includes/deferred/AutoCommitUpdate.php

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