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 enrol_lti.

 *

 * @package    enrol_lti

 * @category   privacy

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

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

 */

namespace enrol_lti\privacy;

use core_privacy\local\metadata\collection;

use core_privacy\local\request\approved_contextlist;

use core_privacy\local\request\approved_userlist;

use core_privacy\local\request\contextlist;

use core_privacy\local\request\transform;

use core_privacy\local\request\userlist;

use core_privacy\local\request\writer;

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

/**

 * Privacy Subsystem for enrol_lti.

 *

 * @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\plugin\provider,

    \core_privacy\local\request\core_userlist_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->add_database_table(

            'enrol_lti_users',

            [

                'userid' => 'privacy:metadata:enrol_lti_users:userid',

                'lastgrade' => 'privacy:metadata:enrol_lti_users:lastgrade',

                'lastaccess' => 'privacy:metadata:enrol_lti_users:lastaccess',

                'timecreated' => 'privacy:metadata:enrol_lti_users:timecreated'

            ],

            'privacy:metadata:enrol_lti_users'

        );

        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 DISTINCT ctx.id

                  FROM {enrol_lti_users} ltiusers

                  JOIN {enrol_lti_tools} ltitools

                    ON ltiusers.toolid = ltitools.id

                  JOIN {context} ctx

                    ON ctx.id = ltitools.contextid

                 WHERE ltiusers.userid = :userid";

        $params = ['userid' => $userid];

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

        return $contextlist;

    }

    /**

     * Get the list of users who have data within a 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 || $context instanceof \context_module)) {

            return;

        }

        $sql = "SELECT ltiusers.userid

                  FROM {enrol_lti_users} ltiusers

                  JOIN {enrol_lti_tools} ltitools ON ltiusers.toolid = ltitools.id

                 WHERE ltitools.contextid = :contextid";

        $params = ['contextid' => $context->id];

        $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 ltiusers.lastgrade, ltiusers.lastaccess, ltiusers.timecreated, ltitools.contextid

                  FROM {enrol_lti_users} ltiusers

                  JOIN {enrol_lti_tools} ltitools

                    ON ltiusers.toolid = ltitools.id

                  JOIN {context} ctx

                    ON ctx.id = ltitools.contextid

                 WHERE ctx.id {$contextsql}

                   AND ltiusers.userid = :userid";

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

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

        self::recordset_loop_and_export($ltiusers, 'contextid', [], function($carry, $record) {

            $carry[] = [

                'lastgrade' => $record->lastgrade,

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

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

            ];

            return $carry;

        }, function($contextid, $data) {

            $context = \context::instance_by_id($contextid);

            $finaldata = (object) $data;

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

        });

    }

    /**

     * Delete all user data which matches the specified context.

     *

     * @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 || $context instanceof \context_module)) {

            return;

        }

        $enrolltitools = $DB->get_fieldset_select('enrol_lti_tools', 'id', 'contextid = :contextid',

            ['contextid' => $context->id]);

        if (!empty($enrolltitools)) {

            list($sql, $params) = $DB->get_in_or_equal($enrolltitools, SQL_PARAMS_NAMED);

            $DB->delete_records_select('enrol_lti_users', 'toolid ' . $sql, $params);

        }

    }

    /**

     * Delete all user data for the specified user, in the specified 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;

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

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

            if (!($context instanceof \context_course || $context instanceof \context_module)) {

                continue;

            }

            $enrolltitools = $DB->get_fieldset_select('enrol_lti_tools', 'id', 'contextid = :contextid',

                ['contextid' => $context->id]);

            if (!empty($enrolltitools)) {

                list($sql, $params) = $DB->get_in_or_equal($enrolltitools, SQL_PARAMS_NAMED);

                $params = array_merge($params, ['userid' => $userid]);

                $DB->delete_records_select('enrol_lti_users', "toolid $sql AND userid = :userid", $params);

            }

        }

    }

    /**

     * Delete multiple users within a single context.

     *

     * @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;

        $context = $userlist->get_context();

        if (!($context instanceof \context_course || $context instanceof \context_module)) {

            return;

        }

        $enrolltitools = $DB->get_fieldset_select('enrol_lti_tools', 'id', 'contextid = :contextid',

                ['contextid' => $context->id]);

        if (!empty($enrolltitools)) {

            list($toolsql, $toolparams) = $DB->get_in_or_equal($enrolltitools, SQL_PARAMS_NAMED);

            $userids = $userlist->get_userids();

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

            $params = $toolparams + $userparams;

            $DB->delete_records_select('enrol_lti_users', "toolid $toolsql AND userid $usersql", $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);

        }

    }

}