From e458290d7cd318016d706681c38b98f772b23fc3 Mon Sep 17 00:00:00 2001
From: Alex Monk <krenair@gmail.com>
Date: Sun, 17 Nov 2013 17:30:42 +0000
Subject: [PATCH] Cache VCS commit id/date text on Special:Version

So Special:Version works on beta.wmflabs.org again

Bug: 53335
Change-Id: I5a5b23a73974aba2322bf69f534e8aa8b60741db
---
 includes/specials/SpecialVersion.php | 52 +++++++++++++++++++++-------
 1 file changed, 40 insertions(+), 12 deletions(-)

diff --git a/includes/specials/SpecialVersion.php b/includes/specials/SpecialVersion.php
index c8add014a6..5c3f509895 100644
--- a/includes/specials/SpecialVersion.php
+++ b/includes/specials/SpecialVersion.php
@@ -31,6 +31,11 @@
 class SpecialVersion extends SpecialPage {
 	protected $firstExtOpened = false;
 
+	/**
+	 * Stores the current rev id/SHA hash of MediaWiki core
+	 */
+	protected $coreId = '';
+
 	protected static $extensionTypes = false;
 
 	protected static $viewvcUrls = array(
@@ -616,20 +621,43 @@ class SpecialVersion extends SpecialPage {
 		}
 
 		if ( isset( $extension['path'] ) ) {
-			$extensionPath = dirname( $extension['path'] );
-			$gitInfo = new GitInfo( $extensionPath );
-			$vcsVersion = $gitInfo->getHeadSHA1();
-			if ( $vcsVersion !== false ) {
-				$vcsVersion = substr( $vcsVersion, 0, 7 );
-				$vcsLink = $gitInfo->getHeadViewUrl();
-				$vcsDate = $gitInfo->getHeadCommitDate();
-			} else {
-				$svnInfo = self::getSvnInfo( $extensionPath );
-				if ( $svnInfo !== false ) {
-					$vcsVersion = $this->msg( 'version-svn-revision', $svnInfo['checkout-rev'] )->text();
-					$vcsLink = isset( $svnInfo['viewvc-url'] ) ? $svnInfo['viewvc-url'] : '';
+			global $IP;
+			if ( $this->coreId == '' ) {
+				wfDebug( 'Looking up core head id' );
+				$coreHeadSHA1 = self::getGitHeadSha1( $IP );
+				if ( $coreHeadSHA1 ) {
+					$this->coreId = $coreHeadSHA1;
+				} else {
+					$svnInfo = self::getSvnInfo( $IP );
+					if ( $svnInfo !== false ) {
+						$this->coreId = $svnInfo['checkout-rev'];
+					}
 				}
 			}
+			$cache = wfGetCache( CACHE_ANYTHING );
+			$memcKey = wfMemcKey( 'specialversion-ext-version-text', $extension['path'], $this->coreId );
+			list( $vcsVersion, $vcsLink, $vcsDate ) = $cache->get( $memcKey );
+
+			if ( !$vcsVersion ) {
+				wfDebug( "Getting VCS info for extension $extensionName" );
+				$extensionPath = dirname( $extension['path'] );
+				$gitInfo = new GitInfo( $extensionPath );
+				$vcsVersion = $gitInfo->getHeadSHA1();
+				if ( $vcsVersion !== false ) {
+					$vcsVersion = substr( $vcsVersion, 0, 7 );
+					$vcsLink = $gitInfo->getHeadViewUrl();
+					$vcsDate = $gitInfo->getHeadCommitDate();
+				} else {
+					$svnInfo = self::getSvnInfo( $extensionPath );
+					if ( $svnInfo !== false ) {
+						$vcsVersion = $this->msg( 'version-svn-revision', $svnInfo['checkout-rev'] )->text();
+						$vcsLink = isset( $svnInfo['viewvc-url'] ) ? $svnInfo['viewvc-url'] : '';
+					}
+				}
+				$cache->set( $memcKey, array( $vcsVersion, $vcsLink, $vcsDate ), 60 * 60 * 24 );
+			} else {
+				wfDebug( "Pulled VCS info for extension $extensionName from cache" );
+			}
 		}
 
 		$versionString = Html::rawElement(
-- 
2.20.1