X-Git-Url: https://git.heureux-cyclage.org/?a=blobdiff_plain;f=includes%2FHTMLCacheUpdate.php;h=7c4731b0ad53805ea678042545bd8d4365b63e63;hb=42fe290d16f66ba3d719bc6149cc79570e55a6b3;hp=c678ecb81d0154a4446deca578d55731d5f1fa72;hpb=f0ff1cca9c426929d3be7e2613a11f0a8eb24412;p=lhc%2Fweb%2Fwiklou.git

diff --git a/includes/HTMLCacheUpdate.php b/includes/HTMLCacheUpdate.php
index c678ecb81d..7c4731b0ad 100644
--- a/includes/HTMLCacheUpdate.php
+++ b/includes/HTMLCacheUpdate.php
@@ -25,164 +25,188 @@
  */
 class HTMLCacheUpdate
 {
-	public $mTitle, $mTable, $mPrefix;
+	public $mTitle, $mTable, $mPrefix, $mStart, $mEnd;
 	public $mRowsPerJob, $mRowsPerQuery;
 
-	function __construct( $titleTo, $table ) {
+	function __construct( $titleTo, $table, $start = false, $end = false ) {
 		global $wgUpdateRowsPerJob, $wgUpdateRowsPerQuery;
 
 		$this->mTitle = $titleTo;
 		$this->mTable = $table;
+		$this->mStart = $start;
+		$this->mEnd = $end;
 		$this->mRowsPerJob = $wgUpdateRowsPerJob;
 		$this->mRowsPerQuery = $wgUpdateRowsPerQuery;
+		$this->mCache = $this->mTitle->getBacklinkCache();
 	}
 
 	public function doUpdate() {
-		# Fetch the IDs
-		$cond = $this->getToCondition();
-		$dbr = wfGetDB( DB_SLAVE );
-		$res = $dbr->select( $this->mTable, $this->getFromField(), $cond, __METHOD__ );
-
-		if ( $dbr->numRows( $res ) != 0 ) {
-			if ( $dbr->numRows( $res ) > $this->mRowsPerJob ) {
-				$this->insertJobs( $res );
+		if ( $this->mStart || $this->mEnd ) {
+			$this->doPartialUpdate();
+			return;
+		}
+
+		# Get an estimate of the number of rows from the BacklinkCache
+		$numRows = $this->mCache->getNumLinks( $this->mTable );
+		if ( $numRows > $this->mRowsPerJob * 2 ) {
+			# Do fast cached partition
+			$this->insertJobs();
+		} else {
+			# Get the links from the DB
+			$titleArray = $this->mCache->getLinks( $this->mTable );
+			# Check if the row count estimate was correct
+			if ( $titleArray->count() > $this->mRowsPerJob * 2 ) {
+				# Not correct, do accurate partition
+				wfDebug( __METHOD__.": row count estimate was incorrect, repartitioning\n" );
+				$this->insertJobsFromTitles( $titleArray );
 			} else {
-				$this->invalidateIDs( $res );
+				$this->invalidateTitles( $titleArray );
 			}
 		}
 		wfRunHooks( 'HTMLCacheUpdate::doUpdate', array($this->mTitle) );
 	}
 
-	protected function insertJobs( ResultWrapper $res ) {
-		$numRows = $res->numRows();
-		$numBatches = ceil( $numRows / $this->mRowsPerJob );
-		$realBatchSize = $numRows / $numBatches;
-		$start = false;
+	/**
+	 * Update some of the backlinks, defined by a page ID range
+	 */
+	protected function doPartialUpdate() {
+		$titleArray = $this->mCache->getLinks( $this->mTable, $this->mStart, $this->mEnd );
+		if ( $titleArray->count() <= $this->mRowsPerJob * 2 ) {
+			# This partition is small enough, do the update
+			$this->invalidateTitles( $titleArray );
+		} else {
+			# Partitioning was excessively inaccurate. Divide the job further.
+			# This can occur when a large number of links are added in a short 
+			# period of time, say by updating a heavily-used template.
+			$this->insertJobsFromTitles( $titleArray );
+		}
+	}
+
+	/**
+	 * Partition the current range given by $this->mStart and $this->mEnd,
+	 * using a pre-calculated title array which gives the links in that range.
+	 * Queue the resulting jobs.
+	 */
+	protected function insertJobsFromTitles( $titleArray ) {
+		# We make subpartitions in the sense that the start of the first job
+		# will be the start of the parent partition, and the end of the last
+		# job will be the end of the parent partition.
 		$jobs = array();
-		do {
-			for ( $i = 0; $i <= $realBatchSize - 1; $i++ ) {
-				$row = $res->fetchRow();
-				if ( $row ) {
-					$id = $row[0];
-				} else {
-					$id = false;
-					break;
-				}
+		$start = $this->mStart; # start of the current job
+		$numTitles = 0;
+		foreach ( $titleArray as $title ) {
+			$id = $title->getArticleID();
+			# $numTitles is now the number of titles in the current job not 
+			# including the current ID
+			if ( $numTitles >= $this->mRowsPerJob ) {
+				# Add a job up to but not including the current ID
+				$params = array(
+					'table' => $this->mTable,
+					'start' => $start,
+					'end' => $id - 1
+				);
+				$jobs[] = new HTMLCacheUpdateJob( $this->mTitle, $params );
+				$start = $id;
+				$numTitles = 0;
 			}
+			$numTitles++;
+		}
+		# Last job
+		$params = array(
+			'table' => $this->mTable,
+			'start' => $start,
+			'end' => $this->mEnd
+		);
+		$jobs[] = new HTMLCacheUpdateJob( $this->mTitle, $params );
+		wfDebug( __METHOD__.": repartitioning into " . count( $jobs ) . " jobs\n" );
+
+		if ( count( $jobs ) < 2 ) {
+			# I don't think this is possible at present, but handling this case
+			# makes the code a bit more robust against future code updates and 
+			# avoids a potential infinite loop of repartitioning
+			wfDebug( __METHOD__.": repartitioning failed!\n" );
+			$this->invalidateTitles( $titleArray );
+			return;
+		}
+
+		Job::batchInsert( $jobs );
+	}
 
+	protected function insertJobs() {
+		$batches = $this->mCache->partition( $this->mTable, $this->mRowsPerJob );
+		if ( !$batches ) {
+			return;
+		}
+		$jobs = array();
+		foreach ( $batches as $batch ) {
 			$params = array(
 				'table' => $this->mTable,
-				'start' => $start,
-				'end' => ( $id !== false ? $id - 1 : false ),
+				'start' => $batch[0],
+				'end' => $batch[1],
 			);
 			$jobs[] = new HTMLCacheUpdateJob( $this->mTitle, $params );
-
-			$start = $id;
-		} while ( $start );
-
-		Job::batchInsert( $jobs );
-	}
-
-	protected function getPrefix() {
-		static $prefixes = array(
-			'pagelinks' => 'pl',
-			'imagelinks' => 'il',
-			'categorylinks' => 'cl',
-			'templatelinks' => 'tl',
-			'redirect' => 'rd',
-		);
-
-		if ( is_null( $this->mPrefix ) ) {
-			$this->mPrefix = $prefixes[$this->mTable];
-			if ( is_null( $this->mPrefix ) ) {
-				throw new MWException( "Invalid table type \"{$this->mTable}\" in " . __CLASS__ );
-			}
 		}
-		return $this->mPrefix;
-	}
-
-	public function getFromField() {
-		return $this->getPrefix() . '_from';
+		Job::batchInsert( $jobs );
 	}
 
-	public function getToCondition() {
-		$prefix = $this->getPrefix();
-		switch ( $this->mTable ) {
-			case 'pagelinks':
-			case 'templatelinks':
-			case 'redirect':
-				return array(
-					"{$prefix}_namespace" => $this->mTitle->getNamespace(),
-					"{$prefix}_title" => $this->mTitle->getDBkey()
-				);
-			case 'imagelinks':
-				return array( 'il_to' => $this->mTitle->getDBkey() );
-			case 'categorylinks':
-				return array( 'cl_to' => $this->mTitle->getDBkey() );
-		}
-		throw new MWException( 'Invalid table type in ' . __CLASS__ );
+	/**
+	 * Invalidate a range of pages, right now
+	 * @deprecated
+	 */
+	public function invalidate( $startId = false, $endId = false ) {
+		$titleArray = $this->mCache->getLinks( $this->mTable, $startId, $endId );
+		$this->invalidateTitles( $titleArray );
 	}
 
 	/**
-	 * Invalidate a set of IDs, right now
+	 * Invalidate an array (or iterator) of Title objects, right now
 	 */
-	public function invalidateIDs( ResultWrapper $res ) {
+	protected function invalidateTitles( $titleArray ) {
 		global $wgUseFileCache, $wgUseSquid;
 
-		if ( $res->numRows() == 0 ) {
-			return;
-		}
-
 		$dbw = wfGetDB( DB_MASTER );
 		$timestamp = $dbw->timestamp();
-		$done = false;
-
-		while ( !$done ) {
-			# Get all IDs in this query into an array
-			$ids = array();
-			for ( $i = 0; $i < $this->mRowsPerQuery; $i++ ) {
-				$row = $res->fetchRow();
-				if ( $row ) {
-					$ids[] = $row[0];
-				} else {
-					$done = true;
-					break;
-				}
-			}
 
-			if ( !count( $ids ) ) {
-				break;
-			}
+		# Get all IDs in this query into an array
+		$ids = array();
+		foreach ( $titleArray as $title ) {
+			$ids[] = $title->getArticleID();
+		}
+
+		if ( !$ids ) {
+			return;
+		}
 
-			# Update page_touched
+		# Update page_touched
+		$batches = array_chunk( $ids, $this->mRowsPerQuery );
+		foreach ( $batches as $batch ) {
 			$dbw->update( 'page',
 				array( 'page_touched' => $timestamp ),
-				array( 'page_id IN (' . $dbw->makeList( $ids ) . ')' ),
+				array( 'page_id IN (' . $dbw->makeList( $batch ) . ')' ),
 				__METHOD__
 			);
+		}
+
+		# Update squid
+		if ( $wgUseSquid ) {
+			$u = SquidUpdate::newFromTitles( $titleArray );
+			$u->doUpdate();
+		}
 
-			# Update squid
-			if ( $wgUseSquid || $wgUseFileCache ) {
-				$titles = Title::newFromIDs( $ids );
-				if ( $wgUseSquid ) {
-					$u = SquidUpdate::newFromTitles( $titles );
-					$u->doUpdate();
-				}
-
-				# Update file cache
-				if  ( $wgUseFileCache ) {
-					foreach ( $titles as $title ) {
-						$cm = new HTMLFileCache($title);
-						@unlink($cm->fileCacheName());
-					}
-				}
+		# Update file cache
+		if  ( $wgUseFileCache ) {
+			foreach ( $titleArray as $title ) {
+				HTMLFileCache::clearFileCache( $title );
 			}
 		}
 	}
+
 }
 
 /**
- * @todo document (e.g. one-sentence top-level class description).
+ * Job wrapper for HTMLCacheUpdate. Gets run whenever a related
+ * job gets called from the queue.
+ * 
  * @ingroup JobQueue
  */
 class HTMLCacheUpdateJob extends Job {
@@ -202,21 +226,8 @@ class HTMLCacheUpdateJob extends Job {
 	}
 
 	public function run() {
-		$update = new HTMLCacheUpdate( $this->title, $this->table );
-
-		$fromField = $update->getFromField();
-		$conds = $update->getToCondition();
-		if ( $this->start ) {
-			$conds[] = "$fromField >= {$this->start}";
-		}
-		if ( $this->end ) {
-			$conds[] = "$fromField <= {$this->end}";
-		}
-
-		$dbr = wfGetDB( DB_SLAVE );
-		$res = $dbr->select( $this->table, $fromField, $conds, __METHOD__ );
-		$update->invalidateIDs( $res );
-
+		$update = new HTMLCacheUpdate( $this->title, $this->table, $this->start, $this->end );
+		$update->doUpdate();
 		return true;
 	}
 }