  94         $privacymanager->set_observer(new \tool_dataprivacy\manager_observer());
  95
  96         foreach ($this->get_context_levels() as $level) {
  97
  98             $expiredcontexts = expired_context::get_records_by_contextlevel($level, expired_context::STATUS_APPROVED);
  99
 100             foreach ($expiredcontexts as $expiredctx) {
 101
 102                 if (!$this->delete_expired_context($privacymanager, $expiredctx)) {
 103                     continue;
 104                 }
 105
 106                 $numprocessed += 1;
 107                 if ($numprocessed == self::DELETE_LIMIT) {
 108                     // Close the recordset.
 109                     $expiredcontexts->close();
 110                     break 2;
 111                 }
 112             }
 113         }
 114
 115         return $numprocessed;
 116     }
 117
 118     /**
 119      * Deletes user data from the provided context.
 120      *
 121      * @param \core_privacy\manager $privacymanager
 122      * @param \tool_dataprivacy\expired_context $expiredctx
 123      * @return \context|false
 124      */
 125     protected function delete_expired_context(\core_privacy\manager $privacymanager, \tool_dataprivacy\expired_context $expiredctx) {
 126
 127         $context = \context::instance_by_id($expiredctx->get('contextid'), IGNORE_MISSING);
 128         if (!$context) {
 129             api::delete_expired_context($expiredctx->get('contextid'));
 130             return false;
 131         }
 132
 133         if (!PHPUNIT_TEST) {
 134             mtrace('Deleting context ' . $context->id . ' - ' .
 135                 shorten_text($context->get_context_name(true, true)));
 136         }
 137
 138         $privacymanager->delete_data_for_all_users_in_context($context);
 139         api::set_expired_context_status($expiredctx, expired_context::STATUS_CLEANED);
 140
 141         return $context;
 142     }
 143
 144     /**
 145      * Check that the requirements to start deleting contexts are satisified.
 146      *
 147      * @return bool
 148      */
 149     protected function check_requirements() {
 150         api::check_can_manage_data_registry(\context_system::instance()->id);
 151
 152         if (!data_registry::defaults_set()) {
 153             return false;
 154         }
 155         return true;
 156     }
 157 }