X-Git-Url: https://scripts.mit.edu/gitweb/autoinstallsdev/mediawiki.git/blobdiff_plain/19e297c21b10b1b8a3acad5e73fc71dcb35db44a..6932310fd58ebef145fa01eb76edf7150284d8ea:/includes/jobqueue/Job.php

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+<?php
+/**
+ * Job queue task 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
+ * @defgroup JobQueue JobQueue
+ */
+
+/**
+ * Class to both describe a background job and handle jobs.
+ * The queue aspects of this class are now deprecated.
+ * Using the class to push jobs onto queues is deprecated (use JobSpecification).
+ *
+ * @ingroup JobQueue
+ */
+abstract class Job implements IJobSpecification {
+	/** @var string */
+	public $command;
+
+	/** @var array Array of job parameters */
+	public $params;
+
+	/** @var array Additional queue metadata */
+	public $metadata = [];
+
+	/** @var Title */
+	protected $title;
+
+	/** @var bool Expensive jobs may set this to true */
+	protected $removeDuplicates;
+
+	/** @var string Text for error that occurred last */
+	protected $error;
+
+	/** @var callable[] */
+	protected $teardownCallbacks = [];
+
+	/**
+	 * Run the job
+	 * @return bool Success
+	 */
+	abstract public function run();
+
+	/**
+	 * Create the appropriate object to handle a specific job
+	 *
+	 * @param string $command Job command
+	 * @param Title $title Associated title
+	 * @param array $params Job parameters
+	 * @throws MWException
+	 * @return Job
+	 */
+	public static function factory( $command, Title $title, $params = [] ) {
+		global $wgJobClasses;
+
+		if ( isset( $wgJobClasses[$command] ) ) {
+			$handler = $wgJobClasses[$command];
+
+			if ( is_callable( $handler ) ) {
+				$job = call_user_func( $handler, $title, $params );
+			} elseif ( class_exists( $handler ) ) {
+				$job = new $handler( $title, $params );
+			} else {
+				$job = null;
+			}
+
+			if ( $job instanceof Job ) {
+				$job->command = $command;
+				return $job;
+			} else {
+				throw new InvalidArgumentException( "Cannot instantiate job '$command': bad spec!" );
+			}
+		}
+
+		throw new InvalidArgumentException( "Invalid job command '{$command}'" );
+	}
+
+	/**
+	 * @param string $command
+	 * @param Title $title
+	 * @param array|bool $params Can not be === true
+	 */
+	public function __construct( $command, $title, $params = false ) {
+		$this->command = $command;
+		$this->title = $title;
+		$this->params = is_array( $params ) ? $params : []; // sanity
+
+		// expensive jobs may set this to true
+		$this->removeDuplicates = false;
+
+		if ( !isset( $this->params['requestId'] ) ) {
+			$this->params['requestId'] = WebRequest::getRequestId();
+		}
+	}
+
+	/**
+	 * 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 Job[] $jobs Array of Job objects
+	 * @return bool
+	 * @deprecated since 1.21
+	 */
+	public static function batchInsert( $jobs ) {
+		wfDeprecated( __METHOD__, '1.21' );
+		JobQueueGroup::singleton()->push( $jobs );
+		return true;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function getType() {
+		return $this->command;
+	}
+
+	/**
+	 * @return Title
+	 */
+	public function getTitle() {
+		return $this->title;
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getParams() {
+		return $this->params;
+	}
+
+	/**
+	 * @return int|null UNIX timestamp to delay running this job until, otherwise null
+	 * @since 1.22
+	 */
+	public function getReleaseTimestamp() {
+		return isset( $this->params['jobReleaseTimestamp'] )
+			? wfTimestampOrNull( TS_UNIX, $this->params['jobReleaseTimestamp'] )
+			: null;
+	}
+
+	/**
+	 * @return int|null UNIX timestamp of when the job was queued, or null
+	 * @since 1.26
+	 */
+	public function getQueuedTimestamp() {
+		return isset( $this->metadata['timestamp'] )
+			? wfTimestampOrNull( TS_UNIX, $this->metadata['timestamp'] )
+			: null;
+	}
+
+	/**
+	 * @return string|null Id of the request that created this job. Follows
+	 *  jobs recursively, allowing to track the id of the request that started a
+	 *  job when jobs insert jobs which insert other jobs.
+	 * @since 1.27
+	 */
+	public function getRequestId() {
+		return isset( $this->params['requestId'] )
+			? $this->params['requestId']
+			: null;
+	}
+
+	/**
+	 * @return int|null UNIX timestamp of when the job was runnable, or null
+	 * @since 1.26
+	 */
+	public function getReadyTimestamp() {
+		return $this->getReleaseTimestamp() ?: $this->getQueuedTimestamp();
+	}
+
+	/**
+	 * Whether the queue should reject insertion of this job if a duplicate exists
+	 *
+	 * This can be used to avoid duplicated effort or combined with delayed jobs to
+	 * coalesce updates into larger batches. Claimed jobs are never treated as
+	 * duplicates of new jobs, and some queues may allow a few duplicates due to
+	 * network partitions and fail-over. Thus, additional locking is needed to
+	 * enforce mutual exclusion if this is really needed.
+	 *
+	 * @return bool
+	 */
+	public function ignoreDuplicates() {
+		return $this->removeDuplicates;
+	}
+
+	/**
+	 * @return bool Whether this job can be retried on failure by job runners
+	 * @since 1.21
+	 */
+	public function allowRetries() {
+		return true;
+	}
+
+	/**
+	 * @return int Number of actually "work items" handled in this job
+	 * @see $wgJobBackoffThrottling
+	 * @since 1.23
+	 */
+	public function workItemCount() {
+		return 1;
+	}
+
+	/**
+	 * Subclasses may need to override this to make duplication detection work.
+	 * The resulting map conveys everything that makes the job unique. This is
+	 * only checked if ignoreDuplicates() returns true, meaning that duplicate
+	 * jobs are supposed to be ignored.
+	 *
+	 * @return array Map of key/values
+	 * @since 1.21
+	 */
+	public function getDeduplicationInfo() {
+		$info = [
+			'type' => $this->getType(),
+			'namespace' => $this->getTitle()->getNamespace(),
+			'title' => $this->getTitle()->getDBkey(),
+			'params' => $this->getParams()
+		];
+		if ( is_array( $info['params'] ) ) {
+			// Identical jobs with different "root" jobs should count as duplicates
+			unset( $info['params']['rootJobSignature'] );
+			unset( $info['params']['rootJobTimestamp'] );
+			// Likewise for jobs with different delay times
+			unset( $info['params']['jobReleaseTimestamp'] );
+			// Identical jobs from different requests should count as duplicates
+			unset( $info['params']['requestId'] );
+			// Queues pack and hash this array, so normalize the order
+			ksort( $info['params'] );
+		}
+
+		return $info;
+	}
+
+	/**
+	 * Get "root job" parameters for a task
+	 *
+	 * This is used to no-op redundant jobs, including child jobs of jobs,
+	 * as long as the children inherit the root job parameters. When a job
+	 * with root job parameters and "rootJobIsSelf" set is pushed, the
+	 * deduplicateRootJob() method is automatically called on it. If the
+	 * root job is only virtual and not actually pushed (e.g. the sub-jobs
+	 * are inserted directly), then call deduplicateRootJob() directly.
+	 *
+	 * @see JobQueue::deduplicateRootJob()
+	 *
+	 * @param string $key A key that identifies the task
+	 * @return array Map of:
+	 *   - rootJobIsSelf    : true
+	 *   - rootJobSignature : hash (e.g. SHA1) that identifies the task
+	 *   - rootJobTimestamp : TS_MW timestamp of this instance of the task
+	 * @since 1.21
+	 */
+	public static function newRootJobParams( $key ) {
+		return [
+			'rootJobIsSelf'    => true,
+			'rootJobSignature' => sha1( $key ),
+			'rootJobTimestamp' => wfTimestampNow()
+		];
+	}
+
+	/**
+	 * @see JobQueue::deduplicateRootJob()
+	 * @return array
+	 * @since 1.21
+	 */
+	public function getRootJobParams() {
+		return [
+			'rootJobSignature' => isset( $this->params['rootJobSignature'] )
+				? $this->params['rootJobSignature']
+				: null,
+			'rootJobTimestamp' => isset( $this->params['rootJobTimestamp'] )
+				? $this->params['rootJobTimestamp']
+				: null
+		];
+	}
+
+	/**
+	 * @see JobQueue::deduplicateRootJob()
+	 * @return bool
+	 * @since 1.22
+	 */
+	public function hasRootJobParams() {
+		return isset( $this->params['rootJobSignature'] )
+			&& isset( $this->params['rootJobTimestamp'] );
+	}
+
+	/**
+	 * @see JobQueue::deduplicateRootJob()
+	 * @return bool Whether this is job is a root job
+	 */
+	public function isRootJob() {
+		return $this->hasRootJobParams() && !empty( $this->params['rootJobIsSelf'] );
+	}
+
+	/**
+	 * @param callable $callback A function with one parameter, the success status, which will be
+	 *   false if the job failed or it succeeded but the DB changes could not be committed or
+	 *   any deferred updates threw an exception. (This parameter was added in 1.28.)
+	 * @since 1.27
+	 */
+	protected function addTeardownCallback( $callback ) {
+		$this->teardownCallbacks[] = $callback;
+	}
+
+	/**
+	 * Do any final cleanup after run(), deferred updates, and all DB commits happen
+	 * @param bool $status Whether the job, its deferred updates, and DB commit all succeeded
+	 * @since 1.27
+	 */
+	public function teardown( $status ) {
+		foreach ( $this->teardownCallbacks as $callback ) {
+			call_user_func( $callback, $status );
+		}
+	}
+
+	/**
+	 * Insert a single job into the queue.
+	 * @return bool True on success
+	 * @deprecated since 1.21
+	 */
+	public function insert() {
+		JobQueueGroup::singleton()->push( $this );
+		return true;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function toString() {
+		$paramString = '';
+		if ( $this->params ) {
+			foreach ( $this->params as $key => $value ) {
+				if ( $paramString != '' ) {
+					$paramString .= ' ';
+				}
+				if ( is_array( $value ) ) {
+					$filteredValue = [];
+					foreach ( $value as $k => $v ) {
+						$json = FormatJson::encode( $v );
+						if ( $json === false || mb_strlen( $json ) > 512 ) {
+							$filteredValue[$k] = gettype( $v ) . '(...)';
+						} else {
+							$filteredValue[$k] = $v;
+						}
+					}
+					if ( count( $filteredValue ) <= 10 ) {
+						$value = FormatJson::encode( $filteredValue );
+					} else {
+						$value = "array(" . count( $value ) . ")";
+					}
+				} elseif ( is_object( $value ) && !method_exists( $value, '__toString' ) ) {
+					$value = "object(" . get_class( $value ) . ")";
+				}
+
+				$flatValue = (string)$value;
+				if ( mb_strlen( $value ) > 1024 ) {
+					$flatValue = "string(" . mb_strlen( $value ) . ")";
+				}
+
+				$paramString .= "$key={$flatValue}";
+			}
+		}
+
+		$metaString = '';
+		foreach ( $this->metadata as $key => $value ) {
+			if ( is_scalar( $value ) && mb_strlen( $value ) < 1024 ) {
+				$metaString .= ( $metaString ? ",$key=$value" : "$key=$value" );
+			}
+		}
+
+		$s = $this->command;
+		if ( is_object( $this->title ) ) {
+			$s .= " {$this->title->getPrefixedDBkey()}";
+		}
+		if ( $paramString != '' ) {
+			$s .= " $paramString";
+		}
+		if ( $metaString != '' ) {
+			$s .= " ($metaString)";
+		}
+
+		return $s;
+	}
+
+	protected function setLastError( $error ) {
+		$this->error = $error;
+	}
+
+	public function getLastError() {
+		return $this->error;
+	}
+}