Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Privacy Subsystem implementation for core_backup.

 *

 * @package    core_backup

 * @copyright  2018 Mark Nelson <markn@moodle.com>

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

namespace core_backup\privacy;

use core_privacy\local\metadata\collection;

use core_privacy\local\request\approved_contextlist;

use core_privacy\local\request\contextlist;

use core_privacy\local\request\transform;

use core_privacy\local\request\writer;

use core_privacy\local\request\userlist;

use core_privacy\local\request\approved_userlist;

defined('MOODLE_INTERNAL') || die();

require_once($CFG->dirroot . '/backup/util/includes/backup_includes.php');

/**

 * Privacy Subsystem implementation for core_backup.

 *

 * @copyright  2018 Mark Nelson <markn@moodle.com>

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class provider implements

    \core_privacy\local\metadata\provider,

    \core_privacy\local\request\core_userlist_provider,

    \core_privacy\local\request\subsystem\provider {

    /**

     * Return the fields which contain personal data.

     *

     * @param collection $items a reference to the collection to use to store the metadata.

     * @return collection the updated collection of metadata items.

     */

    public static function get_metadata(collection $items): collection {

        $items->link_external_location(

            'Backup',

            [

                'detailsofarchive' => 'privacy:metadata:backup:detailsofarchive'

            ],

            'privacy:metadata:backup:externalpurpose'

        );

        $items->add_database_table(

            'backup_controllers',

            [

                'operation' => 'privacy:metadata:backup_controllers:operation',

                'type' => 'privacy:metadata:backup_controllers:type',

                'itemid' => 'privacy:metadata:backup_controllers:itemid',

                'timecreated' => 'privacy:metadata:backup_controllers:timecreated',

                'timemodified' => 'privacy:metadata:backup_controllers:timemodified'

            ],

            'privacy:metadata:backup_controllers'

        );

        return $items;

    }

    /**

     * Get the list of contexts that contain user information for the specified user.

     *

     * @param int $userid The user to search.

     * @return contextlist The contextlist containing the list of contexts used in this plugin.

     */

    public static function get_contexts_for_userid(int $userid): contextlist {

        $contextlist = new contextlist();

        $sql = "SELECT ctx.id

                  FROM {backup_controllers} bc

                  JOIN {context} ctx

                        ON ctx.instanceid = bc.itemid

                       AND ctx.contextlevel = :contextlevel

                       AND bc.type = :type

                 WHERE bc.userid = :userid";

        $params = [

            'contextlevel' => CONTEXT_COURSE,

            'userid' => $userid,

            'type' => 'course',

        ];

        $contextlist->add_from_sql($sql, $params);

        $sql = "SELECT ctx.id

                  FROM {backup_controllers} bc

                  JOIN {course_sections} c

                        ON bc.itemid = c.id

                       AND bc.type = :type

                  JOIN {context} ctx

                        ON ctx.instanceid = c.course

                       AND ctx.contextlevel = :contextlevel

                 WHERE bc.userid = :userid";

        $params = [

            'contextlevel' => CONTEXT_COURSE,

            'userid' => $userid,

            'type' => 'section',

        ];

        $contextlist->add_from_sql($sql, $params);

        $sql = "SELECT ctx.id

                  FROM {backup_controllers} bc

                  JOIN {context} ctx

                        ON ctx.instanceid = bc.itemid

                       AND ctx.contextlevel = :contextlevel

                       AND bc.type = :type

                 WHERE bc.userid = :userid";

        $params = [

            'contextlevel' => CONTEXT_MODULE,

            'userid' => $userid,

            'type' => 'activity',

        ];

        $contextlist->add_from_sql($sql, $params);

        return $contextlist;

    }

    /**

     * Get the list of users within a specific context.

     *

     * @param userlist $userlist The userlist containing the list of users who have data in this context/plugin combination.

     */

    public static function get_users_in_context(userlist $userlist) {

        $context = $userlist->get_context();

        if ($context instanceof \context_course) {

            $params = ['courseid' => $context->instanceid];

            $sql = "SELECT bc.userid

                      FROM {backup_controllers} bc

                     WHERE bc.itemid = :courseid

                           AND bc.type = :typecourse";

            $courseparams = ['typecourse' => 'course'] + $params;

            $userlist->add_from_sql('userid', $sql, $courseparams);

            $sql = "SELECT bc.userid

                      FROM {backup_controllers} bc

                      JOIN {course_sections} c

                           ON bc.itemid = c.id

                     WHERE c.course = :courseid

                           AND bc.type = :typesection";

            $sectionparams = ['typesection' => 'section'] + $params;

            $userlist->add_from_sql('userid', $sql, $sectionparams);

        }

        if ($context instanceof \context_module) {

            $params = [

                'cmid' => $context->instanceid,

                'typeactivity' => 'activity'

            ];

            $sql = "SELECT bc.userid

                      FROM {backup_controllers} bc

                     WHERE bc.itemid = :cmid

                           AND bc.type = :typeactivity";

            $userlist->add_from_sql('userid', $sql, $params);

        }

    }

    /**

     * Export all user data for the specified user, in the specified contexts.

     *

     * @param approved_contextlist $contextlist The approved contexts to export information for.

     */

    public static function export_user_data(approved_contextlist $contextlist) {

        global $DB;

        if (empty($contextlist->count())) {

            return;

        }

        $user = $contextlist->get_user();

        list($contextsql, $contextparams) = $DB->get_in_or_equal($contextlist->get_contextids(), SQL_PARAMS_NAMED);

        $sql = "SELECT bc.*

                  FROM {backup_controllers} bc

                  JOIN {context} ctx

                    ON ctx.instanceid = bc.itemid AND ctx.contextlevel = :contextlevel

                 WHERE ctx.id {$contextsql}

                   AND bc.userid = :userid

              ORDER BY bc.timecreated ASC";

        $params = ['contextlevel' => CONTEXT_COURSE, 'userid' => $user->id] + $contextparams;

        $backupcontrollers = $DB->get_recordset_sql($sql, $params);

        self::recordset_loop_and_export($backupcontrollers, 'itemid', [], function($carry, $record) {

            $carry[] = [

                'operation' => $record->operation,

                'type' => $record->type,

                'itemid' => $record->itemid,

                'timecreated' => transform::datetime($record->timecreated),

                'timemodified' => transform::datetime($record->timemodified),

            ];

            return $carry;

        }, function($courseid, $data) {

            $context = \context_course::instance($courseid);

            $finaldata = (object) $data;

            writer::with_context($context)->export_data([get_string('backup'), $courseid], $finaldata);

        });

    }

    /**

     * Delete all user data which matches the specified context.

     * Only dealing with the specific context - not it's child contexts.

     *

     * @param \context $context A user context.

     */

    public static function delete_data_for_all_users_in_context(\context $context) {

        global $DB;

        if ($context instanceof \context_course) {

            $sectionsql = "itemid IN (SELECT id FROM {course_sections} WHERE course = ?) AND type = ?";

            $DB->delete_records_select('backup_controllers', $sectionsql, [$context->instanceid, \backup::TYPE_1SECTION]);

            $DB->delete_records('backup_controllers', ['itemid' => $context->instanceid, 'type' => \backup::TYPE_1COURSE]);

        }

        if ($context instanceof \context_module) {

            $DB->delete_records('backup_controllers', ['itemid' => $context->instanceid, 'type' => \backup::TYPE_1ACTIVITY]);

        }

        return;

    }

    /**

     * Delete multiple users within a single context.

     * Only dealing with the specific context - not it's child contexts.

     *

     * @param approved_userlist $userlist The approved context and user information to delete information for.

     */

    public static function delete_data_for_users(approved_userlist $userlist) {

        global $DB;

        if (empty($userlist->get_userids())) {

            return;

        }

        $context = $userlist->get_context();

        if ($context instanceof \context_course) {

            list($usersql, $userparams) = $DB->get_in_or_equal($userlist->get_userids(), SQL_PARAMS_NAMED);

            $select = "itemid = :itemid AND userid {$usersql} AND type = :type";

            $params = $userparams;

            $params['itemid'] = $context->instanceid;

            $params['type'] = \backup::TYPE_1COURSE;

            $DB->delete_records_select('backup_controllers', $select, $params);

            $params = $userparams;

            $params['course'] = $context->instanceid;

            $params['type'] = \backup::TYPE_1SECTION;

            $sectionsql = "itemid IN (SELECT id FROM {course_sections} WHERE course = :course)";

            $select = $sectionsql . " AND userid {$usersql} AND type = :type";

            $DB->delete_records_select('backup_controllers', $select, $params);

        }

        if ($context instanceof \context_module) {

            list($usersql, $userparams) = $DB->get_in_or_equal($userlist->get_userids(), SQL_PARAMS_NAMED);

            $select = "itemid = :itemid AND userid {$usersql} AND type = :type";

            $params = $userparams;

            $params['itemid'] = $context->instanceid;

            $params['type'] = \backup::TYPE_1ACTIVITY;

            // Delete activity backup data.

            $select = "itemid = :itemid AND type = :type AND userid {$usersql}";

            $params = ['itemid' => $context->instanceid, 'type' => 'activity'] + $userparams;

            $DB->delete_records_select('backup_controllers', $select, $params);

        }

    }

    /**

     * Delete all user data for the specified user, in the specified contexts.

     * Only dealing with the specific context - not it's child contexts.

     *

     * @param approved_contextlist $contextlist The approved contexts and user information to delete information for.

     */

    public static function delete_data_for_user(approved_contextlist $contextlist) {

        global $DB;

        if (empty($contextlist->count())) {

            return;

        }

        $userid = $contextlist->get_user()->id;

        foreach ($contextlist->get_contexts() as $context) {

            if ($context instanceof \context_course) {

                $select = "itemid = :itemid AND userid = :userid AND type = :type";

                $params = [

                    'userid' => $userid,

                    'itemid' => $context->instanceid,

                    'type' => \backup::TYPE_1COURSE

                ];

                $DB->delete_records_select('backup_controllers', $select, $params);

                $params = [

                    'userid' => $userid,

                    'course' => $context->instanceid,

                    'type' => \backup::TYPE_1SECTION

                ];

                $sectionsql = "itemid IN (SELECT id FROM {course_sections} WHERE course = :course)";

                $select = $sectionsql . " AND userid = :userid AND type = :type";

                $DB->delete_records_select('backup_controllers', $select, $params);

            }

            if ($context instanceof \context_module) {

                list($usersql, $userparams) = $DB->get_in_or_equal($userlist->get_userids(), SQL_PARAMS_NAMED);

                $select = "itemid = :itemid AND userid = :userid AND type = :type";

                $params = [

                    'itemid' => $context->instanceid,

                    'userid' => $userid,

                    'type' => \backup::TYPE_1ACTIVITY

                ];

                $DB->delete_records_select('backup_controllers', $select, $params);

            }

        }

    }

    /**

     * Loop and export from a recordset.

     *

     * @param \moodle_recordset $recordset The recordset.

     * @param string $splitkey The record key to determine when to export.

     * @param mixed $initial The initial data to reduce from.

     * @param callable $reducer The function to return the dataset, receives current dataset, and the current record.

     * @param callable $export The function to export the dataset, receives the last value from $splitkey and the dataset.

     * @return void

     */

    protected static function recordset_loop_and_export(\moodle_recordset $recordset, $splitkey, $initial,

            callable $reducer, callable $export) {

        $data = $initial;

        $lastid = null;

        foreach ($recordset as $record) {

            if ($lastid && $record->{$splitkey} != $lastid) {

                $export($lastid, $data);

                $data = $initial;

            }

            $data = $reducer($data, $record);

            $lastid = $record->{$splitkey};

        }

        $recordset->close();

        if (!empty($lastid)) {

            $export($lastid, $data);

        }

    }

}