mysql.php

Go to the documentation of this file.

<?php
use MediaWiki\Maintenance\Maintenance;
use MediaWiki\Shell\Shell;
use Wikimedia\FileBackend\FSFile\TempFSFile;
use Wikimedia\IPUtils;
use Wikimedia\Rdbms\ServerInfo;
 
// @codeCoverageIgnoreStart
require_once __DIR__ . '/Maintenance.php';
// @codeCoverageIgnoreEnd
 
class MysqlMaintenance extends Maintenance {
    public function __construct() {
        parent::__construct();
        $this->addDescription( "Execute the MySQL client binary. " .
            "Non-option arguments will be passed through to mysql." );
        $this->addOption( 'write', 'Connect to the primary database', false, false );
        $this->addOption( 'group', 'Specify query group', false, true );
        $this->addOption( 'host', 'Connect to a known MySQL server', false, true );
        $this->addOption( 'raw-host',
            'Connect directly to a specific MySQL server, even if not known to MediaWiki '
                . 'via wgLBFactoryConf (e.g. parser cache or depooled host). '
                . 'Credentials will be chosen based on --cluster and --wikidb.',
            false,
            true
        );
        $this->addOption( 'list-hosts', 'List the available DB hosts', false, false );
        $this->addOption( 'cluster', 'Use an external cluster by name', false, true );
        $this->addOption( 'wikidb',
            'The database wiki ID to use if not the current one',
            false,
            true
        );
 
        // Fake argument for help message
        $this->addArg( '-- mysql_option ...', 'Options to pass to mysql', false );
    }
 
    public function execute() {
        $dbName = $this->getOption( 'wikidb', false );
        $lbf = $this->getServiceContainer()->getDBLoadBalancerFactory();
 
        // Pick LB
        if ( $this->hasOption( 'cluster' ) ) {
            try {
                $lb = $lbf->getExternalLB( $this->getOption( 'cluster' ) );
            } catch ( InvalidArgumentException ) {
                $this->fatalError( 'Error: invalid cluster' );
            }
        } else {
            $lb = $lbf->getMainLB( $dbName );
        }
 
        // List hosts, or pick host
        if ( $this->hasOption( 'list-hosts' ) ) {
            $serverCount = $lb->getServerCount();
            for ( $index = 0; $index < $serverCount; ++$index ) {
                echo $lb->getServerName( $index ) . "\n";
            }
            return;
        }
        if ( $this->hasOption( 'host' ) ) {
            $host = $this->getOption( 'host' );
            $serverCount = $lb->getServerCount();
            for ( $index = 0; $index < $serverCount; ++$index ) {
                if ( $lb->getServerName( $index ) === $host ) {
                    break;
                }
            }
            if ( $index >= $serverCount ) {
                $this->fatalError( "Error: Host not configured: \"$host\"" );
            }
        } elseif ( $this->hasOption( 'write' ) ) {
            $index = ServerInfo::WRITER_INDEX;
        } else {
            $group = $this->getOption( 'group', false );
            $index = $lb->getReaderIndex( $group );
            if ( $index === false && $group ) {
                // retry without the group; it may not exist
                $index = $lb->getReaderIndex( false );
            }
            if ( $index === false ) {
                $this->fatalError( 'Error: unable to get reader index' );
            }
        }
        if ( $lb->getServerType( $index ) !== 'mysql' ) {
            $this->fatalError( 'Error: this script only works with MySQL/MariaDB' );
        }
 
        $serverInfo = $lb->getServerInfo( $index );
        // Override host. This uses the server info of the host determined
        // by the other options for the purposes of user/password.
        if ( $this->hasOption( 'raw-host' ) ) {
            $host = $this->getOption( 'raw-host' );
            $serverInfo = [ 'host' => $host ] + $serverInfo;
        }
 
        $this->runMysql( $serverInfo, $dbName );
    }
 
    private function runMysql( $info, $dbName ) {
        // Write the password to an option file to avoid disclosing it to other
        // processes running on the system
        $tmpFile = TempFSFile::factory( 'mw-mysql', 'ini' );
        chmod( $tmpFile->getPath(), 0600 );
        file_put_contents( $tmpFile->getPath(), "[client]\npassword={$info['password']}\n" );
 
        // stdin/stdout need to be the actual file descriptors rather than
        // PHP's pipe wrappers so that mysql can use them as an interactive
        // terminal.
        $desc = [
            0 => STDIN,
            1 => STDOUT,
            2 => STDERR,
        ];
 
        // Split host and port as in DatabaseMySQL::mysqlConnect()
        $realServer = $info['host'];
        $hostAndPort = IPUtils::splitHostAndPort( $realServer );
        $socket = false;
        $port = false;
        if ( $hostAndPort ) {
            $realServer = $hostAndPort[0];
            if ( $hostAndPort[1] ) {
                $port = $hostAndPort[1];
            }
        } elseif ( substr_count( $realServer, ':' ) == 1 ) {
            // If we have a colon and something that's not a port number
            // inside the hostname, assume it's the socket location
            [ $realServer, $socket ] = explode( ':', $realServer, 2 );
        }
 
        if ( $dbName === false ) {
            $dbName = $info['dbname'];
        }
 
        $args = [
            'mysql',
            "--defaults-extra-file={$tmpFile->getPath()}",
            "--user={$info['user']}",
            "--database={$dbName}",
        ];
        if ( $socket !== false ) {
            $args[] = "--socket={$socket}";
        } else {
            $args[] = "--host={$realServer}";
        }
        if ( $port !== false ) {
            $args[] = "--port={$port}";
        }
 
        $args = array_merge( $args, $this->getArgs() );
 
        // Ignore SIGINT if possible, otherwise the wrapper terminates when the user presses
        // ctrl-C to kill a query.
        if ( function_exists( 'pcntl_signal' ) ) {
            pcntl_signal( SIGINT, SIG_IGN );
        }
 
        $pipes = [];
        $proc = proc_open( Shell::escape( $args ), $desc, $pipes );
        if ( $proc === false ) {
            $this->fatalError( 'Unable to execute mysql' );
        }
 
        $ret = proc_close( $proc );
        if ( $ret === -1 ) {
            $this->fatalError( 'proc_close() returned -1' );
        } elseif ( $ret ) {
            $this->fatalError( 'Failed.', $ret );
        }
    }
}
 
// @codeCoverageIgnoreStart
$maintClass = MysqlMaintenance::class;
require_once RUN_MAINTENANCE_IF_MAIN;
// @codeCoverageIgnoreEnd