Page existence and metadata cache. More...

Inherits LoggerAwareInterface.

Collaboration diagram for MediaWiki\Page\LinkCache:

Public Member Functions
	__construct (TitleFormatter $titleFormatter, WANObjectCache $cache, NamespaceInfo $nsInfo, ?ILoadBalancer $loadBalancer=null)

	addBadLinkObj ( $page, int $queryFlags=IDBAccessObject::READ_NORMAL)
	Add information about a missing page to the process cache.

	addGoodLinkObjFromRow ( $page, stdClass $row, int $queryFlags=IDBAccessObject::READ_NORMAL)
	Add information about an existing page to the process cache.

	addLinkObj ( $page, int $queryFlags=IDBAccessObject::READ_NORMAL)
	Add a title to the link cache, return the page_id or zero if non-existent.

	clear ()
	Clears cache.

	clearBadLink ( $page)
	Clear information about a page being missing from the process cache.

	clearLink ( $page)
	Clear information about a page from the process cache.

	getGoodLinkFieldObj ( $page, string $field)
	Get the field of a page known to the process cache.

	getGoodLinkID ( $page)
	Get the ID of a page known to the process cache.

	getGoodLinkRow (int $ns, string $dbkey, ?callable $fetchCallback=null, int $queryFlags=IDBAccessObject::READ_NORMAL)
	Returns the row for the page if the page exists (subject to race conditions).

	invalidateTitle ( $page)
	Purge the persistent link cache for a title.

	isBadLink ( $page)
	Check if a page is known to be missing based on the process cache.

	setLogger (LoggerInterface $logger)

Static Public Member Functions
static	getSelectFields ()
	Fields that LinkCache needs to select.

Detailed Description

Page existence and metadata cache.

This is exists primarily to reduce heavy database load from the Parser when rendering each individual outgoing link and template transclusion when parsing wikitext.

See the architecture doc at docs/LinkCache.md for more information.

To create a batch, you can use the following code:

$titles = [];
foreach ( [ 'Main Page', 'Project:Help' ] as $page ) {
  $titles[] = Title::newFromText( $page );
}
$linkBatchFactory = MediaWikiServices::getInstance()->getLinkBatchFactory();
$linkBatchFactory->newLinkBatch( $titles )->setCaller( __METHOD__ )->execute();

See also: MediaWiki\Page\LinkBatchFactory; MediaWiki\Page\LinkBatch

Since: 1.1

Definition at line 53 of file LinkCache.php.

Constructor & Destructor Documentation

◆ __construct()

MediaWiki\Page\LinkCache::__construct	(	TitleFormatter	$titleFormatter,
		WANObjectCache	$cache,
		NamespaceInfo	$nsInfo,
		?ILoadBalancer	$loadBalancer = null )

Parameters

TitleFormatter	$titleFormatter
WANObjectCache	$cache
NamespaceInfo	$nsInfo
ILoadBalancer \| null	$loadBalancer	Use null when no database is set up, for example on installation

Definition at line 81 of file LinkCache.php.

Member Function Documentation

◆ addBadLinkObj()

MediaWiki\Page\LinkCache::addBadLinkObj	(		$page,
		int	$queryFlags = IDBAccessObject::READ_NORMAL )

Add information about a missing page to the process cache.

Callers must set the READ_LATEST flag if the row came from a DB_PRIMARY source. However, the use of such data is highly discouraged; most callers rely on seeing consistent DB_REPLICA data (e.g. REPEATABLE-READ point-in-time snapshots) and the accidental use of DB_PRIMARY data via LinkCache is prone to causing anomalies.

Parameters

LinkTarget \| PageReference \| array	$page	The page to set cached info for. Can be given as an object or an associative array containing the page_namespace and page_title fields. In MediaWiki 1.36 and earlier, only LinkTarget was accepted.
int	$queryFlags	The query flags used to retrieve the row, IDBAccessObject::READ_*

Definition at line 299 of file LinkCache.php.

◆ addGoodLinkObjFromRow()

MediaWiki\Page\LinkCache::addGoodLinkObjFromRow	(		$page,
		stdClass	$row,
		int	$queryFlags = IDBAccessObject::READ_NORMAL )

Add information about an existing page to the process cache.

Callers must set the READ_LATEST flag if the row came from a DB_PRIMARY source. However, the use of such data is highly discouraged; most callers rely on seeing consistent DB_REPLICA data (e.g. REPEATABLE-READ point-in-time snapshots) and the accidental use of DB_PRIMARY data via LinkCache is prone to causing anomalies.

Parameters

LinkTarget \| PageReference \| array	$page	The page to set cached info for. Can be given as an object or an associative array containing the page_namespace and page_title fields. In MediaWiki 1.36 and earlier, only LinkTarget was accepted.
stdClass	$row	Object which has all fields returned by getSelectFields().
int	$queryFlags	The query flags used to retrieve the row, IDBAccessObject::READ_*

Since: 1.19

Definition at line 266 of file LinkCache.php.

◆ addLinkObj()

MediaWiki\Page\LinkCache::addLinkObj	(		$page,
		int	$queryFlags = IDBAccessObject::READ_NORMAL )

Add a title to the link cache, return the page_id or zero if non-existent.

This causes the link to be looked up in the database if it is not yet cached.

Deprecated: since 1.37, use PageStore::getPageForLink() instead.

Parameters

LinkTarget \| PageReference \| array	$page	The page to load. Can be given as an object or an associative array containing the page_namespace and page_title fields. In MediaWiki 1.36 and earlier, only LinkTarget was accepted.
int	$queryFlags	IDBAccessObject::READ_XXX

Returns: int Page ID or zero

Definition at line 382 of file LinkCache.php.

◆ clear()

MediaWiki\Page\LinkCache::clear ( )

Clears cache.

Definition at line 582 of file LinkCache.php.

◆ clearBadLink()

MediaWiki\Page\LinkCache::clearBadLink ( $page )

Clear information about a page being missing from the process cache.

Parameters

LinkTarget | PageReference | array | string $page The page to clear cached info for, as an object, an array containing the page_namespace and page_title fields, or a prefixed DB key. In MediaWiki 1.36 and earlier, only a string was accepted. In MediaWiki 1.36 and earlier, only a string was accepted.

Definition at line 316 of file LinkCache.php.

◆ clearLink()

MediaWiki\Page\LinkCache::clearLink ( $page )

Clear information about a page from the process cache.

Parameters

LinkTarget | PageReference | array $page The page to clear cached info for. Can be given as an object or an associative array containing the page_namespace and page_title fields. In MediaWiki 1.36 and earlier, only LinkTarget was accepted.

Definition at line 336 of file LinkCache.php.

◆ getGoodLinkFieldObj()

MediaWiki\Page\LinkCache::getGoodLinkFieldObj	(		$page,
		string	$field )

Get the field of a page known to the process cache.

If this link is not a cached good title, it will return NULL.

Parameters

LinkTarget \| PageReference \| array	$page	The page to get cached info for. Can be given as an object or an associative array containing the page_namespace and page_title fields. In MediaWiki 1.36 and earlier, only LinkTarget was accepted.
string	$field	( 'id', 'length', 'redirect', 'revision', 'model', 'lang' )

Returns: string|int|null The field value, or null if the page was not cached or does not exist or is not a proper page (e.g. a special page or interwiki link).

Definition at line 192 of file LinkCache.php.

◆ getGoodLinkID()

MediaWiki\Page\LinkCache::getGoodLinkID ( $page )

Get the ID of a page known to the process cache.

Parameters

LinkTarget | PageReference | array | string $page The page to get the ID for, as an object, an array containing the page_namespace and page_title fields, or a prefixed DB key. In MediaWiki 1.36 and earlier, only a string was accepted.

Returns: int Page ID, or zero if the page was not cached or does not exist or is not a proper page (e.g. a special page or an interwiki link).

Definition at line 164 of file LinkCache.php.

◆ getGoodLinkRow()

MediaWiki\Page\LinkCache::getGoodLinkRow	(	int	$ns,
		string	$dbkey,
		?callable	$fetchCallback = null,
		int	$queryFlags = IDBAccessObject::READ_NORMAL )

Returns the row for the page if the page exists (subject to race conditions).

The row will be returned from local cache or WAN cache if possible, or it will be looked up using the callback provided.

Parameters

int	$ns
string	$dbkey
callable \| null	$fetchCallback	A callback that will retrieve the link row with the signature ( IReadableDatabase $db, int $ns, string $dbkey, array $queryOptions ): ?stdObj.
int	$queryFlags	IDBAccessObject::READ_XXX

Returns: stdClass|null

Access: internal: for use by PageStore. Other code should use a PageLookup instead.

Definition at line 477 of file LinkCache.php.

◆ getSelectFields()

static MediaWiki\Page\LinkCache::getSelectFields ( )

static

Fields that LinkCache needs to select.

Since: 1.28

Returns: array

Definition at line 349 of file LinkCache.php.

References MediaWiki\MediaWikiServices\getInstance(), MediaWiki\MainConfigNames\PageLanguageUseDB, and MediaWiki\Page\PageStoreRecord\REQUIRED_FIELDS.

◆ invalidateTitle()

MediaWiki\Page\LinkCache::invalidateTitle ( $page )

Purge the persistent link cache for a title.

Parameters

LinkTarget | PageReference $page In MediaWiki 1.36 and earlier, only LinkTarget was accepted.

Since: 1.28

Definition at line 570 of file LinkCache.php.

◆ isBadLink()

MediaWiki\Page\LinkCache::isBadLink ( $page )

Check if a page is known to be missing based on the process cache.

Parameters

LinkTarget | PageReference | array | string $page The page to get cached info for, as an object, an array containing the page_namespace and page_title fields, or a prefixed DB key. In MediaWiki 1.36 and earlier, only a string was accepted. In MediaWiki 1.36 and earlier, only a string was accepted.

Returns: bool Whether the page is known to be missing based on the process cache

Definition at line 239 of file LinkCache.php.

◆ setLogger()

MediaWiki\Page\LinkCache::setLogger ( LoggerInterface $logger )

Definition at line 95 of file LinkCache.php.

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

includes/Page/LinkCache.php

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ addBadLinkObj()

◆ addGoodLinkObjFromRow()

◆ addLinkObj()

◆ clear()

◆ clearBadLink()

◆ clearLink()

◆ getGoodLinkFieldObj()

◆ getGoodLinkID()

◆ getGoodLinkRow()

◆ getSelectFields()

◆ invalidateTitle()

◆ isBadLink()

◆ setLogger()