context Class Reference

Inheritance diagram for context:

Public Member Functions
	__get ($name)
	Magic method getter, redirects to read only values. More...
	__isset ($name)
	Full support for isset on our magic read only properties. More...
	__set ($name, $value)
	Magic setter method, we do not want anybody to modify properties from the outside. More...
	__unset ($name)
	All properties are read only, sorry. More...
	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 ()
	Returns array of relevant context capability records. More...
	get_child_contexts ()
	Recursive function which, given a context, find all its children context ids. More...
	get_context_name ($withprefix=true, $short=false)
	Returns human readable context identifier. More...
	get_course_context ($strict=true)
	Is this context part of any course? If yes return course context. More...
	get_parent_context ()
	Returns parent context. More...
	get_parent_context_ids ($includeself=false)
	Returns parent context ids of this context in reversed order, i.e. More...
	get_parent_context_paths ($includeself=false)
	Returns parent context paths of this context. More...
	get_parent_contexts ($includeself=false)
	Returns parent contexts of this context in reversed order, i.e. More...
	get_url ()
	Returns the most relevant URL for this context. More...
	getIterator ()
	Create an iterator because magic vars can't be seen by 'foreach'. More...
	is_child_of (context $possibleparent, bool $includeself)
	Determine if the current context is a child of the possible parent. More...
	is_locked ()
	Whether the current context is locked. More...
	is_parent_of (context $possiblechild, bool $includeself)
	Determine if the current context is a parent of the possible child. More...
	mark_dirty ()
	Mark a context as dirty (with timestamp) so as to force reloading of the context.
	reload_if_dirty ()
	Reset all cached permissions and definitions if the necessary. More...
	reset_paths ($rebuild=true)
	Remove all context path info and optionally rebuild it. More...
	set_locked (bool $locked)
	Set whether this context has been locked or not. More...
	update_moved (context $newparent)
	Update context info after moving context in the tree structure. More...

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

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

Static Protected Member Functions
static	build_paths ($force)
	Rebuild context paths and depths at context level. More...
static	cache_add (context $context)
	Adds a context to the cache. More...
static	cache_get ($contextlevel, $instance)
	Gets a context from the cache. More...
static	cache_get_by_id ($id)
	Gets a context from the cache based on its id. More...
static	cache_remove (context $context)
	Removes a context from the cache. More...
static	create_instance_from_record (stdClass $record)
	This function is also used to work around 'protected' keyword problems in context_helper. More...
static	create_level_instances ()
	Create missing context instances at given level. More...
static	get_cleanup_sql ()
	Returns sql necessary for purging of stale context instances. More...
static	insert_context_record ($contextlevel, $instanceid, $parentpath)
	Utility method for context creation. More...
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. More...
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. More...
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. More...
int	$_locked
	Whether this context is locked or not. More...
string	$_path
	The path to the context always starting from the system context Can be accessed publicly through $context->path.

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.

Constructor & Destructor Documentation

__construct()

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 context_block, context_module, context_course, context_coursecat, context_user, and context_system.

Member Function Documentation

__get()

context::__get

(

$name

)

Magic method getter, redirects to read only values.

Parameters

string

$name

Return values

mixed

__isset()

context::__isset

(

$name

)

Full support for isset on our magic read only properties.

Parameters

string

$name

Return values

bool

__set()

context::__set	(		$name,
			$value
	)

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

Parameters

string	$name
mixed	$value

__unset()

context::__unset

(

$name

)

All properties are read only, sorry.

Parameters

string

$name

build_paths()

static context::build_paths (   $force )

staticprotected

Rebuild context paths and depths at context level.

Parameters

bool

$force

Return values

void

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, and context_system.

cache_add()

static 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 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 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 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 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 context::create_level_instances ( )

staticprotected

Create missing context instances at given level.

Return values

void

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, and context_system.

get_capabilities()

context::get_capabilities ( )

abstract

Returns array of relevant context capability records.

Return values

array

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, context_system, and context_helper.

get_child_contexts()

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 context_block, context_coursecat, and context_system.

get_cleanup_sql()

static context::get_cleanup_sql ( )

staticprotected

Returns sql necessary for purging of stale context instances.

Return values

string

cleanup SQL

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, and context_system.

get_context_name()

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

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

Return values

string

the human readable context name.

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, and context_system.

get_course_context()

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

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

Reimplemented in context_block, context_module, and context_course.

get_parent_context()

context::get_parent_context

(

)

Returns parent context.

Return values

context

get_parent_context_ids()

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()

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()

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_url()

context::get_url ( )

abstract

Returns the most relevant URL for this context.

Return values

moodle_url

Reimplemented in context_block, context_module, context_course, context_coursecat, context_user, context_system, and context_helper.

getIterator()

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 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 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()

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()

context::is_locked

(

)

Whether the current context is locked.

Return values

bool

is_parent_of()

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 context::preload_from_record ( stdClass  $rec )

staticprotected

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

Parameters

stdClass

$rec

Return values

void	(modifies $rec)

Reimplemented in context_helper.

reload_if_dirty()

context::reload_if_dirty

(

)

Reset all cached permissions and definitions if the necessary.

Return values

void

reset_paths()

context::reset_paths

(

$rebuild = true

)

Remove all context path info and optionally rebuild it.

Parameters

bool

$rebuild

Return values

void

set_locked()

context::set_locked

(

bool

$locked

)

Set whether this context has been locked or not.

Parameters

bool

$locked

Return values

$this

Reimplemented in context_system.

update_moved()

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 context::$_contextlevel

protected

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

CONTEXT_COURSE, CONTEXT_MODULE

$_instanceid

int 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 context::$_locked

protected

Whether this context is locked or not.

Can be accessed publicly through $context->locked.

---

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

• lib/accesslib.php