Merge "Make server index validity checks in LoadBalancer actually work"

[lhc/web/wiklou.git] / includes / libs / rdbms / loadbalancer / LoadBalancer.php

diff --git a/includes/libs/rdbms/loadbalancer/LoadBalancer.php b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
index 66e4fcf..083dcd6 100644 (file)
--- a/includes/libs/rdbms/loadbalancer/LoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
@@ -105,10 +105,9 @@ class LoadBalancer implements ILoadBalancer {
 
        /** @var integer Warn when this many connection are held */
        const CONN_HELD_WARN_THRESHOLD = 10;
+
        /** @var integer Default 'max lag' when unspecified */
        const MAX_LAG_DEFAULT = 10;
-       /** @var integer Max time to wait for a replica DB to catch up (e.g. ChronologyProtector) */
-       const POS_WAIT_TIMEOUT = 10;
        /** @var integer Seconds to cache master server read-only status */
        const TTL_CACHE_READONLY = 5;
 
@@ -130,9 +129,7 @@ class LoadBalancer implements ILoadBalancer {
                        $this->localDomainIdAlias = $this->localDomain->getDatabase();
                }
 
-               $this->mWaitTimeout = isset( $params['waitTimeout'] )
-                       ? $params['waitTimeout']
-                       : self::POS_WAIT_TIMEOUT;
+               $this->mWaitTimeout = isset( $params['waitTimeout'] ) ? $params['waitTimeout'] : 10;
 
                $this->mReadIndex = -1;
                $this->mConns = [
@@ -477,7 +474,7 @@ class LoadBalancer implements ILoadBalancer {
 
                                return false;
                        } else {
-                               $conn = $this->openConnection( $index, '' );
+                               $conn = $this->openConnection( $index, self::DOMAIN_ANY );
                                if ( !$conn ) {
                                        $this->replLogger->warning( __METHOD__ . ": failed to connect to $server" );
 
@@ -614,6 +611,10 @@ class LoadBalancer implements ILoadBalancer {
                        return;
                }
 
+               if ( $this->disabled ) {
+                       return; // DBConnRef handle probably survived longer than the LoadBalancer
+               }
+
                $domain = $conn->getDomainID();
                if ( !isset( $this->mConns['foreignUsed'][$serverIndex][$domain] ) ) {
                        throw new InvalidArgumentException( __METHOD__ .
@@ -666,6 +667,10 @@ class LoadBalancer implements ILoadBalancer {
                } elseif ( isset( $this->mConns['local'][$i][0] ) ) {
                        $conn = $this->mConns['local'][$i][0];
                } else {
+                       if ( !isset( $this->mServers[$i] ) || !is_array( $this->mServers[$i] ) ) {
+                               throw new InvalidArgumentException( "No server with index '$i'." );
+                       }
+                       // Open a new connection
                        $server = $this->mServers[$i];
                        $server['serverIndex'] = $i;
                        $conn = $this->reallyOpenConnection( $server, false );
@@ -746,6 +751,9 @@ class LoadBalancer implements ILoadBalancer {
                                        ": reusing free connection from $oldDomain for $domain" );
                        }
                } else {
+                       if ( !isset( $this->mServers[$i] ) || !is_array( $this->mServers[$i] ) ) {
+                               throw new InvalidArgumentException( "No server with index '$i'." );
+                       }
                        // Open a new connection
                        $server = $this->mServers[$i];
                        $server['serverIndex'] = $i;
@@ -798,17 +806,11 @@ class LoadBalancer implements ILoadBalancer {
         * @throws DBAccessError
         * @throws InvalidArgumentException
         */
-       protected function reallyOpenConnection( $server, $dbNameOverride = false ) {
+       protected function reallyOpenConnection( array $server, $dbNameOverride = false ) {
                if ( $this->disabled ) {
                        throw new DBAccessError();
                }
 
-               if ( !is_array( $server ) ) {
-                       throw new InvalidArgumentException(
-                               'You must update your load-balancing configuration. ' .
-                               'See DefaultSettings.php entry for $wgDBservers.' );
-               }
-
                if ( $dbNameOverride !== false ) {
                        $server['dbname'] = $dbNameOverride;
                }
@@ -1450,10 +1452,15 @@ class LoadBalancer implements ILoadBalancer {
                }
 
                if ( !$pos ) {
-                       // Get the current master position
-                       $dbw = $this->getConnection( self::DB_MASTER );
-                       $pos = $dbw->getMasterPos();
-                       $this->reuseConnection( $dbw );
+                       // Get the current master position, opening a connection if needed
+                       $masterConn = $this->getAnyOpenConnection( $this->getWriterIndex() );
+                       if ( $masterConn ) {
+                               $pos = $masterConn->getMasterPos();
+                       } else {
+                               $masterConn = $this->openConnection( $this->getWriterIndex(), self::DOMAIN_ANY );
+                               $pos = $masterConn->getMasterPos();
+                               $this->closeConnection( $masterConn );
+                       }
                }
 
                if ( $pos instanceof DBMasterPos ) {
@@ -1533,6 +1540,6 @@ class LoadBalancer implements ILoadBalancer {
 
        function __destruct() {
                // Avoid connection leaks for sanity
-               $this->closeAll();
+               $this->disable();
        }
 }