wikimedia/mediawiki-core

<?php
/**
 * Clean up user preferences from the database.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @author TyA <tya.wiki@gmail.com>
 * @author Chad <chad@wikimedia.org>
 * @see https://phabricator.wikimedia.org/T32976
 * @ingroup Maintenance
 */

// @codeCoverageIgnoreStart
require_once __DIR__ . '/Maintenance.php';
// @codeCoverageIgnoreEnd

use MediaWiki\MainConfigNames;
use MediaWiki\User\Options\UserOptionsLookup;
use Wikimedia\Rdbms\IExpression;
use Wikimedia\Rdbms\LikeValue;

/**
 * Maintenance script that removes unused preferences from the database.
 *
 * @ingroup Maintenance
 */
class CleanupPreferences extends Maintenance {
    public function __construct() {
        parent::__construct();
        $this->addDescription( 'Clean up hidden preferences or removed preferences' );
        $this->setBatchSize( 50 );
        $this->addOption( 'dry-run', 'Print debug info instead of actually deleting' );
        $this->addOption( 'hidden', 'Drop hidden preferences ($wgHiddenPrefs)' );
        $this->addOption( 'unknown',
            'Drop unknown preferences (not in $wgDefaultUserOptions or prefixed with "userjs-")' );
    }

    /**
     * We will do this in three passes
     *   1) The easiest is to drop the hidden preferences from the database. We
     *      don't actually want them
     *   2) Drop preference keys that we don't know about. They could've been
     *      removed from core, provided by a now-disabled extension, or the result
     *      of a bug. We don't want them.
     */
    public function execute() {
        $dbr = $this->getReplicaDB();
        $hidden = $this->hasOption( 'hidden' );
        $unknown = $this->hasOption( 'unknown' );

        if ( !$hidden && !$unknown ) {
            $this->output( "Did not select one of --hidden, --unknown, exiting\n" );
            return;
        }

        // Remove hidden prefs. Iterate over them to avoid the IN on a large table
        if ( $hidden ) {
            $hiddenPrefs = $this->getConfig()->get( MainConfigNames::HiddenPrefs );
            if ( !$hiddenPrefs ) {
                $this->output( "No hidden preferences, skipping\n" );
            }
            foreach ( $hiddenPrefs as $hiddenPref ) {
                $this->deleteByWhere(
                    $dbr,
                    'Dropping hidden preferences',
                    [ 'up_property' => $hiddenPref ]
                );
            }
        }

        // Remove unknown preferences. Special-case 'userjs-' as we can't control those names.
        if ( $unknown ) {
            $defaultUserOptions = $this->getServiceContainer()->getUserOptionsLookup()->getDefaultOptions( null );
            $where = [
                $dbr->expr( 'up_property', IExpression::NOT_LIKE,
                    new LikeValue( 'userjs-', $dbr->anyString() ) ),
                $dbr->expr( 'up_property', IExpression::NOT_LIKE,
                    new LikeValue( UserOptionsLookup::LOCAL_EXCEPTION_SUFFIX, $dbr->anyString() ) ),
                $dbr->expr( 'up_property', '!=', array_keys( $defaultUserOptions ) ),
            ];
            // Allow extensions to add to the where clause to prevent deletion of their own prefs.
            $this->getHookRunner()->onDeleteUnknownPreferences( $where, $dbr );
            $this->deleteByWhere( $dbr, 'Dropping unknown preferences', $where );
        }
    }

    private function deleteByWhere( $dbr, $startMessage, $where ) {
        $this->output( $startMessage . "...\n" );
        $dryRun = $this->hasOption( 'dry-run' );

        $iterator = new BatchRowIterator(
            $dbr,
            'user_properties',
            [ 'up_user', 'up_property' ],
            $this->getBatchSize()
        );
        if ( $dryRun ) {
            $iterator->setFetchColumns( [ 'up_user', 'up_property', 'up_value' ] );
        } else {
            $iterator->setFetchColumns( [ 'up_user', 'up_property' ] );
        }
        $iterator->addConditions( $where );
        $iterator->setCaller( __METHOD__ );

        $dbw = $this->getPrimaryDB();
        $total = 0;
        foreach ( $iterator as $batch ) {
            $numRows = count( $batch );
            $total += $numRows;
            // Progress or something
            $this->output( "..doing $numRows entries\n" );

            // Delete our batch, then wait
            $deleteWhere = [];
            foreach ( $batch as $row ) {
                if ( $dryRun ) {
                    $this->output(
                        "    DRY RUN, would drop: " .
                        "[up_user] => '{$row->up_user}' " .
                        "[up_property] => '{$row->up_property}' " .
                        "[up_value] => '{$row->up_value}'\n"
                    );
                    continue;
                }
                $deleteWhere[$row->up_user][$row->up_property] = true;
            }
            if ( $deleteWhere && !$dryRun ) {
                $dbw->newDeleteQueryBuilder()
                    ->deleteFrom( 'user_properties' )
                    ->where( $dbw->makeWhereFrom2d( $deleteWhere, 'up_user', 'up_property' ) )
                    ->caller( __METHOD__ )->execute();

                $this->waitForReplication();
            }
        }
        $this->output( "DONE! (handled $total entries)\n" );
    }
}

// @codeCoverageIgnoreStart
$maintClass = CleanupPreferences::class; // Tells it to run the class
require_once RUN_MAINTENANCE_IF_MAIN;
// @codeCoverageIgnoreEnd