includes/db/MWLBFactory.php

   1 <?php
   2 /**
   3  * Generator of database load balancing objects.
   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  * @ingroup Database
  22  */
  23
  24 use MediaWiki\Logger\LoggerFactory;
  25 use Wikimedia\Rdbms\LBFactory;
  26 use Wikimedia\Rdbms\DatabaseDomain;
  27
  28 /**
  29  * MediaWiki-specific class for generating database load balancers
  30  * @ingroup Database
  31  */
  32 abstract class MWLBFactory {
  33
  34         /** @var array Cache of already-logged deprecation messages */
  35         private static $loggedDeprecations = [];
  36
  37         /**
  38          * @param array $lbConf Config for LBFactory::__construct()
  39          * @param Config $mainConfig Main config object from MediaWikiServices
  40          * @param ConfiguredReadOnlyMode $readOnlyMode
  41          * @param BagOStuff $srvCace
  42          * @param BagOStuff $mainStash
  43          * @param WANObjectCache $wanCache
  44          * @return array
  45          */
  46         public static function applyDefaultConfig(
  47                 array $lbConf,
  48                 Config $mainConfig,
  49                 ConfiguredReadOnlyMode $readOnlyMode,
  50                 BagOStuff $srvCace,
  51                 BagOStuff $mainStash,
  52                 WANObjectCache $wanCache
  53         ) {
  54                 global $wgCommandLineMode;
  55
  56                 $typesWithSchema = self::getDbTypesWithSchemas();
  57
  58                 $lbConf += [
  59                         'localDomain' => new DatabaseDomain(
  60                                 $mainConfig->get( 'DBname' ),
  61                                 $mainConfig->get( 'DBmwschema' ),
  62                                 $mainConfig->get( 'DBprefix' )
  63                         ),
  64                         'profiler' => function ( $section ) {
  65                                 return Profiler::instance()->scopedProfileIn( $section );
  66                         },
  67                         'trxProfiler' => Profiler::instance()->getTransactionProfiler(),
  68                         'replLogger' => LoggerFactory::getInstance( 'DBReplication' ),
  69                         'queryLogger' => LoggerFactory::getInstance( 'DBQuery' ),
  70                         'connLogger' => LoggerFactory::getInstance( 'DBConnection' ),
  71                         'perfLogger' => LoggerFactory::getInstance( 'DBPerformance' ),
  72                         'errorLogger' => [ MWExceptionHandler::class, 'logException' ],
  73                         'deprecationLogger' => [ static::class, 'logDeprecation' ],
  74                         'cliMode' => $wgCommandLineMode,
  75                         'hostname' => wfHostname(),
  76                         'readOnlyReason' => $readOnlyMode->getReason(),
  77                         'defaultGroup' => $mainConfig->get( 'DBDefaultGroup' ),
  78                 ];
  79
  80                 $serversCheck = [];
  81                 // When making changes here, remember to also specify MediaWiki-specific options
  82                 // for Database classes in the relevant Installer subclass.
  83                 // Such as MysqlInstaller::openConnection and PostgresInstaller::openConnectionWithParams.
  84                 if ( $lbConf['class'] === Wikimedia\Rdbms\LBFactorySimple::class ) {
  85                         if ( isset( $lbConf['servers'] ) ) {
  86                                 // Server array is already explicitly configured
  87                         } elseif ( is_array( $mainConfig->get( 'DBservers' ) ) ) {
  88                                 $lbConf['servers'] = [];
  89                                 foreach ( $mainConfig->get( 'DBservers' ) as $i => $server ) {
  90                                         $lbConf['servers'][$i] = self::initServerInfo( $server, $mainConfig );
  91                                 }
  92                         } else {
  93                                 $server = self::initServerInfo(
  94                                         [
  95                                                 'host' => $mainConfig->get( 'DBserver' ),
  96                                                 'user' => $mainConfig->get( 'DBuser' ),
  97                                                 'password' => $mainConfig->get( 'DBpassword' ),
  98                                                 'dbname' => $mainConfig->get( 'DBname' ),
  99                                                 'type' => $mainConfig->get( 'DBtype' ),
 100                                                 'load' => 1
 101                                         ],
 102                                         $mainConfig
 103                                 );
 104
 105                                 $server['flags'] |= $mainConfig->get( 'DBssl' ) ? DBO_SSL : 0;
 106                                 $server['flags'] |= $mainConfig->get( 'DBcompress' ) ? DBO_COMPRESS : 0;
 107
 108                                 $lbConf['servers'] = [ $server ];
 109                         }
 110                         if ( !isset( $lbConf['externalClusters'] ) ) {
 111                                 $lbConf['externalClusters'] = $mainConfig->get( 'ExternalServers' );
 112                         }
 113
 114                         $serversCheck = $lbConf['servers'];
 115                 } elseif ( $lbConf['class'] === Wikimedia\Rdbms\LBFactoryMulti::class ) {
 116                         if ( isset( $lbConf['serverTemplate'] ) ) {
 117                                 if ( in_array( $lbConf['serverTemplate']['type'], $typesWithSchema, true ) ) {
 118                                         $lbConf['serverTemplate']['schema'] = $mainConfig->get( 'DBmwschema' );
 119                                 }
 120                                 $lbConf['serverTemplate']['sqlMode'] = $mainConfig->get( 'SQLMode' );
 121                         }
 122                         $serversCheck = [ $lbConf['serverTemplate'] ] ?? [];
 123                 }
 124
 125                 self::assertValidServerConfigs( $serversCheck, $mainConfig );
 126
 127                 $lbConf = self::injectObjectCaches( $lbConf, $srvCace, $mainStash, $wanCache );
 128
 129                 return $lbConf;
 130         }
 131
 132         /**
 133          * @return array
 134          */
 135         private static function getDbTypesWithSchemas() {
 136                 return [ 'postgres', 'msssql' ];
 137         }
 138
 139         /**
 140          * @param array $server
 141          * @param Config $mainConfig
 142          * @return array
 143          */
 144         private static function initServerInfo( array $server, Config $mainConfig ) {
 145                 if ( $server['type'] === 'sqlite' ) {
 146                         $httpMethod = $_SERVER['REQUEST_METHOD'] ?? null;
 147                         // T93097: hint for how file-based databases (e.g. sqlite) should go about locking.
 148                         // See https://www.sqlite.org/lang_transaction.html
 149                         // See https://www.sqlite.org/lockingv3.html#shared_lock
 150                         $isHttpRead = in_array( $httpMethod, [ 'GET', 'HEAD', 'OPTIONS', 'TRACE' ] );
 151                         $server += [
 152                                 'dbDirectory' => $mainConfig->get( 'SQLiteDataDir' ),
 153                                 'trxMode' => $isHttpRead ? 'DEFERRED' : 'IMMEDIATE'
 154                         ];
 155                 } elseif ( $server['type'] === 'postgres' ) {
 156                         $server += [
 157                                 'port' => $mainConfig->get( 'DBport' ),
 158                                 // Work around the reserved word usage in MediaWiki schema
 159                                 'keywordTableMap' => [ 'user' => 'mwuser', 'text' => 'pagecontent' ]
 160                         ];
 161                 } elseif ( $server['type'] === 'mssql' ) {
 162                         $server += [
 163                                 'port' => $mainConfig->get( 'DBport' ),
 164                                 'useWindowsAuth' => $mainConfig->get( 'DBWindowsAuthentication' )
 165                         ];
 166                 }
 167
 168                 if ( in_array( $server['type'], self::getDbTypesWithSchemas(), true ) ) {
 169                         $server += [ 'schema' => $mainConfig->get( 'DBmwschema' ) ];
 170                 }
 171
 172                 $flags = DBO_DEFAULT;
 173                 $flags |= $mainConfig->get( 'DebugDumpSql' ) ? DBO_DEBUG : 0;
 174
 175                 $server += [
 176                         'tablePrefix' => $mainConfig->get( 'DBprefix' ),
 177                         'flags' => $flags,
 178                         'sqlMode' => $mainConfig->get( 'SQLMode' ),
 179                 ];
 180
 181                 return $server;
 182         }
 183
 184         /**
 185          * @param array $lbConf
 186          * @param BagOStuff $sCache
 187          * @param BagOStuff $mStash
 188          * @param WANObjectCache $wCache
 189          * @return array
 190          */
 191         private static function injectObjectCaches(
 192                 array $lbConf, BagOStuff $sCache, BagOStuff $mStash, WANObjectCache $wCache
 193         ) {
 194                 // Use APC/memcached style caching, but avoids loops with CACHE_DB (T141804)
 195                 if ( $sCache->getQoS( $sCache::ATTR_EMULATION ) > $sCache::QOS_EMULATION_SQL ) {
 196                         $lbConf['srvCache'] = $sCache;
 197                 }
 198                 if ( $mStash->getQoS( $mStash::ATTR_EMULATION ) > $mStash::QOS_EMULATION_SQL ) {
 199                         $lbConf['memStash'] = $mStash;
 200                 }
 201                 if ( $wCache->getQoS( $wCache::ATTR_EMULATION ) > $wCache::QOS_EMULATION_SQL ) {
 202                         $lbConf['wanCache'] = $wCache;
 203                 }
 204
 205                 return $lbConf;
 206         }
 207
 208         /**
 209          * @param array $servers
 210          * @param Config $mainConfig
 211          */
 212         private static function assertValidServerConfigs( array $servers, Config $mainConfig ) {
 213                 $ldDB = $mainConfig->get( 'DBname' ); // local domain DB
 214                 $ldTP = $mainConfig->get( 'DBprefix' ); // local domain prefix
 215
 216                 foreach ( $servers as $server ) {
 217                         $type = $server['type'] ?? null;
 218                         $srvDB = $server['dbname'] ?? null; // server DB
 219                         $srvTP = $server['tablePrefix'] ?? ''; // server table prefix
 220
 221                         if ( $type === 'mysql' ) {
 222                                 // A DB name is not needed to connect to mysql; 'dbname' is useless.
 223                                 // This field only defines the DB to use for unspecified DB domains.
 224                                 if ( $srvDB !== null && $srvDB !== $ldDB ) {
 225                                         self::reportMismatchedDBs( $srvDB, $ldDB );
 226                                 }
 227                         } elseif ( $type === 'postgres' ) {
 228                                 if ( $srvTP !== '' ) {
 229                                         self::reportIfPrefixSet( $srvTP, $type );
 230                                 }
 231                         }
 232
 233                         if ( $srvTP !== '' && $srvTP !== $ldTP ) {
 234                                 self::reportMismatchedPrefixes( $srvTP, $ldTP );
 235                         }
 236                 }
 237         }
 238
 239         /**
 240          * @param string $prefix Table prefix
 241          * @param string $dbType Database type
 242          */
 243         private static function reportIfPrefixSet( $prefix, $dbType ) {
 244                 $e = new UnexpectedValueException(
 245                         "\$wgDBprefix is set to '$prefix' but the database type is '$dbType'. " .
 246                         "MediaWiki does not support using a table prefix with this RDBMS type."
 247                 );
 248                 MWExceptionRenderer::output( $e, MWExceptionRenderer::AS_PRETTY );
 249                 exit;
 250         }
 251
 252         /**
 253          * @param string $srvDB Server config database
 254          * @param string $ldDB Local DB domain database
 255          */
 256         private static function reportMismatchedDBs( $srvDB, $ldDB ) {
 257                 $e = new UnexpectedValueException(
 258                         "\$wgDBservers has dbname='$srvDB' but \$wgDBname='$ldDB'. " .
 259                         "Set \$wgDBname to the database used by this wiki project. " .
 260                         "There is rarely a need to set 'dbname' in \$wgDBservers. " .
 261                         "Cross-wiki database access, use of WikiMap::getCurrentWikiDbDomain(), " .
 262                         "use of Database::getDomainId(), and other features are not reliable when " .
 263                         "\$wgDBservers does not match the local wiki database/prefix."
 264                 );
 265                 MWExceptionRenderer::output( $e, MWExceptionRenderer::AS_PRETTY );
 266                 exit;
 267         }
 268
 269         /**
 270          * @param string $srvTP Server config table prefix
 271          * @param string $ldTP Local DB domain database
 272          */
 273         private static function reportMismatchedPrefixes( $srvTP, $ldTP ) {
 274                 $e = new UnexpectedValueException(
 275                         "\$wgDBservers has tablePrefix='$srvTP' but \$wgDBprefix='$ldTP'. " .
 276                         "Set \$wgDBprefix to the table prefix used by this wiki project. " .
 277                         "There is rarely a need to set 'tablePrefix' in \$wgDBservers. " .
 278                         "Cross-wiki database access, use of WikiMap::getCurrentWikiDbDomain(), " .
 279                         "use of Database::getDomainId(), and other features are not reliable when " .
 280                         "\$wgDBservers does not match the local wiki database/prefix."
 281                 );
 282                 MWExceptionRenderer::output( $e, MWExceptionRenderer::AS_PRETTY );
 283                 exit;
 284         }
 285
 286         /**
 287          * Returns the LBFactory class to use and the load balancer configuration.
 288          *
 289          * @todo instead of this, use a ServiceContainer for managing the different implementations.
 290          *
 291          * @param array $config (e.g. $wgLBFactoryConf)
 292          * @return string Class name
 293          */
 294         public static function getLBFactoryClass( array $config ) {
 295                 // For configuration backward compatibility after removing
 296                 // underscores from class names in MediaWiki 1.23.
 297                 $bcClasses = [
 298                         'LBFactory_Simple' => 'LBFactorySimple',
 299                         'LBFactory_Single' => 'LBFactorySingle',
 300                         'LBFactory_Multi' => 'LBFactoryMulti'
 301                 ];
 302
 303                 $class = $config['class'];
 304
 305                 if ( isset( $bcClasses[$class] ) ) {
 306                         $class = $bcClasses[$class];
 307                         wfDeprecated(
 308                                 '$wgLBFactoryConf must be updated. See RELEASE-NOTES for details',
 309                                 '1.23'
 310                         );
 311                 }
 312
 313                 // For configuration backward compatibility after moving classes to namespaces (1.29)
 314                 $compat = [
 315                         'LBFactorySingle' => Wikimedia\Rdbms\LBFactorySingle::class,
 316                         'LBFactorySimple' => Wikimedia\Rdbms\LBFactorySimple::class,
 317                         'LBFactoryMulti' => Wikimedia\Rdbms\LBFactoryMulti::class
 318                 ];
 319
 320                 if ( isset( $compat[$class] ) ) {
 321                         $class = $compat[$class];
 322                 }
 323
 324                 return $class;
 325         }
 326
 327         public static function setSchemaAliases( LBFactory $lbFactory, Config $config ) {
 328                 if ( $config->get( 'DBtype' ) === 'mysql' ) {
 329                         /**
 330                          * When SQLite indexes were introduced in r45764, it was noted that
 331                          * SQLite requires index names to be unique within the whole database,
 332                          * not just within a schema. As discussed in CR r45819, to avoid the
 333                          * need for a schema change on existing installations, the indexes
 334                          * were implicitly mapped from the new names to the old names.
 335                          *
 336                          * This mapping can be removed if DB patches are introduced to alter
 337                          * the relevant tables in existing installations. Note that because
 338                          * this index mapping applies to table creation, even new installations
 339                          * of MySQL have the old names (except for installations created during
 340                          * a period where this mapping was inappropriately removed, see
 341                          * T154872).
 342                          */
 343                         $lbFactory->setIndexAliases( [
 344                                 'ar_usertext_timestamp' => 'usertext_timestamp',
 345                                 'un_user_id' => 'user_id',
 346                                 'un_user_ip' => 'user_ip',
 347                         ] );
 348                 }
 349         }
 350
 351         /**
 352          * Log a database deprecation warning
 353          * @param string $msg Deprecation message
 354          */
 355         public static function logDeprecation( $msg ) {
 356                 global $wgDevelopmentWarnings;
 357
 358                 if ( isset( self::$loggedDeprecations[$msg] ) ) {
 359                         return;
 360                 }
 361                 self::$loggedDeprecations[$msg] = true;
 362
 363                 if ( $wgDevelopmentWarnings ) {
 364                         trigger_error( $msg, E_USER_DEPRECATED );
 365                 }
 366                 wfDebugLog( 'deprecated', $msg, 'private' );
 367         }
 368 }