From: Aaron Schulz <aschulz@wikimedia.org>
Date: Thu, 20 Jul 2017 05:05:18 +0000 (-0700)
Subject: Refactor LoadBalancer::setDomainPrefix() to use forEachOpen* method
X-Git-Tag: 1.31.0-rc.0~2650^2
X-Git-Url: http://git.cyclocoop.org/%24image?a=commitdiff_plain;h=328365dcc8ce1cfa3b3818a95ef6994fbd034342;p=lhc%2Fweb%2Fwiklou.git

Refactor LoadBalancer::setDomainPrefix() to use forEachOpen* method

This makes the code more consistent with the other class methods
that iterate over connection handles and less fragile.

Change-Id: Ie2d8efb80a66a5c87b5b3edd64cb6bc4268fa911
---

diff --git a/includes/libs/rdbms/loadbalancer/LoadBalancer.php b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
index 677a69f5ff..72217da7d9 100644
--- a/includes/libs/rdbms/loadbalancer/LoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
@@ -1625,13 +1625,19 @@ class LoadBalancer implements ILoadBalancer {
 	}
 
 	public function setDomainPrefix( $prefix ) {
-		if ( $this->mConns[self::KEY_FOREIGN_INUSE] ) {
-			// Do not switch connections to explicit foreign domains unless marked as free
-			$domains = [];
-			foreach ( $this->mConns[self::KEY_FOREIGN_INUSE] as $i => $connsByDomain ) {
-				$domains = array_merge( $domains, array_keys( $connsByDomain ) );
+		// Find connections to explicit foreign domains still marked as in-use...
+		$domainsInUse = [];
+		$this->forEachOpenConnection( function ( IDatabase $conn ) use ( &$domainsInUse ) {
+			// Once reuseConnection() is called on a handle, its reference count goes from 1 to 0.
+			// Until then, it is still in use by the caller (explicitly or via DBConnRef scope).
+			if ( $conn->getLBInfo( 'foreignPoolRefCount' ) > 0 ) {
+				$domainsInUse[] = $conn->getDomainID();
 			}
-			$domains = implode( ', ', $domains );
+		} );
+
+		// Do not switch connections to explicit foreign domains unless marked as safe
+		if ( $domainsInUse ) {
+			$domains = implode( ', ', $domainsInUse );
 			throw new DBUnexpectedError( null,
 				"Foreign domain connections are still in use ($domains)." );
 		}