MaintenanceRunner.php

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<?php
 
namespace MediaWiki\Maintenance;
 
use Exception;
use LogicException;
use MediaWiki;
use MediaWiki\Config\Config;
use MediaWiki\Deferred\DeferredUpdates;
use MediaWiki\Language\LCStoreNull;
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Profiler\Profiler;
use MediaWiki\Settings\SettingsBuilder;
use ReflectionClass;
use Throwable;
 
class MaintenanceRunner {
 
    private $script = null;
 
    private $scriptClass = null;
 
    private $scriptArgv = null;
 
    private $scriptObject = null;
 
    private $parameters;
 
    private $runFromWrapper = false;
    private bool $withoutLocalSettings = false;
    private ?Config $config = null;
 
    public function __construct() {
        $this->parameters = new MaintenanceParameters();
        $this->addDefaultParams();
    }
 
    private function getConfig(): Config {
        if ( $this->config === null ) {
            $this->config = $this->getServiceContainer()->getMainConfig();
        }
 
        return $this->config;
    }
 
    protected function addDefaultParams() {
        // Generic (non-script-dependent) options:
 
        $this->parameters->addOption( 'conf', 'Location of LocalSettings.php, if not default', false, true );
        $this->parameters->addOption( 'wiki', 'For specifying the wiki ID', false, true );
        $this->parameters->addOption( 'globals', 'Output globals at the end of processing for debugging' );
        $this->parameters->addOption(
            'memory-limit',
            'Set a specific memory limit for the script, '
            . '"max" for no limit or "default" to avoid changing it',
            false,
            true
        );
        $this->parameters->addOption( 'server', "The protocol and server name to use in URLs, e.g. " .
            "https://en.wikipedia.org. This is sometimes necessary because " .
            "server name detection may fail in command line scripts.", false, true );
        $this->parameters->addOption( 'profiler', 'Profiler output format (usually "text")', false, true );
 
        // Save generic options to display them separately in help
        $generic = $this->parameters->getOptionNames();
        $this->parameters->assignGroup( Maintenance::GENERIC_MAINTENANCE_PARAMETERS, $generic );
    }
 
    private function showHelpAndExit( $code = 0 ): never {
        foreach ( $this->parameters->getErrors() as $error ) {
            $this->error( "$error\n" );
            $code = 1;
        }
 
        $this->parameters->setDescription( 'Runner for maintenance scripts' );
 
        $help = $this->parameters->getHelp();
        echo $help;
        exit( $code );
    }
 
    public function initFromWrapper( array $argv ) {
        $script = null;
 
        $this->parameters->setName( $argv[0] );
        $this->parameters->setAllowUnregisteredOptions( true );
        $this->parameters->addArg(
            'script',
            'The name of the maintenance script to run. ' .
                'Can be given as a class name or file path. The `.php` suffix is optional. ' .
                'Paths starting with `./` or `../` are interpreted to be relative to the current working directory. ' .
                'Other relative paths are interpreted relative to the maintenance script directory. ' .
                'Dots (.) are supported as namespace separators in class names. ' .
                'An extension name may be provided as a prefix, followed by a colon, e.g. "MyExtension:...", ' .
                'to indicate that the path or class name should be interpreted relative to the extension.'
        );
 
        $this->runFromWrapper = true;
        $this->parameters->loadWithArgv( $argv, 1 );
 
        // script params
        $argv = array_slice( $argv, 2 );
 
        if ( $this->parameters->validate() ) {
            $script = $this->parameters->getArg( 0 );
 
            // Special handling for the 'help' command
            if ( $script === 'help' ) {
                if ( $this->parameters->hasArg( 1 ) ) {
                    $script = $this->parameters->getArg( 1 );
 
                    // turn <help> <command> into <command> --help
                    $this->parameters->loadWithArgv( [ $script ] );
                    $argv = [ '--help' ];
                } else {
                    // same as no command
                    $script = null;
                }
            }
        }
 
        if ( $script ) {
            // Strip another argument from $argv!
            $this->initInternal( $script, $argv );
        } else {
            $this->showHelpAndExit();
        }
    }
 
    public function initForClass( string $scriptClass, $argv ) {
        $this->runFromWrapper = false;
        $this->script = $scriptClass;
        $this->scriptClass = $scriptClass;
        $this->parameters->setName( $argv[0] );
        $this->parameters->loadWithArgv( $argv );
        $this->initInternal( $scriptClass, array_slice( $argv, 1 ) );
    }
 
    private function initInternal( string $script, array $scriptArgv ) {
        $this->script = $script;
        $this->scriptArgv = $scriptArgv;
 
        // Send PHP warnings and errors to stderr instead of stdout.
        // This aids in diagnosing problems, while keeping messages
        // out of redirected output.
        if ( ini_get( 'display_errors' ) ) {
            ini_set( 'display_errors', 'stderr' );
        }
 
        // make sure we clean up after ourselves.
        register_shutdown_function( $this->cleanup( ... ) );
 
        // Turn off output buffering if it's on
        while ( ob_get_level() > 0 ) {
            ob_end_flush();
        }
    }
 
    private static function isAbsolutePath( string $path ): bool {
        if ( str_starts_with( $path, '/' ) ) {
            return true;
        }
 
        if ( wfIsWindows() ) {
            if ( str_starts_with( $path, '\\' ) ) {
                return true;
            }
            if ( preg_match( '!^[a-zA-Z]:[/\\\\]!', $path ) ) {
                return true;
            }
        }
 
        return false;
    }
 
    protected function getExtensionInfo( string $extName ): ?array {
        // NOTE: Don't go by the extension registry, since some extensions
        //       register under a name different from what is used in wfLoadExtension.
        //       E.g. AbuseFilter is registered as "Abuse Filter" with a space.
 
        $config = SettingsBuilder::getInstance()->getConfig();
        $extDir = $config->get( MainConfigNames::ExtensionDirectory );
        $skinDir = $config->get( MainConfigNames::StyleDirectory );
 
        $extension = [];
        if ( file_exists( "$extDir/$extName/extension.json" ) ) {
            $extension['path'] = "$extDir/$extName/extension.json";
            $extension['namespace'] = "MediaWiki\\Extension\\$extName";
        } elseif ( file_exists( "$skinDir/$extName/skin.json" ) ) {
            $extension['path'] = "$skinDir/$extName/skin.json";
            $extension['namespace'] = "MediaWiki\\Skins\\$extName";
        } else {
            return null;
        }
 
        return $extension;
    }
 
    private function loadScriptFile( string $scriptFile ): ?string {
        $maintClass = null;
 
        // It's a file, include it
        // If it returns something, it should be the name of the maintenance class.
        $scriptClass = include $scriptFile;
 
        // Traditional script files set the $maintClass variable
        // at the end of the file.
        // @phan-suppress-next-line PhanImpossibleCondition Phan doesn't understand includes.
        if ( $maintClass ) {
            $scriptClass = $maintClass;
        }
 
        return is_string( $scriptClass ) ? $scriptClass : null;
    }
 
    private function splitScript( string $script ): array {
        // Support "$ext:$script" format for extensions
        if ( preg_match( '!^(\w+):(.*)$!', $script, $m ) ) {
            return [ $m[1], $m[2] ];
        }
 
        return [ null, $script ];
    }
 
    protected function getMwInstallPath(): string {
        return MW_INSTALL_PATH;
    }
 
    private function expandScriptFile( string $scriptName, ?array $extension ): string {
        // Append ".php" if not present
        $scriptFile = $scriptName;
        if ( !str_ends_with( $scriptFile, '.php' ) ) {
            $scriptFile .= '.php';
        }
 
        // If the path is not explicitly relative (starting with "./" or "../") and not absolute,
        // then look in the maintenance dir.
        if ( !preg_match( '!^\.\.?[/\\\\]!', $scriptFile ) && !self::isAbsolutePath( $scriptFile ) ) {
            if ( $extension !== null ) {
                // Look in the extension's maintenance dir
                $scriptFile = dirname( $extension['path'] ) . "/maintenance/{$scriptFile}";
            } else {
                // It's a core script.
                $scriptFile = $this->getMwInstallPath() . "/maintenance/{$scriptFile}";
            }
        }
 
        return $scriptFile;
    }
 
    private function expandScriptClass( string $scriptName, ?array $extension ): string {
        $scriptClass = $scriptName;
 
        // Support "$ext:$script" format
        if ( $extension ) {
            $scriptClass = "{$extension['namespace']}\\Maintenance\\$scriptClass";
        }
 
        // Accept dot (.) as namespace separators as well.
        // Backslashes are just annoying on the command line.
        $scriptClass = strtr( $scriptClass, '.', '\\' );
 
        return $scriptClass;
    }
 
    protected function preloadScriptFile( string $script ): void {
        if ( $this->scriptClass !== null && class_exists( $this->scriptClass ) ) {
            // We know the script class, and file-level code was executed because class_exists triggers auto-loading.
            return;
        }
 
        [ $extName, $scriptName ] = $this->splitScript( $script );
 
        if ( $extName !== null ) {
            // Preloading is not supported. findScriptClass() will try to find the script later.
            return;
        }
 
        $scriptClass = $this->expandScriptClass( $scriptName, null );
        $scriptFile = $this->expandScriptFile( $scriptName, null );
 
        if ( !class_exists( $scriptClass ) && file_exists( $scriptFile ) ) {
            $scriptFileClass = $this->loadScriptFile( $scriptFile );
            if ( $scriptFileClass ) {
                $scriptClass = $scriptFileClass;
            }
        }
 
        // NOTE: class_exists will trigger auto-loading, so file-level code in the script file will run.
        if ( class_exists( $scriptClass ) ) {
            // Set the script class name we found, so we don't try to load the file again!
            $this->scriptClass = $scriptClass;
        }
 
        // Preloading failed. Let findScriptClass() try to find the script later.
    }
 
    protected function getScriptClass(): string {
        if ( $this->scriptClass === null ) {
            if ( $this->runFromWrapper ) {
                $this->scriptClass = $this->findScriptClass( $this->script );
            } else {
                $this->scriptClass = $this->script;
            }
        }
 
        if ( !class_exists( $this->scriptClass ) ) {
            $this->fatalError( "Script class {$this->scriptClass} not found.\n" );
        }
 
        return $this->scriptClass;
    }
 
    protected function findScriptClass( string $script ): string {
        [ $extName, $scriptName ] = $this->splitScript( $script );
 
        if ( $extName !== null ) {
            $extension = $this->getExtensionInfo( $extName );
 
            if ( !$extension ) {
                $this->fatalError( "Extension '{$extName}' not found.\n" );
            }
        } else {
            $extension = null;
        }
 
        $scriptClass = $this->expandScriptClass( $scriptName, $extension );
        $scriptFile = $this->expandScriptFile( $scriptName, $extension );
 
        if ( !class_exists( $scriptClass ) && file_exists( $scriptFile ) ) {
            // The guessed class is not registered with the autoloader.
            // Let's see if the script defines the class to use in the old way.
            $scriptFileClass = $this->loadScriptFile( $scriptFile );
            if ( !$scriptFileClass && class_exists( $scriptClass ) ) {
                // It doesn't, but instead it contains the guessed class, so it should have been autoloaded.
                $this->error( "WARNING: The script class '{$scriptClass}' is not registered with the autoloader.\n" );
            } elseif ( !$scriptFileClass ) {
                // It doesn't.
                $this->error( "ERROR: The script file '{$scriptFile}' cannot be executed using MaintenanceRunner.\n" );
                $this->error( "It does not set \$maintClass and does not return a class name.\n" );
                $this->fatalError( "Try running it directly as a php script: php $scriptFile\n" );
            } else {
                // It does! We'll check whether the class really exists below.
                $scriptClass = $scriptFileClass;
            }
        }
 
        if ( !class_exists( $scriptClass ) ) {
            $this->fatalError( "Script '{$script}' not found (tried path '$scriptFile' and class '$scriptClass').\n" );
        }
 
        return $scriptClass;
    }
 
    public function setup( SettingsBuilder $settings ) {
        // NOTE: this has to happen after the autoloader has been initialized.
        $scriptClass = $this->getScriptClass();
 
        $cls = new ReflectionClass( $scriptClass );
        if ( !$cls->isSubclassOf( Maintenance::class ) ) {
            $this->fatalError( "Class {$this->script} is not a subclass of Maintenance.\n" );
        }
 
        // Initialize the actual Maintenance object
        try {
            $this->scriptObject = new $scriptClass;
            $this->scriptObject->setName( $this->getName() );
        } catch ( Throwable $ex ) {
            $this->fatalError(
                "Failed to initialize Maintenance object.\n" .
                "(Did you forget to call parent::__construct() in your maintenance script?)\n" .
                "$ex\n"
            );
        }
 
        if ( !$this->scriptObject instanceof Maintenance ) {
            // This should never happen, we already checked if the class is a subclass of Maintenance!
            throw new LogicException( 'Incompatible script object' );
        }
 
        // Inject runner stuff into the script's parameter definitions.
        // This is mainly used when printing help.
        $scriptParameters = $this->scriptObject->getParameters();
 
        if ( $this->runFromWrapper ) {
            $scriptParameters->setUsagePrefix( 'php ' . $this->parameters->getName() );
        }
 
        $scriptParameters->mergeOptions( $this->parameters );
        $this->parameters = $scriptParameters;
 
        // Ingest argv
        $this->scriptObject->loadWithArgv( $this->scriptArgv );
 
        // Basic checks and such
        $this->scriptObject->setup();
 
        $this->adjustMemoryLimit();
 
        // Override any config settings
        $this->overrideConfig( $settings );
    }
 
    public function getName(): string {
        // Once one of the init methods was called, getArg( 0 ) should always
        // return something.
        return $this->parameters->getArg( 0 ) ?? 'UNKNOWN';
    }
 
    private function adjustMemoryLimit() {
        if ( $this->parameters->hasOption( 'memory-limit' ) ) {
            $limit = $this->parameters->getOption( 'memory-limit', 'max' );
            $limit = trim( $limit, "\" '" ); // trim quotes in case someone misunderstood
        } else {
            $limit = $this->scriptObject->memoryLimit() ?: 'max';
        }
        if ( $limit == 'max' ) {
            $limit = -1; // no memory limit
        }
        if ( $limit != 'default' ) {
            // NOTE: This should not override $wgMemoryLimit and ride the wfMemoryLimit() call in Setup.php.
            //
            // We are still in MW_FINAL_SETUP_CALLBACK in Setup.php, before that calls wfMemoryLimit(),
            // and we can still set $wgMemoryLimit here or in MaintenanceRunner::overrideConfig.
            // But, $wgMemoryLimit is a way to *raise* the memory limit, mainly for web requests
            // where the system default is often less than what we need.
            //
            // Maintenance::memoryLimit, however, is to *lower* the memory limit (often -1 for PHP-CLI).
            // If we override $wgMemoryLimit and let Setup.php call wfMemoryLimit, it would do nothing
            // when memory_limit=-1 and run maintenance scripts with unlimited memory.
            ini_set( 'memory_limit', $limit );
        }
    }
 
    public function defineSettings() {
        global $IP;
 
        if ( $this->parameters->hasOption( 'conf' ) ) {
            // Define the constant instead of directly setting $settingsFile
            // to ensure consistency. wfDetectLocalSettingsFile() will return
            // MW_CONFIG_FILE if it is defined.
            define( 'MW_CONFIG_FILE', $this->parameters->getOption( 'conf' ) );
 
            if ( !is_readable( MW_CONFIG_FILE ) ) {
                $this->fatalError( "\nConfig file " . MW_CONFIG_FILE . " was not found or is not readable.\n\n" );
            }
        }
        $settingsFile = wfDetectLocalSettingsFile( $IP );
 
        if ( $this->parameters->hasOption( 'wiki' ) ) {
            $wikiName = $this->parameters->getOption( 'wiki' );
            $bits = explode( '-', $wikiName, 2 );
            define( 'MW_DB', $bits[0] );
            define( 'MW_PREFIX', $bits[1] ?? '' );
            define( 'MW_WIKI_NAME', $wikiName );
        } elseif ( $this->parameters->hasOption( 'server' ) ) {
            // Provide the option for site admins to detect and configure
            // multiple wikis based on server names. This offers --server
            // as alternative to --wiki.
            // See https://www.mediawiki.org/wiki/Manual:Wiki_family
            $_SERVER['SERVER_NAME'] = $this->parameters->getOption( 'server' );
        }
 
        // Try to load the script file before running Setup.php if possible.
        // This allows the script file to define constants that change the behavior
        // of Setup.php.
        // Note that this will only work reliably for core scripts.
        if ( $this->runFromWrapper ) {
            $this->preloadScriptFile( $this->script );
        }
 
        if ( !is_readable( $settingsFile ) ) {
            // NOTE: Some maintenance scripts can (and need to) run without LocalSettings.
            //       But we only know that once we have instantiated the Maintenance object.
            //       So go into no-settings mode for now, and fail later of the script doesn't support it.
            if ( !defined( 'MW_CONFIG_CALLBACK' ) ) {
                define( 'MW_CONFIG_CALLBACK', self::emulateConfig( ... ) );
            }
            $this->withoutLocalSettings = true;
        }
    }
 
    private static function emulateConfig( SettingsBuilder $settings ) {
        // NOTE: The config schema is already loaded at this point, so default values are known.
 
        $settings->overrideConfigValues( [
            // Server must be set, but we don't care to what
            MainConfigNames::Server => 'https://unknown.invalid',
            // If InvalidateCacheOnLocalSettingsChange is enabled, filemtime( MW_CONFIG_FILE ),
            // which will produce a warning if there is no settings file.
            MainConfigNames::InvalidateCacheOnLocalSettingsChange => false,
        ] );
    }
 
    private function overrideConfig( SettingsBuilder $settingsBuilder ) {
        $config = $settingsBuilder->getConfig();
 
        if ( $this->scriptObject->getDbType() === Maintenance::DB_NONE ) {
            $cacheConf = $config->get( MainConfigNames::LocalisationCacheConf );
            if ( $cacheConf['storeClass'] === false
                && ( $cacheConf['store'] == 'db'
                    || ( $cacheConf['store'] == 'detect'
                        && !$config->get( MainConfigNames::CacheDirectory ) ) )
            ) {
                $cacheConf['storeClass'] = LCStoreNull::class;
                $settingsBuilder->putConfigValue( MainConfigNames::LocalisationCacheConf, $cacheConf );
            }
        }
 
        $output = $this->parameters->getOption( 'profiler' );
        if ( $output ) {
            // Per-script profiling; useful for debugging
            $profilerConf = $config->get( MainConfigNames::Profiler );
            if ( isset( $profilerConf['class'] ) ) {
                $profilerConf = [
                    'sampling' => 1,
                    'output' => [ $output ],
                    'cliEnable' => true,
                ] + $profilerConf;
                // Override $wgProfiler. This is passed to Profiler::init() by Setup.php.
                $settingsBuilder->putConfigValue( MainConfigNames::Profiler, $profilerConf );
            }
        }
 
        $this->scriptObject->finalSetup( $settingsBuilder );
    }
 
    private function getServiceContainer(): MediaWikiServices {
        return MediaWikiServices::getInstance();
    }
 
    public function run(): bool {
        $config = $this->getConfig();
 
        // Apply warning thresholds and output mode to Profiler.
        // This MUST happen after Setup.php calls MaintenanceRunner::setup,
        // $wgSettings->apply(), and Profiler::init(). Otherwise, calling
        // Profiler::instance() would create a ProfilerStub even when $wgProfiler
        // and --profiler are set.
        $limits = $config->get( MainConfigNames::TrxProfilerLimits );
        $trxProfiler = Profiler::instance()->getTransactionProfiler();
        $trxProfiler->setLogger( LoggerFactory::getInstance( 'rdbms' ) );
        $trxProfiler->setExpectations( $limits['Maintenance'], __METHOD__ );
        Profiler::instance()->setAllowOutput();
 
        // Initialize main config instance
        $this->scriptObject->setConfig( $config );
 
        // Double check required extensions are installed
        $this->scriptObject->checkRequiredExtensions();
 
        if ( $this->withoutLocalSettings && !$this->scriptObject->canExecuteWithoutLocalSettings() ) {
            $this->fatalError(
                "\nThe LocalSettings.php file was not found or is not readable.\n" .
                "Use --conf to specify an alternative config file.\n\n"
            );
        }
 
        if ( $this->scriptObject->getDbType() == Maintenance::DB_NONE || $this->withoutLocalSettings ) {
            // Be strict with maintenance tasks that claim to not need a database by
            // disabling the storage backend.
            MediaWikiServices::resetGlobalInstance( $config );
            MediaWikiServices::getInstance()->disableStorage();
        }
 
        $this->scriptObject->validateParamsAndArgs();
 
        // Do the work
        try {
            $success = $this->scriptObject->execute() !== false;
 
            // Potentially debug globals
            if ( $this->parameters->hasOption( 'globals' ) ) {
                print_r( $GLOBALS );
            }
 
            $this->shutdown();
 
            return $success;
        } catch ( Exception $ex ) {
            $exReportMessage = '';
            while ( $ex ) {
                $cls = get_class( $ex );
                $exReportMessage .= "$cls from line {$ex->getLine()} of {$ex->getFile()}: {$ex->getMessage()}\n";
                $exReportMessage .= $ex->getTraceAsString() . "\n";
                $ex = $ex->getPrevious();
            }
            $this->error( $exReportMessage );
 
            // Exit now because process is in an unsafe state.
            // Also to avoid DBTransactionError (T305730).
            // Do not commit database writes, do not run deferreds, do not pass Go.
            exit( 1 );
        }
    }
 
    protected function fatalError( $msg, $exitCode = 1 ): never {
        $this->error( $msg );
        exit( $exitCode );
    }
 
    protected function error( string $msg ) {
        // Print to stderr if possible, don't mix it in with stdout output.
        if ( defined( 'STDERR' ) ) {
            fwrite( STDERR, $msg );
        } else {
            echo $msg;
        }
    }
 
    public static function shouldExecute() {
        if ( !function_exists( 'debug_backtrace' ) ) {
            // If someone has a better idea...
            return MW_ENTRY_POINT === 'cli';
        }
 
        $bt = debug_backtrace();
        $count = count( $bt );
        if ( $bt[0]['class'] !== self::class || $bt[0]['function'] !== 'shouldExecute' ) {
            return false; // last call should be to this function
        }
        $includeFuncs = [ 'require_once', 'require', 'include', 'include_once' ];
        for ( $i = 1; $i < $count; $i++ ) {
            if ( !in_array( $bt[$i]['function'], $includeFuncs ) ) {
                return false; // previous calls should all be "requires"
            }
        }
 
        return true;
    }
 
    protected function cleanup() {
        if ( $this->scriptObject ) {
            $this->scriptObject->cleanupChanneled();
        }
    }
 
    private function shutdown() {
        $lbFactory = null;
        if (
            $this->scriptObject->getDbType() !== Maintenance::DB_NONE &&
            // Service might be disabled, e.g. when running install.php
            !$this->getServiceContainer()->isServiceDisabled( 'DBLoadBalancerFactory' )
        ) {
            $lbFactory = $this->getServiceContainer()->getDBLoadBalancerFactory();
            if ( $lbFactory->isReadyForRoundOperations() ) {
                $lbFactory->commitPrimaryChanges( get_class( $this ) );
            }
 
            DeferredUpdates::doUpdates();
        }
 
        // Handle profiler outputs
        // NOTE: MaintenanceRunner ensures Profiler::setAllowOutput() during setup
        $profiler = Profiler::instance();
        $profiler->logData();
        $profiler->logDataPageOutputOnly();
 
        MediaWiki::emitBufferedStats(
            $this->getServiceContainer()->getStatsFactory()
        );
 
        if ( $lbFactory ) {
            if ( $lbFactory->isReadyForRoundOperations() ) {
                $lbFactory->shutdown( $lbFactory::SHUTDOWN_NO_CHRONPROT );
            }
        }
    }
 
}