ParamValidator: Flag as unstable for 1.34

[lhc/web/wiklou.git] / includes / Category.php

diff --git a/includes/Category.php b/includes/Category.php
index 77f1212..229958a 100644 (file)
--- a/includes/Category.php
+++ b/includes/Category.php
@@ -41,6 +41,8 @@ class Category {
        const LOAD_ONLY = 0;
        const LAZY_INIT_ROW = 1;
 
+       const ROW_COUNT_SMALL = 100;
+
        private function __construct() {
        }
 
@@ -338,7 +340,7 @@ class Category {
                $dbw->lockForUpdate( 'category', [ 'cat_title' => $this->mName ], __METHOD__ );
 
                // Lock all the `categorylinks` records and gaps for this category;
-               // this is a separate query due to postgres/oracle limitations
+               // this is a separate query due to postgres limitations
                $dbw->selectRowCount(
                        [ 'categorylinks', 'page' ],
                        '*',
@@ -431,28 +433,57 @@ class Category {
         * @since 1.32
         */
        public function refreshCountsIfEmpty() {
+               return $this->refreshCountsIfSmall( 0 );
+       }
+
+       /**
+        * Call refreshCounts() if there are few entries in the categorylinks table
+        *
+        * Due to lock errors or other failures, the precomputed counts can get out of sync,
+        * making it hard to know when to delete the category row without checking the
+        * categorylinks table.
+        *
+        * This method will do a non-locking select first to reduce contention.
+        *
+        * @param int $maxSize Only refresh if there are this or less many backlinks
+        * @return bool Whether links were refreshed
+        * @since 1.34
+        */
+       public function refreshCountsIfSmall( $maxSize = self::ROW_COUNT_SMALL ) {
                $dbw = wfGetDB( DB_MASTER );
+               $dbw->startAtomic( __METHOD__ );
 
-               $hasLink = $dbw->selectField(
+               $typeOccurances = $dbw->selectFieldValues(
                        'categorylinks',
-                       '1',
+                       'cl_type',
                        [ 'cl_to' => $this->getName() ],
-                       __METHOD__
+                       __METHOD__,
+                       [ 'LIMIT' => $maxSize + 1 ]
                );
-               if ( !$hasLink ) {
-                       $this->refreshCounts(); // delete any category table entry
 
-                       return true;
+               if ( !$typeOccurances ) {
+                       $doRefresh = true; // delete any category table entry
+               } elseif ( count( $typeOccurances ) <= $maxSize ) {
+                       $countByType = array_count_values( $typeOccurances );
+                       $doRefresh = !$dbw->selectField(
+                               'category',
+                               '1',
+                               [
+                                       'cat_title' => $this->getName(),
+                                       'cat_pages' => $countByType['page'] ?? 0,
+                                       'cat_subcats' => $countByType['subcat'] ?? 0,
+                                       'cat_files' => $countByType['file'] ?? 0
+                               ],
+                               __METHOD__
+                       );
+               } else {
+                       $doRefresh = false; // category is too big
                }
 
-               $hasBadRow = $dbw->selectField(
-                       'category',
-                       '1',
-                       [ 'cat_title' => $this->getName(), 'cat_pages <= 0' ],
-                       __METHOD__
-               );
-               if ( $hasBadRow ) {
-                       $this->refreshCounts(); // clean up this row
+               $dbw->endAtomic( __METHOD__ );
+
+               if ( $doRefresh ) {
+                       $this->refreshCounts(); // update the row
 
                        return true;
                }