includes/installer/Update.php

   1 <?php
   2 /*
   3  * Class for handling database updates. Roughly based off of updaters.inc, with
   4  * a few improvements :)
   5  */
   6
   7 class Update {
   8
   9         // Array of updates to perform on the database
  10         protected $updates = array();
  11
  12         // Things we'll need
  13         protected $db, $updater;
  14
  15         public function __construct( $db ) {
  16                 $this->db = $db;
  17                 switch( $this->db->getType() ) {
  18                         case 'mysql':
  19                                 $this->updater = new MysqlUpdater();
  20                                 break;
  21                         case 'sqlite':
  22                                 $this->updater = new SqliteUpdater();
  23                                 break;
  24                         case 'oracle':
  25                                 $this->updater = new OracleUpdater();
  26                                 break;
  27                         default:
  28                                 throw new MWException( __METHOD__ . ' called for unsupported $wgDBtype' );
  29                 }
  30         }
  31
  32         public function doUpdates() {
  33                 global $IP;
  34                 require_once( "$IP/maintenance/updaters.inc" );
  35                 $this->loadUpdates();
  36                 foreach ( $this->updates as $version => $updates ) {
  37                         foreach( $updates as $params ) {
  38                                 $func = array_shift( $params );
  39                                 call_user_func_array( $func, $params );
  40                                 flush();
  41                         }
  42                         $this->setAppliedUpdates( $version, $updates );
  43                 }
  44         }
  45
  46         protected function loadUpdates() {
  47                 // If the updatelog table hasn't been upgraded, we can't use the new
  48                 // style of recording our steps. Run all to be safe
  49                 if( !$this->canUseNewUpdatelog() ) {
  50                         $this->updates = $this->updater->getUpdates();
  51                         return;
  52                 }
  53                 foreach( $this->updater->getUpdates() as $version => $updates ) {
  54                         $appliedUpdates = $this->getAppliedUpdates( $version );
  55                         if( !$appliedUpdates || $appliedUpdates != $updates ) {
  56                                 $this->updates[ $version ] = $updates;
  57                         }
  58                 }
  59         }
  60
  61         protected function getAppliedUpdates( $version ) {
  62                 $key = "updatelist-$version";
  63                 $val = $this->db->selectField( 'updatelog', 'ul_value',
  64                         array( 'ul_key' => $key ), __METHOD__ );
  65                 if( !$val ) {
  66                         return null;
  67                 } else {
  68                         return unserialize( $val );
  69                 }
  70         }
  71
  72         private function setAppliedUpdates( $version, $updates = array() ) {
  73                 if( !$this->canUseNewUpdatelog() ) {
  74                         return;
  75                 }
  76                 $key = "updatelist-$version";
  77                 $this->db->delete( 'updatelog', array( 'ul_key' => $key ), __METHOD__ );
  78                 $this->db->insert( 'updatelog',
  79                         array( 'ul_key' => $key, 'ul_value' => serialize( $updates ) ),
  80                          __METHOD__ );
  81         }
  82
  83         /**
  84          * Updatelog was changed in 1.17 to have a ul_value column so we can record
  85          * more information about what kind of updates we've done (that's what this
  86          * class does). Pre-1.17 wikis won't have this column, and really old wikis
  87          * might not even have updatelog at all
  88          *
  89          * @return boolean
  90          */
  91         protected function canUseNewUpdatelog() {
  92                 return $this->db->tableExists( 'updatelog' ) &&
  93                         $this->db->fieldExists( 'updatelog', 'ul_value' );
  94         }
  95 }