Class for fetching backlink lists, approximate backlink counts and partitions. More...

Collaboration diagram for BacklinkCache:

[legend]

Public Member Functions
	__construct (Title $title)
	Create a new BacklinkCache.

	__sleep ()
	Serialization handler, diasallows to serialize the database to prevent failures after this class is deserialized from cache with dead DB connection.

	clear ()
	Clear locally stored data and database object.

	getCascadeProtectedLinks ()
	Get a Title iterator for cascade-protected template/file use backlinks.

	getLinks ( $table, $startId=false, $endId=false, $max=INF)
	Get the backlinks for a given table.

	getNumLinks ( $table, $max=INF)
	Get the approximate number of backlinks.

	hasLinks ( $table)
	Check if there are any backlinks.

	partition ( $table, $batchSize)
	Partition the backlinks into batches.

	setDB ( $db)
	Set the Database object to use.

Static Public Member Functions
static	get (Title $title)
	Create a new BacklinkCache or reuse any existing one.

Protected Member Functions
	getConditions ( $table)
	Get the SQL condition array for selecting backlinks, with a join on the page table.

	getDB ()
	Get the replica DB connection to the database When non existing, will initialize the connection.

	getPrefix ( $table)
	Get the field name prefix for a given table.

	partitionResult ( $res, $batchSize, $isComplete=true)
	Partition a DB result with backlinks in it into batches.

	queryLinks ( $table, $startId, $endId, $max, $select='all')
	Get the backlinks for a given table.

Protected Attributes
	$db
	Local copy of a database object.

IResultWrapper[]	$fullResultCache = []
	Contains the whole links from a database result.

array[]	$partitionCache = []
	Multi dimensions array representing batches.

	$title
	Local copy of a Title object.

WANObjectCache	$wanCache

Static Protected Attributes
static BacklinkCache	$instance

Private Member Functions
	makeCheckKey ()
	Returns check key for the backlinks cache for a particular title.

Private Attributes
const	CACHE_EXPIRY = 3600

Detailed Description

Class for fetching backlink lists, approximate backlink counts and partitions.

This is a shared cache.

Instances of this class should typically be fetched with the method $title->getBacklinkCache().

Ideally you should only get your backlinks from here when you think there is some advantage in caching them. Otherwise it's just a waste of memory.

Introduced by r47317

Definition at line 47 of file BacklinkCache.php.

Constructor & Destructor Documentation

◆ __construct()

BacklinkCache::__construct ( Title $title )

Create a new BacklinkCache.

Parameters

Title $title : Title object to create a backlink cache for

Definition at line 103 of file BacklinkCache.php.

References $title.

Member Function Documentation

◆ __sleep()

BacklinkCache::__sleep ( )

Serialization handler, diasallows to serialize the database to prevent failures after this class is deserialized from cache with dead DB connection.

Returns: array

Definition at line 130 of file BacklinkCache.php.

◆ clear()

BacklinkCache::clear ( )

Clear locally stored data and database object.

Invalidate data in memcache.

Definition at line 137 of file BacklinkCache.php.

References makeCheckKey().

◆ get()

static BacklinkCache::get ( Title $title )

static

Create a new BacklinkCache or reuse any existing one.

Currently, only one cache instance can exist; callers that need multiple backlink cache objects should keep them in scope.

Parameters

Title $title Title object to get a backlink cache for

Returns: BacklinkCache

Definition at line 116 of file BacklinkCache.php.

References $instance, and $title.

Referenced by Title\getBacklinkCache().

◆ getCascadeProtectedLinks()

BacklinkCache::getCascadeProtectedLinks ( )

Get a Title iterator for cascade-protected template/file use backlinks.

Returns: TitleArray

Since: 1.25

Definition at line 524 of file BacklinkCache.php.

References $dbr, $res, getDB(), and NS_FILE.

◆ getConditions()

BacklinkCache::getConditions ( $table )

protected

Get the SQL condition array for selecting backlinks, with a join on the page table.

Parameters

string $table

Exceptions

MWException

Returns: array|null

Definition at line 278 of file BacklinkCache.php.

References getDB(), getPrefix(), and LIST_OR.

Referenced by queryLinks().

◆ getDB()

BacklinkCache::getDB ( )

protected

Get the replica DB connection to the database When non existing, will initialize the connection.

Returns: IDatabase

Definition at line 158 of file BacklinkCache.php.

References $db, DB_REPLICA, and wfGetDB().

Referenced by getCascadeProtectedLinks(), getConditions(), and queryLinks().

◆ getLinks()

BacklinkCache::getLinks	(	$table,
		$startId = `false`,
		$endId = `false`,
		$max = `INF`
	)

Get the backlinks for a given table.

Cached in process memory only.

Parameters

string	$table
int \| bool	$startId
int \| bool	$endId
int	$max

Returns: TitleArrayFromResult

Definition at line 174 of file BacklinkCache.php.

References queryLinks().

Referenced by getNumLinks().

◆ getNumLinks()

BacklinkCache::getNumLinks	(	$table,
		$max = `INF`
	)

Get the approximate number of backlinks.

Parameters

string	$table
int	$max	Only count up to this many backlinks

Returns: int

Definition at line 334 of file BacklinkCache.php.

References $wgUpdateRowsPerJob, getLinks(), makeCheckKey(), and partition().

Referenced by hasLinks().

◆ getPrefix()

BacklinkCache::getPrefix ( $table )

protected

Get the field name prefix for a given table.

Parameters

string $table

Exceptions

MWException

Returns: null|string

Definition at line 249 of file BacklinkCache.php.

Referenced by getConditions(), and queryLinks().

◆ hasLinks()

BacklinkCache::hasLinks ( $table )

Check if there are any backlinks.

Parameters

string $table

Returns: bool

Definition at line 324 of file BacklinkCache.php.

References getNumLinks().

◆ makeCheckKey()

BacklinkCache::makeCheckKey ( )

private

Returns check key for the backlinks cache for a particular title.

Returns: string

Definition at line 574 of file BacklinkCache.php.

Referenced by clear(), getNumLinks(), and partition().

◆ partition()

BacklinkCache::partition	(	$table,
		$batchSize
	)

Partition the backlinks into batches.

Returns an array giving the start and end of each range. The first batch has a start of false, and the last batch has an end of false.

Parameters

string	$table	The links table name
int	$batchSize

Returns: array

Definition at line 394 of file BacklinkCache.php.

References $res, makeCheckKey(), partitionResult(), queryLinks(), and wfDebug().

Referenced by getNumLinks().

◆ partitionResult()

BacklinkCache::partitionResult	(	$res,
		$batchSize,
		$isComplete = `true`
	)

protected

Partition a DB result with backlinks in it into batches.

Parameters

IResultWrapper	$res	Database result
int	$batchSize
bool	$isComplete	Whether $res includes all the backlinks

Exceptions

MWException

Returns: array

Definition at line 483 of file BacklinkCache.php.

References $res.

Referenced by partition().

◆ queryLinks()

BacklinkCache::queryLinks	(	$table,
		$startId,
		$endId,
		$max,
		$select = `'all'`
	)

protected

Get the backlinks for a given table.

Cached in process memory only.

Parameters

string	$table
int \| bool	$startId
int \| bool	$endId
int	$max
string	$select	'all' or 'ids'

Returns: IResultWrapper

Definition at line 187 of file BacklinkCache.php.

References $res, getConditions(), getDB(), getPrefix(), and wfDebug().

Referenced by getLinks(), and partition().

◆ setDB()

BacklinkCache::setDB ( $db )

Set the Database object to use.

Parameters

IDatabase $db

Definition at line 149 of file BacklinkCache.php.

References $db.

Member Data Documentation

◆ $db

BacklinkCache::$db

protected

Local copy of a database object.

Accessor: BacklinkCache::getDB() Mutator : BacklinkCache::setDB() Cleared with BacklinkCache::clear()

Definition at line 89 of file BacklinkCache.php.

Referenced by getDB(), and setDB().

◆ $fullResultCache

IResultWrapper [] BacklinkCache::$fullResultCache = []

protected

Contains the whole links from a database result.

This is raw data that will be partitioned in $partitionCache

Initialized with BacklinkCache::getLinks() Cleared with BacklinkCache::clear()

Definition at line 75 of file BacklinkCache.php.

◆ $instance

BacklinkCache BacklinkCache::$instance

staticprotected

Definition at line 51 of file BacklinkCache.php.

Referenced by get().

◆ $partitionCache

array [] BacklinkCache::$partitionCache = []

protected

Multi dimensions array representing batches.

Keys are:

‍(string) links table name (int) batch size 'numRows' : Number of rows for this link table 'batches' : [ $start, $end ]

See also: BacklinkCache::partitionResult()

Cleared with BacklinkCache::clear()

Definition at line 65 of file BacklinkCache.php.

◆ $title

BacklinkCache::$title

protected

Local copy of a Title object.

Definition at line 94 of file BacklinkCache.php.

Referenced by __construct(), and get().

◆ $wanCache

WANObjectCache BacklinkCache::$wanCache

protected

Definition at line 80 of file BacklinkCache.php.

◆ CACHE_EXPIRY

const BacklinkCache::CACHE_EXPIRY = 3600

private

Definition at line 96 of file BacklinkCache.php.

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

includes/cache/BacklinkCache.php

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Static Protected Attributes

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ __sleep()

◆ clear()

◆ get()

◆ getCascadeProtectedLinks()

◆ getConditions()

◆ getDB()

◆ getLinks()

◆ getNumLinks()

◆ getPrefix()

◆ hasLinks()

◆ makeCheckKey()

◆ partition()

◆ partitionResult()

◆ queryLinks()

◆ setDB()

Member Data Documentation

◆ $db

◆ $fullResultCache

◆ $instance

◆ $partitionCache

◆ $title

◆ $wanCache

◆ CACHE_EXPIRY