1<?php 2/** 3 * Compress the text of a wiki. 4 * 5 * Usage: 6 * 7 * Non-wikimedia 8 * php compressOld.php [options...] 9 * 10 * Wikimedia 11 * php compressOld.php <database> [options...] 12 * 13 * Options are: 14 * -t <type> set compression type to either: 15 * gzip: compress revisions independently 16 * concat: concatenate revisions and compress in chunks (default) 17 * -c <chunk-size> maximum number of revisions in a concat chunk 18 * -b <begin-date> earliest date to check for uncompressed revisions 19 * -e <end-date> latest revision date to compress 20 * -s <startid> the id to start from (referring to the text table for 21 * type gzip, and to the page table for type concat) 22 * -n <endid> the page_id to stop at (only when using concat compression type) 23 * --extdb <cluster> store specified revisions in an external cluster (untested) 24 * 25 * This program is free software; you can redistribute it and/or modify 26 * it under the terms of the GNU General Public License as published by 27 * the Free Software Foundation; either version 2 of the License, or 28 * (at your option) any later version. 29 * 30 * This program is distributed in the hope that it will be useful, 31 * but WITHOUT ANY WARRANTY; without even the implied warranty of 32 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 33 * GNU General Public License for more details. 34 * 35 * You should have received a copy of the GNU General Public License along 36 * with this program; if not, write to the Free Software Foundation, Inc., 37 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 38 * http://www.gnu.org/copyleft/gpl.html 39 * 40 * @file 41 * @ingroup Maintenance ExternalStorage 42 */ 43use MediaWiki\MediaWikiServices; 44use MediaWiki\Revision\SlotRecord; 45 46require_once __DIR__ . '/../Maintenance.php'; 47 48/** 49 * Maintenance script that compress the text of a wiki. 50 * 51 * @ingroup Maintenance ExternalStorage 52 */ 53class CompressOld extends Maintenance { 54 public function __construct() { 55 parent::__construct(); 56 $this->addDescription( 'Compress the text of a wiki' ); 57 $this->addOption( 'type', 'Set compression type to either: gzip|concat', false, true, 't' ); 58 $this->addOption( 59 'chunksize', 60 'Maximum number of revisions in a concat chunk', 61 false, 62 true, 63 'c' 64 ); 65 $this->addOption( 66 'begin-date', 67 'Earliest date to check for uncompressed revisions', 68 false, 69 true, 70 'b' 71 ); 72 $this->addOption( 'end-date', 'Latest revision date to compress', false, true, 'e' ); 73 $this->addOption( 74 'startid', 75 'The id to start from (gzip -> text table, concat -> page table)', 76 false, 77 true, 78 's' 79 ); 80 $this->addOption( 81 'extdb', 82 'Store specified revisions in an external cluster (untested)', 83 false, 84 true 85 ); 86 $this->addOption( 87 'endid', 88 'The page_id to stop at (only when using concat compression type)', 89 false, 90 true, 91 'n' 92 ); 93 } 94 95 public function execute() { 96 global $wgDBname; 97 if ( !function_exists( "gzdeflate" ) ) { 98 $this->fatalError( "You must enable zlib support in PHP to compress old revisions!\n" . 99 "Please see https://www.php.net/manual/en/ref.zlib.php\n" ); 100 } 101 102 $type = $this->getOption( 'type', 'concat' ); 103 $chunkSize = $this->getOption( 'chunksize', 20 ); 104 $startId = $this->getOption( 'startid', 0 ); 105 $beginDate = $this->getOption( 'begin-date', '' ); 106 $endDate = $this->getOption( 'end-date', '' ); 107 $extDB = $this->getOption( 'extdb', '' ); 108 $endId = $this->getOption( 'endid', false ); 109 110 if ( $type != 'concat' && $type != 'gzip' ) { 111 $this->error( "Type \"{$type}\" not supported" ); 112 } 113 114 if ( $extDB != '' ) { 115 $this->output( "Compressing database {$wgDBname} to external cluster {$extDB}\n" 116 . str_repeat( '-', 76 ) . "\n\n" ); 117 } else { 118 $this->output( "Compressing database {$wgDBname}\n" 119 . str_repeat( '-', 76 ) . "\n\n" ); 120 } 121 122 $success = true; 123 if ( $type == 'concat' ) { 124 $success = $this->compressWithConcat( $startId, $chunkSize, $beginDate, 125 $endDate, $extDB, $endId ); 126 } else { 127 $this->compressOldPages( $startId, $extDB ); 128 } 129 130 if ( $success ) { 131 $this->output( "Done.\n" ); 132 } 133 } 134 135 /** 136 * Fetch the text row-by-row to 'compressPage' function for compression. 137 * 138 * @param int $start 139 * @param string $extdb 140 */ 141 private function compressOldPages( $start = 0, $extdb = '' ) { 142 $chunksize = 50; 143 $this->output( "Starting from old_id $start...\n" ); 144 $dbw = $this->getDB( DB_PRIMARY ); 145 do { 146 $res = $dbw->select( 147 'text', 148 [ 'old_id', 'old_flags', 'old_text' ], 149 "old_id>=$start", 150 __METHOD__, 151 [ 'ORDER BY' => 'old_id', 'LIMIT' => $chunksize, 'FOR UPDATE' ] 152 ); 153 154 if ( $res->numRows() == 0 ) { 155 break; 156 } 157 158 $last = $start; 159 160 foreach ( $res as $row ) { 161 # print " {$row->old_id} - {$row->old_namespace}:{$row->old_title}\n"; 162 $this->compressPage( $row, $extdb ); 163 $last = $row->old_id; 164 } 165 166 $start = $last + 1; # Deletion may leave long empty stretches 167 $this->output( "$start...\n" ); 168 } while ( true ); 169 } 170 171 /** 172 * Compress the text in gzip format. 173 * 174 * @param stdClass $row 175 * @param string $extdb 176 * @return bool 177 */ 178 private function compressPage( $row, $extdb ) { 179 if ( strpos( $row->old_flags, 'gzip' ) !== false 180 || strpos( $row->old_flags, 'object' ) !== false 181 ) { 182 # print "Already compressed row {$row->old_id}\n"; 183 return false; 184 } 185 $dbw = $this->getDB( DB_PRIMARY ); 186 $flags = $row->old_flags ? "{$row->old_flags},gzip" : "gzip"; 187 $compress = gzdeflate( $row->old_text ); 188 189 # Store in external storage if required 190 if ( $extdb !== '' ) { 191 $esFactory = MediaWikiServices::getInstance()->getExternalStoreFactory(); 192 /** @var ExternalStoreDB $storeObj */ 193 $storeObj = $esFactory->getStore( 'DB' ); 194 $compress = $storeObj->store( $extdb, $compress ); 195 if ( $compress === false ) { 196 $this->error( "Unable to store object" ); 197 198 return false; 199 } 200 } 201 202 # Update text row 203 $dbw->update( 'text', 204 [ /* SET */ 205 'old_flags' => $flags, 206 'old_text' => $compress 207 ], [ /* WHERE */ 208 'old_id' => $row->old_id 209 ], __METHOD__, 210 [ 'LIMIT' => 1 ] 211 ); 212 213 return true; 214 } 215 216 /** 217 * Compress the text in chunks after concatenating the revisions. 218 * 219 * @param int $startId 220 * @param int $maxChunkSize 221 * @param string $beginDate 222 * @param string $endDate 223 * @param string $extdb 224 * @param bool|int $maxPageId 225 * @return bool 226 */ 227 private function compressWithConcat( $startId, $maxChunkSize, $beginDate, 228 $endDate, $extdb = "", $maxPageId = false 229 ) { 230 $dbr = $this->getDB( DB_REPLICA ); 231 $dbw = $this->getDB( DB_PRIMARY ); 232 233 # Set up external storage 234 if ( $extdb != '' ) { 235 $esFactory = MediaWikiServices::getInstance()->getExternalStoreFactory(); 236 /** @var ExternalStoreDB $storeObj */ 237 $storeObj = $esFactory->getStore( 'DB' ); 238 } 239 240 $blobStore = MediaWikiServices::getInstance() 241 ->getBlobStoreFactory() 242 ->newSqlBlobStore(); 243 244 # Get all articles by page_id 245 if ( !$maxPageId ) { 246 $maxPageId = $dbr->selectField( 'page', 'max(page_id)', '', __METHOD__ ); 247 } 248 $this->output( "Starting from $startId of $maxPageId\n" ); 249 $pageConds = []; 250 251 /* 252 if ( $exclude_ns0 ) { 253 print "Excluding main namespace\n"; 254 $pageConds[] = 'page_namespace<>0'; 255 } 256 if ( $queryExtra ) { 257 $pageConds[] = $queryExtra; 258 } 259 */ 260 261 # For each article, get a list of revisions which fit the criteria 262 263 # No recompression, use a condition on old_flags 264 # Don't compress object type entities, because that might produce data loss when 265 # overwriting bulk storage concat rows. Don't compress external references, because 266 # the script doesn't yet delete rows from external storage. 267 $conds = [ 268 'old_flags NOT ' . $dbr->buildLike( $dbr->anyString(), 'object', $dbr->anyString() ) 269 . ' AND old_flags NOT ' 270 . $dbr->buildLike( $dbr->anyString(), 'external', $dbr->anyString() ) 271 ]; 272 273 if ( $beginDate ) { 274 if ( !preg_match( '/^\d{14}$/', $beginDate ) ) { 275 $this->error( "Invalid begin date \"$beginDate\"\n" ); 276 277 return false; 278 } 279 $conds[] = "rev_timestamp>'" . $beginDate . "'"; 280 } 281 if ( $endDate ) { 282 if ( !preg_match( '/^\d{14}$/', $endDate ) ) { 283 $this->error( "Invalid end date \"$endDate\"\n" ); 284 285 return false; 286 } 287 $conds[] = "rev_timestamp<'" . $endDate . "'"; 288 } 289 290 $slotRoleStore = MediaWikiServices::getInstance()->getSlotRoleStore(); 291 $tables = [ 'revision', 'slots', 'content', 'text' ]; 292 $conds = array_merge( [ 293 'rev_id=slot_revision_id', 294 'slot_role_id=' . $slotRoleStore->getId( SlotRecord::MAIN ), 295 'content_id=slot_content_id', 296 'SUBSTRING(content_address, 1, 3)=' . $dbr->addQuotes( 'tt:' ), 297 'SUBSTRING(content_address, 4)=old_id', 298 ], $conds ); 299 300 $fields = [ 'rev_id', 'old_id', 'old_flags', 'old_text' ]; 301 $revLoadOptions = 'FOR UPDATE'; 302 303 # Don't work with current revisions 304 # Don't lock the page table for update either -- TS 2006-04-04 305 # $tables[] = 'page'; 306 # $conds[] = 'page_id=rev_page AND rev_id != page_latest'; 307 308 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory(); 309 310 for ( $pageId = $startId; $pageId <= $maxPageId; $pageId++ ) { 311 $lbFactory->waitForReplication(); 312 313 # Wake up 314 $dbr->ping(); 315 316 # Get the page row 317 $pageRes = $dbr->select( 'page', 318 [ 'page_id', 'page_namespace', 'page_title', 'page_latest' ], 319 $pageConds + [ 'page_id' => $pageId ], __METHOD__ ); 320 if ( $pageRes->numRows() == 0 ) { 321 continue; 322 } 323 $pageRow = $dbr->fetchObject( $pageRes ); 324 325 # Display progress 326 $titleObj = Title::makeTitle( $pageRow->page_namespace, $pageRow->page_title ); 327 $this->output( "$pageId\t" . $titleObj->getPrefixedDBkey() . " " ); 328 329 # Load revisions 330 $revRes = $dbw->select( $tables, $fields, 331 array_merge( [ 332 'rev_page' => $pageRow->page_id, 333 # Don't operate on the current revision 334 # Use < instead of <> in case the current revision has changed 335 # since the page select, which wasn't locking 336 'rev_id < ' . (int)$pageRow->page_latest 337 ], $conds ), 338 __METHOD__, 339 $revLoadOptions 340 ); 341 $revs = []; 342 foreach ( $revRes as $revRow ) { 343 $revs[] = $revRow; 344 } 345 346 if ( count( $revs ) < 2 ) { 347 # No revisions matching, no further processing 348 $this->output( "\n" ); 349 continue; 350 } 351 352 # For each chunk 353 $i = 0; 354 while ( $i < count( $revs ) ) { 355 if ( $i < count( $revs ) - $maxChunkSize ) { 356 $thisChunkSize = $maxChunkSize; 357 } else { 358 $thisChunkSize = count( $revs ) - $i; 359 } 360 361 $chunk = new ConcatenatedGzipHistoryBlob(); 362 $stubs = []; 363 $this->beginTransaction( $dbw, __METHOD__ ); 364 $usedChunk = false; 365 $primaryOldid = $revs[$i]->old_id; 366 367 # Get the text of each revision and add it to the object 368 for ( $j = 0; $j < $thisChunkSize && $chunk->isHappy(); $j++ ) { 369 $oldid = $revs[$i + $j]->old_id; 370 371 # Get text. We do not need the full `extractBlob` since the query is built 372 # to fetch non-externalstore blobs. 373 $text = $blobStore->decompressData( 374 $revs[$i + $j]->old_text, 375 explode( ',', $revs[$i + $j]->old_flags ) 376 ); 377 378 if ( $text === false ) { 379 $this->error( "\nError, unable to get text in old_id $oldid" ); 380 # $dbw->delete( 'old', [ 'old_id' => $oldid ] ); 381 } 382 383 if ( $extdb == "" && $j == 0 ) { 384 $chunk->setText( $text ); 385 $this->output( '.' ); 386 } else { 387 # Don't make a stub if it's going to be longer than the article 388 # Stubs are typically about 100 bytes 389 if ( strlen( $text ) < 120 ) { 390 $stub = false; 391 $this->output( 'x' ); 392 } else { 393 $stub = new HistoryBlobStub( $chunk->addItem( $text ) ); 394 $stub->setLocation( $primaryOldid ); 395 $stub->setReferrer( $oldid ); 396 $this->output( '.' ); 397 $usedChunk = true; 398 } 399 $stubs[$j] = $stub; 400 } 401 } 402 $thisChunkSize = $j; 403 404 # If we couldn't actually use any stubs because the pages were too small, do nothing 405 if ( $usedChunk ) { 406 if ( $extdb != "" ) { 407 # Move blob objects to External Storage 408 $stored = $storeObj->store( $extdb, serialize( $chunk ) ); 409 if ( $stored === false ) { 410 $this->error( "Unable to store object" ); 411 412 return false; 413 } 414 # Store External Storage URLs instead of Stub placeholders 415 foreach ( $stubs as $stub ) { 416 if ( $stub === false ) { 417 continue; 418 } 419 # $stored should provide base path to a BLOB 420 $url = $stored . "/" . $stub->getHash(); 421 $dbw->update( 'text', 422 [ /* SET */ 423 'old_text' => $url, 424 'old_flags' => 'external,utf-8', 425 ], [ /* WHERE */ 426 'old_id' => $stub->getReferrer(), 427 ], 428 __METHOD__ 429 ); 430 } 431 } else { 432 # Store the main object locally 433 $dbw->update( 'text', 434 [ /* SET */ 435 'old_text' => serialize( $chunk ), 436 'old_flags' => 'object,utf-8', 437 ], [ /* WHERE */ 438 'old_id' => $primaryOldid 439 ], 440 __METHOD__ 441 ); 442 443 # Store the stub objects 444 for ( $j = 1; $j < $thisChunkSize; $j++ ) { 445 # Skip if not compressing and don't overwrite the first revision 446 if ( $stubs[$j] !== false && $revs[$i + $j]->old_id != $primaryOldid ) { 447 $dbw->update( 'text', 448 [ /* SET */ 449 'old_text' => serialize( $stubs[$j] ), 450 'old_flags' => 'object,utf-8', 451 ], [ /* WHERE */ 452 'old_id' => $revs[$i + $j]->old_id 453 ], 454 __METHOD__ 455 ); 456 } 457 } 458 } 459 } 460 # Done, next 461 $this->output( "/" ); 462 $this->commitTransaction( $dbw, __METHOD__ ); 463 $i += $thisChunkSize; 464 } 465 $this->output( "\n" ); 466 } 467 468 return true; 469 } 470} 471 472$maintClass = CompressOld::class; 473require_once RUN_MAINTENANCE_IF_MAIN; 474