populateArchiveRevId.php

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<?php
use Wikimedia\Rdbms\IDatabase;
 
require_once __DIR__ . '/Maintenance.php';
 
class PopulateArchiveRevId extends LoggedUpdateMaintenance {
    public function __construct() {
        parent::__construct();
        $this->addDescription( 'Populate ar_rev_id in pre-1.5 rows' );
        $this->setBatchSize( 100 );
    }
 
    protected function getUpdateKey() {
        return __CLASS__;
    }
 
    protected function doDBUpdates() {
        $this->output( "Populating ar_rev_id...\n" );
        $dbw = $this->getDB( DB_MASTER );
 
        // Quick exit if there are no rows needing updates.
        $any = $dbw->selectField(
            'archive',
            'ar_id',
            [ 'ar_rev_id' => null ],
            __METHOD__
        );
        if ( !$any ) {
            $this->output( "Completed ar_rev_id population, 0 rows updated.\n" );
            return true;
        }
 
        $rev = $this->makeDummyRevisionRow( $dbw );
        $count = 0;
        while ( true ) {
            wfWaitForSlaves();
 
            $arIds = $dbw->selectFieldValues(
                'archive',
                'ar_id',
                [ 'ar_rev_id' => null ],
                __METHOD__,
                [ 'LIMIT' => $this->getBatchSize(), 'ORDER BY' => [ 'ar_id' ] ]
            );
            if ( !$arIds ) {
                $this->output( "Completed ar_rev_id population, $count rows updated.\n" );
                return true;
            }
 
            try {
                $updates = $dbw->doAtomicSection( __METHOD__, function ( $dbw, $fname ) use ( $arIds, $rev ) {
                    // Create new rev_ids by inserting dummy rows into revision and then deleting them.
                    $dbw->insert( 'revision', array_fill( 0, count( $arIds ), $rev ), $fname );
                    $revIds = $dbw->selectFieldValues(
                        'revision',
                        'rev_id',
                        [ 'rev_timestamp' => $rev['rev_timestamp'] ],
                        $fname
                    );
                    if ( !is_array( $revIds ) ) {
                        throw new UnexpectedValueException( 'Failed to insert dummy revisions' );
                    }
                    if ( count( $revIds ) !== count( $arIds ) ) {
                        throw new UnexpectedValueException(
                            'Tried to insert ' . count( $arIds ) . ' dummy revisions, but found '
                            . count( $revIds ) . ' matching rows.'
                        );
                    }
                    $dbw->delete( 'revision', [ 'rev_id' => $revIds ], $fname );
 
                    return array_combine( $arIds, $revIds );
                } );
            } catch ( UnexpectedValueException $ex ) {
                $this->fatalError( $ex->getMessage() );
            }
 
            foreach ( $updates as $arId => $revId ) {
                $dbw->update(
                    'archive',
                    [ 'ar_rev_id' => $revId ],
                    [ 'ar_id' => $arId, 'ar_rev_id' => null ],
                    __METHOD__
                );
                $count += $dbw->affectedRows();
            }
 
            $min = min( array_keys( $updates ) );
            $max = max( array_keys( $updates ) );
            $this->output( " ... $min-$max\n" );
        }
    }
 
    private function makeDummyRevisionRow( IDatabase $dbw ) {
        $ts = $dbw->timestamp( '11111111111111' );
        $mainPage = Title::newMainPage();
        if ( !$mainPage ) {
            $this->fatalError( 'Main page does not exist' );
        }
        $pageId = $mainPage->getArticleId();
        if ( !$pageId ) {
            $this->fatalError( $mainPage->getPrefixedText() . ' has no ID' );
        }
        $rev = $dbw->selectRow(
            'revision',
            '*',
            [ 'rev_page' => $pageId ],
            __METHOD__,
            [ 'ORDER BY' => 'rev_timestamp ASC' ]
        );
        if ( !$rev ) {
            $this->fatalError( $mainPage->getPrefixedText() . ' has no revisions' );
        }
        unset( $rev->rev_id );
        $rev = (array)$rev;
        $rev['rev_timestamp'] = $ts;
        if ( isset( $rev['rev_user'] ) ) {
            $rev['rev_user'] = 0;
            $rev['rev_user_text'] = '0.0.0.0';
        }
        if ( isset( $rev['rev_comment'] ) ) {
            $rev['rev_comment'] = 'Dummy row';
        }
 
        $any = $dbw->selectField(
            'revision',
            'rev_id',
            [ 'rev_timestamp' => $ts ],
            __METHOD__
        );
        if ( $any ) {
            $this->fatalError( "... Why does your database contain a revision dated $ts?" );
        }
 
        return $rev;
    }
}
 
$maintClass = "PopulateArchiveRevId";
require_once RUN_MAINTENANCE_IF_MAIN;