Basic moodle context abstraction class. More...

Inheritance diagram for core\context:

Public Member Functions
	__get ($name)
	Magic method getter, redirects to read only values.

	__isset ($name)
	Full support for isset on our magic read only properties.

	__set ($name, $value)
	Magic setter method, we do not want anybody to modify properties from the outside.

	__unset ($name)
	All properties are read only, sorry.

	delete ()
	Delete the context content and the context record itself.

	delete_capabilities ()
	Unassign all capabilities from a context.

	delete_content ()
	Delete all data linked to content, do not delete the context record itself.

	get_capabilities (string $sort=self::DEFAULT_CAPABILITY_SORT)
	Returns array of relevant context capability records.

	get_child_contexts ()
	Recursive function which, given a context, find all its children context ids.

	get_context_name ($withprefix=true, $short=false, $escape=true)
	Returns human readable context identifier.

	get_course_context ($strict=true)
	Is this context part of any course? If yes return course context.

	get_parent_context ()
	Returns parent context.

	get_parent_context_ids ($includeself=false)
	Returns parent context ids of this context in reversed order, i.e.

	get_parent_context_paths ($includeself=false)
	Returns parent context paths of this context.

	get_parent_contexts ($includeself=false)
	Returns parent contexts of this context in reversed order, i.e.

	get_url ()
	Returns the most relevant URL for this context.

	getIterator ()
	Create an iterator because magic vars can't be seen by 'foreach'.

	is_child_of (context $possibleparent, bool $includeself)
	Determine if the current context is a child of the possible parent.

	is_locked ()
	Whether the current context is locked.

	is_parent_of (context $possiblechild, bool $includeself)
	Determine if the current context is a parent of the possible child.

	mark_dirty ()
	Mark a context as dirty (with timestamp) so as to force reloading of the context.

	reload_if_dirty ()
	Reset all cached permissions and definitions if the necessary.

	reset_paths ($rebuild=true)
	Remove all context path info and optionally rebuild it.

	set_locked (bool $locked)
	Set whether this context has been locked or not.

	update_moved (context $newparent)
	Update context info after moving context in the tree structure.

Static Public Member Functions
static	get_possible_parent_levels ()
	Returns list of all possible parent context levels, it may include itself if nesting is allowed.

static	get_short_name ()
	Returns short context name.

static	instance_by_id ($id, $strictness=MUST_EXIST)
	Get a context instance as an object, from a given context id.

Protected Member Functions
	__construct (stdClass $record)
	Constructor is protected so that devs are forced to use context_xxx\instance() or context\instance_by_id().

Static Protected Member Functions
static	build_paths ($force)
	Rebuild context paths and depths at context level.

static	cache_add (context $context)
	Adds a context to the cache.

static	cache_get ($contextlevel, $instance)
	Gets a context from the cache.

static	cache_get_by_id ($id)
	Gets a context from the cache based on its id.

static	cache_remove (context $context)
	Removes a context from the cache.

static	create_instance_from_record (stdClass $record)
	This function is also used to work around 'protected' keyword problems in context_helper.

static	create_level_instances ()
	Create missing context instances at given level.

static	get_behat_reference_columns ()
	Returns list of columns that can be used from behat to look up context by reference.

static	get_cleanup_sql ()
	Returns sql necessary for purging of stale context instances.

static	get_compatible_role_archetypes ()
	Returns list of all role archetypes that are compatible with role assignments in context level.

static	get_instance_table ()
	Returns context instance database name.

static	insert_context_record ($contextlevel, $instanceid, $parentpath)
	Utility method for context creation.

static	merge_context_temp_table ()
	Copy prepared new contexts from temp table to context table, we do this in db specific way for perf reasons only.

static	preload_from_record (stdClass $rec)
	Preloads context information from db record and strips the cached info.

static	reset_caches ()
	Resets the cache to remove all data.

Protected Attributes
int	$_contextlevel
	The context level Can be accessed publicly through $context->contextlevel One of CONTEXT_* e.g.

int	$_depth
	The depth of the context in relation to parent contexts Can be accessed publicly through $context->depth.

int	$_id
	The context id Can be accessed publicly through $context->id.

int	$_instanceid
	Id of the item this context is related to e.g.

int	$_locked
	Whether this context is locked or not.

string	$_path
	The path to the context always starting from the system context Can be accessed publicly through $context->path.

string const	DEFAULT_CAPABILITY_SORT = 'contextlevel, component, name'
	Default sorting of capabilities in {.

Static Protected Attributes
static int	$cache_count = 0
	Context count Why do we do count contexts? Because count($array) is horribly slow for large arrays.

static array	$cache_preloaded = array()
	Context caching info.

static context system	$systemcontext = null
	The system context once initialised.

Detailed Description

Basic moodle context abstraction class.

Google confirms that no other important framework is using "context" class, we could use something else like mcontext or moodle_context, but we need to type this very often which would be annoying and it would take too much space...

This class is derived from stdClass for backwards compatibility with odl $context record that was returned from DML $DB->get_record()

Copyright: Petr Skoda

License: https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Since: Moodle 4.2

Constructor & Destructor Documentation

◆ __construct()

core\context::__construct ( stdClass $record )

protected

Constructor is protected so that devs are forced to use context_xxx\instance() or context\instance_by_id().

Parameters

stdClass $record

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

Member Function Documentation

◆ __get()

core\context::__get ( $name )

Magic method getter, redirects to read only values.

Parameters

string $name

Return values

mixed

◆ __isset()

core\context::__isset ( $name )

Full support for isset on our magic read only properties.

Parameters

string $name

Return values

bool

◆ __set()

core\context::__set	(		$name,
			$value )

Magic setter method, we do not want anybody to modify properties from the outside.

Parameters

string	$name
mixed	$value

◆ __unset()

core\context::__unset ( $name )

All properties are read only, sorry.

Parameters

string $name

◆ build_paths()

static core\context::build_paths ( $force )

staticprotected

Rebuild context paths and depths at context level.

Parameters

bool $force

Return values

void

Reimplemented in core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ cache_add()

static core\context::cache_add ( context $context )

staticprotected

Adds a context to the cache.

If the cache is full, discards a batch of older entries.

Parameters

context $context New context to add

Return values

void

◆ cache_get()

static core\context::cache_get	(		$contextlevel,
			$instance )

staticprotected

Gets a context from the cache.

Parameters

int	$contextlevel	Context level
int	$instance	Instance ID

Return values

context|bool Context or false if not in cache

◆ cache_get_by_id()

static core\context::cache_get_by_id ( $id )

staticprotected

Gets a context from the cache based on its id.

Parameters

int $id Context ID

Return values

context|bool Context or false if not in cache

◆ cache_remove()

static core\context::cache_remove ( context $context )

staticprotected

Removes a context from the cache.

Parameters

context $context Context object to remove

Return values

void

◆ create_instance_from_record()

static core\context::create_instance_from_record ( stdClass $record )

staticprotected

This function is also used to work around 'protected' keyword problems in context_helper.

Parameters

stdClass $record

Return values

context instance

◆ create_level_instances()

static core\context::create_level_instances ( )

staticprotected

Create missing context instances at given level.

Return values

void

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_behat_reference_columns()

static core\context::get_behat_reference_columns ( )

staticprotected

Returns list of columns that can be used from behat to look up context by reference.

Return values

array list of column names from instance table

Reimplemented in core\context\course, core\context\coursecat, core\context\module, and core\context\user.

◆ get_capabilities()

core\context::get_capabilities ( string $sort = self::DEFAULT_CAPABILITY_SORT )

abstract

Returns array of relevant context capability records.

Parameters

string $sort SQL order by snippet for sorting returned capabilities sensibly for display

Return values

array

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_child_contexts()

core\context::get_child_contexts ( )

Recursive function which, given a context, find all its children context ids.

For course category contexts it will return immediate children and all subcategory contexts. It will NOT recurse into courses or subcategories categories. If you want to do that, call it on the returned courses/categories.

When called for a course context, it will return the modules and blocks displayed in the course page and blocks displayed on the module pages.

If called on a user/course/module context it will populate the cache with the appropriate contexts ;-)

Return values

array Array of child records

Reimplemented in core\context\block, core\context\coursecat, and core\context\system.

◆ get_cleanup_sql()

static core\context::get_cleanup_sql ( )

staticprotected

Returns sql necessary for purging of stale context instances.

Return values

string cleanup SQL

Reimplemented in core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_compatible_role_archetypes()

static core\context::get_compatible_role_archetypes ( )

staticprotected

Returns list of all role archetypes that are compatible with role assignments in context level.

Since: Moodle 4.2

Return values

string[]

Reimplemented in core\context\course, core\context\coursecat, core\context\module, and core\context\system.

◆ get_context_name()

core\context::get_context_name	(	$withprefix = true,
		$short = false,
		$escape = true )

Returns human readable context identifier.

Parameters

boolean	$withprefix	whether to prefix the name of the context with the type of context, e.g. User, Course, Forum, etc.
boolean	$short	whether to use the short name of the thing. Only applies to course contexts
boolean	$escape	Whether the returned name of the thing is to be HTML escaped or not.

Return values

string the human readable context name.

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_course_context()

core\context::get_course_context ( $strict = true )

Is this context part of any course? If yes return course context.

Parameters

bool $strict true means throw exception if not found, false means return false if not found

Return values

context\course|false context of the enclosing course, null if not found or exception

Reimplemented in core\context\block, core\context\course, and core\context\module.

◆ get_instance_table()

static core\context::get_instance_table ( )

staticprotected

Returns context instance database name.

Return values

string|null table name for all levels except system.

Reimplemented in core\context\course, core\context\coursecat, core\context\module, and core\context\user.

◆ get_parent_context()

core\context::get_parent_context ( )

Returns parent context.

Return values

context|false

◆ get_parent_context_ids()

core\context::get_parent_context_ids ( $includeself = false )

Returns parent context ids of this context in reversed order, i.e.

parent first, then grand parent, etc.

Parameters

bool $includeself true means include self too

Return values

array of context ids

◆ get_parent_context_paths()

core\context::get_parent_context_paths ( $includeself = false )

Returns parent context paths of this context.

Parameters

bool $includeself true means include self too

Return values

array of context paths

◆ get_parent_contexts()

core\context::get_parent_contexts ( $includeself = false )

Returns parent contexts of this context in reversed order, i.e.

parent first, then grand parent, etc.

Parameters

bool $includeself true means include self too

Return values

array of context instances

◆ get_possible_parent_levels()

static core\context::get_possible_parent_levels ( )

static

Returns list of all possible parent context levels, it may include itself if nesting is allowed.

Since: Moodle 4.2

Return values

int[]

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_short_name()

static core\context::get_short_name ( )

static

Returns short context name.

Since: Moodle 4.2

Return values

string

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ get_url()

core\context::get_url ( )

abstract

Returns the most relevant URL for this context.

Return values

moodle_url

Reimplemented in core\context\block, core\context\course, core\context\coursecat, core\context\module, core\context\system, and core\context\user.

◆ getIterator()

core\context::getIterator ( )

Create an iterator because magic vars can't be seen by 'foreach'.

Now we can convert context object to array using convert_to_array(), and feed it properly to json_encode().

◆ insert_context_record()

static core\context::insert_context_record	(	$contextlevel,
		$instanceid,
		$parentpath )

staticprotected

Utility method for context creation.

Parameters

int	$contextlevel
int	$instanceid
string	$parentpath

Return values

stdClass context record

◆ instance_by_id()

static core\context::instance_by_id	(		$id,
			$strictness = MUST_EXIST )

static

Get a context instance as an object, from a given context id.

Parameters

int	$id	context id
int	$strictness	IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found; MUST_EXIST means throw exception if no record found

Return values

context|bool the context object or false if not found

◆ is_child_of()

core\context::is_child_of	(	context	$possibleparent,
		bool	$includeself )

Determine if the current context is a child of the possible parent.

Parameters

context	$possibleparent
bool	$includeself	Whether to check the current context

Return values

bool

◆ is_locked()

core\context::is_locked ( )

Whether the current context is locked.

Return values

bool

◆ is_parent_of()

core\context::is_parent_of	(	context	$possiblechild,
		bool	$includeself )

Determine if the current context is a parent of the possible child.

Parameters

context	$possiblechild
bool	$includeself	Whether to check the current context

Return values

bool

◆ preload_from_record()

static core\context::preload_from_record ( stdClass $rec )

staticprotected

Preloads context information from db record and strips the cached info.

Parameters

stdClass $rec

Return values

context|null (modifies $rec)

Reimplemented in core\context_helper.

◆ reload_if_dirty()

core\context::reload_if_dirty ( )

Reset all cached permissions and definitions if the necessary.

Return values

void

◆ reset_caches()

static core\context::reset_caches ( )

staticprotected

Resets the cache to remove all data.

Reimplemented in core\context_helper.

◆ reset_paths()

core\context::reset_paths ( $rebuild = true )

Remove all context path info and optionally rebuild it.

Parameters

bool $rebuild

Return values

void

◆ set_locked()

core\context::set_locked ( bool $locked )

Set whether this context has been locked or not.

Parameters

bool $locked

Return values

$this

Reimplemented in core\context\system.

◆ update_moved()

core\context::update_moved ( context $newparent )

Update context info after moving context in the tree structure.

Parameters

context $newparent

Return values

void

Member Data Documentation

◆ $_contextlevel

int core\context::$_contextlevel

protected

The context level Can be accessed publicly through $context->contextlevel One of CONTEXT_* e.g.

CONTEXT_COURSE, CONTEXT_MODULE

◆ $_instanceid

int core\context::$_instanceid

protected

Id of the item this context is related to e.g.

COURSE_CONTEXT => course.id Can be accessed publicly through $context->instanceid

◆ $_locked

int core\context::$_locked

protected

Whether this context is locked or not.

Can be accessed publicly through $context->locked.

◆ DEFAULT_CAPABILITY_SORT

string const core\context::DEFAULT_CAPABILITY_SORT = 'contextlevel, component, name'

protected

Default sorting of capabilities in {.

See also: get_capabilities}

The documentation for this class was generated from the following file:

lib/classes/context.php

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ __get()

◆ __isset()

◆ __set()

◆ __unset()

◆ build_paths()

◆ cache_add()

◆ cache_get()

◆ cache_get_by_id()

◆ cache_remove()

◆ create_instance_from_record()

◆ create_level_instances()

◆ get_behat_reference_columns()

◆ get_capabilities()

◆ get_child_contexts()

◆ get_cleanup_sql()

◆ get_compatible_role_archetypes()

◆ get_context_name()

◆ get_course_context()

◆ get_instance_table()

◆ get_parent_context()

◆ get_parent_context_ids()

◆ get_parent_context_paths()

◆ get_parent_contexts()

◆ get_possible_parent_levels()

◆ get_short_name()

◆ get_url()

◆ getIterator()

◆ insert_context_record()

◆ instance_by_id()

◆ is_child_of()

◆ is_locked()

◆ is_parent_of()

◆ preload_from_record()

◆ reload_if_dirty()

◆ reset_caches()

◆ reset_paths()

◆ set_locked()

◆ update_moved()

Member Data Documentation

◆ $_contextlevel

◆ $_instanceid

◆ $_locked

◆ DEFAULT_CAPABILITY_SORT