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