--- /dev/null
+<?php
+
+require_once( dirname( __FILE__ ) . '/../Maintenance.php' );
+
+class FixBug20757 extends Maintenance {
+ var $batchSize = 10000;
+ var $mapCache = array();
+ var $mapCacheSize = 0;
+ var $maxMapCacheSize = 1000000;
+
+ function __construct() {
+ parent::__construct();
+ $this->mDescription = 'Script to fix bug 20757 assuming that blob_tracking is intact';
+ $this->addOption( 'dry-run', 'Report only' );
+ $this->addOption( 'start', 'old_id to start at', false, true );
+ }
+
+ function execute() {
+ $dbr = wfGetDB( DB_SLAVE );
+ $dbw = wfGetDB( DB_MASTER );
+
+ $dryRun = $this->getOption( 'dry-run' );
+ if ( $dryRun ) {
+ print "Dry run only.\n";
+ }
+
+ $startId = $this->getOption( 'start', 0 );
+ $numGood = 0;
+ $numFixed = 0;
+ $numBad = 0;
+
+ $totalRevs = $dbr->selectField( 'text', 'MAX(old_id)', false, __METHOD__ );
+
+ while ( true ) {
+ print "ID: $startId / $totalRevs\r";
+
+ $res = $dbr->select(
+ 'text',
+ array( 'old_id', 'old_flags', 'old_text' ),
+ array(
+ 'old_id > ' . intval( $startId ),
+ 'old_flags LIKE \'%object%\' AND old_flags NOT LIKE \'%external%\'',
+ 'LOWER(CONVERT(LEFT(old_text,22) USING latin1)) = \'o:15:"historyblobstub"\'',
+ ),
+ __METHOD__,
+ array(
+ 'ORDER BY' => 'old_id',
+ 'LIMIT' => $this->batchSize,
+ )
+ );
+
+ if ( !$res->numRows() ) {
+ break;
+ }
+
+ $secondaryIds = array();
+ $stubs = array();
+
+ foreach ( $res as $row ) {
+ $startId = $row->old_id;
+
+ // Basic sanity checks
+ $obj = unserialize( $row->old_text );
+ if ( $obj === false ) {
+ print "{$row->old_id}: unrecoverable: cannot unserialize\n";
+ ++$numBad;
+ continue;
+ }
+
+ if ( !is_object( $obj ) ) {
+ print "{$row->old_id}: unrecoverable: unserialized to type " .
+ gettype( $obj ) . ", possible double-serialization\n";
+ ++$numBad;
+ continue;
+ }
+
+ if ( strtolower( get_class( $obj ) ) !== 'historyblobstub' ) {
+ print "{$row->old_id}: unrecoverable: unexpected object class " .
+ get_class( $obj ) . "\n";
+ ++$numBad;
+ continue;
+ }
+
+ // Process flags
+ $flags = explode( ',', $row->old_flags );
+ if ( in_array( 'utf-8', $flags ) || in_array( 'utf8', $flags ) ) {
+ $legacyEncoding = false;
+ } else {
+ $legacyEncoding = true;
+ }
+
+ // Queue the stub for future batch processing
+ $id = intval( $obj->mOldId );
+ $secondaryIds[] = $id;
+ $stubs[$row->old_id] = array(
+ 'legacyEncoding' => $legacyEncoding,
+ 'secondaryId' => $id,
+ 'hash' => $obj->mHash,
+ );
+ }
+
+ $secondaryIds = array_unique( $secondaryIds );
+
+ if ( !count( $secondaryIds ) ) {
+ continue;
+ }
+
+ // Run the batch query on blob_tracking
+ $res = $dbr->select(
+ 'blob_tracking',
+ '*',
+ array(
+ 'bt_text_id' => $secondaryIds,
+ ),
+ __METHOD__
+ );
+ $trackedBlobs = array();
+ foreach ( $res as $row ) {
+ $trackedBlobs[$row->bt_text_id] = $row;
+ }
+
+ // Process the stubs
+ $stubsToFix = array();
+ foreach ( $stubs as $primaryId => $stub ) {
+ $secondaryId = $stub['secondaryId'];
+ if ( !isset( $trackedBlobs[$secondaryId] ) ) {
+ // No tracked blob. Work out what went wrong
+ $secondaryRow = $dbr->selectRow(
+ 'text',
+ array( 'old_flags', 'old_text' ),
+ array( 'old_id' => $secondaryId ),
+ __METHOD__
+ );
+ if ( !$secondaryRow ) {
+ print "$primaryId: unrecoverable: secondary row is missing\n";
+ ++$numBad;
+ } elseif ( $this->isUnbrokenStub( $stub, $secondaryRow ) ) {
+ // Not broken yet, and not in the tracked clusters so it won't get
+ // broken by the current RCT run.
+ ++$numGood;
+ } elseif ( strpos( $secondaryRow->old_flags, 'external' ) !== false ) {
+ print "$primaryId: unrecoverable: secondary gone to {$secondaryRow->old_text}\n";
+ ++$numBad;
+ } else {
+ print "$primaryId: unrecoverable: miscellaneous corruption of secondary row\n";
+ ++$numBad;
+ }
+ unset( $stubs[$primaryId] );
+ continue;
+ }
+ $trackRow = $trackedBlobs[$secondaryId];
+
+ // Check that the specified text really is available in the tracked source row
+ $url = "DB://{$trackRow->bt_cluster}/{$trackRow->bt_blob_id}/{$stub['hash']}";
+ $text = ExternalStore::fetchFromURL( $url );
+ if ( $text === false ) {
+ print "$primaryId: unrecoverable: source text missing\n";
+ ++$numBad;
+ unset( $stubs[$primaryId] );
+ continue;
+ }
+ if ( md5( $text ) !== $stub['hash'] ) {
+ print "$primaryId: unrecoverable: content hashes do not match\n";
+ ++$numBad;
+ unset( $stubs[$primaryId] );
+ continue;
+ }
+
+ // Find the page_id and rev_id
+ // The page is probably the same as the page of the secondary row
+ $pageId = intval( $trackRow->bt_page );
+ if ( !$pageId ) {
+ $revId = $pageId = 0;
+ } else {
+ $revId = $this->findTextIdInPage( $pageId, $primaryId );
+ if ( !$revId ) {
+ // Actually an orphan
+ $pageId = $revId = 0;
+ }
+ }
+
+ $newFlags = $stub['legacyEncoding'] ? 'external' : 'external,utf-8';
+
+ if ( !$dryRun ) {
+ // Reset the text row to point to the original copy
+ $dbw->begin();
+ $dbw->update(
+ 'text',
+ // SET
+ array(
+ 'old_flags' => $newFlags,
+ 'old_text' => $url
+ ),
+ // WHERE
+ array( 'old_id' => $primaryId ),
+ __METHOD__
+ );
+
+ // Add a blob_tracking row so that the new reference can be recompressed
+ // without needing to run trackBlobs.php again
+ $dbw->insert( 'blob_tracking',
+ array(
+ 'bt_page' => $pageId,
+ 'bt_rev_id' => $revId,
+ 'bt_text_id' => $primaryId,
+ 'bt_cluster' => $trackRow->bt_cluster,
+ 'bt_blob_id' => $trackRow->bt_blob_id,
+ 'bt_cgz_hash' => $stub['hash'],
+ 'bt_new_url' => null,
+ 'bt_moved' => 0,
+ ),
+ __METHOD__
+ );
+ $dbw->commit();
+ $this->waitForSlaves();
+ }
+
+ print "$primaryId: resolved to $url\n";
+ ++$numFixed;
+ }
+ }
+
+ print "\n";
+ print "Fixed: $numFixed\n";
+ print "Unrecoverable: $numBad\n";
+ print "Good stubs: $numGood\n";
+ }
+
+ function waitForSlaves() {
+ static $iteration = 0;
+ ++$iteration;
+ if ( ++$iteration > 50 == 0 ) {
+ wfWaitForSlaves( 5 );
+ $iteration = 0;
+ }
+ }
+
+ function findTextIdInPage( $pageId, $textId ) {
+ $ids = $this->getRevTextMap( $pageId );
+ if ( !isset( $ids[$textId] ) ) {
+ return null;
+ } else {
+ return $ids[$textId];
+ }
+ }
+
+ function getRevTextMap( $pageId ) {
+ if ( !isset( $this->mapCache[$pageId] ) ) {
+ // Limit cache size
+ while ( $this->mapCacheSize > $this->maxMapCacheSize ) {
+ $key = key( $this->mapCache );
+ $this->mapCacheSize -= count( $this->mapCache[$key] );
+ unset( $this->mapCache[$key] );
+ }
+
+ $dbr = wfGetDB( DB_SLAVE );
+ $map = array();
+ $res = $dbr->select( 'revision',
+ array( 'rev_id', 'rev_text_id' ),
+ array( 'rev_page' => $pageId ),
+ __METHOD__
+ );
+ foreach ( $res as $row ) {
+ $map[$row->rev_text_id] = $row->rev_id;
+ }
+ $this->mapCache[$pageId] = $map;
+ $this->mapCacheSize += count( $map );
+ }
+ return $this->mapCache[$pageId];
+ }
+
+ /**
+ * This is based on part of HistoryBlobStub::getText().
+ * Determine if the text can be retrieved from the row in the normal way.
+ */
+ function isUnbrokenStub( $stub, $secondaryRow ) {
+ $flags = explode( ',', $secondaryRow->old_flags );
+ $text = $secondaryRow->old_text;
+ if( in_array( 'external', $flags ) ) {
+ $url = $text;
+ @list( /* $proto */ , $path ) = explode( '://', $url, 2 );
+ if ( $path == "" ) {
+ return false;
+ }
+ $text = ExternalStore::fetchFromUrl( $url );
+ }
+ if( !in_array( 'object', $flags ) ) {
+ return false;
+ }
+
+ if( in_array( 'gzip', $flags ) ) {
+ $obj = unserialize( gzinflate( $text ) );
+ } else {
+ $obj = unserialize( $text );
+ }
+
+ if( !is_object( $obj ) ) {
+ // Correct for old double-serialization bug.
+ $obj = unserialize( $obj );
+ }
+
+ if ( !is_object( $obj ) ) {
+ return false;
+ }
+
+ $obj->uncompress();
+ $text = $obj->getItem( $stub['hash'] );
+ return $text !== false;
+ }
+}
+
+$maintClass = 'FixBug20757';
+require_once( DO_MAINTENANCE );
+
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff