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modinfolib.php
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modinfolib.php
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<?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/>.
/**
* modinfolib.php - Functions/classes relating to cached information about module instances on
* a course.
* @package core
* @subpackage lib
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @author sam marshall
*/
// Maximum number of modinfo items to keep in memory cache. Do not increase this to a large
// number because:
// a) modinfo can be big (megabyte range) for some courses
// b) performance of cache will deteriorate if there are very many items in it
if (!defined('MAX_MODINFO_CACHE_SIZE')) {
define('MAX_MODINFO_CACHE_SIZE', 10);
}
/**
* Information about a course that is cached in the course table 'modinfo' field (and then in
* memory) in order to reduce the need for other database queries.
*
* This includes information about the course-modules and the sections on the course. It can also
* include dynamic data that has been updated for the current user.
*
* Use {@link get_fast_modinfo()} to retrieve the instance of the object for particular course
* and particular user.
*
* @property-read int $courseid Course ID
* @property-read int $userid User ID
* @property-read array $sections Array from section number (e.g. 0) to array of course-module IDs in that
* section; this only includes sections that contain at least one course-module
* @property-read cm_info[] $cms Array from course-module instance to cm_info object within this course, in
* order of appearance
* @property-read cm_info[][] $instances Array from string (modname) => int (instance id) => cm_info object
* @property-read array $groups Groups that the current user belongs to. Calculated on the first request.
* Is an array of grouping id => array of group id => group id. Includes grouping id 0 for 'all groups'
*/
class course_modinfo {
/**
* List of fields from DB table 'course' that are cached in MUC and are always present in course_modinfo::$course
* @var array
*/
public static $cachedfields = array('shortname', 'fullname', 'format',
'enablecompletion', 'groupmode', 'groupmodeforce', 'cacherev');
/**
* For convenience we store the course object here as it is needed in other parts of code
* @var stdClass
*/
private $course;
/**
* Array of section data from cache
* @var section_info[]
*/
private $sectioninfo;
/**
* User ID
* @var int
*/
private $userid;
/**
* Array from int (section num, e.g. 0) => array of int (course-module id); this list only
* includes sections that actually contain at least one course-module
* @var array
*/
private $sections;
/**
* Array from int (cm id) => cm_info object
* @var cm_info[]
*/
private $cms;
/**
* Array from string (modname) => int (instance id) => cm_info object
* @var cm_info[][]
*/
private $instances;
/**
* Groups that the current user belongs to. This value is usually not available (set to null)
* unless the course has activities set to groupmembersonly. When set, it is an array of
* grouping id => array of group id => group id. Includes grouping id 0 for 'all groups'.
* @var int[][]
*/
private $groups;
/**
* List of class read-only properties and their getter methods.
* Used by magic functions __get(), __isset(), __empty()
* @var array
*/
private static $standardproperties = array(
'courseid' => 'get_course_id',
'userid' => 'get_user_id',
'sections' => 'get_sections',
'cms' => 'get_cms',
'instances' => 'get_instances',
'groups' => 'get_groups_all',
);
/**
* Magic method getter
*
* @param string $name
* @return mixed
*/
public function __get($name) {
if (isset(self::$standardproperties[$name])) {
$method = self::$standardproperties[$name];
return $this->$method();
} else {
debugging('Invalid course_modinfo property accessed: '.$name);
return null;
}
}
/**
* Magic method for function isset()
*
* @param string $name
* @return bool
*/
public function __isset($name) {
if (isset(self::$standardproperties[$name])) {
$value = $this->__get($name);
return isset($value);
}
return false;
}
/**
* Magic method for function empty()
*
* @param string $name
* @return bool
*/
public function __empty($name) {
if (isset(self::$standardproperties[$name])) {
$value = $this->__get($name);
return empty($value);
}
return true;
}
/**
* Magic method setter
*
* Will display the developer warning when trying to set/overwrite existing property.
*
* @param string $name
* @param mixed $value
*/
public function __set($name, $value) {
debugging("It is not allowed to set the property course_modinfo::\${$name}", DEBUG_DEVELOPER);
}
/**
* Returns course object that was used in the first {@link get_fast_modinfo()} call.
*
* It may not contain all fields from DB table {course} but always has at least the following:
* id,shortname,fullname,format,enablecompletion,groupmode,groupmodeforce,cacherev
*
* @return stdClass
*/
public function get_course() {
return $this->course;
}
/**
* @return int Course ID
*/
public function get_course_id() {
return $this->course->id;
}
/**
* @return int User ID
*/
public function get_user_id() {
return $this->userid;
}
/**
* @return array Array from section number (e.g. 0) to array of course-module IDs in that
* section; this only includes sections that contain at least one course-module
*/
public function get_sections() {
return $this->sections;
}
/**
* @return cm_info[] Array from course-module instance to cm_info object within this course, in
* order of appearance
*/
public function get_cms() {
return $this->cms;
}
/**
* Obtains a single course-module object (for a course-module that is on this course).
* @param int $cmid Course-module ID
* @return cm_info Information about that course-module
* @throws moodle_exception If the course-module does not exist
*/
public function get_cm($cmid) {
if (empty($this->cms[$cmid])) {
throw new moodle_exception('invalidcoursemodule', 'error');
}
return $this->cms[$cmid];
}
/**
* Obtains all module instances on this course.
* @return cm_info[][] Array from module name => array from instance id => cm_info
*/
public function get_instances() {
return $this->instances;
}
/**
* Returns array of localised human-readable module names used in this course
*
* @param bool $plural if true returns the plural form of modules names
* @return array
*/
public function get_used_module_names($plural = false) {
$modnames = get_module_types_names($plural);
$modnamesused = array();
foreach ($this->get_cms() as $cmid => $mod) {
if (isset($modnames[$mod->modname]) && $mod->uservisible) {
$modnamesused[$mod->modname] = $modnames[$mod->modname];
}
}
core_collator::asort($modnamesused);
return $modnamesused;
}
/**
* Obtains all instances of a particular module on this course.
* @param $modname Name of module (not full frankenstyle) e.g. 'label'
* @return cm_info[] Array from instance id => cm_info for modules on this course; empty if none
*/
public function get_instances_of($modname) {
if (empty($this->instances[$modname])) {
return array();
}
return $this->instances[$modname];
}
/**
* Groups that the current user belongs to organised by grouping id. Calculated on the first request.
* @return int[][] array of grouping id => array of group id => group id. Includes grouping id 0 for 'all groups'
*/
private function get_groups_all() {
if (is_null($this->groups)) {
// NOTE: Performance could be improved here. The system caches user groups
// in $USER->groupmember[$courseid] => array of groupid=>groupid. Unfortunately this
// structure does not include grouping information. It probably could be changed to
// do so, without a significant performance hit on login, thus saving this one query
// each request.
$this->groups = groups_get_user_groups($this->course->id, $this->userid);
}
return $this->groups;
}
/**
* Returns groups that the current user belongs to on the course. Note: If not already
* available, this may make a database query.
* @param int $groupingid Grouping ID or 0 (default) for all groups
* @return int[] Array of int (group id) => int (same group id again); empty array if none
*/
public function get_groups($groupingid = 0) {
$allgroups = $this->get_groups_all();
if (!isset($allgroups[$groupingid])) {
return array();
}
return $allgroups[$groupingid];
}
/**
* Gets all sections as array from section number => data about section.
* @return section_info[] Array of section_info objects organised by section number
*/
public function get_section_info_all() {
return $this->sectioninfo;
}
/**
* Gets data about specific numbered section.
* @param int $sectionnumber Number (not id) of section
* @param int $strictness Use MUST_EXIST to throw exception if it doesn't
* @return section_info Information for numbered section or null if not found
*/
public function get_section_info($sectionnumber, $strictness = IGNORE_MISSING) {
if (!array_key_exists($sectionnumber, $this->sectioninfo)) {
if ($strictness === MUST_EXIST) {
throw new moodle_exception('sectionnotexist');
} else {
return null;
}
}
return $this->sectioninfo[$sectionnumber];
}
/**
* Static cache for generated course_modinfo instances
*
* @see course_modinfo::instance()
* @see course_modinfo::clear_instance_cache()
* @var course_modinfo[]
*/
protected static $instancecache = array();
/**
* Timestamps (microtime) when the course_modinfo instances were last accessed
*
* It is used to remove the least recent accessed instances when static cache is full
*
* @var float[]
*/
protected static $cacheaccessed = array();
/**
* Clears the cache used in course_modinfo::instance()
*
* Used in {@link get_fast_modinfo()} when called with argument $reset = true
* and in {@link rebuild_course_cache()}
*
* @param null|int|stdClass $courseorid if specified removes only cached value for this course
*/
public static function clear_instance_cache($courseorid = null) {
if (empty($courseorid)) {
self::$instancecache = array();
self::$cacheaccessed = array();
return;
}
if (is_object($courseorid)) {
$courseorid = $courseorid->id;
}
if (isset(self::$instancecache[$courseorid])) {
// Unsetting static variable in PHP is peculiar, it removes the reference,
// but data remain in memory. Prior to unsetting, the varable needs to be
// set to empty to remove its remains from memory.
self::$instancecache[$courseorid] = '';
unset(self::$instancecache[$courseorid]);
unset(self::$cacheaccessed[$courseorid]);
}
}
/**
* Returns the instance of course_modinfo for the specified course and specified user
*
* This function uses static cache for the retrieved instances. The cache
* size is limited by MAX_MODINFO_CACHE_SIZE. If instance is not found in
* the static cache or it was created for another user or the cacherev validation
* failed - a new instance is constructed and returned.
*
* Used in {@link get_fast_modinfo()}
*
* @param int|stdClass $courseorid object from DB table 'course' (must have field 'id'
* and recommended to have field 'cacherev') or just a course id
* @param int $userid User id to populate 'availble' and 'uservisible' attributes of modules and sections.
* Set to 0 for current user (default). Set to -1 to avoid calculation of dynamic user-depended data.
* @return course_modinfo
*/
public static function instance($courseorid, $userid = 0) {
global $USER;
if (is_object($courseorid)) {
$course = $courseorid;
} else {
$course = (object)array('id' => $courseorid);
}
if (empty($userid)) {
$userid = $USER->id;
}
if (!empty(self::$instancecache[$course->id])) {
if (self::$instancecache[$course->id]->userid == $userid &&
(!isset($course->cacherev) ||
$course->cacherev == self::$instancecache[$course->id]->get_course()->cacherev)) {
// This course's modinfo for the same user was recently retrieved, return cached.
self::$cacheaccessed[$course->id] = microtime(true);
return self::$instancecache[$course->id];
} else {
// Prevent potential reference problems when switching users.
self::clear_instance_cache($course->id);
}
}
$modinfo = new course_modinfo($course, $userid);
// We have a limit of MAX_MODINFO_CACHE_SIZE entries to store in static variable.
if (count(self::$instancecache) >= MAX_MODINFO_CACHE_SIZE) {
// Find the course that was the least recently accessed.
asort(self::$cacheaccessed, SORT_NUMERIC);
$courseidtoremove = key(array_reverse(self::$cacheaccessed, true));
self::clear_instance_cache($courseidtoremove);
}
// Add modinfo to the static cache.
self::$instancecache[$course->id] = $modinfo;
self::$cacheaccessed[$course->id] = microtime(true);
return $modinfo;
}
/**
* Constructs based on course.
* Note: This constructor should not usually be called directly.
* Use get_fast_modinfo($course) instead as this maintains a cache.
* @param stdClass $course course object, only property id is required.
* @param int $userid User ID
* @throws moodle_exception if course is not found
*/
public function __construct($course, $userid) {
global $CFG, $COURSE, $SITE, $DB;
if (!isset($course->cacherev)) {
// We require presence of property cacherev to validate the course cache.
// No need to clone the $COURSE or $SITE object here because we clone it below anyway.
$course = get_course($course->id, false);
}
$cachecoursemodinfo = cache::make('core', 'coursemodinfo');
// Retrieve modinfo from cache. If not present or cacherev mismatches, call rebuild and retrieve again.
$coursemodinfo = $cachecoursemodinfo->get($course->id);
if ($coursemodinfo === false || ($course->cacherev != $coursemodinfo->cacherev)) {
$coursemodinfo = self::build_course_cache($course);
}
// Set initial values
$this->userid = $userid;
$this->sections = array();
$this->cms = array();
$this->instances = array();
$this->groups = null;
// If we haven't already preloaded contexts for the course, do it now
// Modules are also cached here as long as it's the first time this course has been preloaded.
context_helper::preload_course($course->id);
// Quick integrity check: as a result of race conditions modinfo may not be regenerated after the change.
// It is especially dangerous if modinfo contains the deleted course module, as it results in fatal error.
// We can check it very cheap by validating the existence of module context.
if ($course->id == $COURSE->id || $course->id == $SITE->id) {
// Only verify current course (or frontpage) as pages with many courses may not have module contexts cached.
// (Uncached modules will result in a very slow verification).
foreach ($coursemodinfo->modinfo as $mod) {
if (!context_module::instance($mod->cm, IGNORE_MISSING)) {
debugging('Course cache integrity check failed: course module with id '. $mod->cm.
' does not have context. Rebuilding cache for course '. $course->id);
// Re-request the course record from DB as well, don't use get_course() here.
$course = $DB->get_record('course', array('id' => $course->id), '*', MUST_EXIST);
$coursemodinfo = self::build_course_cache($course);
break;
}
}
}
// Overwrite unset fields in $course object with cached values, store the course object.
$this->course = fullclone($course);
foreach ($coursemodinfo as $key => $value) {
if ($key !== 'modinfo' && $key !== 'sectioncache' &&
(!isset($this->course->$key) || $key === 'cacherev')) {
$this->course->$key = $value;
}
}
// Loop through each piece of module data, constructing it
static $modexists = array();
foreach ($coursemodinfo->modinfo as $mod) {
if (empty($mod->name)) {
// something is wrong here
continue;
}
// Skip modules which don't exist
if (!array_key_exists($mod->mod, $modexists)) {
$modexists[$mod->mod] = file_exists("$CFG->dirroot/mod/$mod->mod/lib.php");
}
if (!$modexists[$mod->mod]) {
continue;
}
// Construct info for this module
$cm = new cm_info($this, null, $mod, null);
// Store module in instances and cms array
if (!isset($this->instances[$cm->modname])) {
$this->instances[$cm->modname] = array();
}
$this->instances[$cm->modname][$cm->instance] = $cm;
$this->cms[$cm->id] = $cm;
// Reconstruct sections. This works because modules are stored in order
if (!isset($this->sections[$cm->sectionnum])) {
$this->sections[$cm->sectionnum] = array();
}
$this->sections[$cm->sectionnum][] = $cm->id;
}
// Expand section objects
$this->sectioninfo = array();
foreach ($coursemodinfo->sectioncache as $number => $data) {
$this->sectioninfo[$number] = new section_info($data, $number, null, null,
$this, null);
}
}
/**
* Builds a list of information about sections on a course to be stored in
* the course cache. (Does not include information that is already cached
* in some other way.)
*
* This function will be removed in 2.7
*
* @deprecated since 2.6
* @param int $courseid Course ID
* @return array Information about sections, indexed by section number (not id)
*/
public static function build_section_cache($courseid) {
global $DB;
debugging('Function course_modinfo::build_section_cache() is deprecated. It can only be used internally to build course cache.');
$course = $DB->get_record('course', array('id' => $course->id),
array_merge(array('id'), self::$cachedfields), MUST_EXIST);
return self::build_course_section_cache($course);
}
/**
* Builds a list of information about sections on a course to be stored in
* the course cache. (Does not include information that is already cached
* in some other way.)
*
* @param stdClass $course Course object (must contain fields
* @return array Information about sections, indexed by section number (not id)
*/
protected static function build_course_section_cache($course) {
global $DB;
// Get section data
$sections = $DB->get_records('course_sections', array('course' => $course->id), 'section',
'section, id, course, name, summary, summaryformat, sequence, visible, ' .
'availablefrom, availableuntil, showavailability, groupingid');
$compressedsections = array();
$formatoptionsdef = course_get_format($course)->section_format_options();
// Remove unnecessary data and add availability
foreach ($sections as $number => $section) {
// Add cached options from course format to $section object
foreach ($formatoptionsdef as $key => $option) {
if (!empty($option['cache'])) {
$formatoptions = course_get_format($course)->get_format_options($section);
if (!array_key_exists('cachedefault', $option) || $option['cachedefault'] !== $formatoptions[$key]) {
$section->$key = $formatoptions[$key];
}
}
}
// Clone just in case it is reused elsewhere
$compressedsections[$number] = clone($section);
section_info::convert_for_section_cache($compressedsections[$number]);
}
return $compressedsections;
}
/**
* Builds and stores in MUC object containing information about course
* modules and sections together with cached fields from table course.
*
* @param stdClass $course object from DB table course. Must have property 'id'
* but preferably should have all cached fields.
* @return stdClass object with all cached keys of the course plus fields modinfo and sectioncache.
* The same object is stored in MUC
* @throws moodle_exception if course is not found (if $course object misses some of the
* necessary fields it is re-requested from database)
*/
public static function build_course_cache($course) {
global $DB, $CFG;
require_once("$CFG->dirroot/course/lib.php");
if (empty($course->id)) {
throw new coding_exception('Object $course is missing required property \id\'');
}
// Ensure object has all necessary fields.
foreach (self::$cachedfields as $key) {
if (!isset($course->$key)) {
$course = $DB->get_record('course', array('id' => $course->id),
implode(',', array_merge(array('id'), self::$cachedfields)), MUST_EXIST);
break;
}
}
// Retrieve all information about activities and sections.
// This may take time on large courses and it is possible that another user modifies the same course during this process.
// Field cacherev stored in both DB and cache will ensure that cached data matches the current course state.
$coursemodinfo = new stdClass();
$coursemodinfo->modinfo = get_array_of_activities($course->id);
$coursemodinfo->sectioncache = self::build_course_section_cache($course);
foreach (self::$cachedfields as $key) {
$coursemodinfo->$key = $course->$key;
}
// Set the accumulated activities and sections information in cache, together with cacherev.
$cachecoursemodinfo = cache::make('core', 'coursemodinfo');
$cachecoursemodinfo->set($course->id, $coursemodinfo);
return $coursemodinfo;
}
}
/**
* Data about a single module on a course. This contains most of the fields in the course_modules
* table, plus additional data when required.
*
* The object can be accessed by core or any plugin (i.e. course format, block, filter, etc.) as
* get_fast_modinfo($courseorid)->cms[$coursemoduleid]
* or
* get_fast_modinfo($courseorid)->instances[$moduletype][$instanceid]
*
* There are three stages when activity module can add/modify data in this object:
*
* <b>Stage 1 - during building the cache.</b>
* Allows to add to the course cache static user-independent information about the module.
* Modules should try to include only absolutely necessary information that may be required
* when displaying course view page. The information is stored in application-level cache
* and reset when {@link rebuild_course_cache()} is called or cache is purged by admin.
*
* Modules can implement callback XXX_get_coursemodule_info() returning instance of object
* {@link cached_cm_info}
*
* <b>Stage 2 - dynamic data.</b>
* Dynamic data is user-dependend, it is stored in request-level cache. To reset this cache
* {@link get_fast_modinfo()} with $reset argument may be called.
*
* Dynamic data is obtained when any of the following properties/methods is requested:
* - {@link cm_info::$url}
* - {@link cm_info::$name}
* - {@link cm_info::$onclick}
* - {@link cm_info::get_icon_url()}
* - {@link cm_info::$uservisible}
* - {@link cm_info::$available}
* - {@link cm_info::$showavailability}
* - {@link cm_info::$availableinfo}
* - plus any of the properties listed in Stage 3.
*
* Modules can implement callback <b>XXX_cm_info_dynamic()</b> and inside this callback they
* are allowed to use any of the following set methods:
* - {@link cm_info::set_available()}
* - {@link cm_info::set_name()}
* - {@link cm_info::set_no_view_link()}
* - {@link cm_info::set_user_visible()}
* - {@link cm_info::set_on_click()}
* - {@link cm_info::set_icon_url()}
* Any methods affecting view elements can also be set in this callback.
*
* <b>Stage 3 (view data).</b>
* Also user-dependend data stored in request-level cache. Second stage is created
* because populating the view data can be expensive as it may access much more
* Moodle APIs such as filters, user information, output renderers and we
* don't want to request it until necessary.
* View data is obtained when any of the following properties/methods is requested:
* - {@link cm_info::$afterediticons}
* - {@link cm_info::$content}
* - {@link cm_info::get_formatted_content()}
* - {@link cm_info::$extraclasses}
* - {@link cm_info::$afterlink}
*
* Modules can implement callback <b>XXX_cm_info_view()</b> and inside this callback they
* are allowed to use any of the following set methods:
* - {@link cm_info::set_after_edit_icons()}
* - {@link cm_info::set_after_link()}
* - {@link cm_info::set_content()}
* - {@link cm_info::set_extra_classes()}
*
* @property-read int $id Course-module ID - from course_modules table
* @property-read int $instance Module instance (ID within module table) - from course_modules table
* @property-read int $course Course ID - from course_modules table
* @property-read string $idnumber 'ID number' from course-modules table (arbitrary text set by user) - from
* course_modules table
* @property-read int $added Time that this course-module was added (unix time) - from course_modules table
* @property-read int $visible Visible setting (0 or 1; if this is 0, students cannot see/access the activity) - from
* course_modules table
* @property-read int $visibleold Old visible setting (if the entire section is hidden, the previous value for
* visible is stored in this field) - from course_modules table
* @property-read int $groupmode Group mode (one of the constants NOGROUPS, SEPARATEGROUPS, or VISIBLEGROUPS) - from
* course_modules table. Use {@link cm_info::$effectivegroupmode} to find the actual group mode that may be forced by course.
* @property-read int $groupingid Grouping ID (0 = all groupings)
* @property-read int $groupmembersonly Group members only (if set to 1, only members of a suitable group see this link on the
* course page; 0 = everyone sees it even if they don't belong to a suitable group) - from
* course_modules table
* @property-read bool $coursegroupmodeforce Indicates whether the course containing the module has forced the groupmode
* This means that cm_info::$groupmode should be ignored and cm_info::$coursegroupmode be used instead
* @property-read int $coursegroupmode Group mode (one of the constants NOGROUPS, SEPARATEGROUPS, or VISIBLEGROUPS) - from
* course table - as specified for the course containing the module
* Effective only if {@link cm_info::$coursegroupmodeforce} is set
* @property-read int $effectivegroupmode Effective group mode for this module (one of the constants NOGROUPS, SEPARATEGROUPS,
* or VISIBLEGROUPS). This can be different from groupmode set for the module if the groupmode is forced for the course.
* This value will always be NOGROUPS if module type does not support group mode.
* @property-read int $indent Indent level on course page (0 = no indent) - from course_modules table
* @property-read int $completion Activity completion setting for this activity, COMPLETION_TRACKING_xx constant - from
* course_modules table
* @property-read mixed $completiongradeitemnumber Set to the item number (usually 0) if completion depends on a particular
* grade of this activity, or null if completion does not depend on a grade - from course_modules table
* @property-read int $completionview 1 if 'on view' completion is enabled, 0 otherwise - from course_modules table
* @property-read int $completionexpected Set to a unix time if completion of this activity is expected at a
* particular time, 0 if no time set - from course_modules table
* @property-read int $availablefrom Available date for this activity (0 if not set, or set to seconds since epoch; before this
* date, activity does not display to students) - from course_modules table
* @property-read int $availableuntil Available until date for this activity (0 if not set, or set to seconds since epoch; from
* this date, activity does not display to students) - from course_modules table
* @property-read int $showavailability When activity is unavailable, this field controls whether it is shown to students (0 =
* hide completely, 1 = show greyed out with information about when it will be available) -
* from course_modules table
* @property-read int $showdescription Controls whether the description of the activity displays on the course main page (in
* addition to anywhere it might display within the activity itself). 0 = do not show
* on main page, 1 = show on main page.
* @property-read string $extra (deprecated) Extra HTML that is put in an unhelpful part of the HTML when displaying this module in
* course page - from cached data in modinfo field. Deprecated, replaced by ->extraclasses and ->onclick
* @property-read string $icon Name of icon to use - from cached data in modinfo field
* @property-read string $iconcomponent Component that contains icon - from cached data in modinfo field
* @property-read string $modname Name of module e.g. 'forum' (this is the same name as the module's main database
* table) - from cached data in modinfo field
* @property-read int $module ID of module type - from course_modules table
* @property-read string $name Name of module instance for display on page e.g. 'General discussion forum' - from cached
* data in modinfo field
* @property-read int $sectionnum Section number that this course-module is in (section 0 = above the calendar, section 1
* = week/topic 1, etc) - from cached data in modinfo field
* @property-read int $section Section id - from course_modules table
* @property-read array $conditionscompletion Availability conditions for this course-module based on the completion of other
* course-modules (array from other course-module id to required completion state for that
* module) - from cached data in modinfo field
* @property-read array $conditionsgrade Availability conditions for this course-module based on course grades (array from
* grade item id to object with ->min, ->max fields) - from cached data in modinfo field
* @property-read array $conditionsfield Availability conditions for this course-module based on user fields
* @property-read bool $available True if this course-module is available to students i.e. if all availability conditions
* are met - obtained dynamically
* @property-read string $availableinfo If course-module is not available to students, this string gives information about
* availability which can be displayed to students and/or staff (e.g. 'Available from 3
* January 2010') for display on main page - obtained dynamically
* @property-read bool $uservisible True if this course-module is available to the CURRENT user (for example, if current user
* has viewhiddenactivities capability, they can access the course-module even if it is not
* visible or not available, so this would be true in that case)
* @property-read context_module $context Module context
* @property-read string $modfullname Returns a localised human-readable name of the module type - calculated on request
* @property-read string $modplural Returns a localised human-readable name of the module type in plural form - calculated on request
* @property-read string $content Content to display on main (view) page - calculated on request
* @property-read moodle_url $url URL to link to for this module, or null if it doesn't have a view page - calculated on request
* @property-read string $extraclasses Extra CSS classes to add to html output for this activity on main page - calculated on request
* @property-read string $onclick Content of HTML on-click attribute already escaped - calculated on request
* @property-read mixed $customdata Optional custom data stored in modinfo cache for this activity, or null if none
* @property-read string $afterlink Extra HTML code to display after link - calculated on request
* @property-read string $afterediticons Extra HTML code to display after editing icons (e.g. more icons) - calculated on request
*/
class cm_info implements IteratorAggregate {
/**
* State: Only basic data from modinfo cache is available.
*/
const STATE_BASIC = 0;
/**
* State: In the process of building dynamic data (to avoid recursive calls to obtain_dynamic_data())
*/
const STATE_BUILDING_DYNAMIC = 1;
/**
* State: Dynamic data is available too.
*/
const STATE_DYNAMIC = 2;
/**
* State: In the process of building view data (to avoid recursive calls to obtain_view_data())
*/
const STATE_BUILDING_VIEW = 3;
/**
* State: View data (for course page) is available.
*/
const STATE_VIEW = 4;
/**
* Parent object
* @var course_modinfo
*/
private $modinfo;
/**
* Level of information stored inside this object (STATE_xx constant)
* @var int
*/
private $state;
/**
* Course-module ID - from course_modules table
* @var int
*/
private $id;
/**
* Module instance (ID within module table) - from course_modules table
* @var int
*/
private $instance;
/**
* 'ID number' from course-modules table (arbitrary text set by user) - from
* course_modules table
* @var string
*/
private $idnumber;
/**
* Time that this course-module was added (unix time) - from course_modules table
* @var int
*/
private $added;
/**
* This variable is not used and is included here only so it can be documented.
* Once the database entry is removed from course_modules, it should be deleted
* here too.
* @var int
* @deprecated Do not use this variable
*/
private $score;
/**
* Visible setting (0 or 1; if this is 0, students cannot see/access the activity) - from
* course_modules table
* @var int
*/
private $visible;
/**
* Old visible setting (if the entire section is hidden, the previous value for
* visible is stored in this field) - from course_modules table
* @var int
*/
private $visibleold;
/**
* Group mode (one of the constants NONE, SEPARATEGROUPS, or VISIBLEGROUPS) - from
* course_modules table
* @var int
*/
private $groupmode;
/**
* Grouping ID (0 = all groupings)
* @var int
*/
private $groupingid;
/**
* Group members only (if set to 1, only members of a suitable group see this link on the
* course page; 0 = everyone sees it even if they don't belong to a suitable group) - from
* course_modules table
* @var int
*/
private $groupmembersonly;
/**
* Indent level on course page (0 = no indent) - from course_modules table
* @var int
*/
private $indent;
/**
* Activity completion setting for this activity, COMPLETION_TRACKING_xx constant - from
* course_modules table
* @var int
*/
private $completion;
/**
* Set to the item number (usually 0) if completion depends on a particular
* grade of this activity, or null if completion does not depend on a grade - from
* course_modules table
* @var mixed
*/
private $completiongradeitemnumber;
/**
* 1 if 'on view' completion is enabled, 0 otherwise - from course_modules table
* @var int
*/
private $completionview;
/**
* Set to a unix time if completion of this activity is expected at a
* particular time, 0 if no time set - from course_modules table
* @var int
*/
private $completionexpected;
/**
* Available date for this activity (0 if not set, or set to seconds since epoch; before this
* date, activity does not display to students) - from course_modules table
* @var int
*/
private $availablefrom;
/**
* Available until date for this activity (0 if not set, or set to seconds since epoch; from
* this date, activity does not display to students) - from course_modules table
* @var int
*/
private $availableuntil;
/**
* When activity is unavailable, this field controls whether it is shown to students (0 =
* hide completely, 1 = show greyed out with information about when it will be available) -
* from course_modules table
* @var int
*/
private $showavailability;
/**
* Controls whether the description of the activity displays on the course main page (in
* addition to anywhere it might display within the activity itself). 0 = do not show
* on main page, 1 = show on main page.
* @var int
*/
private $showdescription;
/**
* Extra HTML that is put in an unhelpful part of the HTML when displaying this module in
* course page - from cached data in modinfo field
* @deprecated This is crazy, don't use it. Replaced by ->extraclasses and ->onclick
* @var string
*/
private $extra;
/**
* Name of icon to use - from cached data in modinfo field
* @var string
*/
private $icon;
/**
* Component that contains icon - from cached data in modinfo field
* @var string
*/
private $iconcomponent;
/**
* Name of module e.g. 'forum' (this is the same name as the module's main database
* table) - from cached data in modinfo field
* @var string
*/
private $modname;
/**
* ID of module - from course_modules table
* @var int
*/
private $module;
/**
* Name of module instance for display on page e.g. 'General discussion forum' - from cached
* data in modinfo field
* @var string
*/
private $name;
/**
* Section number that this course-module is in (section 0 = above the calendar, section 1
* = week/topic 1, etc) - from cached data in modinfo field
* @var int
*/
private $sectionnum;
/**
* Section id - from course_modules table
* @var int
*/
private $section;
/**
* Availability conditions for this course-module based on the completion of other
* course-modules (array from other course-module id to required completion state for that
* module) - from cached data in modinfo field