From 0e5e02c9858076fe504f8c6ffc156d7cffc72582 Mon Sep 17 00:00:00 2001
From: Tim Starling <tstarling@wikimedia.org>
Date: Tue, 23 Sep 2014 15:27:13 +1000
Subject: [PATCH] Add a process cache for fetchLanguageNames

Since it is slow and is called many times when articles with lots of
interlanguage links are viewed.

Change-Id: Ib826ea6f1c105ffd43e456fb1c0c3b8aa6d8e391
---
 languages/Language.php | 38 +++++++++++++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/languages/Language.php b/languages/Language.php
index c889417cf1..bf2e3a399b 100644
--- a/languages/Language.php
+++ b/languages/Language.php
@@ -143,6 +143,12 @@ class Language {
 	 */
 	static private $fallbackLanguageCache = array();
 
+	/**
+	 * Cache for language names
+	 * @var MapCacheLRU|null
+	 */
+	static private $languageNameCache;
+
 	/**
 	 * Get a cached or new language object for a given language code
 	 * @param string $code
@@ -846,11 +852,36 @@ class Language {
 	 * @since 1.20
 	 */
 	public static function fetchLanguageNames( $inLanguage = null, $include = 'mw' ) {
+		wfProfileIn( __METHOD__ );
+		$cacheKey = $inLanguage === null ? 'null' : $inLanguage;
+		$cacheKey .= ":$include";
+		if ( self::$languageNameCache === null ) {
+			self::$languageNameCache = new MapCacheLRU( 20 );
+		}
+		if ( self::$languageNameCache->has( $cacheKey ) ) {
+			$ret = self::$languageNameCache->get( $cacheKey );
+		} else {
+			$ret = self::fetchLanguageNamesUncached( $inLanguage, $include );
+			self::$languageNameCache->set( $cacheKey, $ret );
+		}
+		wfProfileOut( __METHOD__ );
+		return $ret;
+	}
+
+	/**
+	 * Uncached helper for fetchLanguageNames
+	 * @param null|string $inLanguage Code of language in which to return the names
+	 *		Use null for autonyms (native names)
+	 * @param string $include One of:
+	 *		'all' all available languages
+	 *		'mw' only if the language is defined in MediaWiki or wgExtraLanguageNames (default)
+	 *		'mwfile' only if the language is in 'mw' *and* has a message file
+	 * @return array Language code => language name
+	 */
+	private static function fetchLanguageNamesUncached( $inLanguage = null, $include = 'mw' ) {
 		global $wgExtraLanguageNames;
 		static $coreLanguageNames;
 
-		wfProfileIn( __METHOD__ );
-
 		if ( $coreLanguageNames === null ) {
 			global $IP;
 			include "$IP/languages/Names.php";
@@ -878,7 +909,6 @@ class Language {
 		}
 
 		if ( $include === 'all' ) {
-			wfProfileOut( __METHOD__ );
 			return $names;
 		}
 
@@ -900,12 +930,10 @@ class Language {
 				}
 			}
 
-			wfProfileOut( __METHOD__ );
 			return $namesMwFile;
 		}
 
 		# 'mw' option; default if it's not one of the other two options (all/mwfile)
-		wfProfileOut( __METHOD__ );
 		return $returnMw;
 	}
 
-- 
2.20.1