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