includes/deferred/MWCallableUpdate.php

   1 <?php
   2
   3 namespace MediaWiki\Deferred;
   4
   5 use Closure;
   6 use Wikimedia\Rdbms\IDatabase;
   7 use Wikimedia\Rdbms\Platform\ISQLPlatform;
   8
   9 /**
  10  * DeferrableUpdate for closure/callable
  11  *
  12  * @internal Use DeferredUpdates::addCallableUpdate instead
  13  */
  14 class MWCallableUpdate
  15         implements DeferrableUpdate, DeferrableCallback, TransactionRoundAwareUpdate
  16 {
  17         /** @var callable|null Callback, or null if it was cancelled */
  18         private $callback;
  19         /** @var string Calling method name */
  20         private $fname;
  21         /** @var int One of the class TRX_ROUND_* constants */
  22         private $trxRoundRequirement = self::TRX_ROUND_PRESENT;
  23
  24         /**
  25          * @param callable $callback One of the following:
  26          *    - A Closure callback that takes the caller name as its argument
  27          *    - A non-Closure callback that takes no arguments
  28          * @param string $fname Calling method @phan-mandatory-param
  29          * @param IDatabase|IDatabase[] $dependeeDbws DB handles which might have pending writes
  30          *  upon which this update depends. If any of the handles already has an open transaction,
  31          *  a rollback thereof will cause this update to be cancelled (if it has not already run).
  32          *  [optional]
  33          */
  34         public function __construct(
  35                 callable $callback,
  36                 $fname = ISQLPlatform::CALLER_UNKNOWN,
  37                 $dependeeDbws = []
  38         ) {
  39                 $this->callback = $callback;
  40                 $this->fname = $fname;
  41
  42                 $dependeeDbws = is_array( $dependeeDbws ) ? $dependeeDbws : [ $dependeeDbws ];
  43                 foreach ( $dependeeDbws as $dbw ) {
  44                         if ( $dbw->trxLevel() ) {
  45                                 $dbw->onTransactionResolution( [ $this, 'cancelOnRollback' ], $fname );
  46                         }
  47                 }
  48         }
  49
  50         public function doUpdate() {
  51                 if ( $this->callback instanceof Closure ) {
  52                         ( $this->callback )( $this->fname );
  53                 } elseif ( $this->callback ) {
  54                         // For backwards-compatibility with [$classOrObject, 'func'] style callbacks
  55                         // where the function happened to already take an optional parameter.
  56                         ( $this->callback )();
  57                 }
  58         }
  59
  60         /**
  61          * @internal This method is public so that it works with onTransactionResolution()
  62          * @param int $trigger
  63          */
  64         public function cancelOnRollback( $trigger ) {
  65                 if ( $trigger === IDatabase::TRIGGER_ROLLBACK ) {
  66                         $this->callback = null;
  67                 }
  68         }
  69
  70         public function getOrigin() {
  71                 return $this->fname;
  72         }
  73
  74         /**
  75          * @param int $mode One of the class TRX_ROUND_* constants
  76          */
  77         public function setTransactionRoundRequirement( $mode ) {
  78                 $this->trxRoundRequirement = $mode;
  79         }
  80
  81         public function getTransactionRoundRequirement() {
  82                 return $this->trxRoundRequirement;
  83         }
  84 }
  85
  86 /** @deprecated class alias since 1.42 */
  87 class_alias( MWCallableUpdate::class, 'MWCallableUpdate' );