includes/deferred/MergeableUpdate.php

   1 <?php
   2
   3 namespace MediaWiki\Deferred;
   4
   5 /**
   6  * Interface that deferrable updates can implement to signal that updates can be combined.
   7  *
   8  * DeferredUpdates uses this to merge all pending updates of PHP class into a single update
   9  * by calling merge(). Note that upon merge(), the combined update goes to the back of the FIFO
  10  * queue so that such updates occur after related non-mergeable deferred updates. For example,
  11  * suppose updates that purge URL objects all use the same MergeableUpdate class, updates that
  12  * delete URL objects use a different class, and the calling pattern is:
  13  *   - a) DeferredUpdates::addUpdate( $purgeCdnUrlsA );
  14  *   - b) DeferredUpdates::addUpdate( $deleteContentUrlsB );
  15  *   - c) DeferredUpdates::addUpdate( $purgeCdnUrlsB )
  16  *
  17  * In this case, purges for urls A and B will all happen after the $deleteContentUrlsB update.
  18  *
  19  * @stable to implement
  20  *
  21  * @since 1.27
  22  */
  23 interface MergeableUpdate extends DeferrableUpdate {
  24         /**
  25          * Merge this enqueued update with a new MergeableUpdate of the same qualified class name
  26          *
  27          * @param MergeableUpdate $update The new update (having the same class)
  28          */
  29         public function merge( MergeableUpdate $update );
  30 }
  31
  32 /** @deprecated class alias since 1.42 */
  33 class_alias( MergeableUpdate::class, 'MergeableUpdate' );