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 mod_customcert.

 *

 * @package    mod_customcert

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

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

 */

namespace mod_customcert\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\helper;

use core_privacy\local\request\transform;

use core_privacy\local\request\userlist;

use core_privacy\local\request\writer;

/**

 * Privacy Subsystem implementation for mod_customcert.

 *

 * @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(

            'customcert_issues',

            [

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

                'customcertid' => 'privacy:metadata:customcert_issues:customcertid',

                'code' => 'privacy:metadata:customcert_issues:code',

                'emailed' => 'privacy:metadata:customcert_issues:emailed',

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

            ],

            'privacy:metadata:customcert_issues'

        );

        return $items;

    }

    /**

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

     *

     * @param int $userid the userid.

     * @return contextlist the list of contexts containing user info for the user.

     */

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

        $sql = "SELECT c.id

                  FROM {context} c

            INNER JOIN {course_modules} cm

                    ON cm.id = c.instanceid

                   AND c.contextlevel = :contextlevel

            INNER JOIN {modules} m

                    ON m.id = cm.module

                   AND m.name = :modulename

            INNER JOIN {customcert} customcert

                    ON customcert.id = cm.instance

            INNER JOIN {customcert_issues} customcertissues

                    ON customcertissues.customcertid = customcert.id

                 WHERE customcertissues.userid = :userid";

        $params = [

            'modulename' => 'customcert',

            'contextlevel' => CONTEXT_MODULE,

            'userid' => $userid,

        ];

        $contextlist = new contextlist();

        $contextlist->add_from_sql($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_module) {

            return;

        }

        // Fetch all users who have a custom certificate.

        $sql = "SELECT customcertissues.userid

                  FROM {course_modules} cm

                  JOIN {modules} m

                    ON m.id = cm.module AND m.name = :modname

                  JOIN {customcert} customcert

                    ON customcert.id = cm.instance

                  JOIN {customcert_issues} customcertissues

                    ON customcertissues.customcertid = customcert.id

                 WHERE cm.id = :cmid";

        $params = [

            'cmid'      => $context->instanceid,

            'modname'   => 'customcert',

        ];

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

    }

    /**

     * Export personal data for the given approved_contextlist. User and context information is contained within the contextlist.

     *

     * @param approved_contextlist $contextlist a list of contexts approved for export.

     */

    public static function export_user_data(approved_contextlist $contextlist) {

        global $DB;

        // Filter out any contexts that are not related to modules.

        $cmids = array_reduce($contextlist->get_contexts(), function($carry, $context) {

            if ($context->contextlevel == CONTEXT_MODULE) {

                $carry[] = $context->instanceid;

            }

            return $carry;

        }, []);

        if (empty($cmids)) {

            return;

        }

        $user = $contextlist->get_user();

        // Get all the customcert activities associated with the above course modules.

        $customcertidstocmids = self::get_customcert_ids_to_cmids_from_cmids($cmids);

        list($insql, $inparams) = $DB->get_in_or_equal(array_keys($customcertidstocmids), SQL_PARAMS_NAMED);

        $params = array_merge($inparams, ['userid' => $user->id]);

        $recordset = $DB->get_recordset_select('customcert_issues', "customcertid $insql AND userid = :userid",

            $params, 'timecreated, id ASC');

        self::recordset_loop_and_export($recordset, 'customcertid', [], function($carry, $record) {

            $carry[] = [

                'code' => $record->code,

                'emailed' => transform::yesno($record->emailed),

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

            ];

            return $carry;

        }, function($customcertid, $data) use ($user, $customcertidstocmids) {

            $context = \context_module::instance($customcertidstocmids[$customcertid]);

            $contextdata = helper::get_context_data($context, $user);

            $finaldata = (object) array_merge((array) $contextdata, ['issues' => $data]);

            helper::export_context_files($context, $user);

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

        });

    }

    /**

     * Delete all data for all users in the specified context.

     *

     * @param \context $context the context to delete in.

     */

    public static function delete_data_for_all_users_in_context(\context $context) {

        global $DB;

        if (!$context instanceof \context_module) {

            return;

        }

        if (!$cm = get_coursemodule_from_id('customcert', $context->instanceid)) {

            return;

        }

        $DB->delete_records('customcert_issues', ['customcertid' => $cm->instance]);

    }

    /**

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

     *

     * @param approved_contextlist $contextlist a list of contexts approved for deletion.

     */

    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_module) {

                continue;

            }

            $instanceid = $DB->get_field('course_modules', 'instance', ['id' => $context->instanceid], MUST_EXIST);

            $DB->delete_records('customcert_issues', ['customcertid' => $instanceid, 'userid' => $userid]);

        }

    }

    /**

     * 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_module) {

            return;

        }

        $cm = get_coursemodule_from_id('customcert', $context->instanceid);

        if (!$cm) {

            // Only customcert module will be handled.

            return;

        }

        $userids = $userlist->get_userids();

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

        $select = "customcertid = :customcertid AND userid $usersql";

        $params = ['customcertid' => $cm->instance] + $userparams;

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

    }

    /**

     * Return a list of Customcert IDs mapped to their course module ID.

     *

     * @param array $cmids The course module IDs.

     * @return array In the form of [$customcertid => $cmid].

     */

    protected static function get_customcert_ids_to_cmids_from_cmids(array $cmids) {

        global $DB;

        list($insql, $inparams) = $DB->get_in_or_equal($cmids, SQL_PARAMS_NAMED);

        $sql = "SELECT customcert.id, cm.id AS cmid

                 FROM {customcert} customcert

                 JOIN {modules} m

                   ON m.name = :modulename

                 JOIN {course_modules} cm

                   ON cm.instance = customcert.id

                  AND cm.module = m.id

                WHERE cm.id $insql";

        $params = array_merge($inparams, ['modulename' => 'customcert']);

        return $DB->get_records_sql_menu($sql, $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);

        }

    }

}