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