diff options
Diffstat (limited to 'includes/LinksUpdate.php')
| -rw-r--r-- | includes/LinksUpdate.php | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/includes/LinksUpdate.php b/includes/LinksUpdate.php new file mode 100644 index 00000000..9e25bf07 --- /dev/null +++ b/includes/LinksUpdate.php @@ -0,0 +1,601 @@ +<?php +/** + * See deferred.txt + * @package MediaWiki + */ + +/** + * @todo document + * @package MediaWiki + */ +class LinksUpdate { + + /**@{{ + * @private + */ + var $mId, //!< Page ID of the article linked from + $mTitle, //!< Title object of the article linked from + $mLinks, //!< Map of title strings to IDs for the links in the document + $mImages, //!< DB keys of the images used, in the array key only + $mTemplates, //!< Map of title strings to IDs for the template references, including broken ones + $mExternals, //!< URLs of external links, array key only + $mCategories, //!< Map of category names to sort keys + $mInterlangs, //!< Map of language codes to titles + $mDb, //!< Database connection reference + $mOptions, //!< SELECT options to be used (array) + $mRecursive; //!< Whether to queue jobs for recursive updates + /**@}}*/ + + /** + * Constructor + * Initialize private variables + * @param $title Integer: FIXME + * @param $parserOutput FIXME + * @param $recursive Boolean: FIXME, default 'true'. + */ + function LinksUpdate( $title, $parserOutput, $recursive = true ) { + global $wgAntiLockFlags; + + if ( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) { + $this->mOptions = array(); + } else { + $this->mOptions = array( 'FOR UPDATE' ); + } + $this->mDb =& wfGetDB( DB_MASTER ); + + if ( !is_object( $title ) ) { + throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " . + "Please see Article::editUpdates() for an invocation example.\n" ); + } + $this->mTitle = $title; + $this->mId = $title->getArticleID(); + + $this->mLinks = $parserOutput->getLinks(); + $this->mImages = $parserOutput->getImages(); + $this->mTemplates = $parserOutput->getTemplates(); + $this->mExternals = $parserOutput->getExternalLinks(); + $this->mCategories = $parserOutput->getCategories(); + + # Convert the format of the interlanguage links + # I didn't want to change it in the ParserOutput, because that array is passed all + # the way back to the skin, so either a skin API break would be required, or an + # inefficient back-conversion. + $ill = $parserOutput->getLanguageLinks(); + $this->mInterlangs = array(); + foreach ( $ill as $link ) { + list( $key, $title ) = explode( ':', $link, 2 ); + $this->mInterlangs[$key] = $title; + } + + $this->mRecursive = $recursive; + } + + /** + * Update link tables with outgoing links from an updated article + */ + function doUpdate() { + global $wgUseDumbLinkUpdate; + if ( $wgUseDumbLinkUpdate ) { + $this->doDumbUpdate(); + } else { + $this->doIncrementalUpdate(); + } + } + + function doIncrementalUpdate() { + $fname = 'LinksUpdate::doIncrementalUpdate'; + wfProfileIn( $fname ); + + # Page links + $existing = $this->getExistingLinks(); + $this->incrTableUpdate( 'pagelinks', 'pl', $this->getLinkDeletions( $existing ), + $this->getLinkInsertions( $existing ) ); + + # Image links + $existing = $this->getExistingImages(); + $this->incrTableUpdate( 'imagelinks', 'il', $this->getImageDeletions( $existing ), + $this->getImageInsertions( $existing ) ); + + # Invalidate all image description pages which had links added or removed + $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing ); + $this->invalidateImageDescriptions( $imageUpdates ); + + # External links + $existing = $this->getExistingExternals(); + $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ), + $this->getExternalInsertions( $existing ) ); + + # Language links + $existing = $this->getExistingInterlangs(); + $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ), + $this->getInterlangInsertions( $existing ) ); + + # Template links + $existing = $this->getExistingTemplates(); + $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ), + $this->getTemplateInsertions( $existing ) ); + + # Category links + $existing = $this->getExistingCategories(); + $this->incrTableUpdate( 'categorylinks', 'cl', $this->getCategoryDeletions( $existing ), + $this->getCategoryInsertions( $existing ) ); + + # Invalidate all categories which were added, deleted or changed (set symmetric difference) + $categoryUpdates = array_diff_assoc( $existing, $this->mCategories ) + array_diff_assoc( $this->mCategories, $existing ); + $this->invalidateCategories( $categoryUpdates ); + + # Refresh links of all pages including this page + # This will be in a separate transaction + if ( $this->mRecursive ) { + $this->queueRecursiveJobs(); + } + + wfProfileOut( $fname ); + } + + /** + * Link update which clears the previous entries and inserts new ones + * May be slower or faster depending on level of lock contention and write speed of DB + * Also useful where link table corruption needs to be repaired, e.g. in refreshLinks.php + */ + function doDumbUpdate() { + $fname = 'LinksUpdate::doDumbUpdate'; + wfProfileIn( $fname ); + + # Refresh category pages and image description pages + $existing = $this->getExistingCategories(); + $categoryUpdates = array_diff_assoc( $existing, $this->mCategories ) + array_diff_assoc( $this->mCategories, $existing ); + $existing = $this->getExistingImages(); + $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing ); + + $this->dumbTableUpdate( 'pagelinks', $this->getLinkInsertions(), 'pl_from' ); + $this->dumbTableUpdate( 'imagelinks', $this->getImageInsertions(), 'il_from' ); + $this->dumbTableUpdate( 'categorylinks', $this->getCategoryInsertions(), 'cl_from' ); + $this->dumbTableUpdate( 'templatelinks', $this->getTemplateInsertions(), 'tl_from' ); + $this->dumbTableUpdate( 'externallinks', $this->getExternalInsertions(), 'el_from' ); + $this->dumbTableUpdate( 'langlinks', $this->getInterlangInsertions(), 'll_from' ); + + # Update the cache of all the category pages and image description pages which were changed + $this->invalidateCategories( $categoryUpdates ); + $this->invalidateImageDescriptions( $imageUpdates ); + + # Refresh links of all pages including this page + # This will be in a separate transaction + if ( $this->mRecursive ) { + $this->queueRecursiveJobs(); + } + + wfProfileOut( $fname ); + } + + function queueRecursiveJobs() { + wfProfileIn( __METHOD__ ); + + $batchSize = 100; + $dbr =& wfGetDB( DB_SLAVE ); + $res = $dbr->select( array( 'templatelinks', 'page' ), + array( 'page_namespace', 'page_title' ), + array( + 'page_id=tl_from', + 'tl_namespace' => $this->mTitle->getNamespace(), + 'tl_title' => $this->mTitle->getDBkey() + ), __METHOD__ + ); + + $done = false; + while ( !$done ) { + $jobs = array(); + for ( $i = 0; $i < $batchSize; $i++ ) { + $row = $dbr->fetchObject( $res ); + if ( !$row ) { + $done = true; + break; + } + $title = Title::makeTitle( $row->page_namespace, $row->page_title ); + $jobs[] = Job::factory( 'refreshLinks', $title ); + } + Job::batchInsert( $jobs ); + } + $dbr->freeResult( $res ); + wfProfileOut( __METHOD__ ); + } + + /** + * Invalidate the cache of a list of pages from a single namespace + * + * @param integer $namespace + * @param array $dbkeys + */ + function invalidatePages( $namespace, $dbkeys ) { + $fname = 'LinksUpdate::invalidatePages'; + + if ( !count( $dbkeys ) ) { + return; + } + + /** + * Determine which pages need to be updated + * This is necessary to prevent the job queue from smashing the DB with + * large numbers of concurrent invalidations of the same page + */ + $now = $this->mDb->timestamp(); + $ids = array(); + $res = $this->mDb->select( 'page', array( 'page_id' ), + array( + 'page_namespace' => $namespace, + 'page_title IN (' . $this->mDb->makeList( $dbkeys ) . ')', + 'page_touched < ' . $this->mDb->addQuotes( $now ) + ), $fname + ); + while ( $row = $this->mDb->fetchObject( $res ) ) { + $ids[] = $row->page_id; + } + if ( !count( $ids ) ) { + return; + } + + /** + * Do the update + * We still need the page_touched condition, in case the row has changed since + * the non-locking select above. + */ + $this->mDb->update( 'page', array( 'page_touched' => $now ), + array( + 'page_id IN (' . $this->mDb->makeList( $ids ) . ')', + 'page_touched < ' . $this->mDb->addQuotes( $now ) + ), $fname + ); + } + + function invalidateCategories( $cats ) { + $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) ); + } + + function invalidateImageDescriptions( $images ) { + $this->invalidatePages( NS_IMAGE, array_keys( $images ) ); + } + + function dumbTableUpdate( $table, $insertions, $fromField ) { + $fname = 'LinksUpdate::dumbTableUpdate'; + $this->mDb->delete( $table, array( $fromField => $this->mId ), $fname ); + if ( count( $insertions ) ) { + # The link array was constructed without FOR UPDATE, so there may be collisions + # This may cause minor link table inconsistencies, which is better than + # crippling the site with lock contention. + $this->mDb->insert( $table, $insertions, $fname, array( 'IGNORE' ) ); + } + } + + /** + * Make a WHERE clause from a 2-d NS/dbkey array + * + * @param array $arr 2-d array indexed by namespace and DB key + * @param string $prefix Field name prefix, without the underscore + */ + function makeWhereFrom2d( &$arr, $prefix ) { + $lb = new LinkBatch; + $lb->setArray( $arr ); + return $lb->constructSet( $prefix, $this->mDb ); + } + + /** + * Update a table by doing a delete query then an insert query + * @private + */ + function incrTableUpdate( $table, $prefix, $deletions, $insertions ) { + $fname = 'LinksUpdate::incrTableUpdate'; + $where = array( "{$prefix}_from" => $this->mId ); + if ( $table == 'pagelinks' || $table == 'templatelinks' ) { + $clause = $this->makeWhereFrom2d( $deletions, $prefix ); + if ( $clause ) { + $where[] = $clause; + } else { + $where = false; + } + } else { + if ( $table == 'langlinks' ) { + $toField = 'll_lang'; + } else { + $toField = $prefix . '_to'; + } + if ( count( $deletions ) ) { + $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')'; + } else { + $where = false; + } + } + if ( $where ) { + $this->mDb->delete( $table, $where, $fname ); + } + if ( count( $insertions ) ) { + $this->mDb->insert( $table, $insertions, $fname, 'IGNORE' ); + } + } + + + /** + * Get an array of pagelinks insertions for passing to the DB + * Skips the titles specified by the 2-D array $existing + * @private + */ + function getLinkInsertions( $existing = array() ) { + $arr = array(); + foreach( $this->mLinks as $ns => $dbkeys ) { + # array_diff_key() was introduced in PHP 5.1, there is a compatibility function + # in GlobalFunctions.php + $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys; + foreach ( $diffs as $dbk => $id ) { + $arr[] = array( + 'pl_from' => $this->mId, + 'pl_namespace' => $ns, + 'pl_title' => $dbk + ); + } + } + return $arr; + } + + /** + * Get an array of template insertions. Like getLinkInsertions() + * @private + */ + function getTemplateInsertions( $existing = array() ) { + $arr = array(); + foreach( $this->mTemplates as $ns => $dbkeys ) { + $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys; + foreach ( $diffs as $dbk => $id ) { + $arr[] = array( + 'tl_from' => $this->mId, + 'tl_namespace' => $ns, + 'tl_title' => $dbk + ); + } + } + return $arr; + } + + /** + * Get an array of image insertions + * Skips the names specified in $existing + * @private + */ + function getImageInsertions( $existing = array() ) { + $arr = array(); + $diffs = array_diff_key( $this->mImages, $existing ); + foreach( $diffs as $iname => $dummy ) { + $arr[] = array( + 'il_from' => $this->mId, + 'il_to' => $iname + ); + } + return $arr; + } + + /** + * Get an array of externallinks insertions. Skips the names specified in $existing + * @private + */ + function getExternalInsertions( $existing = array() ) { + $arr = array(); + $diffs = array_diff_key( $this->mExternals, $existing ); + foreach( $diffs as $url => $dummy ) { + $arr[] = array( + 'el_from' => $this->mId, + 'el_to' => $url, + 'el_index' => wfMakeUrlIndex( $url ), + ); + } + return $arr; + } + + /** + * Get an array of category insertions + * @param array $existing Array mapping existing category names to sort keys. If both + * match a link in $this, the link will be omitted from the output + * @private + */ + function getCategoryInsertions( $existing = array() ) { + $diffs = array_diff_assoc( $this->mCategories, $existing ); + $arr = array(); + foreach ( $diffs as $name => $sortkey ) { + $arr[] = array( + 'cl_from' => $this->mId, + 'cl_to' => $name, + 'cl_sortkey' => $sortkey, + 'cl_timestamp' => $this->mDb->timestamp() + ); + } + return $arr; + } + + /** + * Get an array of interlanguage link insertions + * @param array $existing Array mapping existing language codes to titles + * @private + */ + function getInterlangInsertions( $existing = array() ) { + $diffs = array_diff_assoc( $this->mInterlangs, $existing ); + $arr = array(); + foreach( $diffs as $lang => $title ) { + $arr[] = array( + 'll_from' => $this->mId, + 'll_lang' => $lang, + 'll_title' => $title + ); + } + return $arr; + } + + /** + * Given an array of existing links, returns those links which are not in $this + * and thus should be deleted. + * @private + */ + function getLinkDeletions( $existing ) { + $del = array(); + foreach ( $existing as $ns => $dbkeys ) { + if ( isset( $this->mLinks[$ns] ) ) { + $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] ); + } else { + $del[$ns] = $existing[$ns]; + } + } + return $del; + } + + /** + * Given an array of existing templates, returns those templates which are not in $this + * and thus should be deleted. + * @private + */ + function getTemplateDeletions( $existing ) { + $del = array(); + foreach ( $existing as $ns => $dbkeys ) { + if ( isset( $this->mTemplates[$ns] ) ) { + $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] ); + } else { + $del[$ns] = $existing[$ns]; + } + } + return $del; + } + + /** + * Given an array of existing images, returns those images which are not in $this + * and thus should be deleted. + * @private + */ + function getImageDeletions( $existing ) { + return array_diff_key( $existing, $this->mImages ); + } + + /** + * Given an array of existing external links, returns those links which are not + * in $this and thus should be deleted. + * @private + */ + function getExternalDeletions( $existing ) { + return array_diff_key( $existing, $this->mExternals ); + } + + /** + * Given an array of existing categories, returns those categories which are not in $this + * and thus should be deleted. + * @private + */ + function getCategoryDeletions( $existing ) { + return array_diff_assoc( $existing, $this->mCategories ); + } + + /** + * Given an array of existing interlanguage links, returns those links which are not + * in $this and thus should be deleted. + * @private + */ + function getInterlangDeletions( $existing ) { + return array_diff_assoc( $existing, $this->mInterlangs ); + } + + /** + * Get an array of existing links, as a 2-D array + * @private + */ + function getExistingLinks() { + $fname = 'LinksUpdate::getExistingLinks'; + $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ), + array( 'pl_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + if ( !isset( $arr[$row->pl_namespace] ) ) { + $arr[$row->pl_namespace] = array(); + } + $arr[$row->pl_namespace][$row->pl_title] = 1; + } + $this->mDb->freeResult( $res ); + return $arr; + } + + /** + * Get an array of existing templates, as a 2-D array + * @private + */ + function getExistingTemplates() { + $fname = 'LinksUpdate::getExistingTemplates'; + $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ), + array( 'tl_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + if ( !isset( $arr[$row->tl_namespace] ) ) { + $arr[$row->tl_namespace] = array(); + } + $arr[$row->tl_namespace][$row->tl_title] = 1; + } + $this->mDb->freeResult( $res ); + return $arr; + } + + /** + * Get an array of existing images, image names in the keys + * @private + */ + function getExistingImages() { + $fname = 'LinksUpdate::getExistingImages'; + $res = $this->mDb->select( 'imagelinks', array( 'il_to' ), + array( 'il_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + $arr[$row->il_to] = 1; + } + $this->mDb->freeResult( $res ); + return $arr; + } + + /** + * Get an array of existing external links, URLs in the keys + * @private + */ + function getExistingExternals() { + $fname = 'LinksUpdate::getExistingExternals'; + $res = $this->mDb->select( 'externallinks', array( 'el_to' ), + array( 'el_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + $arr[$row->el_to] = 1; + } + $this->mDb->freeResult( $res ); + return $arr; + } + + /** + * Get an array of existing categories, with the name in the key and sort key in the value. + * @private + */ + function getExistingCategories() { + $fname = 'LinksUpdate::getExistingCategories'; + $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey' ), + array( 'cl_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + $arr[$row->cl_to] = $row->cl_sortkey; + } + $this->mDb->freeResult( $res ); + return $arr; + } + + /** + * Get an array of existing interlanguage links, with the language code in the key and the + * title in the value. + * @private + */ + function getExistingInterlangs() { + $fname = 'LinksUpdate::getExistingInterlangs'; + $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ), + array( 'll_from' => $this->mId ), $fname, $this->mOptions ); + $arr = array(); + while ( $row = $this->mDb->fetchObject( $res ) ) { + $arr[$row->ll_lang] = $row->ll_title; + } + return $arr; + } +} +?> |