LinksUpdate: Add functions returning changed page properties

This adds getAddedProperties and getRemovedProperties functions
to LinksUpdate. They are available only after the update, so for
extensions in the LinksUpdateComplete hook. This is useful for
example if an extension caches a page property; if the property
gets changed it may want to purge the cache.

This is similar to the getAddedLinks and getRemovedLinks
functions.

Change-Id: I0c73b3d181f32502da75687857ae9aeff731f559

diff --git a/includes/deferred/LinksUpdate.php b/includes/deferred/LinksUpdate.php
index 5e02c5c..ec7360e 100644 (file)
--- a/includes/deferred/LinksUpdate.php
+++ b/includes/deferred/LinksUpdate.php
@@ -79,6 +79,16 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
         */
        private $linkDeletions = null;
 
+       /**
+        * @var null|array Added properties if calculated.
+        */
+       private $propertyInsertions = null;
+
+       /**
+        * @var null|array Deleted properties if calculated.
+        */
+       private $propertyDeletions = null;
+
        /**
         * @var User|null
         */
@@ -234,12 +244,13 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 
                # Page properties
                $existing = $this->getExistingProperties();
-               $propertiesDeletes = $this->getPropertyDeletions( $existing );
-               $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
+               $this->propertyDeletions = $this->getPropertyDeletions( $existing );
+               $this->incrTableUpdate( 'page_props', 'pp', $this->propertyDeletions,
                        $this->getPropertyInsertions( $existing ) );
 
                # Invalidate the necessary pages
-               $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
+               $this->propertyInsertions = array_diff_assoc( $this->mProperties, $existing );
+               $changed = $this->propertyDeletions + $this->propertyInsertions;
                $this->invalidateProperties( $changed );
 
                # Refresh links of all pages including this page
@@ -1016,6 +1027,26 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
                return $result;
        }
 
+       /**
+        * Fetch page properties added by this LinksUpdate.
+        * Only available after the update is complete.
+        * @since 1.28
+        * @return null|array
+        */
+       public function getAddedProperties() {
+               return $this->propertyInsertions;
+       }
+
+       /**
+        * Fetch page properties removed by this LinksUpdate.
+        * Only available after the update is complete.
+        * @since 1.28
+        * @return null|array
+        */
+       public function getRemovedProperties() {
+               return $this->propertyDeletions;
+       }
+
        /**
         * Update links table freshness
         */