diff options
Diffstat (limited to 'includes/language/LCStoreDB.php')
| -rw-r--r-- | includes/language/LCStoreDB.php | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/includes/language/LCStoreDB.php b/includes/language/LCStoreDB.php new file mode 100644 index 000000000000..d6a9866bb711 --- /dev/null +++ b/includes/language/LCStoreDB.php @@ -0,0 +1,147 @@ +<?php +/** + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + */ + +use Wikimedia\Rdbms\Database; +use Wikimedia\Rdbms\DBQueryError; +use Wikimedia\Rdbms\IDatabase; +use Wikimedia\ScopedCallback; + +/** + * LCStore implementation which uses the standard DB functions to store data. + * This will work on any MediaWiki installation. + */ +class LCStoreDB implements LCStore { + /** @var string|null Language code */ + private $code; + /** @var array Server configuration map */ + private $server; + + /** @var array Rows buffered for insertion */ + private $batch = []; + + /** @var IDatabase|null */ + private $dbw; + /** @var bool Whether a batch of writes were recently written */ + private $writesDone = false; + /** @var bool Whether the DB is read-only or otherwise unavailable for writes */ + private $readOnly = false; + + public function __construct( $params ) { + $this->server = $params['server'] ?? []; + } + + public function get( $code, $key ) { + if ( $this->server || $this->writesDone ) { + // If a server configuration map is specified, always used that connection + // for reads and writes. Otherwise, if writes occurred in finishWrite(), make + // sure those changes are always visible. + $db = $this->getWriteConnection(); + } else { + $db = wfGetDB( DB_REPLICA ); + } + + $value = $db->selectField( + 'l10n_cache', + 'lc_value', + [ 'lc_lang' => $code, 'lc_key' => $key ], + __METHOD__ + ); + + return ( $value !== false ) ? unserialize( $db->decodeBlob( $value ) ) : null; + } + + public function startWrite( $code ) { + if ( $this->readOnly ) { + return; + } elseif ( !$code ) { + throw new MWException( __METHOD__ . ": Invalid language \"$code\"" ); + } + + $dbw = $this->getWriteConnection(); + $this->readOnly = $dbw->isReadOnly(); + + $this->code = $code; + $this->batch = []; + } + + public function finishWrite() { + if ( $this->readOnly ) { + return; + } elseif ( $this->code === null ) { + throw new MWException( __CLASS__ . ': must call startWrite() before finishWrite()' ); + } + + $scope = Profiler::instance()->getTransactionProfiler()->silenceForScope(); + $dbw = $this->getWriteConnection(); + $dbw->startAtomic( __METHOD__ ); + try { + $dbw->delete( 'l10n_cache', [ 'lc_lang' => $this->code ], __METHOD__ ); + foreach ( array_chunk( $this->batch, 500 ) as $rows ) { + $dbw->insert( 'l10n_cache', $rows, __METHOD__ ); + } + $this->writesDone = true; + } catch ( DBQueryError $e ) { + if ( $dbw->wasReadOnlyError() ) { + $this->readOnly = true; // just avoid site down time + } else { + throw $e; + } + } + $dbw->endAtomic( __METHOD__ ); + ScopedCallback::consume( $scope ); + + $this->code = null; + $this->batch = []; + } + + public function set( $key, $value ) { + if ( $this->readOnly ) { + return; + } elseif ( $this->code === null ) { + throw new MWException( __CLASS__ . ': must call startWrite() before set()' ); + } + + $dbw = $this->getWriteConnection(); + + $this->batch[] = [ + 'lc_lang' => $this->code, + 'lc_key' => $key, + 'lc_value' => $dbw->encodeBlob( serialize( $value ) ) + ]; + } + + /** + * @return IDatabase + */ + private function getWriteConnection() { + if ( !$this->dbw ) { + if ( $this->server ) { + $this->dbw = Database::factory( $this->server['type'], $this->server ); + if ( !$this->dbw ) { + throw new MWException( __CLASS__ . ': failed to obtain a DB connection' ); + } + } else { + $this->dbw = wfGetDB( DB_PRIMARY ); + } + } + + return $this->dbw; + } +} |