maintenance/storage/checkStorage.php

   1 <?php
   2 /**
   3  * Fsck for MediaWiki
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Maintenance ExternalStorage
  22  */
  23
  24 use MediaWiki\MediaWikiServices;
  25 use MediaWiki\Revision\RevisionRecord;
  26 use MediaWiki\Shell\Shell;
  27
  28 if ( !defined( 'MEDIAWIKI' ) ) {
  29         $optionsWithoutArgs = [ 'fix' ];
  30         require_once __DIR__ . '/../commandLine.inc';
  31
  32         $cs = new CheckStorage;
  33         $fix = isset( $options['fix'] );
  34         $xml = $args[0] ?? false;
  35         $cs->check( $fix, $xml );
  36 }
  37
  38 // ----------------------------------------------------------------------------------
  39
  40 /**
  41  * Maintenance script to do various checks on external storage.
  42  *
  43  * @fixme this should extend the base Maintenance class
  44  * @ingroup Maintenance ExternalStorage
  45  */
  46 class CheckStorage {
  47         const CONCAT_HEADER = 'O:27:"concatenatedgziphistoryblob"';
  48         public $oldIdMap, $errors;
  49         /** @var ExternalStoreDB */
  50         public $dbStore = null;
  51
  52         public $errorDescriptions = [
  53                 'restore text' => 'Damaged text, need to be restored from a backup',
  54                 'restore revision' => 'Damaged revision row, need to be restored from a backup',
  55                 'unfixable' => 'Unexpected errors with no automated fixing method',
  56                 'fixed' => 'Errors already fixed',
  57                 'fixable' => 'Errors which would already be fixed if --fix was specified',
  58         ];
  59
  60         function check( $fix = false, $xml = '' ) {
  61                 global $wgMultiContentRevisionSchemaMigrationStage;
  62
  63                 $dbr = wfGetDB( DB_REPLICA );
  64                 if ( $fix ) {
  65                         print "Checking, will fix errors if possible...\n";
  66                 } else {
  67                         print "Checking...\n";
  68                 }
  69                 $maxRevId = $dbr->selectField( 'revision', 'MAX(rev_id)', '', __METHOD__ );
  70                 $chunkSize = 1000;
  71                 $flagStats = [];
  72                 $objectStats = [];
  73                 $knownFlags = [ 'external', 'gzip', 'object', 'utf-8' ];
  74                 $this->errors = [
  75                         'restore text' => [],
  76                         'restore revision' => [],
  77                         'unfixable' => [],
  78                         'fixed' => [],
  79                         'fixable' => [],
  80                 ];
  81
  82                 for ( $chunkStart = 1; $chunkStart < $maxRevId; $chunkStart += $chunkSize ) {
  83                         $chunkEnd = $chunkStart + $chunkSize - 1;
  84                         // print "$chunkStart of $maxRevId\n";
  85
  86                         $this->oldIdMap = [];
  87                         $dbr->ping();
  88
  89                         // Fetch revision rows
  90                         if ( $wgMultiContentRevisionSchemaMigrationStage & SCHEMA_COMPAT_READ_OLD ) {
  91                                 $res = $dbr->select( 'revision', [ 'rev_id', 'rev_text_id' ],
  92                                         [ "rev_id BETWEEN $chunkStart AND $chunkEnd" ], __METHOD__ );
  93                                 foreach ( $res as $row ) {
  94                                         if ( !isset( $this->oldIdMap[ $row->rev_text_id ] ) ) {
  95                                                 $this->oldIdMap[ $row->rev_text_id ] = [ $row->rev_id ];
  96                                         } elseif ( !in_array( $row->rev_id, $this->oldIdMap[ $row->rev_text_id ] ) ) {
  97                                                 $this->oldIdMap[ $row->rev_text_id ][] = $row->rev_id;
  98                                         }
  99                                 }
 100                         } else {
 101                                 $res = $dbr->select(
 102                                         [ 'slots', 'content' ],
 103                                         [ 'slot_revision_id', 'content_address' ],
 104                                         [ "slot_revision_id BETWEEN $chunkStart AND $chunkEnd" ],
 105                                         __METHOD__,
 106                                         [],
 107                                         [ 'content' => [ 'INNER JOIN', [ 'content_id = slot_content_id' ] ] ]
 108                                 );
 109                                 $blobStore = MediaWikiServices::getInstance()->getBlobStore();
 110                                 foreach ( $res as $row ) {
 111                                         $textId = $blobStore->getTextIdFromAddress( $row->content_address );
 112                                         if ( $textId ) {
 113                                                 if ( !isset( $this->oldIdMap[$textId] ) ) {
 114                                                         $this->oldIdMap[ $textId ] = [ $row->slot_revision_id ];
 115                                                 } elseif ( !in_array( $row->slot_revision_id, $this->oldIdMap[$textId] ) ) {
 116                                                         $this->oldIdMap[ $textId ][] = $row->slot_revision_id;
 117                                                 }
 118                                         }
 119                                 }
 120                         }
 121
 122                         if ( !count( $this->oldIdMap ) ) {
 123                                 continue;
 124                         }
 125
 126                         // Fetch old_flags
 127                         $missingTextRows = $this->oldIdMap;
 128                         $externalRevs = [];
 129                         $objectRevs = [];
 130                         $res = $dbr->select(
 131                                 'text',
 132                                 [ 'old_id', 'old_flags' ],
 133                                 [ 'old_id' => array_keys( $this->oldIdMap ) ],
 134                                 __METHOD__
 135                         );
 136                         foreach ( $res as $row ) {
 137                                 /**
 138                                  * @var int $flags
 139                                  */
 140                                 $flags = $row->old_flags;
 141                                 $id = $row->old_id;
 142
 143                                 // Create flagStats row if it doesn't exist
 144                                 $flagStats = $flagStats + [ $flags => 0 ];
 145                                 // Increment counter
 146                                 $flagStats[$flags]++;
 147
 148                                 // Not missing
 149                                 unset( $missingTextRows[$row->old_id] );
 150
 151                                 // Check for external or object
 152                                 if ( $flags == '' ) {
 153                                         $flagArray = [];
 154                                 } else {
 155                                         $flagArray = explode( ',', $flags );
 156                                 }
 157                                 if ( in_array( 'external', $flagArray ) ) {
 158                                         $externalRevs[] = $id;
 159                                 } elseif ( in_array( 'object', $flagArray ) ) {
 160                                         $objectRevs[] = $id;
 161                                 }
 162
 163                                 // Check for unrecognised flags
 164                                 if ( $flags == '0' ) {
 165                                         // This is a known bug from 2004
 166                                         // It's safe to just erase the old_flags field
 167                                         if ( $fix ) {
 168                                                 $this->addError( 'fixed', "Warning: old_flags set to 0", $id );
 169                                                 $dbw = wfGetDB( DB_MASTER );
 170                                                 $dbw->ping();
 171                                                 $dbw->update( 'text', [ 'old_flags' => '' ],
 172                                                         [ 'old_id' => $id ], __METHOD__ );
 173                                                 echo "Fixed\n";
 174                                         } else {
 175                                                 $this->addError( 'fixable', "Warning: old_flags set to 0", $id );
 176                                         }
 177                                 } elseif ( count( array_diff( $flagArray, $knownFlags ) ) ) {
 178                                         $this->addError( 'unfixable', "Error: invalid flags field \"$flags\"", $id );
 179                                 }
 180                         }
 181
 182                         // Output errors for any missing text rows
 183                         foreach ( $missingTextRows as $oldId => $revIds ) {
 184                                 $this->addError( 'restore revision', "Error: missing text row", $oldId );
 185                         }
 186
 187                         // Verify external revisions
 188                         $externalConcatBlobs = [];
 189                         $externalNormalBlobs = [];
 190                         if ( count( $externalRevs ) ) {
 191                                 $res = $dbr->select(
 192                                         'text',
 193                                         [ 'old_id', 'old_flags', 'old_text' ],
 194                                         [ 'old_id' => $externalRevs ],
 195                                         __METHOD__
 196                                 );
 197                                 foreach ( $res as $row ) {
 198                                         $urlParts = explode( '://', $row->old_text, 2 );
 199                                         if ( count( $urlParts ) !== 2 || $urlParts[1] == '' ) {
 200                                                 $this->addError( 'restore text', "Error: invalid URL \"{$row->old_text}\"", $row->old_id );
 201                                                 continue;
 202                                         }
 203                                         list( $proto, ) = $urlParts;
 204                                         if ( $proto != 'DB' ) {
 205                                                 $this->addError(
 206                                                         'restore text',
 207                                                         "Error: invalid external protocol \"$proto\"",
 208                                                         $row->old_id );
 209                                                 continue;
 210                                         }
 211                                         $path = explode( '/', $row->old_text );
 212                                         $cluster = $path[2];
 213                                         $id = $path[3];
 214                                         if ( isset( $path[4] ) ) {
 215                                                 $externalConcatBlobs[$cluster][$id][] = $row->old_id;
 216                                         } else {
 217                                                 $externalNormalBlobs[$cluster][$id][] = $row->old_id;
 218                                         }
 219                                 }
 220                         }
 221
 222                         // Check external concat blobs for the right header
 223                         $this->checkExternalConcatBlobs( $externalConcatBlobs );
 224
 225                         // Check external normal blobs for existence
 226                         if ( count( $externalNormalBlobs ) ) {
 227                                 if ( is_null( $this->dbStore ) ) {
 228                                         $esFactory = MediaWikiServices::getInstance()->getExternalStoreFactory();
 229                                         $this->dbStore = $esFactory->getStore( 'DB' );
 230                                 }
 231                                 foreach ( $externalConcatBlobs as $cluster => $xBlobIds ) {
 232                                         $blobIds = array_keys( $xBlobIds );
 233                                         $extDb =& $this->dbStore->getSlave( $cluster );
 234                                         $blobsTable = $this->dbStore->getTable( $extDb );
 235                                         $res = $extDb->select( $blobsTable,
 236                                                 [ 'blob_id' ],
 237                                                 [ 'blob_id' => $blobIds ],
 238                                                 __METHOD__
 239                                         );
 240                                         foreach ( $res as $row ) {
 241                                                 unset( $xBlobIds[$row->blob_id] );
 242                                         }
 243                                         // Print errors for missing blobs rows
 244                                         foreach ( $xBlobIds as $blobId => $oldId ) {
 245                                                 $this->addError(
 246                                                         'restore text',
 247                                                         "Error: missing target $blobId for one-part ES URL",
 248                                                         $oldId );
 249                                         }
 250                                 }
 251                         }
 252
 253                         // Check local objects
 254                         $dbr->ping();
 255                         $concatBlobs = [];
 256                         $curIds = [];
 257                         if ( count( $objectRevs ) ) {
 258                                 $headerLength = 300;
 259                                 $res = $dbr->select(
 260                                         'text',
 261                                         [ 'old_id', 'old_flags', "LEFT(old_text, $headerLength) AS header" ],
 262                                         [ 'old_id' => $objectRevs ],
 263                                         __METHOD__
 264                                 );
 265                                 foreach ( $res as $row ) {
 266                                         $oldId = $row->old_id;
 267                                         $matches = [];
 268                                         if ( !preg_match( '/^O:(\d+):"(\w+)"/', $row->header, $matches ) ) {
 269                                                 $this->addError( 'restore text', "Error: invalid object header", $oldId );
 270                                                 continue;
 271                                         }
 272
 273                                         $className = strtolower( $matches[2] );
 274                                         if ( strlen( $className ) != $matches[1] ) {
 275                                                 $this->addError(
 276                                                         'restore text',
 277                                                         "Error: invalid object header, wrong class name length",
 278                                                         $oldId
 279                                                 );
 280                                                 continue;
 281                                         }
 282
 283                                         $objectStats = $objectStats + [ $className => 0 ];
 284                                         $objectStats[$className]++;
 285
 286                                         switch ( $className ) {
 287                                                 case 'concatenatedgziphistoryblob':
 288                                                         // Good
 289                                                         break;
 290                                                 case 'historyblobstub':
 291                                                 case 'historyblobcurstub':
 292                                                         if ( strlen( $row->header ) == $headerLength ) {
 293                                                                 $this->addError( 'unfixable', "Error: overlong stub header", $oldId );
 294                                                                 break;
 295                                                         }
 296                                                         $stubObj = unserialize( $row->header );
 297                                                         if ( !is_object( $stubObj ) ) {
 298                                                                 $this->addError( 'restore text', "Error: unable to unserialize stub object", $oldId );
 299                                                                 break;
 300                                                         }
 301                                                         if ( $className == 'historyblobstub' ) {
 302                                                                 $concatBlobs[$stubObj->mOldId][] = $oldId;
 303                                                         } else {
 304                                                                 $curIds[$stubObj->mCurId][] = $oldId;
 305                                                         }
 306                                                         break;
 307                                                 default:
 308                                                         $this->addError( 'unfixable', "Error: unrecognised object class \"$className\"", $oldId );
 309                                         }
 310                                 }
 311                         }
 312
 313                         // Check local concat blob validity
 314                         $externalConcatBlobs = [];
 315                         if ( count( $concatBlobs ) ) {
 316                                 $headerLength = 300;
 317                                 $res = $dbr->select(
 318                                         'text',
 319                                         [ 'old_id', 'old_flags', "LEFT(old_text, $headerLength) AS header" ],
 320                                         [ 'old_id' => array_keys( $concatBlobs ) ],
 321                                         __METHOD__
 322                                 );
 323                                 foreach ( $res as $row ) {
 324                                         $flags = explode( ',', $row->old_flags );
 325                                         if ( in_array( 'external', $flags ) ) {
 326                                                 // Concat blob is in external storage?
 327                                                 if ( in_array( 'object', $flags ) ) {
 328                                                         $urlParts = explode( '/', $row->header );
 329                                                         if ( $urlParts[0] != 'DB:' ) {
 330                                                                 $this->addError(
 331                                                                         'unfixable',
 332                                                                         "Error: unrecognised external storage type \"{$urlParts[0]}",
 333                                                                         $row->old_id
 334                                                                 );
 335                                                         } else {
 336                                                                 $cluster = $urlParts[2];
 337                                                                 $id = $urlParts[3];
 338                                                                 if ( !isset( $externalConcatBlobs[$cluster][$id] ) ) {
 339                                                                         $externalConcatBlobs[$cluster][$id] = [];
 340                                                                 }
 341                                                                 $externalConcatBlobs[$cluster][$id] = array_merge(
 342                                                                         $externalConcatBlobs[$cluster][$id], $concatBlobs[$row->old_id]
 343                                                                 );
 344                                                         }
 345                                                 } else {
 346                                                         $this->addError(
 347                                                                 'unfixable',
 348                                                                 "Error: invalid flags \"{$row->old_flags}\" on concat bulk row {$row->old_id}",
 349                                                                 $concatBlobs[$row->old_id] );
 350                                                 }
 351                                         } elseif ( strcasecmp(
 352                                                 substr( $row->header, 0, strlen( self::CONCAT_HEADER ) ),
 353                                                 self::CONCAT_HEADER
 354                                         ) ) {
 355                                                 $this->addError(
 356                                                         'restore text',
 357                                                         "Error: Incorrect object header for concat bulk row {$row->old_id}",
 358                                                         $concatBlobs[$row->old_id]
 359                                                 );
 360                                         } # else good
 361
 362                                         unset( $concatBlobs[$row->old_id] );
 363                                 }
 364                         }
 365
 366                         // Check targets of unresolved stubs
 367                         $this->checkExternalConcatBlobs( $externalConcatBlobs );
 368                         // next chunk
 369                 }
 370
 371                 print "\n\nErrors:\n";
 372                 foreach ( $this->errors as $name => $errors ) {
 373                         if ( count( $errors ) ) {
 374                                 $description = $this->errorDescriptions[$name];
 375                                 echo "$description: " . implode( ',', array_keys( $errors ) ) . "\n";
 376                         }
 377                 }
 378
 379                 if ( count( $this->errors['restore text'] ) && $fix ) {
 380                         if ( (string)$xml !== '' ) {
 381                                 $this->restoreText( array_keys( $this->errors['restore text'] ), $xml );
 382                         } else {
 383                                 echo "Can't fix text, no XML backup specified\n";
 384                         }
 385                 }
 386
 387                 print "\nFlag statistics:\n";
 388                 $total = array_sum( $flagStats );
 389                 foreach ( $flagStats as $flag => $count ) {
 390                         printf( "%-30s %10d %5.2f%%\n", $flag, $count, $count / $total * 100 );
 391                 }
 392                 print "\nLocal object statistics:\n";
 393                 $total = array_sum( $objectStats );
 394                 foreach ( $objectStats as $className => $count ) {
 395                         printf( "%-30s %10d %5.2f%%\n", $className, $count, $count / $total * 100 );
 396                 }
 397         }
 398
 399         function addError( $type, $msg, $ids ) {
 400                 if ( is_array( $ids ) && count( $ids ) == 1 ) {
 401                         $ids = reset( $ids );
 402                 }
 403                 if ( is_array( $ids ) ) {
 404                         $revIds = [];
 405                         foreach ( $ids as $id ) {
 406                                 $revIds = array_unique( array_merge( $revIds, $this->oldIdMap[$id] ) );
 407                         }
 408                         print "$msg in text rows " . implode( ', ', $ids ) .
 409                                 ", revisions " . implode( ', ', $revIds ) . "\n";
 410                 } else {
 411                         $id = $ids;
 412                         $revIds = $this->oldIdMap[$id];
 413                         if ( count( $revIds ) == 1 ) {
 414                                 print "$msg in old_id $id, rev_id {$revIds[0]}\n";
 415                         } else {
 416                                 print "$msg in old_id $id, revisions " . implode( ', ', $revIds ) . "\n";
 417                         }
 418                 }
 419                 $this->errors[$type] = $this->errors[$type] + array_flip( $revIds );
 420         }
 421
 422         function checkExternalConcatBlobs( $externalConcatBlobs ) {
 423                 if ( !count( $externalConcatBlobs ) ) {
 424                         return;
 425                 }
 426
 427                 if ( is_null( $this->dbStore ) ) {
 428                         $esFactory = MediaWikiServices::getInstance()->getExternalStoreFactory();
 429                         $this->dbStore = $esFactory->getStore( 'DB' );
 430                 }
 431
 432                 foreach ( $externalConcatBlobs as $cluster => $oldIds ) {
 433                         $blobIds = array_keys( $oldIds );
 434                         $extDb =& $this->dbStore->getSlave( $cluster );
 435                         $blobsTable = $this->dbStore->getTable( $extDb );
 436                         $headerLength = strlen( self::CONCAT_HEADER );
 437                         $res = $extDb->select( $blobsTable,
 438                                 [ 'blob_id', "LEFT(blob_text, $headerLength) AS header" ],
 439                                 [ 'blob_id' => $blobIds ],
 440                                 __METHOD__
 441                         );
 442                         foreach ( $res as $row ) {
 443                                 if ( strcasecmp( $row->header, self::CONCAT_HEADER ) ) {
 444                                         $this->addError(
 445                                                 'restore text',
 446                                                 "Error: invalid header on target $cluster/{$row->blob_id} of two-part ES URL",
 447                                                 $oldIds[$row->blob_id]
 448                                         );
 449                                 }
 450                                 unset( $oldIds[$row->blob_id] );
 451                         }
 452
 453                         // Print errors for missing blobs rows
 454                         foreach ( $oldIds as $blobId => $oldIds2 ) {
 455                                 $this->addError(
 456                                         'restore text',
 457                                         "Error: missing target $cluster/$blobId for two-part ES URL",
 458                                         $oldIds2
 459                                 );
 460                         }
 461                 }
 462         }
 463
 464         function restoreText( $revIds, $xml ) {
 465                 global $wgDBname;
 466                 $tmpDir = wfTempDir();
 467
 468                 if ( !count( $revIds ) ) {
 469                         return;
 470                 }
 471
 472                 print "Restoring text from XML backup...\n";
 473
 474                 $revFileName = "$tmpDir/broken-revlist-$wgDBname";
 475                 $filteredXmlFileName = "$tmpDir/filtered-$wgDBname.xml";
 476
 477                 // Write revision list
 478                 if ( !file_put_contents( $revFileName, implode( "\n", $revIds ) ) ) {
 479                         echo "Error writing revision list, can't restore text\n";
 480
 481                         return;
 482                 }
 483
 484                 // Run mwdumper
 485                 echo "Filtering XML dump...\n";
 486                 $exitStatus = 0;
 487                 passthru( 'mwdumper ' .
 488                         Shell::escape(
 489                                 "--output=file:$filteredXmlFileName",
 490                                 "--filter=revlist:$revFileName",
 491                                 $xml
 492                         ), $exitStatus
 493                 );
 494
 495                 if ( $exitStatus ) {
 496                         echo "mwdumper died with exit status $exitStatus\n";
 497
 498                         return;
 499                 }
 500
 501                 $file = fopen( $filteredXmlFileName, 'r' );
 502                 if ( !$file ) {
 503                         echo "Unable to open filtered XML file\n";
 504
 505                         return;
 506                 }
 507
 508                 $dbr = wfGetDB( DB_REPLICA );
 509                 $dbw = wfGetDB( DB_MASTER );
 510                 $dbr->ping();
 511                 $dbw->ping();
 512
 513                 $source = new ImportStreamSource( $file );
 514                 $importer = new WikiImporter(
 515                         $source,
 516                         MediaWikiServices::getInstance()->getMainConfig()
 517                 );
 518                 $importer->setRevisionCallback( [ $this, 'importRevision' ] );
 519                 $importer->setNoticeCallback( function ( $msg, $params ) {
 520                         echo wfMessage( $msg, $params )->text() . "\n";
 521                 } );
 522                 $importer->doImport();
 523         }
 524
 525         function importRevision( &$revision, &$importer ) {
 526                 $id = $revision->getID();
 527                 $content = $revision->getContent( RevisionRecord::RAW );
 528                 $id = $id ?: '';
 529
 530                 if ( $content === null ) {
 531                         echo "Revision $id is broken, we have no content available\n";
 532
 533                         return;
 534                 }
 535
 536                 $text = $content->serialize();
 537                 if ( $text === '' ) {
 538                         // This is what happens if the revision was broken at the time the
 539                         // dump was made. Unfortunately, it also happens if the revision was
 540                         // legitimately blank, so there's no way to tell the difference. To
 541                         // be safe, we'll skip it and leave it broken
 542
 543                         echo "Revision $id is blank in the dump, may have been broken before export\n";
 544
 545                         return;
 546                 }
 547
 548                 if ( !$id ) {
 549                         // No ID, can't import
 550                         echo "No id tag in revision, can't import\n";
 551
 552                         return;
 553                 }
 554
 555                 // Find text row again
 556                 $dbr = wfGetDB( DB_REPLICA );
 557                 $oldId = $dbr->selectField( 'revision', 'rev_text_id', [ 'rev_id' => $id ], __METHOD__ );
 558                 if ( !$oldId ) {
 559                         echo "Missing revision row for rev_id $id\n";
 560
 561                         return;
 562                 }
 563
 564                 // Compress the text
 565                 $flags = Revision::compressRevisionText( $text );
 566
 567                 // Update the text row
 568                 $dbw = wfGetDB( DB_MASTER );
 569                 $dbw->update( 'text',
 570                         [ 'old_flags' => $flags, 'old_text' => $text ],
 571                         [ 'old_id' => $oldId ],
 572                         __METHOD__, [ 'LIMIT' => 1 ]
 573                 );
 574
 575                 // Remove it from the unfixed list and add it to the fixed list
 576                 unset( $this->errors['restore text'][$id] );
 577                 $this->errors['fixed'][$id] = true;
 578         }
 579 }