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_enrol.

 *

 * @package    core_enrol

 * @copyright  2018 Carlos Escobedo <carlos@moodle.com>

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

 */

namespace core_enrol\privacy;

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

use core_privacy\local\metadata\collection;

use core_privacy\local\request\approved_contextlist;

use core_privacy\local\request\context;

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;

/**

 * Privacy Subsystem for core_enrol implementing metadata and plugin providers.

 *

 * @copyright  2018 Carlos Escobedo <carlos@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 {

    /**

     * Returns meta data about this system.

     *

     * @param   collection $collection The initialised collection to add items to.

     * @return  collection     A listing of user data stored through this system.

     */

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

        $collection->add_database_table(

            'user_enrolments',

            [

                'status' => 'privacy:metadata:user_enrolments:status',

                'enrolid' => 'privacy:metadata:user_enrolments:enrolid',

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

                'timestart' => 'privacy:metadata:user_enrolments:timestart',

                'timeend' => 'privacy:metadata:user_enrolments:timeend',

                'modifierid' => 'privacy:metadata:user_enrolments:modifierid',

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

                'timemodified' => 'privacy:metadata:user_enrolments:timemodified'

            ],

            'privacy:metadata:user_enrolments:tableexplanation'

        );

        return $collection;

    }

    /**

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

     *

     * @param   int $userid The user to search.

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

     */

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

        $sql = "SELECT ctx.id

                  FROM {user_enrolments} ue

                  JOIN {enrol} e

                    ON e.id = ue.enrolid

                   AND ue.userid = :userid

                  JOIN {context} ctx

                    ON ctx.instanceid = e.courseid

                   AND ctx.contextlevel = :contextlevel";

        $params = [

            'contextlevel' => CONTEXT_COURSE,

            'userid'       => $userid

        ];

        $contextlist = new contextlist();

        $contextlist->add_from_sql($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) {

            return;

        }

        $sql = "SELECT ue.userid as userid

                  FROM {user_enrolments} ue

                  JOIN {enrol} e ON e.id = ue.enrolid

                 WHERE e.courseid = ?";

        $params = [$context->instanceid];

        $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;

        }

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

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

        $params = [

            'contextlevel' => CONTEXT_COURSE,

            'userid' => $userid

         ];

        $params += $inparams;

        $sql = "SELECT ue.id,

                       ue.status,

                       ue.timestart,

                       ue.timeend,

                       ue.timecreated,

                       ue.timemodified,

                       e.enrol,

                       ctx.id as contextid

                  FROM {user_enrolments} ue

                  JOIN {enrol} e

                    ON e.id = ue.enrolid

                   AND ue.userid = :userid

                  JOIN {context} ctx

                    ON ctx.instanceid = e.courseid

                   AND ctx.contextlevel = :contextlevel

                 WHERE ctx.id $insql

                 ORDER BY ctx.id, e.enrol";

        $data = [];

        $lastcontextid = null;

        $lastenrol = null;

        $path = [get_string('privacy:metadata:user_enrolments', 'core_enrol')];

        $flush = function($lastcontextid, $lastenrol, $data) use ($path) {

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

            writer::with_context($context)->export_related_data(

                $path,

                $lastenrol,

                (object)$data

            );

        };

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

        foreach ($userenrolments as $userenrolment) {

            if (($lastcontextid && $lastcontextid != $userenrolment->contextid) ||

                    ($lastenrol && $lastenrol != $userenrolment->enrol)) {

                $flush($lastcontextid, $lastenrol, $data);

                $data = [];

            }

            $data[] = (object) [

                'status' => $userenrolment->status,

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

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

                'timestart' => transform::datetime($userenrolment->timestart),

                'timeend' => transform::datetime($userenrolment->timeend)

            ];

            $lastcontextid = $userenrolment->contextid;

            $lastenrol = $userenrolment->enrol;

        }

        if (!empty($data)) {

            $flush($lastcontextid, $lastenrol, $data);

        }

        $userenrolments->close();

    }

    /**

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

     *

     * @param   \context $context The specific context to delete data for.

     */

    public static function delete_data_for_all_users_in_context(\context $context) {

        global $DB;

        // Sanity check that context is at the User context level.

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

            $sql = "SELECT ue.id

                      FROM {user_enrolments} ue

                      JOIN {enrol} e ON e.id = ue.enrolid

                     WHERE e.courseid = :courseid";

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

            $enrolsids = $DB->get_fieldset_sql($sql, $params);

            if (!empty($enrolsids)) {

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

                static::delete_user_data($insql, $inparams);

            }

        }

    }

    /**

     * 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) {

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

            $sql = "SELECT ue.id

                      FROM {user_enrolments} ue

                      JOIN {enrol} e ON e.id = ue.enrolid

                     WHERE e.courseid = :courseid

                           AND ue.userid {$usersql}";

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

            $enrolsids = $DB->get_fieldset_sql($sql, $params);

            if (!empty($enrolsids)) {

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

                static::delete_user_data($insql, $inparams);

            }

        }

    }

    /**

     * 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;

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

            return;

        }

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

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

        $params = [

            'contextlevel' => CONTEXT_COURSE,

            'userid' => $userid

         ];

        $params += $inparams;

        $sql = "SELECT ue.id

                  FROM {user_enrolments} ue

                  JOIN {enrol} e

                    ON e.id = ue.enrolid

                   AND ue.userid = :userid

                  JOIN {context} ctx

                    ON ctx.instanceid = e.courseid

                   AND ctx.contextlevel = :contextlevel

                 WHERE ctx.id $insql";

        $enrolsids = $DB->get_fieldset_sql($sql, $params);

        if (!empty($enrolsids)) {

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

            static::delete_user_data($insql, $inparams);

        }

    }

    /**

     * Delete data from $tablename with the IDs returned by $sql query.

     *

     * @param  string $sql    SQL query for getting the IDs of the uer enrolments entries to delete.

     * @param  array  $params SQL params for the query.

     */

    protected static function delete_user_data(string $sql, array $params) {

        global $DB;

        $DB->delete_records_select('user_enrolments', "id $sql", $params);

    }

    /**

     * Get the subcontext for export.

     *

     * @param array $subcontext Any additional subcontext to use.

     * @return array The array containing the full subcontext, i.e. [enrolments, subcontext]

     */

    public static function get_subcontext(array $subcontext) {

        return array_merge(

            [get_string('privacy:metadata:user_enrolments', 'core_enrol')],

            $subcontext

        );

    }

}