MediaWiki  REL1_31
compressOld.php
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1 <?php
44 require_once __DIR__ . '/../Maintenance.php';
45 
51 class CompressOld extends Maintenance {
55  const LS_INDIVIDUAL = 0;
56 
60  const LS_CHUNKED = 1;
61 
62  public function __construct() {
63  parent::__construct();
64  $this->addDescription( 'Compress the text of a wiki' );
65  $this->addOption( 'type', 'Set compression type to either: gzip|concat', false, true, 't' );
66  $this->addOption(
67  'chunksize',
68  'Maximum number of revisions in a concat chunk',
69  false,
70  true,
71  'c'
72  );
73  $this->addOption(
74  'begin-date',
75  'Earliest date to check for uncompressed revisions',
76  false,
77  true,
78  'b'
79  );
80  $this->addOption( 'end-date', 'Latest revision date to compress', false, true, 'e' );
81  $this->addOption(
82  'startid',
83  'The id to start from (gzip -> text table, concat -> page table)',
84  false,
85  true,
86  's'
87  );
88  $this->addOption(
89  'extdb',
90  'Store specified revisions in an external cluster (untested)',
91  false,
92  true
93  );
94  $this->addOption(
95  'endid',
96  'The page_id to stop at (only when using concat compression type)',
97  false,
98  true,
99  'n'
100  );
101  }
102 
103  public function execute() {
105  if ( !function_exists( "gzdeflate" ) ) {
106  $this->fatalError( "You must enable zlib support in PHP to compress old revisions!\n" .
107  "Please see http://www.php.net/manual/en/ref.zlib.php\n" );
108  }
109 
110  $type = $this->getOption( 'type', 'concat' );
111  $chunkSize = $this->getOption( 'chunksize', 20 );
112  $startId = $this->getOption( 'startid', 0 );
113  $beginDate = $this->getOption( 'begin-date', '' );
114  $endDate = $this->getOption( 'end-date', '' );
115  $extDB = $this->getOption( 'extdb', '' );
116  $endId = $this->getOption( 'endid', false );
117 
118  if ( $type != 'concat' && $type != 'gzip' ) {
119  $this->error( "Type \"{$type}\" not supported" );
120  }
121 
122  if ( $extDB != '' ) {
123  $this->output( "Compressing database {$wgDBname} to external cluster {$extDB}\n"
124  . str_repeat( '-', 76 ) . "\n\n" );
125  } else {
126  $this->output( "Compressing database {$wgDBname}\n"
127  . str_repeat( '-', 76 ) . "\n\n" );
128  }
129 
130  $success = true;
131  if ( $type == 'concat' ) {
132  $success = $this->compressWithConcat( $startId, $chunkSize, $beginDate,
133  $endDate, $extDB, $endId );
134  } else {
135  $this->compressOldPages( $startId, $extDB );
136  }
137 
138  if ( $success ) {
139  $this->output( "Done.\n" );
140  }
141  }
142 
149  private function compressOldPages( $start = 0, $extdb = '' ) {
150  $chunksize = 50;
151  $this->output( "Starting from old_id $start...\n" );
152  $dbw = $this->getDB( DB_MASTER );
153  do {
154  $res = $dbw->select(
155  'text',
156  [ 'old_id', 'old_flags', 'old_text' ],
157  "old_id>=$start",
158  __METHOD__,
159  [ 'ORDER BY' => 'old_id', 'LIMIT' => $chunksize, 'FOR UPDATE' ]
160  );
161 
162  if ( $res->numRows() == 0 ) {
163  break;
164  }
165 
166  $last = $start;
167 
168  foreach ( $res as $row ) {
169  # print " {$row->old_id} - {$row->old_namespace}:{$row->old_title}\n";
170  $this->compressPage( $row, $extdb );
171  $last = $row->old_id;
172  }
173 
174  $start = $last + 1; # Deletion may leave long empty stretches
175  $this->output( "$start...\n" );
176  } while ( true );
177  }
178 
186  private function compressPage( $row, $extdb ) {
187  if ( false !== strpos( $row->old_flags, 'gzip' )
188  || false !== strpos( $row->old_flags, 'object' )
189  ) {
190  # print "Already compressed row {$row->old_id}\n";
191  return false;
192  }
193  $dbw = $this->getDB( DB_MASTER );
194  $flags = $row->old_flags ? "{$row->old_flags},gzip" : "gzip";
195  $compress = gzdeflate( $row->old_text );
196 
197  # Store in external storage if required
198  if ( $extdb !== '' ) {
199  $storeObj = new ExternalStoreDB;
200  $compress = $storeObj->store( $extdb, $compress );
201  if ( $compress === false ) {
202  $this->error( "Unable to store object" );
203 
204  return false;
205  }
206  }
207 
208  # Update text row
209  $dbw->update( 'text',
210  [ /* SET */
211  'old_flags' => $flags,
212  'old_text' => $compress
213  ], [ /* WHERE */
214  'old_id' => $row->old_id
215  ], __METHOD__,
216  [ 'LIMIT' => 1 ]
217  );
218 
219  return true;
220  }
221 
233  private function compressWithConcat( $startId, $maxChunkSize, $beginDate,
234  $endDate, $extdb = "", $maxPageId = false
235  ) {
236  $loadStyle = self::LS_CHUNKED;
237 
238  $dbr = $this->getDB( DB_REPLICA );
239  $dbw = $this->getDB( DB_MASTER );
240 
241  # Set up external storage
242  if ( $extdb != '' ) {
243  $storeObj = new ExternalStoreDB;
244  }
245 
246  # Get all articles by page_id
247  if ( !$maxPageId ) {
248  $maxPageId = $dbr->selectField( 'page', 'max(page_id)', '', __METHOD__ );
249  }
250  $this->output( "Starting from $startId of $maxPageId\n" );
251  $pageConds = [];
252 
253  /*
254  if ( $exclude_ns0 ) {
255  print "Excluding main namespace\n";
256  $pageConds[] = 'page_namespace<>0';
257  }
258  if ( $queryExtra ) {
259  $pageConds[] = $queryExtra;
260  }
261  */
262 
263  # For each article, get a list of revisions which fit the criteria
264 
265  # No recompression, use a condition on old_flags
266  # Don't compress object type entities, because that might produce data loss when
267  # overwriting bulk storage concat rows. Don't compress external references, because
268  # the script doesn't yet delete rows from external storage.
269  $conds = [
270  'old_flags NOT ' . $dbr->buildLike( $dbr->anyString(), 'object', $dbr->anyString() )
271  . ' AND old_flags NOT '
272  . $dbr->buildLike( $dbr->anyString(), 'external', $dbr->anyString() )
273  ];
274 
275  if ( $beginDate ) {
276  if ( !preg_match( '/^\d{14}$/', $beginDate ) ) {
277  $this->error( "Invalid begin date \"$beginDate\"\n" );
278 
279  return false;
280  }
281  $conds[] = "rev_timestamp>'" . $beginDate . "'";
282  }
283  if ( $endDate ) {
284  if ( !preg_match( '/^\d{14}$/', $endDate ) ) {
285  $this->error( "Invalid end date \"$endDate\"\n" );
286 
287  return false;
288  }
289  $conds[] = "rev_timestamp<'" . $endDate . "'";
290  }
291  if ( $loadStyle == self::LS_CHUNKED ) {
292  $tables = [ 'revision', 'text' ];
293  $fields = [ 'rev_id', 'rev_text_id', 'old_flags', 'old_text' ];
294  $conds[] = 'rev_text_id=old_id';
295  $revLoadOptions = 'FOR UPDATE';
296  } else {
297  $tables = [ 'revision' ];
298  $fields = [ 'rev_id', 'rev_text_id' ];
299  $revLoadOptions = [];
300  }
301 
302  # Don't work with current revisions
303  # Don't lock the page table for update either -- TS 2006-04-04
304  # $tables[] = 'page';
305  # $conds[] = 'page_id=rev_page AND rev_id != page_latest';
306 
307  for ( $pageId = $startId; $pageId <= $maxPageId; $pageId++ ) {
308  wfWaitForSlaves();
309 
310  # Wake up
311  $dbr->ping();
312 
313  # Get the page row
314  $pageRes = $dbr->select( 'page',
315  [ 'page_id', 'page_namespace', 'page_title', 'page_latest' ],
316  $pageConds + [ 'page_id' => $pageId ], __METHOD__ );
317  if ( $pageRes->numRows() == 0 ) {
318  continue;
319  }
320  $pageRow = $dbr->fetchObject( $pageRes );
321 
322  # Display progress
323  $titleObj = Title::makeTitle( $pageRow->page_namespace, $pageRow->page_title );
324  $this->output( "$pageId\t" . $titleObj->getPrefixedDBkey() . " " );
325 
326  # Load revisions
327  $revRes = $dbw->select( $tables, $fields,
328  array_merge( [
329  'rev_page' => $pageRow->page_id,
330  # Don't operate on the current revision
331  # Use < instead of <> in case the current revision has changed
332  # since the page select, which wasn't locking
333  'rev_id < ' . $pageRow->page_latest
334  ], $conds ),
335  __METHOD__,
336  $revLoadOptions
337  );
338  $revs = [];
339  foreach ( $revRes as $revRow ) {
340  $revs[] = $revRow;
341  }
342 
343  if ( count( $revs ) < 2 ) {
344  # No revisions matching, no further processing
345  $this->output( "\n" );
346  continue;
347  }
348 
349  # For each chunk
350  $i = 0;
351  while ( $i < count( $revs ) ) {
352  if ( $i < count( $revs ) - $maxChunkSize ) {
353  $thisChunkSize = $maxChunkSize;
354  } else {
355  $thisChunkSize = count( $revs ) - $i;
356  }
357 
358  $chunk = new ConcatenatedGzipHistoryBlob();
359  $stubs = [];
360  $this->beginTransaction( $dbw, __METHOD__ );
361  $usedChunk = false;
362  $primaryOldid = $revs[$i]->rev_text_id;
363 
364  # Get the text of each revision and add it to the object
365  // phpcs:ignore Generic.CodeAnalysis.ForLoopWithTestFunctionCall
366  for ( $j = 0; $j < $thisChunkSize && $chunk->isHappy(); $j++ ) {
367  $oldid = $revs[$i + $j]->rev_text_id;
368 
369  # Get text
370  if ( $loadStyle == self::LS_INDIVIDUAL ) {
371  $textRow = $dbw->selectRow( 'text',
372  [ 'old_flags', 'old_text' ],
373  [ 'old_id' => $oldid ],
374  __METHOD__,
375  'FOR UPDATE'
376  );
377  $text = Revision::getRevisionText( $textRow );
378  } else {
379  $text = Revision::getRevisionText( $revs[$i + $j] );
380  }
381 
382  if ( $text === false ) {
383  $this->error( "\nError, unable to get text in old_id $oldid" );
384  # $dbw->delete( 'old', [ 'old_id' => $oldid ] );
385  }
386 
387  if ( $extdb == "" && $j == 0 ) {
388  $chunk->setText( $text );
389  $this->output( '.' );
390  } else {
391  # Don't make a stub if it's going to be longer than the article
392  # Stubs are typically about 100 bytes
393  if ( strlen( $text ) < 120 ) {
394  $stub = false;
395  $this->output( 'x' );
396  } else {
397  $stub = new HistoryBlobStub( $chunk->addItem( $text ) );
398  $stub->setLocation( $primaryOldid );
399  $stub->setReferrer( $oldid );
400  $this->output( '.' );
401  $usedChunk = true;
402  }
403  $stubs[$j] = $stub;
404  }
405  }
406  $thisChunkSize = $j;
407 
408  # If we couldn't actually use any stubs because the pages were too small, do nothing
409  if ( $usedChunk ) {
410  if ( $extdb != "" ) {
411  # Move blob objects to External Storage
412  $stored = $storeObj->store( $extdb, serialize( $chunk ) );
413  if ( $stored === false ) {
414  $this->error( "Unable to store object" );
415 
416  return false;
417  }
418  # Store External Storage URLs instead of Stub placeholders
419  foreach ( $stubs as $stub ) {
420  if ( $stub === false ) {
421  continue;
422  }
423  # $stored should provide base path to a BLOB
424  $url = $stored . "/" . $stub->getHash();
425  $dbw->update( 'text',
426  [ /* SET */
427  'old_text' => $url,
428  'old_flags' => 'external,utf-8',
429  ], [ /* WHERE */
430  'old_id' => $stub->getReferrer(),
431  ]
432  );
433  }
434  } else {
435  # Store the main object locally
436  $dbw->update( 'text',
437  [ /* SET */
438  'old_text' => serialize( $chunk ),
439  'old_flags' => 'object,utf-8',
440  ], [ /* WHERE */
441  'old_id' => $primaryOldid
442  ]
443  );
444 
445  # Store the stub objects
446  for ( $j = 1; $j < $thisChunkSize; $j++ ) {
447  # Skip if not compressing and don't overwrite the first revision
448  if ( $stubs[$j] !== false && $revs[$i + $j]->rev_text_id != $primaryOldid ) {
449  $dbw->update( 'text',
450  [ /* SET */
451  'old_text' => serialize( $stubs[$j] ),
452  'old_flags' => 'object,utf-8',
453  ], [ /* WHERE */
454  'old_id' => $revs[$i + $j]->rev_text_id
455  ]
456  );
457  }
458  }
459  }
460  }
461  # Done, next
462  $this->output( "/" );
463  $this->commitTransaction( $dbw, __METHOD__ );
464  $i += $thisChunkSize;
465  }
466  $this->output( "\n" );
467  }
468 
469  return true;
470  }
471 }
472 
474 require_once RUN_MAINTENANCE_IF_MAIN;
ExternalStoreDB
DB accessible external objects.
Definition: ExternalStoreDB.php:38
ExternalStoreDB\store
store( $location, $data)
Insert a data item into a given location.
Definition: ExternalStoreDB.php:95
CompressOld\LS_INDIVIDUAL
const LS_INDIVIDUAL
Option to load each revision individually.
Definition: compressOld.php:55
HistoryBlobStub
Pointer object for an item within a CGZ blob stored in the text table.
Definition: HistoryBlob.php:187
CompressOld\compressWithConcat
compressWithConcat( $startId, $maxChunkSize, $beginDate, $endDate, $extdb="", $maxPageId=false)
Compress the text in chunks after concatenating the revisions.
Definition: compressOld.php:233
Maintenance\fatalError
fatalError( $msg, $exitCode=1)
Output a message and terminate the current script.
Definition: Maintenance.php:439
$last
$last
Definition: profileinfo.php:408
Maintenance\addDescription
addDescription( $text)
Set the description text.
Definition: Maintenance.php:291
ConcatenatedGzipHistoryBlob
Concatenated gzip (CGZ) storage Improves compression ratio by concatenating like objects before gzipp...
Definition: HistoryBlob.php:73
RUN_MAINTENANCE_IF_MAIN
require_once RUN_MAINTENANCE_IF_MAIN
Definition: maintenance.txt:50
CompressOld\__construct
__construct()
Default constructor.
Definition: compressOld.php:62
serialize
serialize()
Definition: ApiMessage.php:184
Revision\getRevisionText
static getRevisionText( $row, $prefix='old_', $wiki=false)
Get revision text associated with an old or archive row.
Definition: Revision.php:1055
$maintClass
$maintClass
Definition: compressOld.php:473
$res
$res
Definition: database.txt:21
Maintenance
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
Definition: maintenance.txt:39
$success
$success
Definition: NoLocalSettings.php:42
wfWaitForSlaves
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
Definition: GlobalFunctions.php:2966
CompressOld\execute
execute()
Do the actual work.
Definition: compressOld.php:103
php
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
$dbr
$dbr
Definition: testCompression.php:50
Maintenance\beginTransaction
beginTransaction(IDatabase $dbw, $fname)
Begin a transcation on a DB.
Definition: Maintenance.php:1336
$wgDBname
controlled by $wgMainCacheType controlled by $wgParserCacheType controlled by $wgMessageCacheType If you set CACHE_NONE to one of the three control default value for MediaWiki still create a but requests to it are no ops and we always fall through to the database If the cache daemon can t be it should also disable itself fairly smoothly By $wgMemc is used but when it is $parserMemc or $messageMemc this is mentioned $wgDBname
Definition: memcached.txt:138
CompressOld\compressOldPages
compressOldPages( $start=0, $extdb='')
Fetch the text row-by-row to 'compressPage' function for compression.
Definition: compressOld.php:149
Maintenance\addOption
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.
Definition: Maintenance.php:219
CompressOld\compressPage
compressPage( $row, $extdb)
Compress the text in gzip format.
Definition: compressOld.php:186
Title\makeTitle
static makeTitle( $ns, $title, $fragment='', $interwiki='')
Create a new Title from a namespace index and a DB key.
Definition: Title.php:534
global
when a variable name is used in a it is silently declared as a new masking the global
Definition: design.txt:95
DB_REPLICA
const DB_REPLICA
Definition: defines.php:25
DB_MASTER
const DB_MASTER
Definition: defines.php:26
Maintenance\commitTransaction
commitTransaction(IDatabase $dbw, $fname)
Commit the transcation on a DB handle and wait for replica DBs to catch up.
Definition: Maintenance.php:1351
CompressOld
Maintenance script that compress the text of a wiki.
Definition: compressOld.php:51
Maintenance\getOption
getOption( $name, $default=null)
Get an option, or return the default.
Definition: Maintenance.php:254
$tables
this hook is for auditing only RecentChangesLinked and Watchlist RecentChangesLinked and Watchlist Do not use this to implement individual filters if they are compatible with the ChangesListFilter and ChangesListFilterGroup structure use sub classes of those in conjunction with the ChangesListSpecialPageStructuredFilters hook This hook can be used to implement filters that do not implement that or custom behavior that is not an individual filter e g Watchlist & $tables
Definition: hooks.txt:1015
as
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
Definition: distributors.txt:22
Maintenance\getDB
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
Definition: Maintenance.php:1309
Maintenance\error
error( $err, $die=0)
Throw an error to the user.
Definition: Maintenance.php:416
Maintenance\output
output( $out, $channel=null)
Throw some output to the user.
Definition: Maintenance.php:388
class
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:56
CompressOld\LS_CHUNKED
const LS_CHUNKED
Option to load revisions in chunks.
Definition: compressOld.php:60
$type
$type
Definition: testCompression.php:48