mod/choice/classes/privacy/provider.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 //
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  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  * Privacy Subsystem implementation for mod_choice.
  19  *
  20  * @package    mod_choice
  21  * @copyright  2018 Jun Pataleta
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 namespace mod_choice\privacy;
  26
  27 use core_privacy\local\metadata\collection;
  28 use core_privacy\local\request\approved_contextlist;
  29 use core_privacy\local\request\contextlist;
  30 use core_privacy\local\request\deletion_criteria;
  31 use core_privacy\local\request\helper;
  32 use core_privacy\local\request\writer;
  33
  34 defined('MOODLE_INTERNAL') || die();
  35
  36 /**
  37  * Implementation of the privacy subsystem plugin provider for the choice activity module.
  38  *
  39  * @copyright  2018 Jun Pataleta
  40  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  41  */
  42 class provider implements
  43         // This plugin stores personal data.
  44         \core_privacy\local\metadata\provider,
  45
  46         // This plugin is a core_user_data_provider.
  47         \core_privacy\local\request\plugin\provider {
  48     /**
  49      * Return the fields which contain personal data.
  50      *
  51      * @param collection $items a reference to the collection to use to store the metadata.
  52      * @return collection the updated collection of metadata items.
  53      */
  54     public static function get_metadata(collection $items) : collection {
  55         $items->add_database_table(
  56             'choice_answers',
  57             [
  58                 'choiceid' => 'privacy:metadata:choice_answers:choiceid',
  59                 'optionid' => 'privacy:metadata:choice_answers:optionid',
  60                 'userid' => 'privacy:metadata:choice_answers:userid',
  61                 'timemodified' => 'privacy:metadata:choice_answers:timemodified',
  62             ],
  63             'privacy:metadata:choice_answers'
  64         );
  65
  66         return $items;
  67     }
  68
  69     /**
  70      * Get the list of contexts that contain user information for the specified user.
  71      *
  72      * @param int $userid the userid.
  73      * @return contextlist the list of contexts containing user info for the user.
  74      */
  75     public static function get_contexts_for_userid(int $userid) : contextlist {
  76         // Fetch all choice answers.
  77         $sql = "SELECT c.id
  78                   FROM {context} c
  79             INNER JOIN {course_modules} cm ON cm.id = c.instanceid AND c.contextlevel = :contextlevel
  80             INNER JOIN {modules} m ON m.id = cm.module AND m.name = :modname
  81             INNER JOIN {choice} ch ON ch.id = cm.instance
  82             INNER JOIN {choice_options} co ON co.choiceid = ch.id
  83             INNER JOIN {choice_answers} ca ON ca.optionid = co.id AND ca.choiceid = ch.id
  84                  WHERE ca.userid = :userid";
  85
  86         $params = [
  87             'modname'       => 'choice',
  88             'contextlevel'  => CONTEXT_MODULE,
  89             'userid'        => $userid,
  90         ];
  91         $contextlist = new contextlist();
  92         $contextlist->add_from_sql($sql, $params);
  93
  94         return $contextlist;
  95     }
  96
  97     /**
  98      * Export personal data for the given approved_contextlist. User and context information is contained within the contextlist.
  99      *
 100      * @param approved_contextlist $contextlist a list of contexts approved for export.
 101      */
 102     public static function export_user_data(approved_contextlist $contextlist) {
 103         global $DB;
 104
 105         if (empty($contextlist->count())) {
 106             return;
 107         }
 108
 109         $user = $contextlist->get_user();
 110
 111         list($contextsql, $contextparams) = $DB->get_in_or_equal($contextlist->get_contextids(), SQL_PARAMS_NAMED);
 112
 113         $sql = "SELECT cm.id AS cmid,
 114                        co.text as answer,
 115                        ca.timemodified
 116                   FROM {context} c
 117             INNER JOIN {course_modules} cm ON cm.id = c.instanceid AND c.contextlevel = :contextlevel
 118             INNER JOIN {modules} m ON m.id = cm.module AND m.name = :modname
 119             INNER JOIN {choice} ch ON ch.id = cm.instance
 120             INNER JOIN {choice_options} co ON co.choiceid = ch.id
 121             INNER JOIN {choice_answers} ca ON ca.optionid = co.id AND ca.choiceid = ch.id
 122                  WHERE c.id {$contextsql}
 123                        AND ca.userid = :userid
 124               ORDER BY cm.id";
 125
 126         $params = ['modname' => 'choice', 'contextlevel' => CONTEXT_MODULE, 'userid' => $user->id] + $contextparams;
 127
 128         // Reference to the choice activity seen in the last iteration of the loop. By comparing this with the current record, and
 129         // because we know the results are ordered, we know when we've moved to the answers for a new choice activity and therefore
 130         // when we can export the complete data for the last activity.
 131         $lastcmid = null;
 132
 133         $choiceanswers = $DB->get_recordset_sql($sql, $params);
 134         foreach ($choiceanswers as $choiceanswer) {
 135             // If we've moved to a new choice, then write the last choice data and reinit the choice data array.
 136             if ($lastcmid != $choiceanswer->cmid) {
 137                 if (!empty($choicedata)) {
 138                     $context = \context_module::instance($lastcmid);
 139                     self::export_choice_data_for_user($choicedata, $context, $user);
 140                 }
 141                 $choicedata = [
 142                     'answer' => [],
 143                     'timemodified' => \core_privacy\local\request\transform::datetime($choiceanswer->timemodified),
 144                 ];
 145             }
 146             $choicedata['answer'][] = $choiceanswer->answer;
 147             $lastcmid = $choiceanswer->cmid;
 148         }
 149         $choiceanswers->close();
 150
 151         // The data for the last activity won't have been written yet, so make sure to write it now!
 152         if (!empty($choicedata)) {
 153             $context = \context_module::instance($lastcmid);
 154             self::export_choice_data_for_user($choicedata, $context, $user);
 155         }
 156     }
 157
 158     /**
 159      * Export the supplied personal data for a single choice activity, along with any generic data or area files.
 160      *
 161      * @param array $choicedata the personal data to export for the choice.
 162      * @param \context_module $context the context of the choice.
 163      * @param \stdClass $user the user record
 164      */
 165     protected static function export_choice_data_for_user(array $choicedata, \context_module $context, \stdClass $user) {
 166         // Fetch the generic module data for the choice.
 167         $contextdata = helper::get_context_data($context, $user);
 168
 169         // Merge with choice data and write it.
 170         $contextdata = (object)array_merge((array)$contextdata, $choicedata);
 171         writer::with_context($context)->export_data([], $contextdata);
 172
 173         // Write generic module intro files.
 174         helper::export_context_files($context, $user);
 175     }
 176
 177     /**
 178      * Delete all data for all users in the specified context.
 179      *
 180      * @param \context $context the context to delete in.
 181      */
 182     public static function delete_data_for_all_users_in_context(\context $context) {
 183         global $DB;
 184
 185         if (!$context instanceof \context_module) {
 186             return;
 187         }
 188
 189         if ($cm = get_coursemodule_from_id('choice', $context->instanceid)) {
 190             $DB->delete_records('choice_answers', ['choiceid' => $cm->instance]);
 191         }
 192     }
 193
 194     /**
 195      * Delete all user data for the specified user, in the specified contexts.
 196      *
 197      * @param approved_contextlist $contextlist a list of contexts approved for deletion.
 198      */
 199     public static function delete_data_for_user(approved_contextlist $contextlist) {
 200         global $DB;
 201
 202         if (empty($contextlist->count())) {
 203             return;
 204         }
 205
 206         $userid = $contextlist->get_user()->id;
 207         foreach ($contextlist->get_contexts() as $context) {
 208
 209             if (!$context instanceof \context_module) {
 210                 continue;
 211             }
 212             $instanceid = $DB->get_field('course_modules', 'instance', ['id' => $context->instanceid], MUST_EXIST);
 213             $DB->delete_records('choice_answers', ['choiceid' => $instanceid, 'userid' => $userid]);
 214         }
 215     }
 216 }