From: Aaron Schulz <aschulz@wikimedia.org>
Date: Sat, 22 Jul 2017 02:17:40 +0000 (-0700)
Subject: Check headers_sent() before sending cpPosTime headers
X-Git-Tag: 1.31.0-rc.0~2635^2
X-Git-Url: http://git.cyclocoop.org/%24self?a=commitdiff_plain;h=6b982c7978b7a9b66855211d36b7901b3c7ca257;p=lhc%2Fweb%2Fwiklou.git

Check headers_sent() before sending cpPosTime headers

Some entry points stream output and flush their own headers.
This avoids "headers already send" warnings in some cases.

Change-Id: Ifb232d4575486749bbbccba88f3f688972fe9c20
---

diff --git a/includes/MediaWiki.php b/includes/MediaWiki.php
index 4df4d76f53..4e471844d8 100644
--- a/includes/MediaWiki.php
+++ b/includes/MediaWiki.php
@@ -609,6 +609,7 @@ class MediaWiki {
 			$lbFactory->hasOrMadeRecentMasterChanges( INF )
 		) ? self::getUrlDomainDistance( $output->getRedirect(), $context ) : false;
 
+		$allowHeaders = !( $output->isDisabled() || headers_sent() );
 		if ( $urlDomainDistance === 'local' || $urlDomainDistance === 'remote' ) {
 			// OutputPage::output() will be fast; $postCommitWork will not be useful for
 			// masking the latency of syncing DB positions accross all datacenters synchronously.
@@ -616,7 +617,7 @@ class MediaWiki {
 			$flags = $lbFactory::SHUTDOWN_CHRONPROT_ASYNC;
 			$cpPosTime = microtime( true );
 			// Client's next request should see 1+ positions with this DBMasterPos::asOf() time
-			if ( $urlDomainDistance === 'local' ) {
+			if ( $urlDomainDistance === 'local' && $allowHeaders ) {
 				// Client will stay on this domain, so set an unobtrusive cookie
 				$expires = time() + ChronologyProtector::POSITION_TTL;
 				$options = [ 'prefix' => '' ];
@@ -633,7 +634,7 @@ class MediaWiki {
 			// OutputPage::output() is fairly slow; run it in $postCommitWork to mask
 			// the latency of syncing DB positions accross all datacenters synchronously
 			$flags = $lbFactory::SHUTDOWN_CHRONPROT_SYNC;
-			if ( $lbFactory->hasOrMadeRecentMasterChanges( INF ) ) {
+			if ( $lbFactory->hasOrMadeRecentMasterChanges( INF ) && $allowHeaders ) {
 				$cpPosTime = microtime( true );
 				// Set a cookie in case the DB position store cannot sync accross datacenters.
 				// This will at least cover the common case of the user staying on the domain.