moodle/lib/classes/context/course.php
2023-03-31 23:09:39 +02:00

299 lines
10 KiB
PHP

<?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;
/**
* Course 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 course extends context {
/** @var int numeric context level value matching legacy CONTEXT_COURSE */
public const LEVEL = 50;
/**
* Please use \core\context\course::instance($courseid) if you need the instance of context.
* Alternatively if you know only the context id use \core\context::instance_by_id($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\course constructor.');
}
}
/**
* Returns short context name.
*
* @since Moodle 4.2
*
* @return string
*/
public static function get_short_name(): string {
return 'course';
}
/**
* Returns human readable context level name.
*
* @return string the human readable context level name.
*/
public static function get_level_name() {
return get_string('course');
}
/**
* Returns human readable context identifier.
*
* @param boolean $withprefix whether to prefix the name of the context with Course
* @param boolean $short whether to use the short name of the thing.
* @param bool $escape Whether the returned category name is to be HTML escaped or not.
* @return string the human readable context name.
*/
public function get_context_name($withprefix = true, $short = false, $escape = true) {
global $DB;
$name = '';
if ($this->_instanceid == SITEID) {
$name = get_string('frontpage', 'admin');
} else {
if ($course = $DB->get_record('course', array('id' => $this->_instanceid))) {
if ($withprefix) {
$name = get_string('course').': ';
}
if ($short) {
if (!$escape) {
$name .= format_string($course->shortname, true, array('context' => $this, 'escape' => false));
} else {
$name .= format_string($course->shortname, true, array('context' => $this));
}
} else {
if (!$escape) {
$name .= format_string(get_course_display_name_for_list($course), true, array('context' => $this,
'escape' => false));
} else {
$name .= format_string(get_course_display_name_for_list($course), true, array('context' => $this));
}
}
}
}
return $name;
}
/**
* Returns the most relevant URL for this context.
*
* @return moodle_url
*/
public function get_url() {
if ($this->_instanceid != SITEID) {
return new moodle_url('/course/view.php', array('id' => $this->_instanceid));
}
return new moodle_url('/');
}
/**
* Returns context instance database name.
*
* @return string|null table name for all levels except system.
*/
protected static function get_instance_table(): ?string {
return 'course';
}
/**
* 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 ['shortname'];
}
/**
* Returns list of all role archetypes that are compatible
* with role assignments in context level.
* @since Moodle 4.2
*
* @return int[]
*/
protected static function get_compatible_role_archetypes(): array {
return ['manager', 'editingteacher', 'teacher', 'student'];
}
/**
* Returns list of all possible parent context levels.
* @since Moodle 4.2
*
* @return int[]
*/
public static function get_possible_parent_levels(): array {
return [coursecat::LEVEL];
}
/**
* Returns array of relevant context capability records.
*
* @param string $sort
* @return array
*/
public function get_capabilities(string $sort = self::DEFAULT_CAPABILITY_SORT) {
global $DB;
$levels = \core\context_helper::get_child_levels(self::LEVEL);
$levels[] = self::LEVEL;
return $DB->get_records_list('capabilities', 'contextlevel', $levels, $sort);
}
/**
* Is this context part of any course? If yes return course context.
*
* @param bool $strict true means throw exception if not found, false means return false if not found
* @return course context of the enclosing course, null if not found or exception
*/
public function get_course_context($strict = true) {
return $this;
}
/**
* Returns course context instance.
*
* @param int $courseid id from {course} table
* @param int $strictness
* @return course|false context instance
*/
public static function instance($courseid, $strictness = MUST_EXIST) {
global $DB;
if ($context = context::cache_get(self::LEVEL, $courseid)) {
return $context;
}
if (!$record = $DB->get_record('context', array('contextlevel' => self::LEVEL, 'instanceid' => $courseid))) {
if ($course = $DB->get_record('course', array('id' => $courseid), 'id,category', $strictness)) {
if ($course->category) {
$parentcontext = coursecat::instance($course->category);
$record = context::insert_context_record(self::LEVEL, $course->id, $parentcontext->path);
} else {
$record = context::insert_context_record(self::LEVEL, $course->id, '/'.SYSCONTEXTID, 0);
}
}
}
if ($record) {
$context = new course($record);
context::cache_add($context);
return $context;
}
return false;
}
/**
* Create missing context instances at course context level
*/
protected static function create_level_instances() {
global $DB;
$sql = "SELECT ".self::LEVEL.", c.id
FROM {course} c
WHERE NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE c.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 {course} co ON c.instanceid = co.id
WHERE co.id IS NULL AND c.contextlevel = ".self::LEVEL."
";
return $sql;
}
/**
* Rebuild context paths and depths at course context level.
*
* @param bool $force
*/
protected static function build_paths($force) {
global $DB;
if ($force || $DB->record_exists_select('context', "contextlevel = ".self::LEVEL." AND (depth = 0 OR path IS NULL)")) {
if ($force) {
$ctxemptyclause = $emptyclause = '';
} else {
$ctxemptyclause = "AND (ctx.path IS NULL OR ctx.depth = 0)";
$emptyclause = "AND ({context}.path IS NULL OR {context}.depth = 0)";
}
$base = '/'.SYSCONTEXTID;
// Standard frontpage.
$sql = "UPDATE {context}
SET depth = 2,
path = ".$DB->sql_concat("'$base/'", 'id')."
WHERE contextlevel = ".self::LEVEL."
AND EXISTS (SELECT 'x'
FROM {course} c
WHERE c.id = {context}.instanceid AND c.category = 0)
$emptyclause";
$DB->execute($sql);
// Standard courses.
$sql = "INSERT INTO {context_temp} (id, path, depth, locked)
SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", pctx.depth+1, ctx.locked
FROM {context} ctx
JOIN {course} c ON (c.id = ctx.instanceid AND ctx.contextlevel = ".self::LEVEL." AND c.category <> 0)
JOIN {context} pctx ON (pctx.instanceid = c.category AND pctx.contextlevel = ".coursecat::LEVEL.")
WHERE pctx.path IS NOT NULL AND pctx.depth > 0
$ctxemptyclause";
$trans = $DB->start_delegated_transaction();
$DB->delete_records('context_temp');
$DB->execute($sql);
context::merge_context_temp_table();
$DB->delete_records('context_temp');
$trans->allow_commit();
}
}
}