includes/parser/LinkHolderArray.php
<?php
/**
* Holder of replacement pairs for wiki links
*
* 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
* @ingroup Parser
*/
use MediaWiki\Cache\LinkCache;
use MediaWiki\HookContainer\HookContainer;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\Language\ILanguageConverter;
use MediaWiki\Linker\Linker;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Parser\Parser;
use MediaWiki\Parser\Sanitizer;
use MediaWiki\Title\Title;
/**
* @internal for using in Parser only.
*
* @ingroup Parser
*/
class LinkHolderArray {
/** @var array<int,array<int,array>> Indexed by numeric namespace and link ids, {@see Parser::nextLinkID} */
private $internals = [];
/** @var array<int,array> Indexed by numeric link id */
private $interwikis = [];
/** @var int */
private $size = 0;
/** @var Parser */
private $parent;
/** @var ILanguageConverter */
private $languageConverter;
/** @var HookRunner */
private $hookRunner;
/**
* @param Parser $parent
* @param ILanguageConverter $languageConverter
* @param HookContainer $hookContainer
*/
public function __construct( Parser $parent, ILanguageConverter $languageConverter,
HookContainer $hookContainer
) {
$this->parent = $parent;
$this->languageConverter = $languageConverter;
$this->hookRunner = new HookRunner( $hookContainer );
}
/**
* Reduce memory usage to reduce the impact of circular references
*/
public function __destruct() {
// @phan-suppress-next-line PhanTypeSuspiciousNonTraversableForeach
foreach ( $this as $name => $_ ) {
unset( $this->$name );
}
}
/**
* Merge another LinkHolderArray into this one
* @param LinkHolderArray $other
*/
public function merge( $other ) {
foreach ( $other->internals as $ns => $entries ) {
$this->size += count( $entries );
if ( !isset( $this->internals[$ns] ) ) {
$this->internals[$ns] = $entries;
} else {
$this->internals[$ns] += $entries;
}
}
$this->interwikis += $other->interwikis;
}
/**
* Returns true if the memory requirements of this object are getting large
* @return bool
*/
public function isBig() {
$linkHolderBatchSize = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::LinkHolderBatchSize );
return $this->size > $linkHolderBatchSize;
}
/**
* Clear all stored link holders.
* Make sure you don't have any text left using these link holders, before you call this
*/
public function clear() {
$this->internals = [];
$this->interwikis = [];
$this->size = 0;
}
/**
* Make a link placeholder. The text returned can be later resolved to a real link with
* replaceLinkHolders(). This is done for two reasons: firstly to avoid further
* parsing of interwiki links, and secondly to allow all existence checks and
* article length checks (for stub links) to be bundled into a single query.
*
* @param Title $nt
* @param string $text
* @param string $trail [optional]
* @param string $prefix [optional]
* @return string
*/
public function makeHolder( Title $nt, $text = '', $trail = '', $prefix = '' ) {
# Separate the link trail from the rest of the link
[ $inside, $trail ] = Linker::splitTrail( $trail );
$key = $this->parent->nextLinkID();
$entry = [
'title' => $nt,
'text' => $prefix . $text . $inside,
'pdbk' => $nt->getPrefixedDBkey(),
];
$this->size++;
if ( $nt->isExternal() ) {
// Use a globally unique ID to keep the objects mergable
$this->interwikis[$key] = $entry;
return "<!--IWLINK'\" $key-->{$trail}";
} else {
$ns = $nt->getNamespace();
$this->internals[$ns][$key] = $entry;
return "<!--LINK'\" $ns:$key-->{$trail}";
}
}
/**
* Replace <!--LINK--> link placeholders with actual links, in the buffer
*
* @param string &$text
*/
public function replace( &$text ) {
$this->replaceInternal( $text );
$this->replaceInterwiki( $text );
}
/**
* Replace internal links
* @param string &$text
*/
protected function replaceInternal( &$text ) {
if ( !$this->internals ) {
return;
}
$classes = [];
$services = MediaWikiServices::getInstance();
$linkCache = $services->getLinkCache();
$output = $this->parent->getOutput();
$linkRenderer = $this->parent->getLinkRenderer();
$dbr = $services->getConnectionProvider()->getReplicaDatabase();
# Sort by namespace
ksort( $this->internals );
$pagemap = [];
# Generate query
$linkBatchFactory = $services->getLinkBatchFactory();
$lb = $linkBatchFactory->newLinkBatch();
$lb->setCaller( __METHOD__ );
foreach ( $this->internals as $ns => $entries ) {
foreach ( $entries as [ 'title' => $title, 'pdbk' => $pdbk ] ) {
/** @var Title $title */
# Check if it's a static known link, e.g. interwiki
if ( $title->isAlwaysKnown() ) {
$classes[$pdbk] = '';
} elseif ( $ns === NS_SPECIAL ) {
$classes[$pdbk] = 'new';
} else {
$id = $linkCache->getGoodLinkID( $pdbk );
if ( $id ) {
$classes[$pdbk] = $linkRenderer->getLinkClasses( $title );
$output->addLink( $title, $id );
$pagemap[$id] = $pdbk;
} elseif ( $linkCache->isBadLink( $pdbk ) ) {
$classes[$pdbk] = 'new';
} else {
# Not in the link cache, add it to the query
$lb->addObj( $title );
}
}
}
}
if ( !$lb->isEmpty() ) {
$res = $dbr->newSelectQueryBuilder()
->select( LinkCache::getSelectFields() )
->from( 'page' )
->where( [ $lb->constructSet( 'page', $dbr ) ] )
->caller( __METHOD__ )
->fetchResultSet();
# Fetch data and form into an associative array
# non-existent = broken
foreach ( $res as $s ) {
$title = Title::makeTitle( $s->page_namespace, $s->page_title );
$pdbk = $title->getPrefixedDBkey();
$linkCache->addGoodLinkObjFromRow( $title, $s );
$output->addLink( $title, $s->page_id );
$classes[$pdbk] = $linkRenderer->getLinkClasses( $title );
// add id to the extension todolist
$pagemap[$s->page_id] = $pdbk;
}
unset( $res );
}
if ( $pagemap !== [] ) {
// pass an array of page_ids to an extension
$this->hookRunner->onGetLinkColours( $pagemap, $classes, $this->parent->getTitle() );
}
# Do a second query for different language variants of links and categories
if ( $this->languageConverter->hasVariants() ) {
$this->doVariants( $classes );
}
# Construct search and replace arrays
$replacePairs = [];
foreach ( $this->internals as $ns => $entries ) {
foreach ( $entries as $index => $entry ) {
$pdbk = $entry['pdbk'];
$title = $entry['title'];
$query = $entry['query'] ?? [];
$searchkey = "$ns:$index";
$displayTextHtml = $entry['text'];
if ( isset( $entry['selflink'] ) ) {
$replacePairs[$searchkey] = Linker::makeSelfLinkObj(
$title, $displayTextHtml, $query, '', '',
Sanitizer::escapeIdForLink( $title->getFragment() )
);
continue;
}
$displayText = $displayTextHtml === '' ? null : new HtmlArmor( $displayTextHtml );
if ( !isset( $classes[$pdbk] ) ) {
$classes[$pdbk] = 'new';
}
if ( $classes[$pdbk] === 'new' ) {
$linkCache->addBadLinkObj( $title );
$output->addLink( $title, 0 );
$link = $linkRenderer->makeBrokenLink(
$title, $displayText, [], $query
);
} else {
$link = $linkRenderer->makePreloadedLink(
$title, $displayText, $classes[$pdbk], [], $query
);
}
$replacePairs[$searchkey] = $link;
}
}
# Do the thing
$text = preg_replace_callback(
'/<!--LINK\'" (-?[\d:]+)-->/',
static function ( array $matches ) use ( $replacePairs ) {
return $replacePairs[$matches[1]];
},
$text
);
}
/**
* Replace interwiki links
* @param string &$text
*/
protected function replaceInterwiki( &$text ) {
if ( !$this->interwikis ) {
return;
}
# Make interwiki link HTML
$output = $this->parent->getOutput();
$replacePairs = [];
$linkRenderer = $this->parent->getLinkRenderer();
foreach ( $this->interwikis as $key => [ 'title' => $title, 'text' => $linkText ] ) {
$replacePairs[$key] = $linkRenderer->makeLink( $title, new HtmlArmor( $linkText ) );
$output->addInterwikiLink( $title );
}
$text = preg_replace_callback(
'/<!--IWLINK\'" (\d+)-->/',
static function ( array $matches ) use ( $replacePairs ) {
return $replacePairs[$matches[1]];
},
$text
);
}
/**
* Modify $this->internals and $classes according to language variant linking rules
* @param string[] &$classes
*/
protected function doVariants( &$classes ) {
$linkBatchFactory = MediaWikiServices::getInstance()->getLinkBatchFactory();
$linkBatch = $linkBatchFactory->newLinkBatch();
$variantMap = []; // maps $pdbkey_Variant => $keys (of link holders)
$output = $this->parent->getOutput();
$titlesToBeConverted = '';
$titlesAttrs = [];
// Concatenate titles to a single string, thus we only need auto convert the
// single string to all variants. This would improve parser's performance
// significantly.
foreach ( $this->internals as $ns => $entries ) {
if ( $ns === NS_SPECIAL ) {
continue;
}
foreach ( $entries as $index => [ 'title' => $title, 'pdbk' => $pdbk ] ) {
// we only deal with new links (in its first query)
if ( !isset( $classes[$pdbk] ) || $classes[$pdbk] === 'new' ) {
$titlesAttrs[] = [ $index, $title ];
// separate titles with \0 because it would never appears
// in a valid title
$titlesToBeConverted .= $title->getText() . "\0";
}
}
}
// Now do the conversion and explode string to text of titles
$titlesAllVariants = $this->languageConverter->
autoConvertToAllVariants( rtrim( $titlesToBeConverted, "\0" ) );
foreach ( $titlesAllVariants as &$titlesVariant ) {
$titlesVariant = explode( "\0", $titlesVariant );
}
// Then add variants of links to link batch
$parentTitle = $this->parent->getTitle();
foreach ( $titlesAttrs as $i => [ $index, $title ] ) {
/** @var Title $title */
$ns = $title->getNamespace();
$text = $title->getText();
foreach ( $titlesAllVariants as $textVariants ) {
$textVariant = $textVariants[$i];
if ( $textVariant === $text ) {
continue;
}
$variantTitle = Title::makeTitle( $ns, $textVariant );
// Self-link checking for mixed/different variant titles. At this point, we
// already know the exact title does not exist, so the link cannot be to a
// variant of the current title that exists as a separate page.
if ( $variantTitle->equals( $parentTitle ) ) {
$this->internals[$ns][$index]['selflink'] = true;
continue 2;
}
$linkBatch->addObj( $variantTitle );
$variantMap[$variantTitle->getPrefixedDBkey()][] = "$ns:$index";
}
}
// process categories, check if a category exists in some variant
$categoryMap = []; // maps $category_variant => $category (dbkeys)
foreach ( $output->getCategoryNames() as $category ) {
$categoryTitle = Title::makeTitleSafe( NS_CATEGORY, $category );
$linkBatch->addObj( $categoryTitle );
$variants = $this->languageConverter->autoConvertToAllVariants( $category );
foreach ( $variants as $variant ) {
if ( $variant !== $category ) {
$variantTitle = Title::makeTitleSafe( NS_CATEGORY, $variant );
if ( $variantTitle ) {
$linkBatch->addObj( $variantTitle );
$categoryMap[$variant] = [ $category, $categoryTitle ];
}
}
}
}
if ( $linkBatch->isEmpty() ) {
return;
}
// construct query
$dbr = MediaWikiServices::getInstance()->getConnectionProvider()->getReplicaDatabase();
$varRes = $dbr->newSelectQueryBuilder()
->select( LinkCache::getSelectFields() )
->from( 'page' )
->where( [ $linkBatch->constructSet( 'page', $dbr ) ] )
->caller( __METHOD__ )
->fetchResultSet();
$pagemap = [];
$varCategories = [];
$linkCache = MediaWikiServices::getInstance()->getLinkCache();
$linkRenderer = $this->parent->getLinkRenderer();
// for each found variants, figure out link holders and replace
foreach ( $varRes as $s ) {
$variantTitle = Title::makeTitle( $s->page_namespace, $s->page_title );
$varPdbk = $variantTitle->getPrefixedDBkey();
if ( !isset( $variantMap[$varPdbk] ) ) {
continue;
}
$linkCache->addGoodLinkObjFromRow( $variantTitle, $s );
$output->addLink( $variantTitle, $s->page_id );
// loop over link holders
foreach ( $variantMap[$varPdbk] as $key ) {
[ $ns, $index ] = explode( ':', $key, 2 );
$entry =& $this->internals[(int)$ns][(int)$index];
// The selflink we marked above might not have been the first
// $textVariants so be sure to skip any entries that have
// subsequently been marked.
if ( isset( $entry['selflink'] ) ) {
continue;
}
$pdbk = $entry['pdbk'];
if ( !isset( $classes[$pdbk] ) || $classes[$pdbk] === 'new' ) {
// found link in some of the variants, replace the link holder data
$entry['title'] = $variantTitle;
$entry['pdbk'] = $varPdbk;
// set pdbk and colour if we haven't checked this title yet.
if ( !isset( $classes[$varPdbk] ) ) {
$classes[$varPdbk] = $linkRenderer->getLinkClasses( $variantTitle );
$pagemap[$s->page_id] = $varPdbk;
}
}
}
// check if the object is a variant of a category
$vardbk = $variantTitle->getDBkey();
if ( isset( $categoryMap[$vardbk] ) ) {
[ $oldkey, $oldtitle ] = $categoryMap[$vardbk];
if ( !isset( $varCategories[$oldkey] ) && !$oldtitle->exists() ) {
$varCategories[$oldkey] = $vardbk;
}
}
}
$this->hookRunner->onGetLinkColours( $pagemap, $classes, $this->parent->getTitle() );
// rebuild the categories in original order (if there are replacements)
if ( $varCategories !== [] ) {
$newCats = [];
foreach ( $output->getCategoryNames() as $cat ) {
$sortkey = $output->getCategorySortKey( $cat );
// make the replacement
$newCats[$varCategories[$cat] ?? $cat] = $sortkey;
}
$output->setCategories( $newCats );
}
}
/**
* Replace <!--LINK'" …--> and <!--IWLINK'" …--> link placeholders with plain text of links
* (not HTML-formatted).
*
* @param string $text
* @return string
*/
public function replaceText( $text ) {
return preg_replace_callback(
'/<!--(IW)?LINK\'" (-?[\d:]+)-->/',
function ( $matches ) {
[ $unchanged, $isInterwiki, $key ] = $matches;
if ( !$isInterwiki ) {
[ $ns, $index ] = explode( ':', $key, 2 );
return $this->internals[(int)$ns][(int)$index]['text'] ?? $unchanged;
} else {
return $this->interwikis[$key]['text'] ?? $unchanged;
}
},
$text
);
}
}