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