From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 23 Jan 2019 19:32:18 +0000 (-0800)
Subject: rdbms: make safeWaitForMasterPos() handle master connection failure
X-Git-Tag: 1.34.0-rc.0~2715
X-Git-Url: https://git.cyclocoop.org/%242?a=commitdiff_plain;h=7f3483e51495a9fc8b2dbfc95b02afbb9b9f5bc9;p=lhc%2Fweb%2Fwiklou.git

rdbms: make safeWaitForMasterPos() handle master connection failure

Previously, in such cases where a master connection was needed
and could not be acquired, a fatal error would occur. Instead,
throw a DBReplicationWaitError exception.

Also removed a redundant documentation block for the method.

Change-Id: Ide3015d57673df0876daf265a0182fe41004052d
---

diff --git a/includes/libs/rdbms/loadbalancer/LoadBalancer.php b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
index f2e4e3d7d1..9e4b15ff79 100644
--- a/includes/libs/rdbms/loadbalancer/LoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
@@ -1842,12 +1842,6 @@ class LoadBalancer implements ILoadBalancer {
 		}
 	}
 
-	/**
-	 * @param IDatabase $conn
-	 * @param DBMasterPos|bool $pos
-	 * @param int|null $timeout
-	 * @return bool
-	 */
 	public function safeWaitForMasterPos( IDatabase $conn, $pos = false, $timeout = null ) {
 		$timeout = max( 1, $timeout ?: $this->waitTimeout );
 
@@ -1862,6 +1856,12 @@ class LoadBalancer implements ILoadBalancer {
 				$pos = $masterConn->getMasterPos();
 			} else {
 				$masterConn = $this->openConnection( $this->getWriterIndex(), self::DOMAIN_ANY );
+				if ( !$masterConn ) {
+					throw new DBReplicationWaitError(
+						null,
+						"Could not obtain a master database connection to get the position"
+					);
+				}
 				$pos = $masterConn->getMasterPos();
 				$this->closeConnection( $masterConn );
 			}