wikimedia / mediawiki

maintenance/storage/resolveStubs.php

<?php

For compatibility and reusability of your code, PSR1 recommends that a file should introduce either new symbols (like classes, functions, etc.) or have side-effects (like outputting something, or including other files), but not both at the same time. The first symbol is defined on line 37 and the first side effect is on line 26.

/**
 * Convert history stubs that point to an external row to direct external
 * pointers.
 *
 * 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 ExternalStorage
 */

if ( !defined( 'MEDIAWIKI' ) ) {
	$optionsWithArgs = [ 'm' ];

	require_once __DIR__ . '/../commandLine.inc';

	resolveStubs();
}

/**
 * Convert history stubs that point to an external row to direct
 * external pointers
 */
function resolveStubs() {
	$fname = 'resolveStubs';

	$dbr = wfGetDB( DB_REPLICA );
	$maxID = $dbr->selectField( 'text', 'MAX(old_id)', false, $fname );
	$blockSize = 10000;
	$numBlocks = intval( $maxID / $blockSize ) + 1;

	for ( $b = 0; $b < $numBlocks; $b++ ) {
		wfWaitForSlaves();

The function wfWaitForSlaves() has been deprecated with message: since 1.27 Use LBFactory::waitForReplication

		printf( "%5.2f%%\n", $b / $numBlocks * 100 );
		$start = intval( $maxID / $numBlocks ) * $b + 1;
		$end = intval( $maxID / $numBlocks ) * ( $b + 1 );

		$res = $dbr->select( 'text', [ 'old_id', 'old_text', 'old_flags' ],
			"old_id>=$start AND old_id<=$end " .
			"AND old_flags LIKE '%object%' AND old_flags NOT LIKE '%external%' " .
			'AND LOWER(CONVERT(LEFT(old_text,22) USING latin1)) = \'o:15:"historyblobstub"\'',
			$fname );
		foreach ( $res as $row ) {
			resolveStub( $row->old_id, $row->old_text, $row->old_flags );
		}
	}
	print "100%\n";
}

/**
 * Resolve a history stub
 * @param int $id
 * @param string $stubText
 * @param string $flags
 */
function resolveStub( $id, $stubText, $flags ) {
	$fname = 'resolveStub';

	$stub = unserialize( $stubText );
	$flags = explode( ',', $flags );

	$dbr = wfGetDB( DB_REPLICA );
	$dbw = wfGetDB( DB_MASTER );

	if ( strtolower( get_class( $stub ) ) !== 'historyblobstub' ) {
		print "Error found object of class " . get_class( $stub ) . ", expecting historyblobstub\n";

		return;
	}

	# Get the (maybe) external row
	$externalRow = $dbr->selectRow(
		'text',
		[ 'old_text' ],
		[
			'old_id' => $stub->mOldId,
			'old_flags' . $dbr->buildLike( $dbr->anyString(), 'external', $dbr->anyString() )
		],
		$fname
	);

	if ( !$externalRow ) {
		# Object wasn't external
		return;
	}

	# Preserve the legacy encoding flag, but switch from object to external
	if ( in_array( 'utf-8', $flags ) ) {
		$newFlags = 'external,utf-8';
	} else {
		$newFlags = 'external';
	}

	# Update the row
	# print "oldid=$id\n";
	$dbw->update( 'text',
		[ /* SET */
			'old_flags' => $newFlags,
			'old_text' => $externalRow->old_text . '/' . $stub->mHash
		],
		[ /* WHERE */
			'old_id' => $id
		], $fname
	);
}