From c45cfc9233b6969a7d03467ee2241be89f1b79de Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@users.mediawiki.org>
Date: Fri, 24 Jul 2009 20:01:23 +0000
Subject: [PATCH] * (bug 19849) Custom X-Vary-Options header now disabled
 unless $wgUseXVO is set

---
 RELEASE-NOTES                | 1 +
 includes/DefaultSettings.php | 3 +++
 includes/OutputPage.php      | 8 +++++---
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index e389e0278b..1cf190a457 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -327,6 +327,7 @@ this. Was used when mwEmbed was going to be an extension.
   when using long urls
 * The display of the language list on the preferences is more comply with the 
   BCP 47 standards.
+* (bug 19849) Custom X-Vary-Options header now disabled unless $wgUseXVO is set
 
 == API changes in 1.16 ==
 
diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index f2e85dfe4c..a25af3553e 100644
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -1690,6 +1690,9 @@ $wgUseSquid = false;
 /** If you run Squid3 with ESI support, enable this (default:false): */
 $wgUseESI = false;
 
+/** Send X-Vary-Options header for better caching (requires patched Squid) */
+$wgUseXVO = false;
+
 /** Internal server name as known to Squid, if different */
 # $wgInternalServer = 'http://yourinternal.tld:8000';
 $wgInternalServer = $wgServer;
diff --git a/includes/OutputPage.php b/includes/OutputPage.php
index 8d80657886..93318e68c2 100644
--- a/includes/OutputPage.php
+++ b/includes/OutputPage.php
@@ -977,7 +977,7 @@ class OutputPage {
 	}
 
 	public function sendCacheControl() {
-		global $wgUseSquid, $wgUseESI, $wgUseETag, $wgSquidMaxage, $wgRequest;
+		global $wgUseSquid, $wgUseESI, $wgUseETag, $wgSquidMaxage, $wgRequest, $wgUseXVO;
 
 		$response = $wgRequest->response();
 		if ($wgUseETag && $this->mETag)
@@ -987,8 +987,10 @@ class OutputPage {
 		# maintain different caches for logged-in users and non-logged in ones
 		$response->header( 'Vary: Accept-Encoding, Cookie' );
 
-		# Add an X-Vary-Options header for Squid with Wikimedia patches
-		$response->header( $this->getXVO() );
+		if ( $wgUseXVO ) {
+			# Add an X-Vary-Options header for Squid with Wikimedia patches
+			$response->header( $this->getXVO() );
+		}
 
 		if( !$this->uncacheableBecauseRequestVars() && $this->mEnableClientCache ) {
 			if( $wgUseSquid && session_id() == '' &&
-- 
2.20.1