includes/deferred/AutoCommitUpdate.php

   1 <?php
   2
   3 namespace MediaWiki\Deferred;
   4
   5 use Wikimedia\Rdbms\IDatabase;
   6
   7 /**
   8  * Deferrable Update for closure/callback updates that should use auto-commit mode
   9  * @since 1.28
  10  */
  11 class AutoCommitUpdate implements DeferrableUpdate, DeferrableCallback {
  12         /** @var IDatabase */
  13         private $dbw;
  14         /** @var string */
  15         private $fname;
  16         /** @var callable|null */
  17         private $callback;
  18
  19         /**
  20          * @param IDatabase $dbw DB handle; update aborts if a transaction now this rolls back
  21          * @param string $fname Caller name (usually __METHOD__)
  22          * @param callable $callback Callback that takes (IDatabase, method name string)
  23          * @param IDatabase[] $conns Cancel the update if a transaction on these
  24          * connections is rolled back [optional]
  25          */
  26         public function __construct( IDatabase $dbw, $fname, callable $callback, array $conns = [] ) {
  27                 $this->dbw = $dbw;
  28                 $this->fname = $fname;
  29                 $this->callback = $callback;
  30                 // Register DB connections for which uncommitted changes are related to this update
  31                 $conns[] = $dbw;
  32                 foreach ( $conns as $conn ) {
  33                         if ( $conn->trxLevel() ) {
  34                                 $conn->onTransactionResolution( [ $this, 'cancelOnRollback' ], $fname );
  35                         }
  36                 }
  37         }
  38
  39         public function doUpdate() {
  40                 if ( !$this->callback ) {
  41                         return;
  42                 }
  43
  44                 $autoTrx = $this->dbw->getFlag( DBO_TRX );
  45                 $this->dbw->clearFlag( DBO_TRX );
  46                 try {
  47                         ( $this->callback )( $this->dbw, $this->fname );
  48                 } finally {
  49                         if ( $autoTrx ) {
  50                                 $this->dbw->setFlag( DBO_TRX );
  51                         }
  52                 }
  53         }
  54
  55         /**
  56          * @internal This method is public so that it works with onTransactionResolution()
  57          * @param int $trigger
  58          */
  59         public function cancelOnRollback( $trigger ) {
  60                 if ( $trigger === IDatabase::TRIGGER_ROLLBACK ) {
  61                         $this->callback = null;
  62                 }
  63         }
  64
  65         public function getOrigin() {
  66                 return $this->fname;
  67         }
  68 }
  69
  70 /** @deprecated class alias since 1.42 */
  71 class_alias( AutoCommitUpdate::class, 'AutoCommitUpdate' );