Current File : //proc/thread-self/root/www/varak.net/wiki.varak.net/maintenance/populateArchiveRevId.php
<?php
/**
* Populate ar_rev_id in pre-1.5 rows
*
* 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
* @ingroup Maintenance
*/
use Wikimedia\Rdbms\DBQueryError;
use Wikimedia\Rdbms\IDatabase;
require_once __DIR__ . '/Maintenance.php';
/**
* Maintenance script that populares archive.ar_rev_id in old rows
*
* @ingroup Maintenance
* @since 1.31
*/
class PopulateArchiveRevId extends LoggedUpdateMaintenance {
/** @var array|null Dummy revision row */
private static $dummyRev = null;
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 );
self::checkMysqlAutoIncrementBug( $dbw );
// 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;
}
$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;
}
$count += self::reassignArRevIds( $dbw, $arIds, [ 'ar_rev_id' => null ] );
$min = min( $arIds );
$max = max( $arIds );
$this->output( " ... $min-$max\n" );
}
}
/**
* Check for (and work around) a MySQL auto-increment bug
*
* (T202032) MySQL until 8.0 and MariaDB until some version after 10.1.34
* don't save the auto-increment value to disk, so on server restart it
* might reuse IDs from deleted revisions. We can fix that with an insert
* with an explicit rev_id value, if necessary.
*
* @param IDatabase $dbw
*/
public static function checkMysqlAutoIncrementBug( IDatabase $dbw ) {
if ( $dbw->getType() !== 'mysql' ) {
return;
}
if ( !self::$dummyRev ) {
self::$dummyRev = self::makeDummyRevisionRow( $dbw );
}
$ok = false;
while ( !$ok ) {
try {
$dbw->doAtomicSection( __METHOD__, function ( $dbw, $fname ) {
$dbw->insert( 'revision', self::$dummyRev, $fname );
$id = $dbw->insertId();
$toDelete[] = $id;
$maxId = max(
(int)$dbw->selectField( 'archive', 'MAX(ar_rev_id)', [], $fname ),
(int)$dbw->selectField( 'slots', 'MAX(slot_revision_id)', [], $fname )
);
if ( $id <= $maxId ) {
$dbw->insert( 'revision', [ 'rev_id' => $maxId + 1 ] + self::$dummyRev, $fname );
$toDelete[] = $maxId + 1;
}
$dbw->delete( 'revision', [ 'rev_id' => $toDelete ], $fname );
} );
$ok = true;
} catch ( DBQueryError $e ) {
if ( $e->errno != 1062 ) { // 1062 is "duplicate entry", ignore it and retry
throw $e;
}
}
}
}
/**
* Assign new ar_rev_ids to a set of ar_ids.
* @param IDatabase $dbw
* @param int[] $arIds
* @param array $conds Extra conditions for the update
* @return int Number of updated rows
*/
public static function reassignArRevIds( IDatabase $dbw, array $arIds, array $conds = [] ) {
if ( !self::$dummyRev ) {
self::$dummyRev = self::makeDummyRevisionRow( $dbw );
}
$updates = $dbw->doAtomicSection( __METHOD__, function ( $dbw, $fname ) use ( $arIds ) {
// Create new rev_ids by inserting dummy rows into revision and then deleting them.
$dbw->insert( 'revision', array_fill( 0, count( $arIds ), self::$dummyRev ), $fname );
$revIds = $dbw->selectFieldValues(
'revision',
'rev_id',
[ 'rev_timestamp' => self::$dummyRev['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 );
} );
$count = 0;
foreach ( $updates as $arId => $revId ) {
$dbw->update(
'archive',
[ 'ar_rev_id' => $revId ],
[ 'ar_id' => $arId ] + $conds,
__METHOD__
);
$count += $dbw->affectedRows();
}
return $count;
}
/**
* Construct a dummy revision table row to use for reserving IDs
*
* The row will have a wildly unlikely timestamp, and possibly a generic
* user and comment, but will otherwise be derived from a revision on the
* wiki's main page or some other revision in the database.
*
* @param IDatabase $dbw
* @return array
*/
private static function makeDummyRevisionRow( IDatabase $dbw ) {
$ts = $dbw->timestamp( '11111111111111' );
$rev = null;
$mainPage = Title::newMainPage();
$pageId = $mainPage ? $mainPage->getArticleId() : null;
if ( $pageId ) {
$rev = $dbw->selectRow(
'revision',
'*',
[ 'rev_page' => $pageId ],
__METHOD__,
[ 'ORDER BY' => 'rev_timestamp ASC' ]
);
}
if ( !$rev ) {
// No main page? Let's see if there are any revisions at all
$rev = $dbw->selectRow(
'revision',
'*',
[],
__METHOD__,
[ 'ORDER BY' => 'rev_timestamp ASC' ]
);
}
if ( !$rev ) {
// Since no revisions are available to copy, generate a dummy
// revision to a dummy page, then rollback the commit
wfDebug( __METHOD__ . ": No revisions are available to copy\n" );
$dbw->begin();
// Make a title and revision and insert them
$title = Title::newFromText( "PopulateArchiveRevId_4b05b46a81e29" );
$page = WikiPage::factory( $title );
$updater = $page->newPageUpdater(
User::newSystemUser( 'Maintenance script', [ 'steal' => true ] )
);
$updater->setContent(
'main',
ContentHandler::makeContent( "Content for dummy rev", $title )
);
$updater->saveRevision(
CommentStoreComment::newUnsavedComment( 'dummy rev summary' ),
EDIT_NEW | EDIT_SUPPRESS_RC
);
// get the revision row just inserted
$rev = $dbw->selectRow(
'revision',
'*',
[],
__METHOD__,
[ 'ORDER BY' => 'rev_timestamp ASC' ]
);
$dbw->rollback();
}
if ( !$rev ) {
// This should never happen.
throw new UnexpectedValueException(
'No revisions are available to copy, and one couldn\'t be created'
);
}
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 ) {
throw new UnexpectedValueException( "... Why does your database contain a revision dated $ts?" );
}
return $rev;
}
}
$maintClass = "PopulateArchiveRevId";
require_once RUN_MAINTENANCE_IF_MAIN;
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