includes/job/Job.php

   1 <?php
   2 /**
   3  * Job queue base code.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @defgroup JobQueue JobQueue
  22  */
  23
  24 /**
  25  * Class to both describe a background job and handle jobs.
  26  * This queue aspects of this class are now deprecated.
  27  *
  28  * @ingroup JobQueue
  29  */
  30 abstract class Job {
  31         /**
  32          * @var Title
  33          */
  34         var $title;
  35
  36         var $command,
  37                 $params,
  38                 $id,
  39                 $removeDuplicates,
  40                 $error;
  41
  42         /*-------------------------------------------------------------------------
  43          * Abstract functions
  44          *------------------------------------------------------------------------*/
  45
  46         /**
  47          * Run the job
  48          * @return boolean success
  49          */
  50         abstract public function run();
  51
  52         /*-------------------------------------------------------------------------
  53          * Static functions
  54          *------------------------------------------------------------------------*/
  55
  56         /**
  57          * Create the appropriate object to handle a specific job
  58          *
  59          * @param $command String: Job command
  60          * @param $title Title: Associated title
  61          * @param $params Array|bool: Job parameters
  62          * @param $id Int: Job identifier
  63          * @throws MWException
  64          * @return Job
  65          */
  66         public static function factory( $command, Title $title, $params = false, $id = 0 ) {
  67                 global $wgJobClasses;
  68                 if( isset( $wgJobClasses[$command] ) ) {
  69                         $class = $wgJobClasses[$command];
  70                         return new $class( $title, $params, $id );
  71                 }
  72                 throw new MWException( "Invalid job command `{$command}`" );
  73         }
  74
  75         /**
  76          * Batch-insert a group of jobs into the queue.
  77          * This will be wrapped in a transaction with a forced commit.
  78          *
  79          * This may add duplicate at insert time, but they will be
  80          * removed later on, when the first one is popped.
  81          *
  82          * @param $jobs array of Job objects
  83          * @deprecated 1.20
  84          */
  85         public static function batchInsert( $jobs ) {
  86                 return JobQueueGroup::singleton()->push( $jobs );
  87         }
  88
  89         /**
  90          * Insert a group of jobs into the queue.
  91          *
  92          * Same as batchInsert() but does not commit and can thus
  93          * be rolled-back as part of a larger transaction. However,
  94          * large batches of jobs can cause slave lag.
  95          *
  96          * @param $jobs array of Job objects
  97          * @deprecated 1.20
  98          */
  99         public static function safeBatchInsert( $jobs ) {
 100                 return JobQueueGroup::singleton()->push( $jobs, JobQueue::QoS_Atomic );
 101         }
 102
 103         /*-------------------------------------------------------------------------
 104          * Non-static functions
 105          *------------------------------------------------------------------------*/
 106
 107         /**
 108          * @param $command
 109          * @param $title
 110          * @param $params array|bool
 111          * @param $id int
 112          */
 113         public function __construct( $command, $title, $params = false, $id = 0 ) {
 114                 $this->command = $command;
 115                 $this->title = $title;
 116                 $this->params = $params;
 117                 $this->id = $id;
 118
 119                 $this->removeDuplicates = false; // expensive jobs may set this to true
 120         }
 121
 122         /**
 123          * @return integer May be 0 for jobs stored outside the DB
 124          */
 125         public function getId() {
 126                 return $this->id;
 127         }
 128
 129         /**
 130          * @return string
 131          */
 132         public function getType() {
 133                 return $this->command;
 134         }
 135
 136         /**
 137          * @return Title
 138          */
 139         public function getTitle() {
 140                 return $this->title;
 141         }
 142
 143         /**
 144          * @return array
 145          */
 146         public function getParams() {
 147                 return $this->params;
 148         }
 149
 150         /**
 151          * @return bool
 152          */
 153         public function ignoreDuplicates() {
 154                 return $this->removeDuplicates;
 155         }
 156
 157         /**
 158          * Insert a single job into the queue.
 159          * @return bool true on success
 160          * @deprecated 1.20
 161          */
 162         public function insert() {
 163                 return JobQueueGroup::singleton()->push( $this );
 164         }
 165
 166         /**
 167          * @return string
 168          */
 169         public function toString() {
 170                 $paramString = '';
 171                 if ( $this->params ) {
 172                         foreach ( $this->params as $key => $value ) {
 173                                 if ( $paramString != '' ) {
 174                                         $paramString .= ' ';
 175                                 }
 176                                 $paramString .= "$key=$value";
 177                         }
 178                 }
 179
 180                 if ( is_object( $this->title ) ) {
 181                         $s = "{$this->command} " . $this->title->getPrefixedDBkey();
 182                         if ( $paramString !== '' ) {
 183                                 $s .= ' ' . $paramString;
 184                         }
 185                         return $s;
 186                 } else {
 187                         return "{$this->command} $paramString";
 188                 }
 189         }
 190
 191         protected function setLastError( $error ) {
 192                 $this->error = $error;
 193         }
 194
 195         public function getLastError() {
 196                 return $this->error;
 197         }
 198 }