From: Roan Kattouw <roan.kattouw@gmail.com>
Date: Fri, 19 Jul 2019 23:51:01 +0000 (-0700)
Subject: MessageCache: Fix isMainCacheable() logic for non-content languages
X-Git-Tag: 1.34.0-rc.0~933^2
X-Git-Url: http://git.cyclocoop.org/%7B%24admin_url%7Dcompta/comptes/journal.php?a=commitdiff_plain;ds=sidebyside;h=bcb6b9d0eb0656690af2dbdca0ae67d4bf73147b;p=lhc%2Fweb%2Fwiklou.git

MessageCache: Fix isMainCacheable() logic for non-content languages

The way isMainCacheable() was used, it always returned false in
non-content languages, because it would try to find strings like
'hidetoc/fr' in the array of message keys (which contains strings like
'hidetoc').

The consequence of this was that MessageCache would check the database
for a MediaWiki:hidetoc/fr page even if it already knew that that page
didn't exist. This is a substantial performance hit when requesting lots
of messages, like when building version hashes for ResourceLoader's
startup module.

Follows-up 4fc5ba8bf83102b02.

Bug: T228555
Change-Id: I20433175ca919acc1c995f4a9cd50ca53afcdd02
---

diff --git a/includes/cache/MessageCache.php b/includes/cache/MessageCache.php
index b0716b18b3..a8bcfc6b44 100644
--- a/includes/cache/MessageCache.php
+++ b/includes/cache/MessageCache.php
@@ -525,9 +525,8 @@ class MessageCache {
 			__METHOD__ . "($code)-big"
 		);
 		foreach ( $res as $row ) {
-			$name = $this->contLang->lcfirst( $row->page_title );
 			// Include entries/stubs for all keys in $mostused in adaptive mode
-			if ( $wgAdaptiveMessageCache || $this->isMainCacheable( $name, $overridable ) ) {
+			if ( $wgAdaptiveMessageCache || $this->isMainCacheable( $row->page_title, $overridable ) ) {
 				$cache[$row->page_title] = '!TOO BIG';
 			}
 			// At least include revision ID so page changes are reflected in the hash
@@ -549,9 +548,8 @@ class MessageCache {
 			$revQuery['joins']
 		);
 		foreach ( $res as $row ) {
-			$name = $this->contLang->lcfirst( $row->page_title );
 			// Include entries/stubs for all keys in $mostused in adaptive mode
-			if ( $wgAdaptiveMessageCache || $this->isMainCacheable( $name, $overridable ) ) {
+			if ( $wgAdaptiveMessageCache || $this->isMainCacheable( $row->page_title, $overridable ) ) {
 				try {
 					$rev = $revisionStore->newRevisionFromRow( $row );
 					$content = $rev->getContent( MediaWiki\Revision\SlotRecord::MAIN );
@@ -592,14 +590,17 @@ class MessageCache {
 	}
 
 	/**
-	 * @param string $name Message name with lowercase first letter
+	 * @param string $name Message name (possibly with /code suffix)
 	 * @param array $overridable Map of (key => unused) for software-defined messages
 	 * @return bool
 	 */
 	private function isMainCacheable( $name, array $overridable ) {
+		// Convert first letter to lowercase, and strip /code suffix
+		$name = $this->contLang->lcfirst( $name );
+		$msg = preg_replace( '/\/[a-z0-9-]{2,}$/', '', $name );
 		// Include common conversion table pages. This also avoids problems with
 		// Installer::parse() bailing out due to disallowed DB queries (T207979).
-		return ( isset( $overridable[$name] ) || strpos( $name, 'conversiontable/' ) === 0 );
+		return ( isset( $overridable[$msg] ) || strpos( $name, 'conversiontable/' ) === 0 );
 	}
 
 	/**
@@ -1069,8 +1070,7 @@ class MessageCache {
 			);
 		} else {
 			// Message page either does not exist or does not override a software message
-			$name = $this->contLang->lcfirst( $title );
-			if ( !$this->isMainCacheable( $name, $this->overridable ) ) {
+			if ( !$this->isMainCacheable( $title, $this->overridable ) ) {
 				// Message page does not override any software-defined message. A custom
 				// message might be defined to have content or settings specific to the wiki.
 				// Load the message page, utilizing the individual message cache as needed.
diff --git a/tests/phpunit/includes/cache/MessageCacheTest.php b/tests/phpunit/includes/cache/MessageCacheTest.php
index 2fa662b88b..35dacac598 100644
--- a/tests/phpunit/includes/cache/MessageCacheTest.php
+++ b/tests/phpunit/includes/cache/MessageCacheTest.php
@@ -204,7 +204,7 @@ class MessageCacheTest extends MediaWikiLangTestCase {
 		];
 	}
 
-	public function testNoDBAccess() {
+	public function testNoDBAccessContentLanguage() {
 		global $wgContLanguageCode;
 
 		$dbr = wfGetDB( DB_REPLICA );
@@ -218,7 +218,22 @@ class MessageCacheTest extends MediaWikiLangTestCase {
 
 		$dbr->restoreFlags();
 
-		$this->assertEquals( 0, $dbr->trxLevel(), "No DB read queries" );
+		$this->assertEquals( 0, $dbr->trxLevel(), "No DB read queries (content language)" );
+	}
+
+	public function testNoDBAccessNonContentLanguage() {
+		$dbr = wfGetDB( DB_REPLICA );
+
+		MessageCache::singleton()->getMsgFromNamespace( 'allpages/nl', 'nl' );
+
+		$this->assertEquals( 0, $dbr->trxLevel() );
+		$dbr->setFlag( DBO_TRX, $dbr::REMEMBER_PRIOR ); // make queries trigger TRX
+
+		MessageCache::singleton()->getMsgFromNamespace( 'go/nl', 'nl' );
+
+		$dbr->restoreFlags();
+
+		$this->assertEquals( 0, $dbr->trxLevel(), "No DB read queries (non-content language)" );
 	}
 
 	/**