Update to MediaWiki 1.21.1

1 files changed, 351 insertions, 0 deletions

diff --git a/includes/job/JobQueueGroup.php b/includes/job/JobQueueGroup.php
new file mode 100644
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+++ b/includes/job/JobQueueGroup.php
@@ -0,0 +1,351 @@
+<?php
+/**
+ * Job queue base code.
+ *
+ * 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 Aaron Schulz
+ */
+
+/**
+ * Class to handle enqueueing of background jobs
+ *
+ * @ingroup JobQueue
+ * @since 1.21
+ */
+class JobQueueGroup {
+	/** @var Array */
+	protected static $instances = array();
+
+	/** @var ProcessCacheLRU */
+	protected $cache;
+
+	protected $wiki; // string; wiki ID
+
+	const TYPE_DEFAULT = 1; // integer; jobs popped by default
+	const TYPE_ANY = 2; // integer; any job
+
+	const USE_CACHE = 1; // integer; use process or persistent cache
+
+	const PROC_CACHE_TTL = 15; // integer; seconds
+
+	const CACHE_VERSION = 1; // integer; cache version
+
+	/**
+	 * @param string $wiki Wiki ID
+	 */
+	protected function __construct( $wiki ) {
+		$this->wiki = $wiki;
+		$this->cache = new ProcessCacheLRU( 10 );
+	}
+
+	/**
+	 * @param string $wiki Wiki ID
+	 * @return JobQueueGroup
+	 */
+	public static function singleton( $wiki = false ) {
+		$wiki = ( $wiki === false ) ? wfWikiID() : $wiki;
+		if ( !isset( self::$instances[$wiki] ) ) {
+			self::$instances[$wiki] = new self( $wiki );
+		}
+		return self::$instances[$wiki];
+	}
+
+	/**
+	 * Destroy the singleton instances
+	 *
+	 * @return void
+	 */
+	public static function destroySingletons() {
+		self::$instances = array();
+	}
+
+	/**
+	 * Get the job queue object for a given queue type
+	 *
+	 * @param $type string
+	 * @return JobQueue
+	 */
+	public function get( $type ) {
+		global $wgJobTypeConf;
+
+		$conf = array( 'wiki' => $this->wiki, 'type' => $type );
+		if ( isset( $wgJobTypeConf[$type] ) ) {
+			$conf = $conf + $wgJobTypeConf[$type];
+		} else {
+			$conf = $conf + $wgJobTypeConf['default'];
+		}
+
+		return JobQueue::factory( $conf );
+	}
+
+	/**
+	 * Insert jobs into the respective queues of with the belong.
+	 *
+	 * This inserts the jobs into the queue specified by $wgJobTypeConf
+	 * and updates the aggregate job queue information cache as needed.
+	 *
+	 * @param $jobs Job|array A single Job or a list of Jobs
+	 * @throws MWException
+	 * @return bool
+	 */
+	public function push( $jobs ) {
+		$jobs = is_array( $jobs ) ? $jobs : array( $jobs );
+
+		$jobsByType = array(); // (job type => list of jobs)
+		foreach ( $jobs as $job ) {
+			if ( $job instanceof Job ) {
+				$jobsByType[$job->getType()][] = $job;
+			} else {
+				throw new MWException( "Attempted to push a non-Job object into a queue." );
+			}
+		}
+
+		$ok = true;
+		foreach ( $jobsByType as $type => $jobs ) {
+			if ( $this->get( $type )->push( $jobs ) ) {
+				JobQueueAggregator::singleton()->notifyQueueNonEmpty( $this->wiki, $type );
+			} else {
+				$ok = false;
+			}
+		}
+
+		if ( $this->cache->has( 'queues-ready', 'list' ) ) {
+			$list = $this->cache->get( 'queues-ready', 'list' );
+			if ( count( array_diff( array_keys( $jobsByType ), $list ) ) ) {
+				$this->cache->clear( 'queues-ready' );
+			}
+		}
+
+		return $ok;
+	}
+
+	/**
+	 * Pop a job off one of the job queues
+	 *
+	 * This pops a job off a queue as specified by $wgJobTypeConf and
+	 * updates the aggregate job queue information cache as needed.
+	 *
+	 * @param $qtype integer|string JobQueueGroup::TYPE_DEFAULT or type string
+	 * @param $flags integer Bitfield of JobQueueGroup::USE_* constants
+	 * @return Job|bool Returns false on failure
+	 */
+	public function pop( $qtype = self::TYPE_DEFAULT, $flags = 0 ) {
+		if ( is_string( $qtype ) ) { // specific job type
+			$job = $this->get( $qtype )->pop();
+			if ( !$job ) {
+				JobQueueAggregator::singleton()->notifyQueueEmpty( $this->wiki, $qtype );
+			}
+			return $job;
+		} else { // any job in the "default" jobs types
+			if ( $flags & self::USE_CACHE ) {
+				if ( !$this->cache->has( 'queues-ready', 'list', self::PROC_CACHE_TTL ) ) {
+					$this->cache->set( 'queues-ready', 'list', $this->getQueuesWithJobs() );
+				}
+				$types = $this->cache->get( 'queues-ready', 'list' );
+			} else {
+				$types = $this->getQueuesWithJobs();
+			}
+
+			if ( $qtype == self::TYPE_DEFAULT ) {
+				$types = array_intersect( $types, $this->getDefaultQueueTypes() );
+			}
+			shuffle( $types ); // avoid starvation
+
+			foreach ( $types as $type ) { // for each queue...
+				$job = $this->get( $type )->pop();
+				if ( $job ) { // found
+					return $job;
+				} else { // not found
+					JobQueueAggregator::singleton()->notifyQueueEmpty( $this->wiki, $type );
+					$this->cache->clear( 'queues-ready' );
+				}
+			}
+
+			return false; // no jobs found
+		}
+	}
+
+	/**
+	 * Acknowledge that a job was completed
+	 *
+	 * @param $job Job
+	 * @return bool
+	 */
+	public function ack( Job $job ) {
+		return $this->get( $job->getType() )->ack( $job );
+	}
+
+	/**
+	 * Register the "root job" of a given job into the queue for de-duplication.
+	 * This should only be called right *after* all the new jobs have been inserted.
+	 *
+	 * @param $job Job
+	 * @return bool
+	 */
+	public function deduplicateRootJob( Job $job ) {
+		return $this->get( $job->getType() )->deduplicateRootJob( $job );
+	}
+
+	/**
+	 * Wait for any slaves or backup queue servers to catch up.
+	 *
+	 * This does nothing for certain queue classes.
+	 *
+	 * @return void
+	 * @throws MWException
+	 */
+	public function waitForBackups() {
+		global $wgJobTypeConf;
+
+		wfProfileIn( __METHOD__ );
+		// Try to avoid doing this more than once per queue storage medium
+		foreach ( $wgJobTypeConf as $type => $conf ) {
+			$this->get( $type )->waitForBackups();
+		}
+		wfProfileOut( __METHOD__ );
+	}
+
+	/**
+	 * Get the list of queue types
+	 *
+	 * @return array List of strings
+	 */
+	public function getQueueTypes() {
+		return array_keys( $this->getCachedConfigVar( 'wgJobClasses' ) );
+	}
+
+	/**
+	 * Get the list of default queue types
+	 *
+	 * @return array List of strings
+	 */
+	public function getDefaultQueueTypes() {
+		global $wgJobTypesExcludedFromDefaultQueue;
+
+		return array_diff( $this->getQueueTypes(), $wgJobTypesExcludedFromDefaultQueue );
+	}
+
+	/**
+	 * Get the list of job types that have non-empty queues
+	 *
+	 * @return Array List of job types that have non-empty queues
+	 */
+	public function getQueuesWithJobs() {
+		$types = array();
+		foreach ( $this->getQueueTypes() as $type ) {
+			if ( !$this->get( $type )->isEmpty() ) {
+				$types[] = $type;
+			}
+		}
+		return $types;
+	}
+
+	/**
+	 * Check if jobs should not be popped of a queue right now.
+	 * This is only used for performance, such as to avoid spamming
+	 * the queue with many sub-jobs before they actually get run.
+	 *
+	 * @param $type string
+	 * @return bool
+	 */
+	public function isQueueDeprioritized( $type ) {
+		if ( $type === 'refreshLinks2' ) {
+			// Don't keep converting refreshLinks2 => refreshLinks jobs if the
+			// later jobs have not been done yet. This helps throttle queue spam.
+			return !$this->get( 'refreshLinks' )->isEmpty();
+		}
+		return false;
+	}
+
+	/**
+	 * Execute any due periodic queue maintenance tasks for all queues.
+	 *
+	 * A task is "due" if the time ellapsed since the last run is greater than
+	 * the defined run period. Concurrent calls to this function will cause tasks
+	 * to be attempted twice, so they may need their own methods of mutual exclusion.
+	 *
+	 * @return integer Number of tasks run
+	 */
+	public function executeReadyPeriodicTasks() {
+		global $wgMemc;
+
+		list( $db, $prefix ) = wfSplitWikiID( $this->wiki );
+		$key = wfForeignMemcKey( $db, $prefix, 'jobqueuegroup', 'taskruns', 'v1' );
+		$lastRuns = $wgMemc->get( $key ); // (queue => task => UNIX timestamp)
+
+		$count = 0;
+		$tasksRun = array(); // (queue => task => UNIX timestamp)
+		foreach ( $this->getQueueTypes() as $type ) {
+			$queue = $this->get( $type );
+			foreach ( $queue->getPeriodicTasks() as $task => $definition ) {
+				if ( $definition['period'] <= 0 ) {
+					continue; // disabled
+				} elseif ( !isset( $lastRuns[$type][$task] )
+					|| $lastRuns[$type][$task] < ( time() - $definition['period'] ) )
+				{
+					if ( call_user_func( $definition['callback'] ) !== null ) {
+						$tasksRun[$type][$task] = time();
+						++$count;
+					}
+				}
+			}
+		}
+
+		$wgMemc->merge( $key, function( $cache, $key, $lastRuns ) use ( $tasksRun ) {
+			if ( is_array( $lastRuns ) ) {
+				foreach ( $tasksRun as $type => $tasks ) {
+					foreach ( $tasks as $task => $timestamp ) {
+						if ( !isset( $lastRuns[$type][$task] )
+							|| $timestamp > $lastRuns[$type][$task] )
+						{
+							$lastRuns[$type][$task] = $timestamp;
+						}
+					}
+				}
+			} else {
+				$lastRuns = $tasksRun;
+			}
+			return $lastRuns;
+		} );
+
+		return $count;
+	}
+
+	/**
+	 * @param $name string
+	 * @return mixed
+	 */
+	private function getCachedConfigVar( $name ) {
+		global $wgConf, $wgMemc;
+
+		if ( $this->wiki === wfWikiID() ) {
+			return $GLOBALS[$name]; // common case
+		} else {
+			list( $db, $prefix ) = wfSplitWikiID( $this->wiki );
+			$key = wfForeignMemcKey( $db, $prefix, 'configvalue', $name );
+			$value = $wgMemc->get( $key ); // ('v' => ...) or false
+			if ( is_array( $value ) ) {
+				return $value['v'];
+			} else {
+				$value = $wgConf->getConfig( $this->wiki, $name );
+				$wgMemc->set( $key, array( 'v' => $value ), 86400 + mt_rand( 0, 86400 ) );
+				return $value;
+			}
+		}
+	}
+}