<?php
// This file is part of Moodle - https://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 <https://www.gnu.org/licenses/>.
namespace core\context;
use core\context;
use stdClass;
use coding_exception, moodle_url;
/**
* User context class
*
* @package core_access
* @category access
* @copyright Petr Skoda
* @license https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 4.2
*/
class user extends context {
/** @var int numeric context level value matching legacy CONTEXT_USER */
public const LEVEL = 30;
/**
* Please use \core\context\user::instance($userid) if you need the instance of context.
* Alternatively if you know only the context id use \core\context::instance_by_id($contextid)
*
* @param stdClass $record
*/
protected function __construct(stdClass $record) {
parent::__construct($record);
if ($record->contextlevel != self::LEVEL) {
throw new coding_exception('Invalid $record->contextlevel in core\context\user constructor.');
}
}
/**
* Returns short context name.
*
* @since Moodle 4.2
*
* @return string
*/
public static function get_short_name(): string {
return 'user';
}
/**
* Returns human readable context level name.
*
* @return string the human readable context level name.
*/
public static function get_level_name() {
return get_string('user');
}
/**
* Returns human readable context identifier.
*
* @param boolean $withprefix whether to prefix the name of the context with User
* @param boolean $short does not apply to user context
* @param boolean $escape does not apply to user context
* @return string the human readable context name.
*/
public function get_context_name($withprefix = true, $short = false, $escape = true) {
global $DB;
$name = '';
if ($user = $DB->get_record('user', array('id' => $this->_instanceid, 'deleted' => 0))) {
if ($withprefix) {
$name = get_string('user').': ';
}
$name .= fullname($user);
}
return $name;
}
/**
* Returns the most relevant URL for this context.
*
* @return moodle_url
*/
public function get_url() {
global $COURSE;
if ($COURSE->id == SITEID) {
$url = new moodle_url('/user/profile.php', array('id' => $this->_instanceid));
} else {
$url = new moodle_url('/user/view.php', array('id' => $this->_instanceid, 'courseid' => $COURSE->id));
}
return $url;
}
/**
* Returns list of all possible parent context levels.
* @since Moodle 4.2
*
* @return int[]
*/
public static function get_possible_parent_levels(): array {
return [system::LEVEL];
}
/**
* Returns context instance database name.
*
* @return string|null table name for all levels except system.
*/
protected static function get_instance_table(): ?string {
return 'user';
}
/**
* Returns list of columns that can be used from behat
* to look up context by reference.
*
* @return array list of column names from instance table
*/
protected static function get_behat_reference_columns(): array {
return ['username'];
}
/**
* Returns array of relevant context capability records.
*
* @param string $sort
* @return array
*/
public function get_capabilities(string $sort = self::DEFAULT_CAPABILITY_SORT) {
global $DB;
$extracaps = array('moodle/grade:viewall');
list($extra, $params) = $DB->get_in_or_equal($extracaps, SQL_PARAMS_NAMED, 'cap');
return $DB->get_records_select('capabilities', "contextlevel = :level OR name {$extra}",
$params + ['level' => self::LEVEL], $sort);
}
/**
* Returns user context instance.
*
* @param int $userid id from {user} table
* @param int $strictness
* @return user|false context instance
*/
public static function instance($userid, $strictness = MUST_EXIST) {
global $DB;
if ($context = context::cache_get(self::LEVEL, $userid)) {
return $context;
}
if (!$record = $DB->get_record('context', array('contextlevel' => self::LEVEL, 'instanceid' => $userid))) {
if ($user = $DB->get_record('user', array('id' => $userid, 'deleted' => 0), 'id', $strictness)) {
$record = context::insert_context_record(self::LEVEL, $user->id, '/'.SYSCONTEXTID, 0);
}
}
if ($record) {
$context = new user($record);
context::cache_add($context);
return $context;
}
return false;
}
/**
* Create missing context instances at user context level
*/
protected static function create_level_instances() {
global $DB;
$sql = "SELECT " . self::LEVEL . ", u.id
FROM {user} u
WHERE u.deleted = 0
AND NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE u.id = cx.instanceid AND cx.contextlevel=" . self::LEVEL . ")";
$contextdata = $DB->get_recordset_sql($sql);
foreach ($contextdata as $context) {
context::insert_context_record(self::LEVEL, $context->id, null);
}
$contextdata->close();
}
/**
* Returns sql necessary for purging of stale context instances.
*
* @return string cleanup SQL
*/
protected static function get_cleanup_sql() {
$sql = "
SELECT c.*
FROM {context} c
LEFT OUTER JOIN {user} u ON (c.instanceid = u.id AND u.deleted = 0)
WHERE u.id IS NULL AND c.contextlevel = " . self::LEVEL . "
";
return $sql;
}
/**
* Rebuild context paths and depths at user context level.
*
* @param bool $force
*/
protected static function build_paths($force) {
global $DB;
// First update normal users.
$path = $DB->sql_concat('?', 'id');
$pathstart = '/' . SYSCONTEXTID . '/';
$params = array($pathstart);
if ($force) {
$where = "depth <> 2 OR path IS NULL OR path <> ({$path})";
$params[] = $pathstart;
} else {
$where = "depth = 0 OR path IS NULL";
}
$sql = "UPDATE {context}
SET depth = 2,
path = {$path}
WHERE contextlevel = " . self::LEVEL . "
AND ($where)";
$DB->execute($sql, $params);
}
}