populateRevisionLength.php

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<?php
require_once __DIR__ . '/Maintenance.php';
 
class PopulateRevisionLength extends LoggedUpdateMaintenance {
    public function __construct() {
        parent::__construct();
        $this->addDescription( 'Populates the rev_len and ar_len fields' );
        $this->setBatchSize( 200 );
    }
 
    protected function getUpdateKey() {
        return 'populate rev_len and ar_len';
    }
 
    public function doDBUpdates() {
        $dbw = $this->getDB( DB_PRIMARY );
        if ( !$dbw->tableExists( 'revision', __METHOD__ ) ) {
            $this->fatalError( "revision table does not exist" );
        } elseif ( !$dbw->tableExists( 'archive', __METHOD__ ) ) {
            $this->fatalError( "archive table does not exist" );
        } elseif ( !$dbw->fieldExists( 'revision', 'rev_len', __METHOD__ ) ) {
            $this->output( "rev_len column does not exist\n\n", true );
 
            return false;
        }
 
        $revisionStore = $this->getServiceContainer()->getRevisionStore();
 
        $this->output( "Populating rev_len column\n" );
        $rev = $this->doLenUpdates(
            'revision',
            'rev_id',
            'rev',
            $revisionStore->newSelectQueryBuilder( $this->getReplicaDB() )->joinComment()
        );
 
        $this->output( "Populating ar_len column\n" );
        $ar = $this->doLenUpdates(
            'archive',
            'ar_id',
            'ar',
            $revisionStore->newArchiveSelectQueryBuilder( $this->getReplicaDB() )->joinComment()
        );
 
        $this->output( "rev_len and ar_len population complete "
            . "[$rev revision rows, $ar archive rows].\n" );
 
        return true;
    }
 
    protected function doLenUpdates( $table, $idCol, $prefix, $queryBuilder ) {
        $dbr = $this->getReplicaDB();
        $dbw = $this->getPrimaryDB();
        $batchSize = $this->getBatchSize();
        $start = $dbw->newSelectQueryBuilder()
            ->select( "MIN($idCol)" )
            ->from( $table )
            ->caller( __METHOD__ )->fetchField();
        $end = $dbw->newSelectQueryBuilder()
            ->select( "MAX($idCol)" )
            ->from( $table )
            ->caller( __METHOD__ )->fetchField();
        if ( !$start || !$end ) {
            $this->output( "...$table table seems to be empty.\n" );
 
            return 0;
        }
 
        # Do remaining chunks
        $blockStart = intval( $start );
        $blockEnd = intval( $start ) + $batchSize - 1;
        $count = 0;
 
        while ( $blockStart <= $end ) {
            $this->output( "...doing $idCol from $blockStart to $blockEnd\n" );
 
            $res = $queryBuilder
                ->where( [
                    "$idCol >= $blockStart",
                    "$idCol <= $blockEnd",
                    $dbr->expr( "{$prefix}_len", '=', null )
                        ->orExpr(
                            $dbr->expr( "{$prefix}_len", '=', 0 )
                                // sha1( "" )
                                ->and( "{$prefix}_sha1", '!=', 'phoiac9h4m842xq45sp7s6u21eteeq1' )
                        ),
                ] )
                ->caller( __METHOD__ )->fetchResultSet();
 
            if ( $res->numRows() > 0 ) {
                $this->beginTransaction( $dbw, __METHOD__ );
                # Go through and update rev_len from these rows.
                foreach ( $res as $row ) {
                    if ( $this->upgradeRow( $row, $table, $idCol, $prefix ) ) {
                        $count++;
                    }
                }
                $this->commitTransaction( $dbw, __METHOD__ );
            }
 
            $blockStart += $batchSize;
            $blockEnd += $batchSize;
        }
 
        return $count;
    }
 
    protected function upgradeRow( $row, $table, $idCol, $prefix ) {
        $dbw = $this->getPrimaryDB();
 
        $revFactory = $this->getServiceContainer()->getRevisionFactory();
        if ( $table === 'archive' ) {
            $revRecord = $revFactory->newRevisionFromArchiveRow( $row );
        } else {
            $revRecord = $revFactory->newRevisionFromRow( $row );
        }
 
        if ( !$revRecord ) {
            # This should not happen, but sometimes does (T22757)
            $id = $row->$idCol;
            $this->output( "RevisionRecord of $table $id unavailable!\n" );
 
            return false;
        }
 
        # Update the row...
        $dbw->newUpdateQueryBuilder()
            ->update( $table )
            ->set( [ "{$prefix}_len" => $revRecord->getSize() ] )
            ->where( [ $idCol => $row->$idCol ] )
            ->caller( __METHOD__ )->execute();
 
        return true;
    }
}
 
$maintClass = PopulateRevisionLength::class;
require_once RUN_MAINTENANCE_IF_MAIN;