resourceloader: Preload WikiModule::getTitleInfo() in batches

Test plan:
* Request load.php?modules=startup&only=scripts
* Debug log receives 1 entry in the 'queries' channel from
  ResourceLoaderWikiModule, and it comes from preloadTitleInfo.

Bug: T46362
Change-Id: I82e215745af6b8446cd69282b2c943afbbd45065

diff --git a/includes/resourceloader/ResourceLoader.php b/includes/resourceloader/ResourceLoader.php
index 3cb30bc..ad1ed49 100644 (file)
--- a/includes/resourceloader/ResourceLoader.php
+++ b/includes/resourceloader/ResourceLoader.php
@@ -140,6 +140,9 @@ class ResourceLoader implements LoggerAwareInterface {
                        }
                }
 
+               // Batched version of ResourceLoaderWikiModule::getTitleInfo
+               ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $moduleNames );
+
                // Prime in-object cache for message blobs for modules with messages
                $modules = [];
                foreach ( $moduleNames as $name ) {

diff --git a/includes/resourceloader/ResourceLoaderWikiModule.php b/includes/resourceloader/ResourceLoaderWikiModule.php
index 8033843..5580306 100644 (file)
--- a/includes/resourceloader/ResourceLoaderWikiModule.php
+++ b/includes/resourceloader/ResourceLoaderWikiModule.php
@@ -276,6 +276,10 @@ class ResourceLoaderWikiModule extends ResourceLoaderModule {
                return count( $revisions ) === 0;
        }
 
+       private function setTitleInfo( $key, array $titleInfo ) {
+               $this->titleInfo[$key] = $titleInfo;
+       }
+
        /**
         * Get the information about the wiki pages for a given context.
         * @param ResourceLoaderContext $context
@@ -288,35 +292,77 @@ class ResourceLoaderWikiModule extends ResourceLoaderModule {
                        return [];
                }
 
-               $pages = $this->getPages( $context );
-               $key = implode( '|', array_keys( $pages ) );
+               $pageNames = array_keys( $this->getPages( $context ) );
+               sort( $pageNames );
+               $key = implode( '|', $pageNames );
                if ( !isset( $this->titleInfo[$key] ) ) {
-                       $this->titleInfo[$key] = [];
-                       $batch = new LinkBatch;
-                       foreach ( $pages as $titleText => $options ) {
-                               $batch->addObj( Title::newFromText( $titleText ) );
+                       $this->titleInfo[$key] = self::fetchTitleInfo( $dbr, $pageNames, __METHOD__ );
+               }
+               return $this->titleInfo[$key];
+       }
+
+       private static function fetchTitleInfo( IDatabase $db, array $pages, $fname = __METHOD__ ) {
+               $titleInfo = [];
+               $batch = new LinkBatch;
+               foreach ( $pages as $titleText ) {
+                       $batch->addObj( Title::newFromText( $titleText ) );
+               }
+               if ( !$batch->isEmpty() ) {
+                       $res = $db->select( 'page',
+                               // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
+                               [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
+                               $batch->constructSet( 'page', $db ),
+                               $fname
+                       );
+                       foreach ( $res as $row ) {
+                               // Avoid including ids or timestamps of revision/page tables so
+                               // that versions are not wasted
+                               $title = Title::makeTitle( $row->page_namespace, $row->page_title );
+                               $titleInfo[$title->getPrefixedText()] = [
+                                       'page_len' => $row->page_len,
+                                       'page_latest' => $row->page_latest,
+                                       'page_touched' => $row->page_touched,
+                               ];
                        }
+               }
+               return $titleInfo;
+       }
 
-                       if ( !$batch->isEmpty() ) {
-                               $res = $dbr->select( 'page',
-                                       // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
-                                       [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
-                                       $batch->constructSet( 'page', $dbr ),
-                                       __METHOD__
-                               );
-                               foreach ( $res as $row ) {
-                                       // Avoid including ids or timestamps of revision/page tables so
-                                       // that versions are not wasted
-                                       $title = Title::makeTitle( $row->page_namespace, $row->page_title );
-                                       $this->titleInfo[$key][$title->getPrefixedText()] = [
-                                               'page_len' => $row->page_len,
-                                               'page_latest' => $row->page_latest,
-                                               'page_touched' => $row->page_touched,
-                                       ];
+       /**
+        * @since 1.28
+        * @param ResourceLoaderContext $context
+        * @param IDatabase $db
+        * @param string[] $modules
+        */
+       public static function preloadTitleInfo(
+               ResourceLoaderContext $context, IDatabase $db, array $moduleNames
+       ) {
+               $rl = $context->getResourceLoader();
+               // getDB() can be overridden to point to a foreign database.
+               // For now, only preload local. In the future, we could preload by wikiID.
+               $allPages = [];
+               $wikiModules = [];
+               foreach ( $moduleNames as $name ) {
+                       $module = $rl->getModule( $name );
+                       if ( $module instanceof self ) {
+                               $mDB = $module->getDB();
+                               // Subclasses may disable getDB and implement getTitleInfo differently
+                               if ( $mDB && $mDB->getWikiID() === $db->getWikiID() ) {
+                                       $wikiModules[] = $module;
+                                       $allPages += $module->getPages( $context );
                                }
                        }
                }
-               return $this->titleInfo[$key];
+               $allInfo = self::fetchTitleInfo( $db, array_keys( $allPages ), __METHOD__ );
+               foreach ( $wikiModules as $module ) {
+                       $pages = $module->getPages( $context );
+                       $info = array_intersect_key( $allInfo, $pages );
+                       $pageNames = array_keys( $pages );
+                       sort( $pageNames );
+                       $key = implode( '|', $pageNames );
+                       $module->setTitleInfo( $key, $info );
+               }
+               return $allInfo;
        }
 
        /**