cohort/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 //
   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  * Privacy class for requesting user data.
  19  *
  20  * @package    core_cohort
  21  * @copyright  2018 Sara Arjona <sara@moodle.com>
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 namespace core_cohort\privacy;
  26
  27 defined('MOODLE_INTERNAL') || die();
  28
  29 use core_privacy\local\metadata\collection;
  30 use core_privacy\local\request\contextlist;
  31 use core_privacy\local\request\approved_contextlist;
  32 use core_privacy\local\request\transform;
  33 use core_privacy\local\request\writer;
  34 use core_privacy\local\request\userlist;
  35 use core_privacy\local\request\approved_userlist;
  36
  37 /**
  38  * Privacy class for requesting user data.
  39  *
  40  * @copyright  2018 Sara Arjona <sara@moodle.com>
  41  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  42  */
  43 class provider implements
  44         \core_privacy\local\metadata\provider,
  45         \core_privacy\local\request\core_userlist_provider,
  46         \core_privacy\local\request\plugin\provider {
  47
  48     /**
  49      * Return the fields which contain personal data.
  50      *
  51      * @param   collection $collection The initialised collection to add items to.
  52      * @return  collection A listing of user data stored through this system.
  53      */
  54     public static function get_metadata(collection $collection) : collection {
  55         $collection->add_database_table('cohort_members', [
  56                 'cohortid' => 'privacy:metadata:cohort_members:cohortid',
  57                 'userid' => 'privacy:metadata:cohort_members:userid',
  58                 'timeadded' => 'privacy:metadata:cohort_members:timeadded'
  59             ], 'privacy:metadata:cohort_members');
  60         return $collection;
  61     }
  62
  63     /**
  64      * Get the list of contexts that contain user information for the specified user.
  65      *
  66      * @param int $userid The user to search.
  67      * @return contextlist $contextlist The contextlist containing the list of contexts used in this plugin.
  68      */
  69     public static function get_contexts_for_userid(int $userid) : contextlist {
  70         $sql = "SELECT ctx.id
  71                   FROM {context} ctx
  72             INNER JOIN {cohort} c ON c.contextid = ctx.id
  73             INNER JOIN {cohort_members} cm ON cm.cohortid = c.id
  74                  WHERE cm.userid = :userid AND (ctx.contextlevel = :contextlevel1 OR ctx.contextlevel = :contextlevel2)";
  75         $params = [
  76             'userid'        => $userid,
  77             'contextlevel1' => CONTEXT_SYSTEM,
  78             'contextlevel2' => CONTEXT_COURSECAT,
  79         ];
  80         $contextlist = new contextlist();
  81         $contextlist->add_from_sql($sql, $params);
  82
  83         return $contextlist;
  84     }
  85
  86     /**
  87      * Get the list of users within a specific context.
  88      *
  89      * @param userlist $userlist The userlist containing the list of users who have data in this context/plugin combination.
  90      */
  91     public static function get_users_in_context(userlist $userlist) {
  92         $context = $userlist->get_context();
  93
  94         if (!$context instanceof \context_system && !$context instanceof \context_coursecat) {
  95             return;
  96         }
  97
  98         $params = [
  99             'contextid' => $context->id,
 100             'contextsystem' => CONTEXT_SYSTEM,
 101             'contextcoursecat' => CONTEXT_COURSECAT,
 102         ];
 103
 104         $sql = "SELECT cm.userid as userid
 105                   FROM {cohort_members} cm
 106                   JOIN {cohort} c
 107                        ON cm.cohortid = c.id
 108                   JOIN {context} ctx
 109                        ON c.contextid = ctx.id
 110                        AND (ctx.contextlevel = :contextsystem
 111                             OR ctx.contextlevel = :contextcoursecat)
 112                  WHERE ctx.id = :contextid";
 113
 114         $userlist->add_from_sql('userid', $sql, $params);
 115     }
 116
 117     /**
 118      * Export all user data for the specified user, in the specified contexts.
 119      *
 120      * @param approved_contextlist $contextlist The approved contexts to export information for.
 121      */
 122     public static function export_user_data(approved_contextlist $contextlist) {
 123         global $DB;
 124
 125         // Remove contexts different from SYSTEM or COURSECAT.
 126         $contexts = array_reduce($contextlist->get_contexts(), function($carry, $context) {
 127             if ($context->contextlevel == CONTEXT_SYSTEM || $context->contextlevel == CONTEXT_COURSECAT) {
 128                 $carry[] = $context->id;
 129             }
 130             return $carry;
 131         }, []);
 132
 133         if (empty($contexts)) {
 134             return;
 135         }
 136
 137         // Get cohort data.
 138         $userid = $contextlist->get_user()->id;
 139         list($contextsql, $contextparams) = $DB->get_in_or_equal($contexts, SQL_PARAMS_NAMED);
 140         $sql = "SELECT c.name,
 141                        c.idnumber,
 142                        c.description,
 143                        c.visible,
 144                        cm.timeadded,
 145                        ctx.id as contextid
 146                   FROM {context} ctx
 147             INNER JOIN {cohort} c ON c.contextid = ctx.id
 148             INNER JOIN {cohort_members} cm ON cm.cohortid = c.id
 149                  WHERE ctx.id {$contextsql}
 150                        AND cm.userid = :userid";
 151         $params = [
 152                 'userid'        => $userid
 153             ] + $contextparams;
 154
 155         $cohorts = $DB->get_recordset_sql($sql, $params);
 156         foreach ($cohorts as $cohort) {
 157             $alldata[$cohort->contextid][] = (object)[
 158                     'name' => $cohort->name,
 159                     'idnumber' => $cohort->idnumber,
 160                     'visible' => transform::yesno($cohort->visible),
 161                     'timeadded' => transform::datetime($cohort->timeadded),
 162                 ];
 163         }
 164         $cohorts->close();
 165
 166         // Export cohort data.
 167         array_walk($alldata, function($data, $contextid) {
 168             $context = \context::instance_by_id($contextid);
 169             writer::with_context($context)->export_related_data([], 'cohort', $data);
 170         });
 171
 172     }
 173
 174     /**
 175      * Delete all use data which matches the specified context.
 176      *
 177      * @param context $context A user context.
 178      */
 179     public static function delete_data_for_all_users_in_context(\context $context) {
 180         if (!$context instanceof \context_system && !$context instanceof \context_coursecat) {
 181             return;
 182         }
 183
 184         static::delete_data($context);
 185     }
 186
 187     /**
 188      * Delete multiple users within a single context.
 189      *
 190      * @param approved_userlist $userlist The approved context and user information to delete information for.
 191      */
 192     public static function delete_data_for_users(approved_userlist $userlist) {
 193         $context = $userlist->get_context();
 194
 195         if ($context instanceof \context_system || $context instanceof \context_coursecat) {
 196             foreach ($userlist->get_userids() as $userid) {
 197                 static::delete_data($context, $userid);
 198             }
 199         }
 200     }
 201
 202     /**
 203      * Delete all user data for the specified user, in the specified contexts.
 204      *
 205      * @param approved_contextlist $contextlist The approved contexts and user information to delete information for.
 206      */
 207     public static function delete_data_for_user(approved_contextlist $contextlist) {
 208         if (empty($contextlist->count())) {
 209             return;
 210         }
 211
 212         $userid = $contextlist->get_user()->id;
 213         foreach ($contextlist->get_contexts() as $context) {
 214             if (!$context instanceof \context_system && !$context instanceof \context_coursecat) {
 215                 continue;
 216             }
 217             static::delete_data($context, $userid);
 218         }
 219     }
 220
 221     /**
 222      * Delete data related to a context and user (if defined).
 223      *
 224      * @param context $context A context.
 225      * @param int $userid The user ID.
 226      */
 227     protected static function delete_data(\context $context, int $userid = null) {
 228         global $DB;
 229
 230         $cohortids = $DB->get_fieldset_select('cohort', 'id', 'contextid = :contextid', ['contextid' => $context->id]);
 231         foreach ($cohortids as $cohortid) {
 232             $params = ['cohortid' => $cohortid];
 233             if (!empty($userid)) {
 234                 $params['userid'] = $userid;
 235             }
 236             $DB->delete_records('cohort_members', $params);
 237         }
 238     }
 239 }