Merge "Don't send email notifs to blocked users if $wgBlockDisablesLogin is true"

[lhc/web/wiklou.git] / includes / objectcache / RedisBagOStuff.php

diff --git a/includes/objectcache/RedisBagOStuff.php b/includes/objectcache/RedisBagOStuff.php
index b1be9d8..a9af9b1 100644 (file)
--- a/includes/objectcache/RedisBagOStuff.php
+++ b/includes/objectcache/RedisBagOStuff.php
@@ -25,6 +25,8 @@ class RedisBagOStuff extends BagOStuff {
        protected $redisPool;
        /** @var array List of server names */
        protected $servers;
+       /** @var array Map of (tag => server name) */
+       protected $serverTagMap;
        /** @var bool */
        protected $automaticFailover;
 
@@ -34,7 +36,8 @@ class RedisBagOStuff extends BagOStuff {
         *   - servers: An array of server names. A server name may be a hostname,
         *     a hostname/port combination or the absolute path of a UNIX socket.
         *     If a hostname is specified but no port, the standard port number
-        *     6379 will be used. Required.
+        *     6379 will be used. Arrays keys can be used to specify the tag to
+        *     hash on in place of the host/port. Required.
         *
         *   - connectTimeout: The timeout for new connections, in seconds. Optional,
         *     default is 1 second.
@@ -66,6 +69,10 @@ class RedisBagOStuff extends BagOStuff {
                $this->redisPool = RedisConnectionPool::singleton( $redisConf );
 
                $this->servers = $params['servers'];
+               foreach ( $this->servers as $key => $server ) {
+                       $this->serverTagMap[is_int( $key ) ? $server : $key] = $server;
+               }
+
                if ( isset( $params['automaticFailover'] ) ) {
                        $this->automaticFailover = $params['automaticFailover'];
                } else {
@@ -73,7 +80,7 @@ class RedisBagOStuff extends BagOStuff {
                }
        }
 
-       public function get( $key, &$casToken = null ) {
+       public function get( $key, &$casToken = null, $flags = 0 ) {
 
                list( $server, $conn ) = $this->getConnection( $key );
                if ( !$conn ) {
@@ -167,7 +174,7 @@ class RedisBagOStuff extends BagOStuff {
                return $result;
        }
 
-       public function getMulti( array $keys ) {
+       public function getMulti( array $keys, $flags = 0 ) {
 
                $batches = array();
                $conns = array();
@@ -257,8 +264,6 @@ class RedisBagOStuff extends BagOStuff {
                return $result;
        }
 
-
-
        public function add( $key, $value, $expiry = 0 ) {
 
                list( $server, $conn ) = $this->getConnection( $key );
@@ -270,6 +275,7 @@ class RedisBagOStuff extends BagOStuff {
                        if ( $expiry ) {
                                $conn->multi();
                                $conn->setnx( $key, $this->serialize( $value ) );
+                               // @FIXME: this always bumps the TTL; use Redis 2.8 or Lua
                                $conn->expire( $key, $expiry );
                                $result = ( $conn->exec() == array( true, true ) );
                        } else {
@@ -306,6 +312,7 @@ class RedisBagOStuff extends BagOStuff {
                        return null;
                }
                try {
+                       // @FIXME: on races, the key may have a 0 TTL
                        $result = $conn->incrBy( $key, $value );
                } catch ( RedisException $e ) {
                        $result = false;
@@ -315,6 +322,23 @@ class RedisBagOStuff extends BagOStuff {
                $this->logRequest( 'incr', $key, $server, $result );
                return $result;
        }
+
+       public function merge( $key, $callback, $exptime = 0, $attempts = 10 ) {
+               if ( !is_callable( $callback ) ) {
+                       throw new Exception( "Got invalid callback." );
+               }
+
+               return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
+       }
+
+       public function modifySimpleRelayEvent( array $event ) {
+               if ( array_key_exists( 'val', $event ) ) {
+                       $event['val'] = serialize( $event['val'] ); // this class uses PHP serialization
+               }
+
+               return $event;
+       }
+
        /**
         * @param mixed $data
         * @return string
@@ -339,26 +363,62 @@ class RedisBagOStuff extends BagOStuff {
         * @return array (server, RedisConnRef) or (false, false)
         */
        protected function getConnection( $key ) {
-               if ( count( $this->servers ) === 1 ) {
-                       $candidates = $this->servers;
-               } else {
-                       $candidates = $this->servers;
+               $candidates = array_keys( $this->serverTagMap );
+
+               if ( count( $this->servers ) > 1 ) {
                        ArrayUtils::consistentHashSort( $candidates, $key, '/' );
                        if ( !$this->automaticFailover ) {
                                $candidates = array_slice( $candidates, 0, 1 );
                        }
                }
 
-               foreach ( $candidates as $server ) {
+               while ( ( $tag = array_shift( $candidates ) ) !== null ) {
+                       $server = $this->serverTagMap[$tag];
                        $conn = $this->redisPool->getConnection( $server );
-                       if ( $conn ) {
-                               return array( $server, $conn );
+                       if ( !$conn ) {
+                               continue;
+                       }
+
+                       // If automatic failover is enabled, check that the server's link
+                       // to its master (if any) is up -- but only if there are other
+                       // viable candidates left to consider.
+                       if ( $this->automaticFailover && $candidates ) {
+                               try {
+                                       if ( $this->getMasterLinkStatus( $conn ) === 'down' ) {
+                                               // If the master cannot be reached, fail-over to the next server.
+                                               // If masters are in data-center A, and slaves in data-center B,
+                                               // this helps avoid the case were fail-over happens in A but not
+                                               // to the corresponding server in B (e.g. read/write mismatch).
+                                               continue;
+                                       }
+                               } catch ( RedisException $e ) {
+                                       // Server is not accepting commands
+                                       $this->handleException( $conn, $e );
+                                       continue;
+                               }
                        }
+
+                       return array( $server, $conn );
                }
+
                $this->setLastError( BagOStuff::ERR_UNREACHABLE );
+
                return array( false, false );
        }
 
+       /**
+        * Check the master link status of a Redis server that is configured as a slave.
+        * @param RedisConnRef $conn
+        * @return string|null Master link status (either 'up' or 'down'), or null
+        *  if the server is not a slave.
+        */
+       protected function getMasterLinkStatus( RedisConnRef $conn ) {
+               $info = $conn->info();
+               return isset( $info['master_link_status'] )
+                       ? $info['master_link_status']
+                       : null;
+       }
+
        /**
         * Log a fatal error
         * @param string $msg