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