MediaWiki REL1_27
dumpTextPass.php
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1<?php
27require_once __DIR__ . '/backup.inc';
28require_once __DIR__ . '/../includes/export/WikiExporter.php';
29
34 public $prefetch = null;
35
36 // when we spend more than maxTimeAllowed seconds on this run, we continue
37 // processing until we write out the next complete page, then save output file(s),
38 // rename it/them and open new one(s)
39 public $maxTimeAllowed = 0; // 0 = no limit
40
41 protected $input = "php://stdin";
43 protected $fetchCount = 0;
44 protected $prefetchCount = 0;
45 protected $prefetchCountLast = 0;
46 protected $fetchCountLast = 0;
47
48 protected $maxFailures = 5;
50 protected $failureTimeout = 5; // Seconds to sleep after db failure
51
52 protected $bufferSize = 524288; // In bytes. Maximum size to read from the stub in on go.
53
54 protected $php = "php";
55 protected $spawn = false;
56
60 protected $spawnProc = false;
61
65 protected $spawnWrite = false;
66
70 protected $spawnRead = false;
71
75 protected $spawnErr = false;
76
77 protected $xmlwriterobj = false;
78
79 protected $timeExceeded = false;
80 protected $firstPageWritten = false;
81 protected $lastPageWritten = false;
82 protected $checkpointJustWritten = false;
83 protected $checkpointFiles = [];
84
88 protected $db;
89
93 function __construct( $args = null ) {
94 parent::__construct();
95
96 $this->addDescription( <<<TEXT
97This script postprocesses XML dumps from dumpBackup.php to add
98page text which was stubbed out (using --stub).
99
100XML input is accepted on stdin.
101XML output is sent to stdout; progress reports are sent to stderr.
102TEXT
103 );
104 $this->stderr = fopen( "php://stderr", "wt" );
105
106 $this->addOption( 'stub', 'To load a compressed stub dump instead of stdin. ' .
107 'Specify as --stub=<type>:<file>.', false, true );
108 $this->addOption( 'prefetch', 'Use a prior dump file as a text source, to savepressure on the ' .
109 'database. (Requires the XMLReader extension). Specify as --prefetch=<type>:<file>',
110 false, true );
111 $this->addOption( 'maxtime', 'Write out checkpoint file after this many minutes (writing' .
112 'out complete page, closing xml file properly, and opening new one' .
113 'with header). This option requires the checkpointfile option.', false, true );
114 $this->addOption( 'checkpointfile', 'Use this string for checkpoint filenames,substituting ' .
115 'first pageid written for the first %s (required) and the last pageid written for the ' .
116 'second %s if it exists.', false, true, false, true ); // This can be specified multiple times
117 $this->addOption( 'quiet', 'Don\'t dump status reports to stderr.' );
118 $this->addOption( 'current', 'Base ETA on number of pages in database instead of all revisions' );
119 $this->addOption( 'spawn', 'Spawn a subprocess for loading text records' );
120 $this->addOption( 'buffersize', 'Buffer size in bytes to use for reading the stub. ' .
121 '(Default: 512KB, Minimum: 4KB)', false, true );
122
123 if ( $args ) {
124 $this->loadWithArgv( $args );
125 $this->processOptions();
126 }
127 }
128
129 function execute() {
130 $this->processOptions();
131 $this->dump( true );
132 }
133
134 function processOptions() {
135 global $IP;
136
137 parent::processOptions();
138
139 if ( $this->hasOption( 'buffersize' ) ) {
140 $this->bufferSize = max( intval( $this->getOption( 'buffersize' ) ), 4 * 1024 );
141 }
142
143 if ( $this->hasOption( 'prefetch' ) ) {
144 require_once "$IP/maintenance/backupPrefetch.inc";
145 $url = $this->processFileOpt( $this->getOption( 'prefetch' ) );
146 $this->prefetch = new BaseDump( $url );
147 }
148
149 if ( $this->hasOption( 'stub' ) ) {
150 $this->input = $this->processFileOpt( $this->getOption( 'stub' ) );
151 }
152
153 if ( $this->hasOption( 'maxtime' ) ) {
154 $this->maxTimeAllowed = intval( $this->getOption( 'maxtime' ) ) * 60;
155 }
156
157 if ( $this->hasOption( 'checkpointfile' ) ) {
158 $this->checkpointFiles = $this->getOption( 'checkpointfile' );
159 }
160
161 if ( $this->hasOption( 'current' ) ) {
163 }
164
165 if ( $this->hasOption( 'full' ) ) {
167 }
168
169 if ( $this->hasOption( 'spawn' ) ) {
170 $this->spawn = true;
171 $val = $this->getOption( 'spawn' );
172 if ( $val !== 1 ) {
173 $this->php = $val;
174 }
175 }
176 }
177
189 function rotateDb() {
190 // Cleaning up old connections
191 if ( isset( $this->lb ) ) {
192 $this->lb->closeAll();
193 unset( $this->lb );
194 }
195
196 if ( $this->forcedDb !== null ) {
197 $this->db = $this->forcedDb;
198
199 return;
200 }
201
202 if ( isset( $this->db ) && $this->db->isOpen() ) {
203 throw new MWException( 'DB is set and has not been closed by the Load Balancer' );
204 }
205
206 unset( $this->db );
207
208 // Trying to set up new connection.
209 // We do /not/ retry upon failure, but delegate to encapsulating logic, to avoid
210 // individually retrying at different layers of code.
211
212 // 1. The LoadBalancer.
213 try {
214 $this->lb = wfGetLBFactory()->newMainLB();
215 } catch ( Exception $e ) {
216 throw new MWException( __METHOD__
217 . " rotating DB failed to obtain new load balancer (" . $e->getMessage() . ")" );
218 }
219
220 // 2. The Connection, through the load balancer.
221 try {
222 $this->db = $this->lb->getConnection( DB_SLAVE, 'dump' );
223 } catch ( Exception $e ) {
224 throw new MWException( __METHOD__
225 . " rotating DB failed to obtain new database (" . $e->getMessage() . ")" );
226 }
227 }
228
230 parent::initProgress();
231 $this->timeOfCheckpoint = $this->startTime;
232 }
233
234 function dump( $history, $text = WikiExporter::TEXT ) {
235 // Notice messages will foul up your XML output even if they're
236 // relatively harmless.
237 if ( ini_get( 'display_errors' ) ) {
238 ini_set( 'display_errors', 'stderr' );
239 }
240
241 $this->initProgress( $this->history );
242
243 // We are trying to get an initial database connection to avoid that the
244 // first try of this request's first call to getText fails. However, if
245 // obtaining a good DB connection fails it's not a serious issue, as
246 // getText does retry upon failure and can start without having a working
247 // DB connection.
248 try {
249 $this->rotateDb();
250 } catch ( Exception $e ) {
251 // We do not even count this as failure. Just let eventual
252 // watchdogs know.
253 $this->progress( "Getting initial DB connection failed (" .
254 $e->getMessage() . ")" );
255 }
256
257 $this->egress = new ExportProgressFilter( $this->sink, $this );
258
259 // it would be nice to do it in the constructor, oh well. need egress set
260 $this->finalOptionCheck();
261
262 // we only want this so we know how to close a stream :-P
263 $this->xmlwriterobj = new XmlDumpWriter();
264
265 $input = fopen( $this->input, "rt" );
266 $this->readDump( $input );
267
268 if ( $this->spawnProc ) {
269 $this->closeSpawn();
270 }
271
272 $this->report( true );
273 }
274
275 function processFileOpt( $opt ) {
276 $split = explode( ':', $opt, 2 );
277 $val = $split[0];
278 $param = '';
279 if ( count( $split ) === 2 ) {
280 $param = $split[1];
281 }
282 $fileURIs = explode( ';', $param );
283 foreach ( $fileURIs as $URI ) {
284 switch ( $val ) {
285 case "file":
286 $newURI = $URI;
287 break;
288 case "gzip":
289 $newURI = "compress.zlib://$URI";
290 break;
291 case "bzip2":
292 $newURI = "compress.bzip2://$URI";
293 break;
294 case "7zip":
295 $newURI = "mediawiki.compress.7z://$URI";
296 break;
297 default:
298 $newURI = $URI;
299 }
300 $newFileURIs[] = $newURI;
301 }
302 $val = implode( ';', $newFileURIs );
303
304 return $val;
305 }
306
310 function showReport() {
311 if ( !$this->prefetch ) {
312 parent::showReport();
313
314 return;
315 }
316
317 if ( $this->reporting ) {
318 $now = wfTimestamp( TS_DB );
319 $nowts = microtime( true );
320 $deltaAll = $nowts - $this->startTime;
321 $deltaPart = $nowts - $this->lastTime;
322 $this->pageCountPart = $this->pageCount - $this->pageCountLast;
323 $this->revCountPart = $this->revCount - $this->revCountLast;
324
325 if ( $deltaAll ) {
326 $portion = $this->revCount / $this->maxCount;
327 $eta = $this->startTime + $deltaAll / $portion;
328 $etats = wfTimestamp( TS_DB, intval( $eta ) );
329 if ( $this->fetchCount ) {
330 $fetchRate = 100.0 * $this->prefetchCount / $this->fetchCount;
331 } else {
332 $fetchRate = '-';
333 }
334 $pageRate = $this->pageCount / $deltaAll;
335 $revRate = $this->revCount / $deltaAll;
336 } else {
337 $pageRate = '-';
338 $revRate = '-';
339 $etats = '-';
340 $fetchRate = '-';
341 }
342 if ( $deltaPart ) {
343 if ( $this->fetchCountLast ) {
344 $fetchRatePart = 100.0 * $this->prefetchCountLast / $this->fetchCountLast;
345 } else {
346 $fetchRatePart = '-';
347 }
348 $pageRatePart = $this->pageCountPart / $deltaPart;
349 $revRatePart = $this->revCountPart / $deltaPart;
350 } else {
351 $fetchRatePart = '-';
352 $pageRatePart = '-';
353 $revRatePart = '-';
354 }
355 $this->progress( sprintf(
356 "%s: %s (ID %d) %d pages (%0.1f|%0.1f/sec all|curr), "
357 . "%d revs (%0.1f|%0.1f/sec all|curr), %0.1f%%|%0.1f%% "
358 . "prefetched (all|curr), ETA %s [max %d]",
359 $now, wfWikiID(), $this->ID, $this->pageCount, $pageRate,
360 $pageRatePart, $this->revCount, $revRate, $revRatePart,
361 $fetchRate, $fetchRatePart, $etats, $this->maxCount
362 ) );
363 $this->lastTime = $nowts;
364 $this->revCountLast = $this->revCount;
365 $this->prefetchCountLast = $this->prefetchCount;
366 $this->fetchCountLast = $this->fetchCount;
367 }
368 }
369
370 function setTimeExceeded() {
371 $this->timeExceeded = true;
372 }
373
375 if ( $this->maxTimeAllowed
376 && ( $this->lastTime - $this->timeOfCheckpoint > $this->maxTimeAllowed )
377 ) {
378 return true;
379 }
380
381 return false;
382 }
383
384 function finalOptionCheck() {
385 if ( ( $this->checkpointFiles && !$this->maxTimeAllowed )
386 || ( $this->maxTimeAllowed && !$this->checkpointFiles )
387 ) {
388 throw new MWException( "Options checkpointfile and maxtime must be specified together.\n" );
389 }
390 foreach ( $this->checkpointFiles as $checkpointFile ) {
391 $count = substr_count( $checkpointFile, "%s" );
392 if ( $count != 2 ) {
393 throw new MWException( "Option checkpointfile must contain two '%s' "
394 . "for substitution of first and last pageids, count is $count instead, "
395 . "file is $checkpointFile.\n" );
396 }
397 }
398
399 if ( $this->checkpointFiles ) {
400 $filenameList = (array)$this->egress->getFilenames();
401 if ( count( $filenameList ) != count( $this->checkpointFiles ) ) {
402 throw new MWException( "One checkpointfile must be specified "
403 . "for each output option, if maxtime is used.\n" );
404 }
405 }
406 }
407
413 function readDump( $input ) {
414 $this->buffer = "";
415 $this->openElement = false;
416 $this->atStart = true;
417 $this->state = "";
418 $this->lastName = "";
419 $this->thisPage = 0;
420 $this->thisRev = 0;
421 $this->thisRevModel = null;
422 $this->thisRevFormat = null;
423
424 $parser = xml_parser_create( "UTF-8" );
425 xml_parser_set_option( $parser, XML_OPTION_CASE_FOLDING, false );
426
427 xml_set_element_handler(
428 $parser,
429 [ $this, 'startElement' ],
430 [ $this, 'endElement' ]
431 );
432 xml_set_character_data_handler( $parser, [ $this, 'characterData' ] );
433
434 $offset = 0; // for context extraction on error reporting
435 do {
436 if ( $this->checkIfTimeExceeded() ) {
437 $this->setTimeExceeded();
438 }
439 $chunk = fread( $input, $this->bufferSize );
440 if ( !xml_parse( $parser, $chunk, feof( $input ) ) ) {
441 wfDebug( "TextDumpPass::readDump encountered XML parsing error\n" );
442
443 $byte = xml_get_current_byte_index( $parser );
444 $msg = wfMessage( 'xml-error-string',
445 'XML import parse failure',
446 xml_get_current_line_number( $parser ),
447 xml_get_current_column_number( $parser ),
448 $byte . ( is_null( $chunk ) ? null : ( '; "' . substr( $chunk, $byte - $offset, 16 ) . '"' ) ),
449 xml_error_string( xml_get_error_code( $parser ) ) )->escaped();
450
451 xml_parser_free( $parser );
452
453 throw new MWException( $msg );
454 }
455 $offset += strlen( $chunk );
456 } while ( $chunk !== false && !feof( $input ) );
457 if ( $this->maxTimeAllowed ) {
458 $filenameList = (array)$this->egress->getFilenames();
459 // we wrote some stuff after last checkpoint that needs renamed
460 if ( file_exists( $filenameList[0] ) ) {
461 $newFilenames = [];
462 # we might have just written the header and footer and had no
463 # pages or revisions written... perhaps they were all deleted
464 # there's no pageID 0 so we use that. the caller is responsible
465 # for deciding what to do with a file containing only the
466 # siteinfo information and the mw tags.
467 if ( !$this->firstPageWritten ) {
468 $firstPageID = str_pad( 0, 9, "0", STR_PAD_LEFT );
469 $lastPageID = str_pad( 0, 9, "0", STR_PAD_LEFT );
470 } else {
471 $firstPageID = str_pad( $this->firstPageWritten, 9, "0", STR_PAD_LEFT );
472 $lastPageID = str_pad( $this->lastPageWritten, 9, "0", STR_PAD_LEFT );
473 }
474
475 $filenameCount = count( $filenameList );
476 for ( $i = 0; $i < $filenameCount; $i++ ) {
477 $checkpointNameFilledIn = sprintf( $this->checkpointFiles[$i], $firstPageID, $lastPageID );
478 $fileinfo = pathinfo( $filenameList[$i] );
479 $newFilenames[] = $fileinfo['dirname'] . '/' . $checkpointNameFilledIn;
480 }
481 $this->egress->closeAndRename( $newFilenames );
482 }
483 }
484 xml_parser_free( $parser );
485
486 return true;
487 }
488
498 private function exportTransform( $text, $model, $format = null ) {
499 try {
501 $text = $handler->exportTransform( $text, $format );
502 }
503 catch ( MWException $ex ) {
504 $this->progress(
505 "Unable to apply export transformation for content model '$model': " .
506 $ex->getMessage()
507 );
508 }
509
510 return $text;
511 }
512
533 function getText( $id, $model = null, $format = null ) {
535
536 $prefetchNotTried = true; // Whether or not we already tried to get the text via prefetch.
537 $text = false; // The candidate for a good text. false if no proper value.
538 $failures = 0; // The number of times, this invocation of getText already failed.
539
540 // The number of times getText failed without yielding a good text in between.
541 static $consecutiveFailedTextRetrievals = 0;
542
543 $this->fetchCount++;
544
545 // To allow to simply return on success and do not have to worry about book keeping,
546 // we assume, this fetch works (possible after some retries). Nevertheless, we koop
547 // the old value, so we can restore it, if problems occur (See after the while loop).
548 $oldConsecutiveFailedTextRetrievals = $consecutiveFailedTextRetrievals;
549 $consecutiveFailedTextRetrievals = 0;
550
551 if ( $model === null && $wgContentHandlerUseDB ) {
552 $row = $this->db->selectRow(
553 'revision',
554 [ 'rev_content_model', 'rev_content_format' ],
555 [ 'rev_id' => $this->thisRev ],
556 __METHOD__
557 );
558
559 if ( $row ) {
560 $model = $row->rev_content_model;
561 $format = $row->rev_content_format;
562 }
563 }
564
565 if ( $model === null || $model === '' ) {
566 $model = false;
567 }
568
569 while ( $failures < $this->maxFailures ) {
570
571 // As soon as we found a good text for the $id, we will return immediately.
572 // Hence, if we make it past the try catch block, we know that we did not
573 // find a good text.
574
575 try {
576 // Step 1: Get some text (or reuse from previous iteratuon if checking
577 // for plausibility failed)
578
579 // Trying to get prefetch, if it has not been tried before
580 if ( $text === false && isset( $this->prefetch ) && $prefetchNotTried ) {
581 $prefetchNotTried = false;
582 $tryIsPrefetch = true;
583 $text = $this->prefetch->prefetch( intval( $this->thisPage ),
584 intval( $this->thisRev ) );
585
586 if ( $text === null ) {
587 $text = false;
588 }
589
590 if ( is_string( $text ) && $model !== false ) {
591 // Apply export transformation to text coming from an old dump.
592 // The purpose of this transformation is to convert up from legacy
593 // formats, which may still be used in the older dump that is used
594 // for pre-fetching. Applying the transformation again should not
595 // interfere with content that is already in the correct form.
596 $text = $this->exportTransform( $text, $model, $format );
597 }
598 }
599
600 if ( $text === false ) {
601 // Fallback to asking the database
602 $tryIsPrefetch = false;
603 if ( $this->spawn ) {
604 $text = $this->getTextSpawned( $id );
605 } else {
606 $text = $this->getTextDb( $id );
607 }
608
609 if ( $text !== false && $model !== false ) {
610 // Apply export transformation to text coming from the database.
611 // Prefetched text should already have transformations applied.
612 $text = $this->exportTransform( $text, $model, $format );
613 }
614
615 // No more checks for texts from DB for now.
616 // If we received something that is not false,
617 // We treat it as good text, regardless of whether it actually is or is not
618 if ( $text !== false ) {
619 return $text;
620 }
621 }
622
623 if ( $text === false ) {
624 throw new MWException( "Generic error while obtaining text for id " . $id );
625 }
626
627 // We received a good candidate for the text of $id via some method
628
629 // Step 2: Checking for plausibility and return the text if it is
630 // plausible
631 $revID = intval( $this->thisRev );
632 if ( !isset( $this->db ) ) {
633 throw new MWException( "No database available" );
634 }
635
636 if ( $model !== CONTENT_MODEL_WIKITEXT ) {
637 $revLength = strlen( $text );
638 } else {
639 $revLength = $this->db->selectField( 'revision', 'rev_len', [ 'rev_id' => $revID ] );
640 }
641
642 if ( strlen( $text ) == $revLength ) {
643 if ( $tryIsPrefetch ) {
644 $this->prefetchCount++;
645 }
646
647 return $text;
648 }
649
650 $text = false;
651 throw new MWException( "Received text is unplausible for id " . $id );
652 } catch ( Exception $e ) {
653 $msg = "getting/checking text " . $id . " failed (" . $e->getMessage() . ")";
654 if ( $failures + 1 < $this->maxFailures ) {
655 $msg .= " (Will retry " . ( $this->maxFailures - $failures - 1 ) . " more times)";
656 }
657 $this->progress( $msg );
658 }
659
660 // Something went wrong; we did not a text that was plausible :(
661 $failures++;
662
663 // A failure in a prefetch hit does not warrant resetting db connection etc.
664 if ( !$tryIsPrefetch ) {
665 // After backing off for some time, we try to reboot the whole process as
666 // much as possible to not carry over failures from one part to the other
667 // parts
668 sleep( $this->failureTimeout );
669 try {
670 $this->rotateDb();
671 if ( $this->spawn ) {
672 $this->closeSpawn();
673 $this->openSpawn();
674 }
675 } catch ( Exception $e ) {
676 $this->progress( "Rebooting getText infrastructure failed (" . $e->getMessage() . ")" .
677 " Trying to continue anyways" );
678 }
679 }
680 }
681
682 // Retirieving a good text for $id failed (at least) maxFailures times.
683 // We abort for this $id.
684
685 // Restoring the consecutive failures, and maybe aborting, if the dump
686 // is too broken.
687 $consecutiveFailedTextRetrievals = $oldConsecutiveFailedTextRetrievals + 1;
688 if ( $consecutiveFailedTextRetrievals > $this->maxConsecutiveFailedTextRetrievals ) {
689 throw new MWException( "Graceful storage failure" );
690 }
691
692 return "";
693 }
694
701 private function getTextDb( $id ) {
703 if ( !isset( $this->db ) ) {
704 throw new MWException( __METHOD__ . "No database available" );
705 }
706 $row = $this->db->selectRow( 'text',
707 [ 'old_text', 'old_flags' ],
708 [ 'old_id' => $id ],
709 __METHOD__ );
710 $text = Revision::getRevisionText( $row );
711 if ( $text === false ) {
712 return false;
713 }
714 $stripped = str_replace( "\r", "", $text );
715 $normalized = $wgContLang->normalize( $stripped );
716
717 return $normalized;
718 }
719
720 private function getTextSpawned( $id ) {
721 MediaWiki\suppressWarnings();
722 if ( !$this->spawnProc ) {
723 // First time?
724 $this->openSpawn();
725 }
726 $text = $this->getTextSpawnedOnce( $id );
727 MediaWiki\restoreWarnings();
728
729 return $text;
730 }
731
732 function openSpawn() {
733 global $IP;
734
735 if ( file_exists( "$IP/../multiversion/MWScript.php" ) ) {
736 $cmd = implode( " ",
737 array_map( 'wfEscapeShellArg',
738 [
739 $this->php,
740 "$IP/../multiversion/MWScript.php",
741 "fetchText.php",
742 '--wiki', wfWikiID() ] ) );
743 } else {
744 $cmd = implode( " ",
745 array_map( 'wfEscapeShellArg',
746 [
747 $this->php,
748 "$IP/maintenance/fetchText.php",
749 '--wiki', wfWikiID() ] ) );
750 }
751 $spec = [
752 0 => [ "pipe", "r" ],
753 1 => [ "pipe", "w" ],
754 2 => [ "file", "/dev/null", "a" ] ];
755 $pipes = [];
756
757 $this->progress( "Spawning database subprocess: $cmd" );
758 $this->spawnProc = proc_open( $cmd, $spec, $pipes );
759 if ( !$this->spawnProc ) {
760 $this->progress( "Subprocess spawn failed." );
761
762 return false;
763 }
764 list(
765 $this->spawnWrite, // -> stdin
766 $this->spawnRead, // <- stdout
767 ) = $pipes;
768
769 return true;
770 }
771
772 private function closeSpawn() {
773 MediaWiki\suppressWarnings();
774 if ( $this->spawnRead ) {
775 fclose( $this->spawnRead );
776 }
777 $this->spawnRead = false;
778 if ( $this->spawnWrite ) {
779 fclose( $this->spawnWrite );
780 }
781 $this->spawnWrite = false;
782 if ( $this->spawnErr ) {
783 fclose( $this->spawnErr );
784 }
785 $this->spawnErr = false;
786 if ( $this->spawnProc ) {
787 pclose( $this->spawnProc );
788 }
789 $this->spawnProc = false;
790 MediaWiki\restoreWarnings();
791 }
792
793 private function getTextSpawnedOnce( $id ) {
795
796 $ok = fwrite( $this->spawnWrite, "$id\n" );
797 // $this->progress( ">> $id" );
798 if ( !$ok ) {
799 return false;
800 }
801
802 $ok = fflush( $this->spawnWrite );
803 // $this->progress( ">> [flush]" );
804 if ( !$ok ) {
805 return false;
806 }
807
808 // check that the text id they are sending is the one we asked for
809 // this avoids out of sync revision text errors we have encountered in the past
810 $newId = fgets( $this->spawnRead );
811 if ( $newId === false ) {
812 return false;
813 }
814 if ( $id != intval( $newId ) ) {
815 return false;
816 }
817
818 $len = fgets( $this->spawnRead );
819 // $this->progress( "<< " . trim( $len ) );
820 if ( $len === false ) {
821 return false;
822 }
823
824 $nbytes = intval( $len );
825 // actual error, not zero-length text
826 if ( $nbytes < 0 ) {
827 return false;
828 }
829
830 $text = "";
831
832 // Subprocess may not send everything at once, we have to loop.
833 while ( $nbytes > strlen( $text ) ) {
834 $buffer = fread( $this->spawnRead, $nbytes - strlen( $text ) );
835 if ( $buffer === false ) {
836 break;
837 }
838 $text .= $buffer;
839 }
840
841 $gotbytes = strlen( $text );
842 if ( $gotbytes != $nbytes ) {
843 $this->progress( "Expected $nbytes bytes from database subprocess, got $gotbytes " );
844
845 return false;
846 }
847
848 // Do normalization in the dump thread...
849 $stripped = str_replace( "\r", "", $text );
850 $normalized = $wgContLang->normalize( $stripped );
851
852 return $normalized;
853 }
854
855 function startElement( $parser, $name, $attribs ) {
856 $this->checkpointJustWritten = false;
857
858 $this->clearOpenElement( null );
859 $this->lastName = $name;
860
861 if ( $name == 'revision' ) {
862 $this->state = $name;
863 $this->egress->writeOpenPage( null, $this->buffer );
864 $this->buffer = "";
865 } elseif ( $name == 'page' ) {
866 $this->state = $name;
867 if ( $this->atStart ) {
868 $this->egress->writeOpenStream( $this->buffer );
869 $this->buffer = "";
870 $this->atStart = false;
871 }
872 }
873
874 if ( $name == "text" && isset( $attribs['id'] ) ) {
875 $id = $attribs['id'];
876 $model = trim( $this->thisRevModel );
877 $format = trim( $this->thisRevFormat );
878
879 $model = $model === '' ? null : $model;
880 $format = $format === '' ? null : $format;
881
882 $text = $this->getText( $id, $model, $format );
883 $this->openElement = [ $name, [ 'xml:space' => 'preserve' ] ];
884 if ( strlen( $text ) > 0 ) {
885 $this->characterData( $parser, $text );
886 }
887 } else {
888 $this->openElement = [ $name, $attribs ];
889 }
890 }
891
892 function endElement( $parser, $name ) {
893 $this->checkpointJustWritten = false;
894
895 if ( $this->openElement ) {
896 $this->clearOpenElement( "" );
897 } else {
898 $this->buffer .= "</$name>";
899 }
900
901 if ( $name == 'revision' ) {
902 $this->egress->writeRevision( null, $this->buffer );
903 $this->buffer = "";
904 $this->thisRev = "";
905 $this->thisRevModel = null;
906 $this->thisRevFormat = null;
907 } elseif ( $name == 'page' ) {
908 if ( !$this->firstPageWritten ) {
909 $this->firstPageWritten = trim( $this->thisPage );
910 }
911 $this->lastPageWritten = trim( $this->thisPage );
912 if ( $this->timeExceeded ) {
913 $this->egress->writeClosePage( $this->buffer );
914 // nasty hack, we can't just write the chardata after the
915 // page tag, it will include leading blanks from the next line
916 $this->egress->sink->write( "\n" );
917
918 $this->buffer = $this->xmlwriterobj->closeStream();
919 $this->egress->writeCloseStream( $this->buffer );
920
921 $this->buffer = "";
922 $this->thisPage = "";
923 // this could be more than one file if we had more than one output arg
924
925 $filenameList = (array)$this->egress->getFilenames();
926 $newFilenames = [];
927 $firstPageID = str_pad( $this->firstPageWritten, 9, "0", STR_PAD_LEFT );
928 $lastPageID = str_pad( $this->lastPageWritten, 9, "0", STR_PAD_LEFT );
929 $filenamesCount = count( $filenameList );
930 for ( $i = 0; $i < $filenamesCount; $i++ ) {
931 $checkpointNameFilledIn = sprintf( $this->checkpointFiles[$i], $firstPageID, $lastPageID );
932 $fileinfo = pathinfo( $filenameList[$i] );
933 $newFilenames[] = $fileinfo['dirname'] . '/' . $checkpointNameFilledIn;
934 }
935 $this->egress->closeRenameAndReopen( $newFilenames );
936 $this->buffer = $this->xmlwriterobj->openStream();
937 $this->timeExceeded = false;
938 $this->timeOfCheckpoint = $this->lastTime;
939 $this->firstPageWritten = false;
940 $this->checkpointJustWritten = true;
941 } else {
942 $this->egress->writeClosePage( $this->buffer );
943 $this->buffer = "";
944 $this->thisPage = "";
945 }
946 } elseif ( $name == 'mediawiki' ) {
947 $this->egress->writeCloseStream( $this->buffer );
948 $this->buffer = "";
949 }
950 }
951
952 function characterData( $parser, $data ) {
953 $this->clearOpenElement( null );
954 if ( $this->lastName == "id" ) {
955 if ( $this->state == "revision" ) {
956 $this->thisRev .= $data;
957 } elseif ( $this->state == "page" ) {
958 $this->thisPage .= $data;
959 }
960 } elseif ( $this->lastName == "model" ) {
961 $this->thisRevModel .= $data;
962 } elseif ( $this->lastName == "format" ) {
963 $this->thisRevFormat .= $data;
964 }
965
966 // have to skip the newline left over from closepagetag line of
967 // end of checkpoint files. nasty hack!!
968 if ( $this->checkpointJustWritten ) {
969 if ( $data[0] == "\n" ) {
970 $data = substr( $data, 1 );
971 }
972 $this->checkpointJustWritten = false;
973 }
974 $this->buffer .= htmlspecialchars( $data );
975 }
976
977 function clearOpenElement( $style ) {
978 if ( $this->openElement ) {
979 $this->buffer .= Xml::element( $this->openElement[0], $this->openElement[1], $style );
980 $this->openElement = false;
981 }
982 }
983}
984
985$maintClass = 'TextPassDumper';
986require_once RUN_MAINTENANCE_IF_MAIN;
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for and distribution as defined by Sections through of this document Licensor shall mean the copyright owner or entity authorized by the copyright owner that is granting the License Legal Entity shall mean the union of the acting entity and all other entities that control are controlled by or are under common control with that entity For the purposes of this definition control direct or to cause the direction or management of such whether by contract or including but not limited to software source documentation and configuration files Object form shall mean any form resulting from mechanical transformation or translation of a Source including but not limited to compiled object generated and conversions to other media types Work shall mean the work of whether in Source or Object made available under the as indicated by a copyright notice that is included in or attached to the whether in Source or Object that is based or other modifications as a an original work of authorship For the purposes of this Derivative Works shall not include works that remain separable from
$wgContentHandlerUseDB
Set to false to disable use of the database fields introduced by the ContentHandler facility.
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
const TS_DB
MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
wfGetLBFactory()
Get the load balancer factory object.
wfTimestamp( $outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
wfWikiID()
Get an ASCII string identifying this wiki This is used as a prefix in memcached keys.
$i
Definition Parser.php:1694
$buffer
Definition Parser.php:1692
$IP
Definition WebStart.php:58
if( $line===false) $args
Definition cdb.php:64
progress( $string)
Definition backup.inc:413
DatabaseBase null $forcedDb
The dependency-injected database to use.
Definition backup.inc:66
report( $final=false)
Definition backup.inc:368
Readahead helper for making large MediaWiki data dumps; reads in a previous XML dump to sequentially ...
static getForModelID( $modelId)
Returns the ContentHandler singleton for the given model ID.
Database abstraction object.
Definition Database.php:32
MediaWiki exception.
hasOption( $name)
Checks to see if a particular param exists.
addDescription( $text)
Set the description text.
loadWithArgv( $argv)
Load params and arguments from a given array of command-line arguments.
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.
getOption( $name, $default=null)
Get an option, or return the default.
static getRevisionText( $row, $prefix='old_', $wiki=false)
Get revision text associated with an old or archive row $row is usually an object from wfFetchRow(),...
$maxConsecutiveFailedTextRetrievals
showReport()
Overridden to include prefetch ratio if enabled.
bool resource $spawnProc
getTextDb( $id)
May throw a database error if, say, the server dies during query.
endElement( $parser, $name)
clearOpenElement( $style)
bool resource $spawnErr
getText( $id, $model=null, $format=null)
Tries to get the revision text for a revision id.
exportTransform( $text, $model, $format=null)
Applies applicable export transformations to $text.
startElement( $parser, $name, $attribs)
processOptions()
Processes arguments and sets $this->$sink accordingly.
bool resource $spawnRead
characterData( $parser, $data)
initProgress( $history=WikiExporter::FULL)
Initialise starting time and maximum revision count.
execute()
Do the actual work.
__construct( $args=null)
DatabaseBase $db
dump( $history, $text=WikiExporter::TEXT)
bool resource $spawnWrite
rotateDb()
Drop the database connection $this->db and try to get a new one.
static element( $element, $attribs=null, $contents='', $allowShortTag=true)
Format an XML element with given attributes and, optionally, text content.
Definition Xml.php:39
The ContentHandler facility adds support for arbitrary content types on wiki instead of relying on wikitext for everything It was introduced in MediaWiki Each kind of and so on Built in content types are
We use the convention $dbr for read and $dbw for write to help you keep track of whether the database object is a the world will explode Or to be a subsequent write query which succeeded on the master may fail when replicated to the slave due to a unique key collision Replication on the slave will stop and it may take hours to repair the database and get it back online Setting read_only in my cnf on the slave will avoid this but given the dire we prefer to have as many checks as possible We provide a but the wrapper functions like please read the documentation for except in special pages derived from QueryPage It s a common pitfall for new developers to submit code containing SQL queries which examine huge numbers of rows Remember that COUNT * is(N), counting rows in atable is like counting beans in a bucket.------------------------------------------------------------------------ Replication------------------------------------------------------------------------The largest installation of MediaWiki, Wikimedia, uses a large set ofslave MySQL servers replicating writes made to a master MySQL server. Itis important to understand the issues associated with this setup if youwant to write code destined for Wikipedia.It 's often the case that the best algorithm to use for a given taskdepends on whether or not replication is in use. Due to our unabashedWikipedia-centrism, we often just use the replication-friendly version, but if you like, you can use wfGetLB() ->getServerCount() > 1 tocheck to see if replication is in use.===Lag===Lag primarily occurs when large write queries are sent to the master.Writes on the master are executed in parallel, but they are executed inserial when they are replicated to the slaves. The master writes thequery to the binlog when the transaction is committed. The slaves pollthe binlog and start executing the query as soon as it appears. They canservice reads while they are performing a write query, but will not readanything more from the binlog and thus will perform no more writes. Thismeans that if the write query runs for a long time, the slaves will lagbehind the master for the time it takes for the write query to complete.Lag can be exacerbated by high read load. MediaWiki 's load balancer willstop sending reads to a slave when it is lagged by more than 30 seconds.If the load ratios are set incorrectly, or if there is too much loadgenerally, this may lead to a slave permanently hovering around 30seconds lag.If all slaves are lagged by more than 30 seconds, MediaWiki will stopwriting to the database. All edits and other write operations will berefused, with an error returned to the user. This gives the slaves achance to catch up. Before we had this mechanism, the slaves wouldregularly lag by several minutes, making review of recent editsdifficult.In addition to this, MediaWiki attempts to ensure that the user seesevents occurring on the wiki in chronological order. A few seconds of lagcan be tolerated, as long as the user sees a consistent picture fromsubsequent requests. This is done by saving the master binlog positionin the session, and then at the start of each request, waiting for theslave to catch up to that position before doing any reads from it. Ifthis wait times out, reads are allowed anyway, but the request isconsidered to be in "lagged slave mode". Lagged slave mode can bechecked by calling wfGetLB() ->getLaggedSlaveMode(). The onlypractical consequence at present is a warning displayed in the pagefooter.===Lag avoidance===To avoid excessive lag, queries which write large numbers of rows shouldbe split up, generally to write one row at a time. Multi-row INSERT ...SELECT queries are the worst offenders should be avoided altogether.Instead do the select first and then the insert.===Working with lag===Despite our best efforts, it 's not practical to guarantee a low-lagenvironment. Lag will usually be less than one second, but mayoccasionally be up to 30 seconds. For scalability, it 's very importantto keep load on the master low, so simply sending all your queries tothe master is not the answer. So when you have a genuine need forup-to-date data, the following approach is advised:1) Do a quick query to the master for a sequence number or timestamp 2) Run the full query on the slave and check if it matches the data you gotfrom the master 3) If it doesn 't, run the full query on the masterTo avoid swamping the master every time the slaves lag, use of thisapproach should be kept to a minimum. In most cases you should just readfrom the slave and let the user deal with the delay.------------------------------------------------------------------------ Lock contention------------------------------------------------------------------------Due to the high write rate on Wikipedia(and some other wikis), MediaWiki developers need to be very careful to structure their writesto avoid long-lasting locks. By default, MediaWiki opens a transactionat the first query, and commits it before the output is sent. Locks willbe held from the time when the query is done until the commit. So youcan reduce lock time by doing as much processing as possible before youdo your write queries.Often this approach is not good enough, and it becomes necessary toenclose small groups of queries in their own transaction. Use thefollowing syntax:$dbw=wfGetDB(DB_MASTER
deferred txt A few of the database updates required by various functions here can be deferred until after the result page is displayed to the user For updating the view updating the linked to tables after a etc PHP does not yet have any way to tell the server to actually return and disconnect while still running these but it might have such a feature in the future We handle these by creating a deferred update object and putting those objects on a global list
Definition deferred.txt:11
this class mediates it Skin Encapsulates a look and feel for the wiki All of the functions that render HTML and make choices about how to render it are here and are called from various other places when and is meant to be subclassed with other skins that may override some of its functions The User object contains a reference to a and so rather than having a global skin object we just rely on the global User and get the skin with $wgUser and also has some character encoding functions and other locale stuff The current user interface language is instantiated as and the local content language as $wgContLang
Definition design.txt:57
design txt This is a brief overview of the new design More thorough and up to date information is available on the documentation wiki at etc Handles the details of getting and saving to the user table of the and dealing with sessions and cookies OutputPage Encapsulates the entire HTML page that will be sent in response to any server request It is used by calling its functions to add in any and then calling output() to send it all. It could be easily changed to send incrementally if that becomes useful
when a variable name is used in a it is silently declared as a new local masking the global
Definition design.txt:95
design txt This is a brief overview of the new design More thorough and up to date information is available on the documentation wiki at etc Handles the details of getting and saving to the user table of the and dealing with sessions and cookies OutputPage Encapsulates the entire HTML page that will be sent in response to any server request It is used by calling its functions to add text
Definition design.txt:18
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
$maintClass
const CONTENT_MODEL_WIKITEXT
Definition Defines.php:278
const DB_SLAVE
Definition Defines.php:47
the array() calling protocol came about after MediaWiki 1.4rc1.
do that in ParserLimitReportFormat instead $parser
Definition hooks.txt:2341
null means default in associative array with keys and values unescaped Should be merged with default with a value of false meaning to suppress the attribute in associative array with keys and values unescaped noclasses just before the function returns a value If you return an< a > element with HTML attributes $attribs and contents $html will be returned If you return $ret will be returned and may include noclasses after processing & $attribs
Definition hooks.txt:1819
presenting them properly to the user as errors is done by the caller return true use this to change the list i e etc next in line in page history
Definition hooks.txt:1597
null means default in associative array with keys and values unescaped Should be merged with default with a value of false meaning to suppress the attribute in associative array with keys and values unescaped noclasses just before the function returns a value If you return an< a > element with HTML attributes $attribs and contents $html will be returned If you return $ret will be returned and may include noclasses after processing after in associative array form externallinks including delete and has completed for all link tables whether this was an auto creation default is conds Array Extra conditions for the No matching items in log is displayed if loglist is empty msgKey Array If you want a nice box with a set this to the key of the message First element is the message additional optional elements are parameters for the key that are processed with wfMessage() -> params() ->parseAsBlock() - offset Set to overwrite offset parameter in $wgRequest set to '' to unset offset - wrap String Wrap the message in html(usually something like "&lt;div ...>$1&lt;/div>"). - flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException':Called before an exception(or PHP error) is logged. This is meant for integration with external error aggregation services
An extension or a local will often add custom code to the function with or without a global variable For someone wanting email notification when an article is shown may add
Definition hooks.txt:56
do that in ParserLimitReportFormat instead use this to modify the parameters of the image and a DIV can begin in one section and end in another Make sure your code can handle that case gracefully See the EditSectionClearerLink extension for an example zero but section is usually empty its values are the globals values before the output is cached one of or reset my talk page
Definition hooks.txt:2388
We ve cleaned up the code here by removing clumps of infrequently used code and moving them off somewhere else It s much easier for someone working with this code to see what s _really_ going on
Definition hooks.txt:88
Allows to change the fields on the form that will be generated $name
Definition hooks.txt:314
this hook is for auditing only or null if authentication failed before getting that far or null if we can t even determine that probably a stub it is not rendered in wiki pages or galleries in category pages allow injecting custom HTML after the section Any uses of the hook need to handle escaping see BaseTemplate::getToolbox and BaseTemplate::makeListItem for details on the format of individual items inside of this array or by returning and letting standard HTTP rendering take place modifiable or by returning false and taking over the output modifiable modifiable after all normalizations have been except for the $wgMaxImageArea check set to true or false to override the $wgMaxImageArea check result gives extension the possibility to transform it themselves $handler
Definition hooks.txt:885
returning false will NOT prevent logging $e
Definition hooks.txt:1940
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition injection.txt:37
require_once RUN_MAINTENANCE_IF_MAIN