includes/deferred/AtomicSectionUpdate.php

   1 <?php
   2
   3 namespace MediaWiki\Deferred;
   4
   5 use Wikimedia\Rdbms\IDatabase;
   6
   7 /**
   8  * Deferrable Update for closure/callback updates via IDatabase::doAtomicSection()
   9  * @since 1.27
  10  */
  11 class AtomicSectionUpdate 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          * @see IDatabase::doAtomicSection()
  21          * @param IDatabase $dbw DB handle; update aborts if a transaction now this rolls back
  22          * @param string $fname Caller name (usually __METHOD__)
  23          * @param callable $callback
  24          * @param IDatabase[] $conns Cancel the update if a DB transaction 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                         $this->dbw->doAtomicSection( $this->fname, $this->callback );
  42                 }
  43         }
  44
  45         /**
  46          * @internal This method is public so that it works with onTransactionResolution()
  47          * @param int $trigger
  48          */
  49         public function cancelOnRollback( $trigger ) {
  50                 if ( $trigger === IDatabase::TRIGGER_ROLLBACK ) {
  51                         $this->callback = null;
  52                 }
  53         }
  54
  55         public function getOrigin() {
  56                 return $this->fname;
  57         }
  58 }
  59
  60 /** @deprecated class alias since 1.42 */
  61 class_alias( AtomicSectionUpdate::class, 'AtomicSectionUpdate' );