includes/SecondaryDBDataUpdate.php

   1 <?php
   2 /**
   3  * See docs/deferred.txt
   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  * Abstract base class for update jobs that put some secondary data extracted
  21  * from article content into the database.
  22  */
  23 abstract class SecondaryDBDataUpdate extends SecondaryDataUpdate {
  24
  25         /**@{{
  26          * @private
  27          */
  28         var $mDb,            //!< Database connection reference
  29                 $mOptions;       //!< SELECT options to be used (array)
  30         /**@}}*/
  31
  32         /**
  33          * Constructor
  34          *
  35          * @param $title Title of the page we're updating
  36          * @param $parserOutput ParserOutput: output from a full parse of this page
  37          * @param $recursive Boolean: queue jobs for recursive updates?
  38          */
  39     public function __construct( Title $title, ParserOutput $parserOutput ) {
  40                 global $wgAntiLockFlags;
  41
  42         parent::__construct( $title, $parserOutput );
  43
  44                 if ( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) {
  45                         $this->mOptions = array();
  46                 } else {
  47                         $this->mOptions = array( 'FOR UPDATE' );
  48                 }
  49                 $this->mDb = wfGetDB( DB_MASTER );
  50         }
  51
  52         /**
  53          * Invalidate the cache of a list of pages from a single namespace
  54          *
  55          * @param $namespace Integer
  56          * @param $dbkeys Array
  57          */
  58         public function invalidatePages( $namespace, $dbkeys ) {
  59                 if ( !count( $dbkeys ) ) {
  60                         return;
  61                 }
  62
  63                 /**
  64                  * Determine which pages need to be updated
  65                  * This is necessary to prevent the job queue from smashing the DB with
  66                  * large numbers of concurrent invalidations of the same page
  67                  */
  68                 $now = $this->mDb->timestamp();
  69                 $ids = array();
  70                 $res = $this->mDb->select( 'page', array( 'page_id' ),
  71                         array(
  72                                 'page_namespace' => $namespace,
  73                                 'page_title IN (' . $this->mDb->makeList( $dbkeys ) . ')',
  74                                 'page_touched < ' . $this->mDb->addQuotes( $now )
  75                         ), __METHOD__
  76                 );
  77                 foreach ( $res as $row ) {
  78                         $ids[] = $row->page_id;
  79                 }
  80                 if ( !count( $ids ) ) {
  81                         return;
  82                 }
  83
  84                 /**
  85                  * Do the update
  86                  * We still need the page_touched condition, in case the row has changed since
  87                  * the non-locking select above.
  88                  */
  89                 $this->mDb->update( 'page', array( 'page_touched' => $now ),
  90                         array(
  91                                 'page_id IN (' . $this->mDb->makeList( $ids ) . ')',
  92                                 'page_touched < ' . $this->mDb->addQuotes( $now )
  93                         ), __METHOD__
  94                 );
  95         }
  96
  97 }