X-Git-Url: https://git.heureux-cyclage.org/?a=blobdiff_plain;f=includes%2FJobQueue.php;h=afa757d752ed84f34e1ee6fe777c4edd6dc6059c;hb=4124558d7b40df818337f1d7eeae10c9ee9688e2;hp=3eddd50e7fd3649fc1c6169e9abcffef5ac6a212;hpb=6c5d3c8c6a80185fbe86e438d02f1ccea1601cf4;p=lhc%2Fweb%2Fwiklou.git

diff --git a/includes/JobQueue.php b/includes/JobQueue.php
index 3eddd50e7f..afa757d752 100644
--- a/includes/JobQueue.php
+++ b/includes/JobQueue.php
@@ -1,109 +1,248 @@
 <?php
+/**
+ * @defgroup JobQueue JobQueue
+ */
 
 if ( !defined( 'MEDIAWIKI' ) ) {
 	die( "This file is part of MediaWiki, it is not a valid entry point\n" );
 }
 
-class Job {
+/**
+ * Class to both describe a background job and handle jobs.
+ *
+ * @ingroup JobQueue
+ */
+abstract class Job {
 	var $command,
 		$title,
-		$params, 
+		$params,
 		$id,
-		$removeDuplicates, 
+		$removeDuplicates,
 		$error;
 
+	/*-------------------------------------------------------------------------
+	 * Abstract functions
+	 *------------------------------------------------------------------------*/
+
+	/**
+	 * Run the job
+	 * @return boolean success
+	 */
+	abstract function run();
+
 	/*-------------------------------------------------------------------------
 	 * Static functions
 	 *------------------------------------------------------------------------*/
+
+	/**
+	 * @deprecated use LinksUpdate::queueRecursiveJobs()
+	 */
+	/**
+	 * static function queueLinksJobs( $titles ) {}
+	 */
+
 	/**
-	 * Add an array of refreshLinks jobs to the queue
-	 * @param array $titles Array of title objects. 
-	 * @static
+	 * Pop a job of a certain type.  This tries less hard than pop() to
+	 * actually find a job; it may be adversely affected by concurrent job
+	 * runners.
 	 */
-	function queueLinksJobs( $titles ) {
-		$fname = 'Job::queueLinksJobs';
-		wfProfileIn( $fname );
-		foreach ( $titles as $title ) {
-			$job = new Job( 'refreshLinks', $title );
-			$job->insert();
+	static function pop_type($type) {
+		wfProfilein( __METHOD__ );
+
+		$dbw = wfGetDB( DB_MASTER );
+
+
+		$row = $dbw->selectRow( 'job', '*', array( 'job_cmd' => $type ), __METHOD__,
+				array( 'LIMIT' => 1 ));
+
+		if ($row === false) {
+			wfProfileOut( __METHOD__ );
+			return false;
+		}
+
+		/* Ensure we "own" this row */
+		$dbw->delete( 'job', array( 'job_id' => $row->job_id ), __METHOD__ );
+		$affected = $dbw->affectedRows();
+
+		if ($affected == 0) {
+			wfProfileOut( __METHOD__ );
+			return false;
 		}
-		wfProfileOut( $fname );
+
+		$namespace = $row->job_namespace;
+		$dbkey = $row->job_title;
+		$title = Title::makeTitleSafe( $namespace, $dbkey );
+		$job = Job::factory( $row->job_cmd, $title, Job::extractBlob( $row->job_params ), $row->job_id );
+
+		$dbw->delete( 'job', $job->insertFields(), __METHOD__ );
+		$dbw->immediateCommit();
+
+		wfProfileOut( __METHOD__ );
+		return $job;
 	}
 
 	/**
 	 * Pop a job off the front of the queue
-	 * @static
+	 *
+	 * @param $offset Number of jobs to skip
 	 * @return Job or false if there's no jobs
 	 */
-	function pop() {
-		$fname = 'Job::pop';
-		wfProfileIn( $fname );
+	static function pop($offset=0) {
+		wfProfileIn( __METHOD__ );
 
-		$dbr =& wfGetDB( DB_SLAVE );
+		$dbr = wfGetDB( DB_SLAVE );
 
-		// Get a job from the slave
-		$row = $dbr->selectRow( 'job', '*', '', $fname, 
-			array( 'ORDER BY' => 'job_id', 'LIMIT' => 1 )
-		);
+		/* Get a job from the slave, start with an offset,
+			scan full set afterwards, avoid hitting purged rows
 
-		if ( $row === false ) {
-			wfProfileOut( $fname );
-			return false;
+			NB: If random fetch previously was used, offset
+				will always be ahead of few entries
+		*/
+
+		$row = $dbr->selectRow( 'job', '*', "job_id >= ${offset}", __METHOD__,
+			array( 'ORDER BY' => 'job_id', 'LIMIT' => 1 ));
+
+		// Refetching without offset is needed as some of job IDs could have had delayed commits
+		// and have lower IDs than jobs already executed, blame concurrency :)
+		//
+		if ( $row === false) {
+			if ($offset!=0)
+				$row = $dbr->selectRow( 'job', '*', '', __METHOD__,
+					array( 'ORDER BY' => 'job_id', 'LIMIT' => 1 ));
+
+			if ($row === false ) {
+				wfProfileOut( __METHOD__ );
+				return false;
+			}
 		}
+		$offset = $row->job_id;
 
 		// Try to delete it from the master
-		$dbw =& wfGetDB( DB_MASTER );
-		$dbw->delete( 'job', array( 'job_id' => $row->job_id ), $fname );
+		$dbw = wfGetDB( DB_MASTER );
+		$dbw->delete( 'job', array( 'job_id' => $row->job_id ), __METHOD__ );
 		$affected = $dbw->affectedRows();
 		$dbw->immediateCommit();
 
 		if ( !$affected ) {
 			// Failed, someone else beat us to it
 			// Try getting a random row
-			$row = $dbw->selectRow( 'job', array( 'MIN(job_id) as minjob', 
-				'MAX(job_id) as maxjob' ), '', $fname );
+			$row = $dbw->selectRow( 'job', array( 'MIN(job_id) as minjob',
+				'MAX(job_id) as maxjob' ), '1=1', __METHOD__ );
 			if ( $row === false || is_null( $row->minjob ) || is_null( $row->maxjob ) ) {
 				// No jobs to get
-				wfProfileOut( $fname );
+				wfProfileOut( __METHOD__ );
 				return false;
 			}
 			// Get the random row
-			$row = $dbw->selectRow( 'job', '*', 
-				array( 'job_id' => mt_rand( $row->minjob, $row->maxjob ) ),	$fname );
+			$row = $dbw->selectRow( 'job', '*',
+				'job_id >= ' . mt_rand( $row->minjob, $row->maxjob ),	__METHOD__ );
 			if ( $row === false ) {
 				// Random job gone before we got the chance to select it
 				// Give up
-				wfProfileOut( $fname );
+				wfProfileOut( __METHOD__ );
 				return false;
 			}
 			// Delete the random row
-			$dbw->delete( 'job', array( 'job_id' => $row->job_id ), $fname );
+			$dbw->delete( 'job', array( 'job_id' => $row->job_id ), __METHOD__ );
 			$affected = $dbw->affectedRows();
 			$dbw->immediateCommit();
-			
+
 			if ( !$affected ) {
 				// Random job gone before we exclusively deleted it
 				// Give up
-				wfProfileOut( $fname );
+				wfProfileOut( __METHOD__ );
 				return false;
-			}				
+			}
 		}
-		
+
 		// If execution got to here, there's a row in $row that has been deleted from the database
 		// by this thread. Hence the concurrent pop was successful.
 		$namespace = $row->job_namespace;
 		$dbkey = $row->job_title;
 		$title = Title::makeTitleSafe( $namespace, $dbkey );
-		$job = new Job( $row->job_cmd, $title, $row->job_params, $row->job_id );
-		wfProfileOut( $fname );
+		$job = Job::factory( $row->job_cmd, $title, Job::extractBlob( $row->job_params ), $row->job_id );
+
+		// Remove any duplicates it may have later in the queue
+		// Deadlock prone section
+		$dbw->begin();
+		$dbw->delete( 'job', $job->insertFields(), __METHOD__ );
+		$dbw->commit();
+
+		wfProfileOut( __METHOD__ );
 		return $job;
 	}
 
+	/**
+	 * Create the appropriate object to handle a specific job
+	 *
+	 * @param $command String: Job command
+	 * @param $title Title: Associated title
+	 * @param $params Array: Job parameters
+	 * @param $id Int: Job identifier
+	 * @return Job
+	 */
+	static function factory( $command, $title, $params = false, $id = 0 ) {
+		global $wgJobClasses;
+		if( isset( $wgJobClasses[$command] ) ) {
+			$class = $wgJobClasses[$command];
+			return new $class( $title, $params, $id );
+		}
+		throw new MWException( "Invalid job command `{$command}`" );
+	}
+
+	static function makeBlob( $params ) {
+		if ( $params !== false ) {
+			return serialize( $params );
+		} else {
+			return '';
+		}
+	}
+
+	static function extractBlob( $blob ) {
+		if ( (string)$blob !== '' ) {
+			return unserialize( $blob );
+		} else {
+			return false;
+		}
+	}
+
+	/**
+	 * Batch-insert a group of jobs into the queue.
+	 * This will be wrapped in a transaction with a forced commit.
+	 *
+	 * This may add duplicate at insert time, but they will be
+	 * removed later on, when the first one is popped.
+	 *
+	 * @param $jobs array of Job objects
+	 */
+	static function batchInsert( $jobs ) {
+		if( !count( $jobs ) ) {
+			return;
+		}
+		$dbw = wfGetDB( DB_MASTER );
+		$rows = array();
+		foreach( $jobs as $job ) {
+			$rows[] = $job->insertFields();
+			if ( count( $rows ) >= 50 ) {
+				# Do a small transaction to avoid slave lag
+				$dbw->begin();
+				$dbw->insert( 'job', $rows, __METHOD__, 'IGNORE' );
+				$dbw->commit();
+				$rows = array();
+			}
+		}
+		if ( $rows ) {
+			$dbw->begin();
+			$dbw->insert( 'job', $rows, __METHOD__, 'IGNORE' );
+			$dbw->commit();
+		}
+	}
+
 	/*-------------------------------------------------------------------------
 	 * Non-static functions
 	 *------------------------------------------------------------------------*/
 
-	function Job( $command, $title, $params = '', $id = 0 ) {
+	function __construct( $command, $title, $params = false, $id = 0 ) {
 		$this->command = $command;
 		$this->title = $title;
 		$this->params = $params;
@@ -114,101 +253,60 @@ class Job {
 		$this->removeDuplicates = true;
 	}
 
+	/**
+	 * Insert a single job into the queue.
+	 */
 	function insert() {
-		$fname = 'Job::insert';
+		$fields = $this->insertFields();
 
-		$fields = array(
-			'job_cmd' => $this->command,
-			'job_namespace' => $this->title->getNamespace(),
-			'job_title' => $this->title->getDBkey(),
-			'job_params' => $this->params
-		);
+		$dbw = wfGetDB( DB_MASTER );
 
-		$dbw =& wfGetDB( DB_MASTER );
-		
 		if ( $this->removeDuplicates ) {
-			$res = $dbw->select( 'job', array( '1' ), $fields, $fname );
+			$res = $dbw->select( 'job', array( '1' ), $fields, __METHOD__ );
 			if ( $dbw->numRows( $res ) ) {
 				return;
 			}
 		}
 		$fields['job_id'] = $dbw->nextSequenceValue( 'job_job_id_seq' );
-		$dbw->insert( 'job', $fields, $fname );
+		$dbw->insert( 'job', $fields, __METHOD__ );
 	}
 
-	/**
-	 * Run the job
-	 * @return boolean success
-	 */
-	function run() {
-		$fname = 'Job::run';
-		wfProfileIn( $fname );
-		switch ( $this->command ) {
-			case 'refreshLinks':
-				$retval = $this->refreshLinks();
-				break;
-			default:
-				$this->error = "Invalid job type {$this->command}, ignoring";
-				wfDebug( $this->error . "\n" );
-				$retval = false;
-		}
-		wfProfileOut( $fname );
-		return $retval;
+	protected function insertFields() {
+		return array(
+			'job_cmd' => $this->command,
+			'job_namespace' => $this->title->getNamespace(),
+			'job_title' => $this->title->getDBkey(),
+			'job_params' => Job::makeBlob( $this->params )
+		);
 	}
 
-	/**
-	 * Run a refreshLinks job
-	 * @return boolean success
-	 */
-	function refreshLinks() {
-		global $wgParser;
-		$fname = 'Job::refreshLinks';
-		wfProfileIn( $fname );
-		
-		$dbw =& wfGetDB( DB_MASTER );
-
-		$linkCache =& LinkCache::singleton();
-		$linkCache->clear();
-		
-		if ( is_null( $this->title ) ) {
-			$this->error = "refreshLinks: Invalid title";
-			wfProfileOut( $fname );
-			return false;
-		}
-
-		$revision = Revision::newFromTitle( $this->title );
-		if ( !$revision ) {
-			$this->error = 'refreshLinks: Article not found "' . $this->title->getPrefixedDBkey() . '"';
-			wfProfileOut( $fname );
-			return false;
+	function toString() {
+		$paramString = '';
+		if ( $this->params ) {
+			foreach ( $this->params as $key => $value ) {
+				if ( $paramString != '' ) {
+					$paramString .= ' ';
+				}
+				$paramString .= "$key=$value";
+			}
 		}
 
-		wfProfileIn( "$fname-parse" );
-		$options = new ParserOptions;
-		$parserOutput = $wgParser->parse( $revision->getText(), $this->title, $options, true, true, $revision->getId() );
-		wfProfileOut( "$fname-parse" );
-		wfProfileIn( "$fname-update" );
-		$update = new LinksUpdate( $this->title, $parserOutput, false );
-		$update->doUpdate();
-		wfProfileOut( "$fname-update" );
-		wfProfileOut( $fname );
-		return true;
-	}
-
-	function toString() {
 		if ( is_object( $this->title ) ) {
 			$s = "{$this->command} " . $this->title->getPrefixedDBkey();
-			if ( $this->params !== '' ) {
-				$s .= ', ' . $this->params;
+			if ( $paramString !== '' ) {
+				$s .= ' ' . $paramString;
 			}
 			return $s;
 		} else {
-			return "{$this->command} {$this->params}";
-		}			
+			return "{$this->command} $paramString";
+		}
+	}
+
+	protected function setLastError( $error ) {
+		$this->error = $error;
 	}
 
 	function getLastError() {
 		return $this->error;
 	}
 }
-?>