ChangedTablesTracker.php

Go to the documentation of this file.

<?php
 
namespace Wikimedia\Rdbms;
 
use RuntimeException;
 
class ChangedTablesTracker {
    private const TRACKED_VERBS = [ 'INSERT', 'UPDATE', 'REPLACE' ];
    private static bool $trackingEnabled = false;
    private static array $tableMap = [];
 
    public static function startTracking(): void {
        if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
            throw new RuntimeException( "This class is internal and should only be used in tests." );
        }
        if ( self::$trackingEnabled ) {
            throw new RuntimeException( "Tracking is already enabled" );
        }
        self::$trackingEnabled = true;
        self::$tableMap = [];
    }
 
    public static function getTables( string $domainId ): array {
        $tableMap = self::$tableMap[$domainId] ?? [];
        return array_keys( $tableMap );
    }
 
    public static function stopTracking(): void {
        if ( !self::$trackingEnabled ) {
            throw new RuntimeException( "Tracking is not enabled" );
        }
        self::$tableMap = [];
        self::$trackingEnabled = false;
    }
 
    public static function recordQuery( DatabaseDomain $domain, Query $query ): void {
        if ( !self::$trackingEnabled ) {
            return;
        }
        if ( !$query->isWriteQuery() ) {
            return;
        }
        $domainId = $domain->getId();
        $queryVerb = $query->getVerb();
        $tableName = $query->getWriteTable();
        if ( $tableName === null ) {
            return;
        }
        if ( $queryVerb === 'DROP' ) {
            // Special case: if a table is being dropped, forget about it.
            unset( self::$tableMap[$domainId][$tableName] );
            return;
        }
        if ( !in_array( $queryVerb, self::TRACKED_VERBS, true ) ) {
            return;
        }
 
        self::$tableMap[$domainId][$tableName] = true;
    }
}