Maintenance.php

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<?php
namespace MediaWiki\Maintenance;
 
use Closure;
use Generator;
use MediaWiki;
use MediaWiki\Config\Config;
use MediaWiki\Config\ConfigException;
use MediaWiki\Deferred\DeferredUpdates;
use MediaWiki\HookContainer\HookContainer;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiEntryPoint;
use MediaWiki\MediaWikiServices;
use MediaWiki\Registration\ExtensionRegistry;
use MediaWiki\Settings\SettingsBuilder;
use MediaWiki\Shell\Shell;
use MediaWiki\User\User;
use MediaWiki\Utils\ExecutableFinder;
use StatusValue;
use Wikimedia\Rdbms\IDatabase;
use Wikimedia\Rdbms\ILBFactory;
use Wikimedia\Rdbms\IMaintainableDatabase;
use Wikimedia\Rdbms\IReadableDatabase;
 
// NOTE: MaintenanceParameters is needed in the constructor, and we may not have
//       autoloading enabled at this point?
require_once __DIR__ . '/MaintenanceParameters.php';
 
abstract class Maintenance {
    public const DB_NONE = 0;
    public const DB_STD = 1;
    public const DB_ADMIN = 2;
 
    // Const for getStdin()
    public const STDIN_ALL = -1;
 
    // Help group names
    public const SCRIPT_DEPENDENT_PARAMETERS = 'Common options';
    public const GENERIC_MAINTENANCE_PARAMETERS = 'Script runner options';
 
    protected $parameters;
 
    protected $mParams = [];
 
    protected $mOptions = [];
 
    protected $mArgs = [];
 
    protected $mSelf;
 
    protected $mQuiet = false;
    protected ?string $mDbUser = null;
    protected ?string $mDbPass = null;
 
    protected $mDescription = '';
 
    protected $mInputLoaded = false;
 
    protected $mBatchSize = null;
 
    private $mDb = null;
 
    private $lastReplicationWait = 0.0;
 
    public $fileHandle;
 
    private $hookContainer;
 
    private $hookRunner;
 
    private $config;
 
    private $requiredExtensions = [];
 
    public $orderedOptions = [];
 
    private ?ILBFactory $lbFactory = null;
 
    private bool $isTesting = false;
 
    public function __construct() {
        $this->parameters = new MaintenanceParameters();
        $this->mOptions =& $this->parameters->getFieldReference( 'mOptions' );
        $this->orderedOptions =& $this->parameters->getFieldReference( 'optionsSequence' );
        $this->mArgs =& $this->parameters->getFieldReference( 'mArgs' );
        $this->addDefaultParams();
    }
 
    public function getParameters() {
        return $this->parameters;
    }
 
    abstract public function execute();
 
    public function canExecuteWithoutLocalSettings(): bool {
        return false;
    }
 
    protected function supportsOption( $name ) {
        return $this->parameters->supportsOption( $name );
    }
 
    protected function addOption( $name, $description, $required = false,
        $withArg = false, $shortName = false, $multiOccurrence = false
    ) {
        $this->parameters->addOption(
            $name,
            $description,
            $required,
            $withArg,
            $shortName,
            $multiOccurrence
        );
    }
 
    protected function hasOption( $name ) {
        return $this->parameters->hasOption( $name );
    }
 
    protected function getOption( $name, $default = null ) {
        return $this->parameters->getOption( $name, $default );
    }
 
    protected function addArg( $arg, $description, $required = true, $multi = false ) {
        $this->parameters->addArg( $arg, $description, $required, $multi );
    }
 
    protected function deleteOption( $name ) {
        $this->parameters->deleteOption( $name );
    }
 
    protected function setAllowUnregisteredOptions( $allow ) {
        $this->parameters->setAllowUnregisteredOptions( $allow );
    }
 
    protected function addDescription( $text ) {
        $this->parameters->setDescription( $text );
    }
 
    protected function hasArg( $argId = 0 ) {
        return $this->parameters->hasArg( $argId );
    }
 
    protected function getArg( $argId = 0, $default = null ) {
        return $this->parameters->getArg( $argId, $default );
    }
 
    protected function getArgs( $offset = 0 ) {
        return $this->parameters->getArgs( $offset );
    }
 
    protected function getArgName( int $argId ): ?string {
        return $this->parameters->getArgName( $argId );
    }
 
    public function setOption( string $name, $value ): void {
        $this->parameters->setOption( $name, $value );
    }
 
    public function setArg( $argId, $value ): void {
        $this->parameters->setArg( $argId, $value );
    }
 
    protected function getBatchSize() {
        return $this->mBatchSize;
    }
 
    protected function setBatchSize( $s = 0 ) {
        $this->mBatchSize = $s;
 
        // If we support $mBatchSize, show the option.
        // Used to be in addDefaultParams, but in order for that to
        // work, subclasses would have to call this function in the constructor
        // before they called parent::__construct which is just weird
        // (and really wasn't done).
        if ( $this->mBatchSize ) {
            $this->addOption( 'batch-size', 'Run this many operations ' .
                'per batch, default: ' . $this->mBatchSize, false, true );
            if ( $this->supportsOption( 'batch-size' ) ) {
                // This seems a little ugly...
                $this->parameters->assignGroup( self::SCRIPT_DEPENDENT_PARAMETERS, [ 'batch-size' ] );
            }
        }
    }
 
    public function getName() {
        return $this->mSelf;
    }
 
    protected function getStdin( $len = null ) {
        if ( $len == self::STDIN_ALL ) {
            return file_get_contents( 'php://stdin' );
        }
        $f = fopen( 'php://stdin', 'rt' );
        if ( !$len ) {
            return $f;
        }
        $input = fgets( $f, $len );
        fclose( $f );
 
        return rtrim( $input );
    }
 
    public function isQuiet() {
        return $this->mQuiet;
    }
 
    protected function output( $out, $channel = null ) {
        // This is sometimes called very early, before Setup.php is included.
        if ( defined( 'MW_SERVICE_BOOTSTRAP_COMPLETE' ) ) {
            // Flush stats periodically in long-running CLI scripts to avoid OOM (T181385)
            $statsFactory = $this->getServiceContainer()->getStatsFactory();
            MediaWiki::emitBufferedStats( $statsFactory );
        }
 
        if ( $this->mQuiet ) {
            return;
        }
        if ( $channel === null ) {
            $this->cleanupChanneled();
            print $out;
        } else {
            $out = preg_replace( '/\n\z/', '', $out );
            $this->outputChanneled( $out, $channel );
        }
    }
 
    protected function error( $err ) {
        if ( $err instanceof StatusValue ) {
            foreach ( [ 'warning' => 'Warning: ', 'error' => 'Error: ' ] as $type => $prefix ) {
                foreach ( $err->getMessages( $type ) as $msg ) {
                    $this->error(
                        $prefix . wfMessage( $msg )
                            ->inLanguage( 'en' )
                            ->useDatabase( false )
                            ->text()
                    );
                }
            }
            return;
        }
        $this->outputChanneled( false );
        if (
            ( PHP_SAPI == 'cli' || PHP_SAPI == 'phpdbg' ) &&
            !defined( 'MW_PHPUNIT_TEST' )
        ) {
            fwrite( STDERR, $err . "\n" );
        } else {
            print $err . "\n";
        }
    }
 
    protected function fatalError( $msg, $exitCode = 1 ) {
        $this->error( $msg );
        // If running PHPUnit tests we don't want to call exit, as it will end the test suite early.
        // Instead, throw an exception that will still cause the relevant test to fail if the ::fatalError
        // call was not expected.
        if ( defined( 'MW_PHPUNIT_TEST' ) && $this->isTesting ) {
            throw new MaintenanceFatalError( $exitCode );
        } else {
            exit( $exitCode );
        }
    }
 
    private $atLineStart = true;
    private $lastChannel = null;
 
    public function cleanupChanneled() {
        if ( !$this->atLineStart ) {
            print "\n";
            $this->atLineStart = true;
        }
    }
 
    public function outputChanneled( $msg, $channel = null ) {
        if ( $msg === false ) {
            $this->cleanupChanneled();
 
            return;
        }
 
        // End the current line if necessary
        if ( !$this->atLineStart && $channel !== $this->lastChannel ) {
            print "\n";
        }
 
        print $msg;
 
        $this->atLineStart = false;
        if ( $channel === null ) {
            // For unchanneled messages, output trailing newline immediately
            print "\n";
            $this->atLineStart = true;
        }
        $this->lastChannel = $channel;
    }
 
    public function getDbType() {
        return self::DB_STD;
    }
 
    protected function addDefaultParams() {
        # Generic (non-script-dependent) options:
 
        $this->addOption( 'help', 'Display this help message', false, false, 'h' );
        $this->addOption( 'quiet', 'Whether to suppress non-error output', false, false, 'q' );
 
        # Save generic options to display them separately in help
        $generic = [ 'help', 'quiet' ];
        $this->parameters->assignGroup( self::GENERIC_MAINTENANCE_PARAMETERS, $generic );
 
        # Script-dependent options:
 
        // If we support a DB, show the options
        if ( $this->getDbType() > 0 ) {
            $this->addOption( 'dbuser', 'The DB user to use for this script', false, true );
            $this->addOption( 'dbpass', 'The password to use for this script', false, true );
            $this->addOption( 'dbgroupdefault', 'The default DB group to use.', false, true );
        }
 
        # Save additional script-dependent options to display
        # them separately in help
        $dependent = array_diff(
            $this->parameters->getOptionNames(),
            $generic
        );
        $this->parameters->assignGroup( self::SCRIPT_DEPENDENT_PARAMETERS, $dependent );
    }
 
    public function getConfig() {
        if ( $this->config === null ) {
            $this->config = $this->getServiceContainer()->getMainConfig();
        }
 
        return $this->config;
    }
 
    protected function getServiceContainer() {
        return MediaWikiServices::getInstance();
    }
 
    public function setConfig( Config $config ) {
        $this->config = $config;
    }
 
    protected function requireExtension( $name ) {
        $this->requiredExtensions[] = $name;
    }
 
    public function checkRequiredExtensions() {
        $registry = ExtensionRegistry::getInstance();
        $missing = [];
        foreach ( $this->requiredExtensions as $name ) {
            if ( !$registry->isLoaded( $name ) ) {
                $missing[] = $name;
            }
        }
 
        if ( $missing ) {
            if ( count( $missing ) === 1 ) {
                $msg = 'The "' . $missing[ 0 ] . '" extension must be installed for this script to run. '
                    . 'Please enable it and then try again.';
            } else {
                $msg = 'The following extensions must be installed for this script to run: "'
                    . implode( '", "', $missing ) . '". Please enable them and then try again.';
            }
            $this->fatalError( $msg );
        }
    }
 
    public function createChild( string $maintClass, ?string $classFile = null ): Maintenance {
        // Make sure the class is loaded first
        if ( !class_exists( $maintClass ) ) {
            if ( $classFile ) {
                require_once $classFile;
            }
            if ( !class_exists( $maintClass ) ) {
                $this->fatalError( "Cannot spawn child: $maintClass" );
            }
        }
 
        $child = new $maintClass();
        $child->loadParamsAndArgs(
            $this->mSelf,
            $this->parameters->getOptions(),
            $this->parameters->getArgs()
        );
        if ( $this->mDb !== null ) {
            $child->setDB( $this->mDb );
        }
        if ( $this->lbFactory !== null ) {
            $child->setLBFactory( $this->lbFactory );
        }
 
        return $child;
    }
 
    public function setup() {
        // noop
    }
 
    public function memoryLimit() {
        return 'max';
    }
 
    public function clearParamsAndArgs() {
        $this->parameters->clear();
        $this->mInputLoaded = false;
    }
 
    public function setName( string $name ) {
        $this->mSelf = $name;
        $this->parameters->setName( $this->mSelf );
    }
 
    public function loadWithArgv( $argv ) {
        if ( $this->mDescription ) {
            $this->parameters->setDescription( $this->mDescription );
        }
 
        $this->parameters->loadWithArgv( $argv );
 
        if ( $this->parameters->hasErrors() ) {
            // Show errors and exit
            $this->maybeHelp( true );
        }
 
        $this->loadSpecialVars();
        $this->mInputLoaded = true;
    }
 
    public function loadParamsAndArgs( $self = null, $opts = null, $args = null ) {
        # If we were given opts or args, set those and return early
        if ( $self !== null || $opts !== null || $args !== null ) {
            if ( $self !== null ) {
                $this->mSelf = $self;
                $this->parameters->setName( $self );
            }
            $this->parameters->setOptionsAndArgs( $opts ?? [], $args ?? [] );
            $this->mInputLoaded = true;
        }
 
        # If we've already loaded input (either by user values or from $argv)
        # skip on loading it again.
        if ( $this->mInputLoaded ) {
            $this->loadSpecialVars();
 
            return;
        }
 
        global $argv;
        $this->mSelf = $argv[0];
        $this->parameters->setName( $this->mSelf );
        $this->loadWithArgv( array_slice( $argv, 1 ) );
    }
 
    public function validateParamsAndArgs() {
        $valid = $this->parameters->validate();
 
        $this->maybeHelp( !$valid );
    }
 
    protected function loadSpecialVars() {
        if ( $this->hasOption( 'dbuser' ) ) {
            $this->mDbUser = $this->getOption( 'dbuser' );
        }
        if ( $this->hasOption( 'dbpass' ) ) {
            $this->mDbPass = $this->getOption( 'dbpass' );
        }
        if ( $this->hasOption( 'quiet' ) ) {
            $this->mQuiet = true;
        }
        if ( $this->hasOption( 'batch-size' ) ) {
            $this->mBatchSize = intval( $this->getOption( 'batch-size' ) );
        }
    }
 
    protected function maybeHelp( $force = false ) {
        if ( $this->parameters->hasWarnings() && !$this->hasOption( 'help' ) ) {
            foreach ( $this->parameters->getWarnings() as $warning ) {
                $this->error( "WARNING: " . $warning );
            }
        }
 
        if ( !$force && !$this->hasOption( 'help' ) ) {
            return;
        }
 
        if ( $this->parameters->hasErrors() && !$this->hasOption( 'help' ) ) {
            foreach ( $this->parameters->getErrors() as $error ) {
                $this->error( "ERROR: " . $error );
            }
        }
 
        $this->showHelp();
        $this->fatalError( '' );
    }
 
    protected function showHelp() {
        $this->mQuiet = false;
        $help = $this->parameters->getHelp();
        $this->output( $help );
    }
 
    public function finalSetup( SettingsBuilder $settingsBuilder ) {
        $config = $settingsBuilder->getConfig();
        $overrides = [];
        $overrides['DBadminuser'] = $config->get( MainConfigNames::DBadminuser );
        $overrides['DBadminpassword'] = $config->get( MainConfigNames::DBadminpassword );
 
        # Turn off output buffering again, it might have been turned on in the settings files
        if ( ob_get_level() ) {
            ob_end_flush();
        }
 
        # Override $wgServer
        if ( $this->hasOption( 'server' ) ) {
            $overrides['Server'] = $this->getOption( 'server', $config->get( MainConfigNames::Server ) );
        }
 
        # If these were passed, use them
        if ( $this->mDbUser ) {
            $overrides['DBadminuser'] = $this->mDbUser;
        }
        if ( $this->mDbPass ) {
            $overrides['DBadminpassword'] = $this->mDbPass;
        }
 
        if ( $this->getDbType() == self::DB_ADMIN && isset( $overrides[ 'DBadminuser' ] ) ) {
            $overrides['DBuser'] = $overrides[ 'DBadminuser' ];
            $overrides['DBpassword'] = $overrides[ 'DBadminpassword' ];
 
            $dbServers = $config->get( MainConfigNames::DBservers );
            if ( $dbServers ) {
                foreach ( $dbServers as $i => $server ) {
                    $dbServers[$i]['user'] = $overrides['DBuser'];
                    $dbServers[$i]['password'] = $overrides['DBpassword'];
                }
                $overrides['DBservers'] = $dbServers;
            }
 
            $lbFactoryConf = $config->get( MainConfigNames::LBFactoryConf );
            if ( isset( $lbFactoryConf['serverTemplate'] ) ) {
                $lbFactoryConf['serverTemplate']['user'] = $overrides['DBuser'];
                $lbFactoryConf['serverTemplate']['password'] = $overrides['DBpassword'];
                $overrides['LBFactoryConf'] = $lbFactoryConf;
            }
 
            // TODO: once MediaWikiServices::getInstance() starts throwing exceptions
            // and not deprecation warnings for premature access to service container,
            // we can remove this line. This method is called before Setup.php,
            // so it would be guaranteed DBLoadBalancerFactory is not yet initialized.
            if ( MediaWikiServices::hasInstance() ) {
                $service = $this->getServiceContainer()->peekService( 'DBLoadBalancerFactory' );
                if ( $service ) {
                    $service->destroy();
                }
            }
        }
 
        $this->afterFinalSetup();
 
        $overrides['ShowExceptionDetails'] = true;
        $overrides['ShowHostname'] = true;
 
        ini_set( 'max_execution_time', '0' );
        $settingsBuilder->putConfigValues( $overrides );
    }
 
    protected function afterFinalSetup() {
    }
 
    public function purgeRedundantText( $delete = true ) {
        if ( $this->getConfig()->get( MainConfigNames::MiserMode ) ) {
            // Don't even try to run this on large wikis where it will hang ...
            $this->output( "Not trying to purge text records on miser-mode wiki.\n" );
            return;
        }
        # Data should come off the master, wrapped in a transaction
        $dbw = $this->getPrimaryDB();
        $this->beginTransactionRound( __METHOD__ );
 
        # Get "active" text records via the content table
        $cur = [];
        $this->output( 'Searching for active text records via contents table...' );
        $res = $dbw->newSelectQueryBuilder()
            ->select( 'content_address' )
            ->distinct()
            ->from( 'content' )
            ->caller( __METHOD__ )->fetchResultSet();
        $blobStore = $this->getServiceContainer()->getBlobStore();
        foreach ( $res as $row ) {
            // @phan-suppress-next-line PhanUndeclaredMethod
            $textId = $blobStore->getTextIdFromAddress( $row->content_address );
            if ( $textId ) {
                $cur[] = $textId;
            }
        }
        $this->output( "done.\n" );
 
        # Get the IDs of all text records not in these sets
        $this->output( 'Searching for inactive text records...' );
        $textTableQueryBuilder = $dbw->newSelectQueryBuilder()
            ->select( 'old_id' )
            ->distinct()
            ->from( 'text' );
        if ( count( $cur ) ) {
            $textTableQueryBuilder->where( $dbw->expr( 'old_id', '!=', $cur ) );
        }
        $res = $textTableQueryBuilder
            ->caller( __METHOD__ )
            ->fetchResultSet();
        $old = [];
        foreach ( $res as $row ) {
            $old[] = $row->old_id;
        }
        $this->output( "done.\n" );
 
        # Inform the user of what we're going to do
        $count = count( $old );
        $this->output( "$count inactive items found.\n" );
 
        # Delete as appropriate
        if ( $delete && $count ) {
            $this->output( 'Deleting...' );
            $dbw->newDeleteQueryBuilder()
                ->deleteFrom( 'text' )
                ->where( [ 'old_id' => $old ] )
                ->caller( __METHOD__ )
                ->execute();
            $this->output( "done.\n" );
        }
 
        $this->commitTransactionRound( __METHOD__ );
    }
 
    protected function getDir() {
        return __DIR__ . '/../';
    }
 
    protected function getDB( $db, $groups = [], $dbDomain = false ) {
        if ( $this->mDb === null ) {
            return $this->getLBFactory()
                ->getMainLB( $dbDomain )
                ->getMaintenanceConnectionRef( $db, $groups, $dbDomain );
        }
 
        return $this->mDb;
    }
 
    public function setDB( IMaintainableDatabase $db ) {
        $this->mDb = $db;
    }
 
    protected function getReplicaDB( string|false $virtualDomain = false ): IReadableDatabase {
        return $this->getLBFactory()->getReplicaDatabase( $virtualDomain );
    }
 
    protected function getPrimaryDB( string|false $virtualDomain = false ): IDatabase {
        return $this->getLBFactory()->getPrimaryDatabase( $virtualDomain );
    }
 
    public function setLBFactory( ILBFactory $lbFactory ) {
        $this->lbFactory = $lbFactory;
    }
 
    private function getLBFactory() {
        if ( $this->lbFactory === null ) {
            $this->lbFactory = $this->getServiceContainer()->getDBLoadBalancerFactory();
            if ( $this->hasOption( 'dbgroupdefault' ) ) {
                $this->lbFactory->setDefaultGroupName(
                    $this->getOption( 'dbgroupdefault', '' )
                );
            }
        }
 
        return $this->lbFactory;
    }
 
    protected function beginTransaction( IDatabase $dbw, $fname ) {
        $dbw->begin( $fname );
    }
 
    protected function commitTransaction( IDatabase $dbw, $fname ) {
        $dbw->commit( $fname );
 
        return $this->waitForReplication();
    }
 
    protected function rollbackTransaction( IDatabase $dbw, $fname ) {
        $dbw->rollback( $fname );
    }
 
    private function autoReconfigure( ILBFactory $lbFactory ): void {
        static $failedReconfigureCount = 0;
 
        try {
            $lbFactory->autoReconfigure();
            $failedReconfigureCount = 0;
        } catch ( ConfigException $e ) {
            $failedReconfigureCount++;
            if ( $failedReconfigureCount >= 10 ) {
                throw $e;
            }
            // Otherwise, try to keep going with the old config (T346971)
        }
    }
 
    protected function waitForReplication() {
        $lbFactory = $this->getLBFactory();
 
        $waitSucceeded = $lbFactory->waitForReplication(
            [ 'timeout' => 30, 'ifWritesSince' => $this->lastReplicationWait ]
        );
        $this->lastReplicationWait = microtime( true );
 
        $this->autoReconfigure( $lbFactory );
 
        // Periodically run any deferred updates that accumulate
        DeferredUpdates::tryOpportunisticExecute();
        // Flush stats periodically in long-running CLI scripts to avoid OOM (T181385)
        MediaWikiEntryPoint::emitBufferedStats(
            $this->getServiceContainer()->getStatsFactory()
        );
 
        return $waitSucceeded;
    }
 
    protected function beginTransactionRound( $fname ) {
        $lbFactory = $this->getLBFactory();
 
        $lbFactory->beginPrimaryChanges( $fname );
    }
 
    protected function commitTransactionRound( $fname ) {
        $lbFactory = $this->getLBFactory();
 
        $lbFactory->commitPrimaryChanges( $fname );
 
        $waitSucceeded = $lbFactory->waitForReplication(
            [ 'timeout' => 30, 'ifWritesSince' => $this->lastReplicationWait ]
        );
        $this->lastReplicationWait = microtime( true );
 
        // Periodically run any deferred updates that accumulate
        DeferredUpdates::tryOpportunisticExecute();
        // Flush stats periodically in long-running CLI scripts to avoid OOM (T181385)
        MediaWikiEntryPoint::emitBufferedStats(
            $this->getServiceContainer()->getStatsFactory()
        );
 
        $this->autoReconfigure( $lbFactory );
 
        return $waitSucceeded;
    }
 
    protected function rollbackTransactionRound( $fname ) {
        $lbFactory = $this->getLBFactory();
 
        $lbFactory->rollbackPrimaryChanges( $fname );
    }
 
    final protected function newBatchIterator( $source ): iterable {
        $batchSize = max( $this->getBatchSize(), 1 );
        if ( $source instanceof Closure ) {
            $iterable = $source();
        } else {
            $iterable = $source;
        }
 
        $entryBatch = [];
        foreach ( $iterable as $key => $entry ) {
            $entryBatch[$key] = $entry;
            if ( count( $entryBatch ) >= $batchSize ) {
                yield $entryBatch;
                $entryBatch = [];
            }
        }
        if ( $entryBatch ) {
            yield $entryBatch;
        }
    }
 
    protected function countDown( $seconds ) {
        if ( $this->isQuiet() ) {
            return;
        }
        for ( $i = $seconds; $i >= 0; $i-- ) {
            if ( $i != $seconds ) {
                $this->output( str_repeat( "\x08", strlen( (string)( $i + 1 ) ) ) );
            }
            $this->output( (string)$i );
            if ( $i ) {
                sleep( 1 );
            }
        }
        $this->output( "\n" );
    }
 
    public static function posix_isatty( $fd ) {
        if ( !function_exists( 'posix_isatty' ) ) {
            return !$fd;
        }
 
        return posix_isatty( $fd );
    }
 
    public static function readconsole( $prompt = '> ' ) {
        static $isatty = null;
        $isatty ??= self::posix_isatty( 0 /*STDIN*/ );
 
        if ( $isatty && function_exists( 'readline' ) ) {
            return readline( $prompt );
        }
 
        if ( $isatty ) {
            $st = self::readlineEmulation( $prompt );
        } elseif ( feof( STDIN ) ) {
            $st = false;
        } else {
            $st = fgets( STDIN, 1024 );
        }
        if ( $st === false ) {
            return false;
        }
 
        return trim( $st );
    }
 
    private static function readlineEmulation( $prompt ) {
        $bash = ExecutableFinder::findInDefaultPaths( 'bash' );
        if ( !wfIsWindows() && $bash ) {
            $encPrompt = Shell::escape( $prompt );
            $command = "read -er -p $encPrompt && echo \"\$REPLY\"";
            $result = Shell::command( $bash, '-c', $command )
                ->passStdin()
                ->forwardStderr()
                ->execute();
 
            if ( $result->getExitCode() == 0 ) {
                return $result->getStdout();
            }
 
            if ( $result->getExitCode() == 127 ) {
                // Couldn't execute bash even though we thought we saw it.
                // Shell probably spit out an error message, sorry :(
                // Fall through to fgets()...
            } else {
                // EOF/ctrl+D
                return false;
            }
        }
 
        // Fallback... we'll have no editing controls, EWWW
        if ( feof( STDIN ) ) {
            return false;
        }
        print $prompt;
 
        return fgets( STDIN, 1024 );
    }
 
    public static function getTermSize() {
        static $termSize = null;
 
        if ( $termSize !== null ) {
            return $termSize;
        }
 
        $default = [ 80, 50 ];
 
        if ( wfIsWindows() || Shell::isDisabled() ) {
            $termSize = $default;
 
            return $termSize;
        }
 
        // It's possible to get the screen size with VT-100 terminal escapes,
        // but reading the responses is not possible without setting raw mode
        // (unless you want to require the user to press enter), and that
        // requires an ioctl(), which we can't do. So we have to shell out to
        // something that can do the relevant syscalls. There are a few
        // options. Linux and Mac OS X both have "stty size" which does the
        // job directly.
        $result = Shell::command( 'stty', 'size' )->passStdin()->execute();
        if ( $result->getExitCode() !== 0 ||
            !preg_match( '/^(\d+) (\d+)$/', $result->getStdout(), $m )
        ) {
            $termSize = $default;
 
            return $termSize;
        }
 
        $termSize = [ intval( $m[2] ), intval( $m[1] ) ];
 
        return $termSize;
    }
 
    public static function requireTestsAutoloader() {
        require_once __DIR__ . '/../../tests/common/TestsAutoLoader.php';
    }
 
    protected function getHookContainer() {
        if ( !$this->hookContainer ) {
            $this->hookContainer = $this->getServiceContainer()->getHookContainer();
        }
        return $this->hookContainer;
    }
 
    protected function getHookRunner() {
        if ( !$this->hookRunner ) {
            $this->hookRunner = new HookRunner( $this->getHookContainer() );
        }
        return $this->hookRunner;
    }
 
    protected function parseIntList( $text ) {
        $ids = preg_split( '/[\s,;:|]+/', $text );
        $ids = array_map(
            static function ( $id ) {
                return (int)$id;
            },
            $ids
        );
        return array_filter( $ids );
    }
 
    protected function validateUserOption( $errorMsg ) {
        if ( $this->hasOption( "user" ) ) {
            $user = User::newFromName( $this->getOption( 'user' ) );
        } elseif ( $this->hasOption( "userid" ) ) {
            $user = User::newFromId( $this->getOption( 'userid' ) );
        } else {
            $this->fatalError( $errorMsg );
        }
        if ( !$user || !$user->isRegistered() ) {
            if ( $this->hasOption( "user" ) ) {
                $this->fatalError( "No such user: " . $this->getOption( 'user' ) );
            } elseif ( $this->hasOption( "userid" ) ) {
                $this->fatalError( "No such user id: " . $this->getOption( 'userid' ) );
            }
        }
 
        return $user;
    }
 
    protected function prompt( string $prompt, ?string $default = null ): ?string {
        $defaultText = $default === null ? ' > ' : " [{$default}] > ";
        $promptWithDefault = $prompt . $defaultText;
        $line = self::readconsole( $promptWithDefault );
        if ( $line === false ) {
            return $default;
        }
        if ( $line === '' ) {
            return $default;
        }
 
        return $line;
    }
 
    protected function promptYesNo( $prompt, $default = null ) {
        $defaultText = $default === null ? '' : ( $default ? 'Y' : 'n' );
        $line = self::readconsole( $prompt . " (Y/n) [$defaultText]" );
        if ( $line === false ) {
            return $default;
        }
        if ( $line === '' ) {
            return $default;
        }
 
        return strtolower( $line ) === 'y';
    }
}
 
class_alias( Maintenance::class, 'Maintenance' );