includes/jobqueue/aggregator/JobQueueAggregatorRedis.php

   1 <?php
   2 /**
   3  * Job queue aggregator code that uses PhpRedis.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Aaron Schulz
  22  */
  23
  24 /**
  25  * Class to handle tracking information about all queues using PhpRedis
  26  *
  27  * @ingroup JobQueue
  28  * @ingroup Redis
  29  * @since 1.21
  30  */
  31 class JobQueueAggregatorRedis extends JobQueueAggregator {
  32         /** @var RedisConnectionPool */
  33         protected $redisPool;
  34
  35         /** @var array List of Redis server addresses */
  36         protected $servers;
  37
  38         /**
  39          * @params include:
  40          *   - redisConfig  : An array of parameters to RedisConnectionPool::__construct().
  41          *   - redisServers : Array of server entries, the first being the primary and the
  42          *                    others being fallback servers. Each entry is either a hostname/port
  43          *                    combination or the absolute path of a UNIX socket.
  44          *                    If a hostname is specified but no port, the standard port number
  45          *                    6379 will be used. Required.
  46          * @param array $params
  47          */
  48         protected function __construct( array $params ) {
  49                 parent::__construct( $params );
  50                 $this->servers = isset( $params['redisServers'] )
  51                         ? $params['redisServers']
  52                         : array( $params['redisServer'] ); // b/c
  53                 $this->redisPool = RedisConnectionPool::singleton( $params['redisConfig'] );
  54         }
  55
  56         protected function doNotifyQueueEmpty( $wiki, $type ) {
  57                 $conn = $this->getConnection();
  58                 if ( !$conn ) {
  59                         return false;
  60                 }
  61                 try {
  62                         $conn->hDel( $this->getReadyQueueKey(), $this->encQueueName( $type, $wiki ) );
  63
  64                         return true;
  65                 } catch ( RedisException $e ) {
  66                         $this->handleException( $conn, $e );
  67
  68                         return false;
  69                 }
  70         }
  71
  72         protected function doNotifyQueueNonEmpty( $wiki, $type ) {
  73                 $conn = $this->getConnection();
  74                 if ( !$conn ) {
  75                         return false;
  76                 }
  77                 try {
  78                         $conn->hSet( $this->getReadyQueueKey(), $this->encQueueName( $type, $wiki ), time() );
  79
  80                         return true;
  81                 } catch ( RedisException $e ) {
  82                         $this->handleException( $conn, $e );
  83
  84                         return false;
  85                 }
  86         }
  87
  88         protected function doGetAllReadyWikiQueues() {
  89                 $conn = $this->getConnection();
  90                 if ( !$conn ) {
  91                         return array();
  92                 }
  93                 try {
  94                         $conn->multi( Redis::PIPELINE );
  95                         $conn->exists( $this->getReadyQueueKey() );
  96                         $conn->hGetAll( $this->getReadyQueueKey() );
  97                         list( $exists, $map ) = $conn->exec();
  98
  99                         if ( $exists ) { // cache hit
 100                                 $pendingDBs = array(); // (type => list of wikis)
 101                                 foreach ( $map as $key => $time ) {
 102                                         list( $type, $wiki ) = $this->dencQueueName( $key );
 103                                         $pendingDBs[$type][] = $wiki;
 104                                 }
 105                         } else { // cache miss
 106                                 // Avoid duplicated effort
 107                                 $rand = wfRandomString( 32 );
 108                                 $conn->multi( Redis::MULTI );
 109                                 $conn->setex( "{$rand}:lock", 3600, 1 );
 110                                 $conn->renamenx( "{$rand}:lock", $this->getReadyQueueKey() . ":lock" );
 111                                 if ( $conn->exec() !== array( true, true ) ) { // lock
 112                                         $conn->delete( "{$rand}:lock" );
 113                                         return array(); // already in progress
 114                                 }
 115
 116                                 $pendingDBs = $this->findPendingWikiQueues(); // (type => list of wikis)
 117
 118                                 $conn->delete( $this->getReadyQueueKey() . ":lock" ); // unlock
 119
 120                                 $now = time();
 121                                 $map = array();
 122                                 foreach ( $pendingDBs as $type => $wikis ) {
 123                                         foreach ( $wikis as $wiki ) {
 124                                                 $map[$this->encQueueName( $type, $wiki )] = $now;
 125                                         }
 126                                 }
 127                                 $conn->hMSet( $this->getReadyQueueKey(), $map );
 128                         }
 129
 130                         return $pendingDBs;
 131                 } catch ( RedisException $e ) {
 132                         $this->handleException( $conn, $e );
 133
 134                         return array();
 135                 }
 136         }
 137
 138         protected function doPurge() {
 139                 $conn = $this->getConnection();
 140                 if ( !$conn ) {
 141                         return false;
 142                 }
 143                 try {
 144                         $conn->delete( $this->getReadyQueueKey() );
 145                 } catch ( RedisException $e ) {
 146                         $this->handleException( $conn, $e );
 147
 148                         return false;
 149                 }
 150
 151                 return true;
 152         }
 153
 154         /**
 155          * Get a connection to the server that handles all sub-queues for this queue
 156          *
 157          * @return RedisConnRef|bool Returns false on failure
 158          * @throws MWException
 159          */
 160         protected function getConnection() {
 161                 $conn = false;
 162                 foreach ( $this->servers as $server ) {
 163                         $conn = $this->redisPool->getConnection( $server );
 164                         if ( $conn ) {
 165                                 break;
 166                         }
 167                 }
 168
 169                 return $conn;
 170         }
 171
 172         /**
 173          * @param RedisConnRef $conn
 174          * @param RedisException $e
 175          * @return void
 176          */
 177         protected function handleException( RedisConnRef $conn, $e ) {
 178                 $this->redisPool->handleError( $conn, $e );
 179         }
 180
 181         /**
 182          * @return string
 183          */
 184         private function getReadyQueueKey() {
 185                 return "jobqueue:aggregator:h-ready-queues:v1"; // global
 186         }
 187
 188         /**
 189          * @param string $type
 190          * @param string $wiki
 191          * @return string
 192          */
 193         private function encQueueName( $type, $wiki ) {
 194                 return rawurlencode( $type ) . '/' . rawurlencode( $wiki );
 195         }
 196
 197         /**
 198          * @param string $name
 199          * @return string
 200          */
 201         private function dencQueueName( $name ) {
 202                 list( $type, $wiki ) = explode( '/', $name, 2 );
 203
 204                 return array( rawurldecode( $type ), rawurldecode( $wiki ) );
 205         }
 206 }