<?php
/**
- * File for BacklinkCache class
+ * Class for fetching backlink lists, approximate backlink counts and
+ * partitions.
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
* @file
+ * @author Tim Starling
+ * @copyright © 2009, Tim Starling, Domas Mituzas
+ * @copyright © 2010, Max Sem
+ * @copyright © 2011, Antoine Musso
*/
/**
* Introduced by r47317
*
* @internal documentation reviewed on 18 Mar 2011 by hashar
- *
- * @author Tim Starling
- * @copyright © 2009, Tim Starling, Domas Mituzas
- * @copyright © 2010, Max Sem
- * @copyright © 2011, Ashar Voultoiz
*/
class BacklinkCache {
+ /** @var ProcessCacheLRU */
+ protected static $cache;
/**
* Multi dimensions array representing batches. Keys are:
/**
* Create a new BacklinkCache
- * @param Title $title : Title object to create a backlink cache for.
+ *
+ * @param Title $title : Title object to create a backlink cache for
*/
- function __construct( $title ) {
+ public function __construct( Title $title ) {
$this->title = $title;
}
+ /**
+ * 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.
+ *
+ * @param Title $title : Title object to get a backlink cache for
+ * @return BacklinkCache
+ */
+ public static function get( Title $title ) {
+ if ( !self::$cache ) { // init cache
+ self::$cache = new ProcessCacheLRU( 1 );
+ }
+ $dbKey = $title->getPrefixedDBkey();
+ if ( !self::$cache->has( $dbKey, 'obj' ) ) {
+ self::$cache->set( $dbKey, 'obj', new self( $title ) );
+ }
+ return self::$cache->get( $dbKey, 'obj' );
+ }
+
/**
* Serialization handler, diasallows to serialize the database to prevent
* failures after this class is deserialized from cache with dead DB
* connection.
+ *
+ * @return array
*/
function __sleep() {
return array( 'partitionCache', 'fullResultCache', 'title' );
/**
* Get the slave connection to the database
* When non existing, will initialize the connection.
- * @return Database object
+ * @return DatabaseBase object
*/
protected function getDB() {
if ( !isset( $this->db ) ) {
/**
* Get the field name prefix for a given table
* @param $table String
+ * @return null|string
*/
protected function getPrefix( $table ) {
static $prefixes = array(
if ( isset( $prefixes[$table] ) ) {
return $prefixes[$table];
} else {
- throw new MWException( "Invalid table \"$table\" in " . __CLASS__ );
+ $prefix = null;
+ wfRunHooks( 'BacklinkCacheGetPrefix', array( $table, &$prefix ) );
+ if( $prefix ) {
+ return $prefix;
+ } else {
+ throw new MWException( "Invalid table \"$table\" in " . __CLASS__ );
+ }
}
}
* Get the SQL condition array for selecting backlinks, with a join
* on the page table.
* @param $table String
+ * @return array|null
*/
protected function getConditions( $table ) {
$prefix = $this->getPrefix( $table );
switch ( $table ) {
case 'pagelinks':
case 'templatelinks':
+ $conds = array(
+ "{$prefix}_namespace" => $this->title->getNamespace(),
+ "{$prefix}_title" => $this->title->getDBkey(),
+ "page_id={$prefix}_from"
+ );
+ break;
case 'redirect':
$conds = array(
"{$prefix}_namespace" => $this->title->getNamespace(),
"{$prefix}_title" => $this->title->getDBkey(),
+ $this->getDb()->makeList( array(
+ "{$prefix}_interwiki = ''",
+ "{$prefix}_interwiki is null",
+ ), LIST_OR ),
"page_id={$prefix}_from"
);
break;
);
break;
default:
- throw new MWException( "Invalid table \"$table\" in " . __CLASS__ );
+ $conds = null;
+ wfRunHooks( 'BacklinkCacheGetConditions', array( $table, $this->title, &$conds ) );
+ if( !$conds )
+ throw new MWException( "Invalid table \"$table\" in " . __CLASS__ );
}
return $conds;
/**
* Partition the backlinks into batches.
- * Returns an array giving the start and end of each range. The firsti
+ * 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.
*
* @param $table String: the links table name
*/
public function partition( $table, $batchSize ) {
- // 1) try this per process cache first
+ // 1) try partition cache ...
if ( isset( $this->partitionCache[$table][$batchSize] ) ) {
wfDebug( __METHOD__ . ": got from partition cache\n" );
$this->partitionCache[$table][$batchSize] = false;
$cacheEntry =& $this->partitionCache[$table][$batchSize];
- // 2) try full result cache
+ // 2) ... then try full result cache ...
if ( isset( $this->fullResultCache[$table] ) ) {
$cacheEntry = $this->partitionResult( $this->fullResultCache[$table], $batchSize );
* Partition a DB result with backlinks in it into batches
* @param $res ResultWrapper database result
* @param $batchSize integer
- * @return array @see
+ * @return array @see
*/
protected function partitionResult( $res, $batchSize ) {
$batches = array();
dépôts / lhc / web / wiklou.git / blobdiff