MediaWiki  REL1_31
SqlBagOStuff.php
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1 <?php
32 use Wikimedia\WaitConditionLoop;
33 
39 class SqlBagOStuff extends BagOStuff {
41  protected $serverInfos;
43  protected $serverTags;
45  protected $numServers;
47  protected $lastExpireAll = 0;
49  protected $purgePeriod = 100;
51  protected $shards = 1;
53  protected $tableName = 'objectcache';
55  protected $replicaOnly = false;
57  protected $syncTimeout = 3;
58 
60  protected $separateMainLB;
62  protected $conns;
64  protected $connFailureTimes = [];
66  protected $connFailureErrors = [];
67 
104  public function __construct( $params ) {
105  parent::__construct( $params );
106 
109 
110  if ( isset( $params['servers'] ) ) {
111  $this->serverInfos = [];
112  $this->serverTags = [];
113  $this->numServers = count( $params['servers'] );
114  $index = 0;
115  foreach ( $params['servers'] as $tag => $info ) {
116  $this->serverInfos[$index] = $info;
117  if ( is_string( $tag ) ) {
118  $this->serverTags[$index] = $tag;
119  } else {
120  $this->serverTags[$index] = isset( $info['host'] ) ? $info['host'] : "#$index";
121  }
122  ++$index;
123  }
124  } elseif ( isset( $params['server'] ) ) {
125  $this->serverInfos = [ $params['server'] ];
126  $this->numServers = count( $this->serverInfos );
127  } else {
128  // Default to using the main wiki's database servers
129  $this->serverInfos = false;
130  $this->numServers = 1;
132  }
133  if ( isset( $params['purgePeriod'] ) ) {
134  $this->purgePeriod = intval( $params['purgePeriod'] );
135  }
136  if ( isset( $params['tableName'] ) ) {
137  $this->tableName = $params['tableName'];
138  }
139  if ( isset( $params['shards'] ) ) {
140  $this->shards = intval( $params['shards'] );
141  }
142  if ( isset( $params['syncTimeout'] ) ) {
143  $this->syncTimeout = $params['syncTimeout'];
144  }
145  $this->replicaOnly = !empty( $params['slaveOnly'] );
146  }
147 
155  protected function getDB( $serverIndex ) {
156  if ( !isset( $this->conns[$serverIndex] ) ) {
157  if ( $serverIndex >= $this->numServers ) {
158  throw new MWException( __METHOD__ . ": Invalid server index \"$serverIndex\"" );
159  }
160 
161  # Don't keep timing out trying to connect for each call if the DB is down
162  if ( isset( $this->connFailureErrors[$serverIndex] )
163  && ( time() - $this->connFailureTimes[$serverIndex] ) < 60
164  ) {
165  throw $this->connFailureErrors[$serverIndex];
166  }
167 
168  if ( $this->serverInfos ) {
169  // Use custom database defined by server connection info
170  $info = $this->serverInfos[$serverIndex];
171  $type = isset( $info['type'] ) ? $info['type'] : 'mysql';
172  $host = isset( $info['host'] ) ? $info['host'] : '[unknown]';
173  $this->logger->debug( __CLASS__ . ": connecting to $host" );
174  // Use a blank trx profiler to ignore expections as this is a cache
175  $info['trxProfiler'] = new TransactionProfiler();
176  $db = Database::factory( $type, $info );
177  $db->clearFlag( DBO_TRX ); // auto-commit mode
178  } else {
179  // Use the main LB database
180  $lb = MediaWikiServices::getInstance()->getDBLoadBalancer();
181  $index = $this->replicaOnly ? DB_REPLICA : DB_MASTER;
182  if ( $lb->getServerType( $lb->getWriterIndex() ) !== 'sqlite' ) {
183  // Keep a separate connection to avoid contention and deadlocks
184  $db = $lb->getConnection( $index, [], false, $lb::CONN_TRX_AUTOCOMMIT );
185  // @TODO: Use a blank trx profiler to ignore expections as this is a cache
186  } else {
187  // However, SQLite has the opposite behavior due to DB-level locking.
188  // Stock sqlite MediaWiki installs use a separate sqlite cache DB instead.
189  $db = $lb->getConnection( $index );
190  }
191  }
192 
193  $this->logger->debug( sprintf( "Connection %s will be used for SqlBagOStuff", $db ) );
194  $this->conns[$serverIndex] = $db;
195  }
196 
197  return $this->conns[$serverIndex];
198  }
199 
205  protected function getTableByKey( $key ) {
206  if ( $this->shards > 1 ) {
207  $hash = hexdec( substr( md5( $key ), 0, 8 ) ) & 0x7fffffff;
208  $tableIndex = $hash % $this->shards;
209  } else {
210  $tableIndex = 0;
211  }
212  if ( $this->numServers > 1 ) {
213  $sortedServers = $this->serverTags;
214  ArrayUtils::consistentHashSort( $sortedServers, $key );
215  reset( $sortedServers );
216  $serverIndex = key( $sortedServers );
217  } else {
218  $serverIndex = 0;
219  }
220  return [ $serverIndex, $this->getTableNameByShard( $tableIndex ) ];
221  }
222 
228  protected function getTableNameByShard( $index ) {
229  if ( $this->shards > 1 ) {
230  $decimals = strlen( $this->shards - 1 );
231  return $this->tableName .
232  sprintf( "%0{$decimals}d", $index );
233  } else {
234  return $this->tableName;
235  }
236  }
237 
238  protected function doGet( $key, $flags = 0 ) {
239  $casToken = null;
240 
241  return $this->getWithToken( $key, $casToken, $flags );
242  }
243 
244  protected function getWithToken( $key, &$casToken, $flags = 0 ) {
245  $values = $this->getMulti( [ $key ] );
246  if ( array_key_exists( $key, $values ) ) {
247  $casToken = $values[$key];
248  return $values[$key];
249  }
250  return false;
251  }
252 
253  public function getMulti( array $keys, $flags = 0 ) {
254  $values = []; // array of (key => value)
255 
256  $keysByTable = [];
257  foreach ( $keys as $key ) {
258  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
259  $keysByTable[$serverIndex][$tableName][] = $key;
260  }
261 
262  $this->garbageCollect(); // expire old entries if any
263 
264  $dataRows = [];
265  foreach ( $keysByTable as $serverIndex => $serverKeys ) {
266  try {
267  $db = $this->getDB( $serverIndex );
268  foreach ( $serverKeys as $tableName => $tableKeys ) {
269  $res = $db->select( $tableName,
270  [ 'keyname', 'value', 'exptime' ],
271  [ 'keyname' => $tableKeys ],
272  __METHOD__,
273  // Approximate write-on-the-fly BagOStuff API via blocking.
274  // This approximation fails if a ROLLBACK happens (which is rare).
275  // We do not want to flush the TRX as that can break callers.
276  $db->trxLevel() ? [ 'LOCK IN SHARE MODE' ] : []
277  );
278  if ( $res === false ) {
279  continue;
280  }
281  foreach ( $res as $row ) {
282  $row->serverIndex = $serverIndex;
283  $row->tableName = $tableName;
284  $dataRows[$row->keyname] = $row;
285  }
286  }
287  } catch ( DBError $e ) {
288  $this->handleReadError( $e, $serverIndex );
289  }
290  }
291 
292  foreach ( $keys as $key ) {
293  if ( isset( $dataRows[$key] ) ) { // HIT?
294  $row = $dataRows[$key];
295  $this->debug( "get: retrieved data; expiry time is " . $row->exptime );
296  $db = null;
297  try {
298  $db = $this->getDB( $row->serverIndex );
299  if ( $this->isExpired( $db, $row->exptime ) ) { // MISS
300  $this->debug( "get: key has expired" );
301  } else { // HIT
302  $values[$key] = $this->unserialize( $db->decodeBlob( $row->value ) );
303  }
304  } catch ( DBQueryError $e ) {
305  $this->handleWriteError( $e, $db, $row->serverIndex );
306  }
307  } else { // MISS
308  $this->debug( 'get: no matching rows' );
309  }
310  }
311 
312  return $values;
313  }
314 
315  public function setMulti( array $data, $expiry = 0 ) {
316  $keysByTable = [];
317  foreach ( $data as $key => $value ) {
318  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
319  $keysByTable[$serverIndex][$tableName][] = $key;
320  }
321 
322  $this->garbageCollect(); // expire old entries if any
323 
324  $result = true;
325  $exptime = (int)$expiry;
326  foreach ( $keysByTable as $serverIndex => $serverKeys ) {
327  $db = null;
328  try {
329  $db = $this->getDB( $serverIndex );
330  } catch ( DBError $e ) {
331  $this->handleWriteError( $e, $db, $serverIndex );
332  $result = false;
333  continue;
334  }
335 
336  if ( $exptime < 0 ) {
337  $exptime = 0;
338  }
339 
340  if ( $exptime == 0 ) {
341  $encExpiry = $this->getMaxDateTime( $db );
342  } else {
343  $exptime = $this->convertExpiry( $exptime );
344  $encExpiry = $db->timestamp( $exptime );
345  }
346  foreach ( $serverKeys as $tableName => $tableKeys ) {
347  $rows = [];
348  foreach ( $tableKeys as $key ) {
349  $rows[] = [
350  'keyname' => $key,
351  'value' => $db->encodeBlob( $this->serialize( $data[$key] ) ),
352  'exptime' => $encExpiry,
353  ];
354  }
355 
356  try {
357  $db->replace(
358  $tableName,
359  [ 'keyname' ],
360  $rows,
361  __METHOD__
362  );
363  } catch ( DBError $e ) {
364  $this->handleWriteError( $e, $db, $serverIndex );
365  $result = false;
366  }
367 
368  }
369 
370  }
371 
372  return $result;
373  }
374 
375  public function set( $key, $value, $exptime = 0, $flags = 0 ) {
376  $ok = $this->setMulti( [ $key => $value ], $exptime );
377  if ( ( $flags & self::WRITE_SYNC ) == self::WRITE_SYNC ) {
378  $ok = $this->waitForReplication() && $ok;
379  }
380 
381  return $ok;
382  }
383 
384  protected function cas( $casToken, $key, $value, $exptime = 0 ) {
385  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
386  $db = null;
387  try {
388  $db = $this->getDB( $serverIndex );
389  $exptime = intval( $exptime );
390 
391  if ( $exptime < 0 ) {
392  $exptime = 0;
393  }
394 
395  if ( $exptime == 0 ) {
396  $encExpiry = $this->getMaxDateTime( $db );
397  } else {
398  $exptime = $this->convertExpiry( $exptime );
399  $encExpiry = $db->timestamp( $exptime );
400  }
401  // (T26425) use a replace if the db supports it instead of
402  // delete/insert to avoid clashes with conflicting keynames
403  $db->update(
404  $tableName,
405  [
406  'keyname' => $key,
407  'value' => $db->encodeBlob( $this->serialize( $value ) ),
408  'exptime' => $encExpiry
409  ],
410  [
411  'keyname' => $key,
412  'value' => $db->encodeBlob( $this->serialize( $casToken ) )
413  ],
414  __METHOD__
415  );
416  } catch ( DBQueryError $e ) {
417  $this->handleWriteError( $e, $db, $serverIndex );
418 
419  return false;
420  }
421 
422  return (bool)$db->affectedRows();
423  }
424 
425  public function delete( $key ) {
426  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
427  $db = null;
428  try {
429  $db = $this->getDB( $serverIndex );
430  $db->delete(
431  $tableName,
432  [ 'keyname' => $key ],
433  __METHOD__ );
434  } catch ( DBError $e ) {
435  $this->handleWriteError( $e, $db, $serverIndex );
436  return false;
437  }
438 
439  return true;
440  }
441 
442  public function incr( $key, $step = 1 ) {
443  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
444  $db = null;
445  try {
446  $db = $this->getDB( $serverIndex );
447  $step = intval( $step );
448  $row = $db->selectRow(
449  $tableName,
450  [ 'value', 'exptime' ],
451  [ 'keyname' => $key ],
452  __METHOD__,
453  [ 'FOR UPDATE' ] );
454  if ( $row === false ) {
455  // Missing
456 
457  return null;
458  }
459  $db->delete( $tableName, [ 'keyname' => $key ], __METHOD__ );
460  if ( $this->isExpired( $db, $row->exptime ) ) {
461  // Expired, do not reinsert
462 
463  return null;
464  }
465 
466  $oldValue = intval( $this->unserialize( $db->decodeBlob( $row->value ) ) );
467  $newValue = $oldValue + $step;
468  $db->insert( $tableName,
469  [
470  'keyname' => $key,
471  'value' => $db->encodeBlob( $this->serialize( $newValue ) ),
472  'exptime' => $row->exptime
473  ], __METHOD__, 'IGNORE' );
474 
475  if ( $db->affectedRows() == 0 ) {
476  // Race condition. See T30611
477  $newValue = null;
478  }
479  } catch ( DBError $e ) {
480  $this->handleWriteError( $e, $db, $serverIndex );
481  return null;
482  }
483 
484  return $newValue;
485  }
486 
487  public function merge( $key, callable $callback, $exptime = 0, $attempts = 10, $flags = 0 ) {
488  $ok = $this->mergeViaCas( $key, $callback, $exptime, $attempts );
489  if ( ( $flags & self::WRITE_SYNC ) == self::WRITE_SYNC ) {
490  $ok = $this->waitForReplication() && $ok;
491  }
492 
493  return $ok;
494  }
495 
496  public function changeTTL( $key, $expiry = 0 ) {
497  list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
498  $db = null;
499  try {
500  $db = $this->getDB( $serverIndex );
501  $db->update(
502  $tableName,
503  [ 'exptime' => $db->timestamp( $this->convertExpiry( $expiry ) ) ],
504  [ 'keyname' => $key, 'exptime > ' . $db->addQuotes( $db->timestamp( time() ) ) ],
505  __METHOD__
506  );
507  if ( $db->affectedRows() == 0 ) {
508  return false;
509  }
510  } catch ( DBError $e ) {
511  $this->handleWriteError( $e, $db, $serverIndex );
512  return false;
513  }
514 
515  return true;
516  }
517 
523  protected function isExpired( $db, $exptime ) {
524  return $exptime != $this->getMaxDateTime( $db ) && wfTimestamp( TS_UNIX, $exptime ) < time();
525  }
526 
531  protected function getMaxDateTime( $db ) {
532  if ( time() > 0x7fffffff ) {
533  return $db->timestamp( 1 << 62 );
534  } else {
535  return $db->timestamp( 0x7fffffff );
536  }
537  }
538 
539  protected function garbageCollect() {
540  if ( !$this->purgePeriod || $this->replicaOnly ) {
541  // Disabled
542  return;
543  }
544  // Only purge on one in every $this->purgePeriod requests.
545  if ( $this->purgePeriod !== 1 && mt_rand( 0, $this->purgePeriod - 1 ) ) {
546  return;
547  }
548  $now = time();
549  // Avoid repeating the delete within a few seconds
550  if ( $now > ( $this->lastExpireAll + 1 ) ) {
551  $this->lastExpireAll = $now;
552  $this->expireAll();
553  }
554  }
555 
556  public function expireAll() {
558  }
559 
566  public function deleteObjectsExpiringBefore( $timestamp, $progressCallback = false ) {
567  for ( $serverIndex = 0; $serverIndex < $this->numServers; $serverIndex++ ) {
568  $db = null;
569  try {
570  $db = $this->getDB( $serverIndex );
571  $dbTimestamp = $db->timestamp( $timestamp );
572  $totalSeconds = false;
573  $baseConds = [ 'exptime < ' . $db->addQuotes( $dbTimestamp ) ];
574  for ( $i = 0; $i < $this->shards; $i++ ) {
575  $maxExpTime = false;
576  while ( true ) {
577  $conds = $baseConds;
578  if ( $maxExpTime !== false ) {
579  $conds[] = 'exptime >= ' . $db->addQuotes( $maxExpTime );
580  }
581  $rows = $db->select(
582  $this->getTableNameByShard( $i ),
583  [ 'keyname', 'exptime' ],
584  $conds,
585  __METHOD__,
586  [ 'LIMIT' => 100, 'ORDER BY' => 'exptime' ] );
587  if ( $rows === false || !$rows->numRows() ) {
588  break;
589  }
590  $keys = [];
591  $row = $rows->current();
592  $minExpTime = $row->exptime;
593  if ( $totalSeconds === false ) {
594  $totalSeconds = wfTimestamp( TS_UNIX, $timestamp )
595  - wfTimestamp( TS_UNIX, $minExpTime );
596  }
597  foreach ( $rows as $row ) {
598  $keys[] = $row->keyname;
599  $maxExpTime = $row->exptime;
600  }
601 
602  $db->delete(
603  $this->getTableNameByShard( $i ),
604  [
605  'exptime >= ' . $db->addQuotes( $minExpTime ),
606  'exptime < ' . $db->addQuotes( $dbTimestamp ),
607  'keyname' => $keys
608  ],
609  __METHOD__ );
610 
611  if ( $progressCallback ) {
612  if ( intval( $totalSeconds ) === 0 ) {
613  $percent = 0;
614  } else {
615  $remainingSeconds = wfTimestamp( TS_UNIX, $timestamp )
616  - wfTimestamp( TS_UNIX, $maxExpTime );
617  if ( $remainingSeconds > $totalSeconds ) {
618  $totalSeconds = $remainingSeconds;
619  }
620  $processedSeconds = $totalSeconds - $remainingSeconds;
621  $percent = ( $i + $processedSeconds / $totalSeconds )
622  / $this->shards * 100;
623  }
624  $percent = ( $percent / $this->numServers )
625  + ( $serverIndex / $this->numServers * 100 );
626  call_user_func( $progressCallback, $percent );
627  }
628  }
629  }
630  } catch ( DBError $e ) {
631  $this->handleWriteError( $e, $db, $serverIndex );
632  return false;
633  }
634  }
635  return true;
636  }
637 
643  public function deleteAll() {
644  for ( $serverIndex = 0; $serverIndex < $this->numServers; $serverIndex++ ) {
645  $db = null;
646  try {
647  $db = $this->getDB( $serverIndex );
648  for ( $i = 0; $i < $this->shards; $i++ ) {
649  $db->delete( $this->getTableNameByShard( $i ), '*', __METHOD__ );
650  }
651  } catch ( DBError $e ) {
652  $this->handleWriteError( $e, $db, $serverIndex );
653  return false;
654  }
655  }
656  return true;
657  }
658 
667  protected function serialize( &$data ) {
668  $serial = serialize( $data );
669 
670  if ( function_exists( 'gzdeflate' ) ) {
671  return gzdeflate( $serial );
672  } else {
673  return $serial;
674  }
675  }
676 
682  protected function unserialize( $serial ) {
683  if ( function_exists( 'gzinflate' ) ) {
684  Wikimedia\suppressWarnings();
685  $decomp = gzinflate( $serial );
686  Wikimedia\restoreWarnings();
687 
688  if ( false !== $decomp ) {
689  $serial = $decomp;
690  }
691  }
692 
693  $ret = unserialize( $serial );
694 
695  return $ret;
696  }
697 
704  protected function handleReadError( DBError $exception, $serverIndex ) {
705  if ( $exception instanceof DBConnectionError ) {
706  $this->markServerDown( $exception, $serverIndex );
707  }
708  $this->logger->error( "DBError: {$exception->getMessage()}" );
709  if ( $exception instanceof DBConnectionError ) {
711  $this->logger->debug( __METHOD__ . ": ignoring connection error" );
712  } else {
714  $this->logger->debug( __METHOD__ . ": ignoring query error" );
715  }
716  }
717 
726  protected function handleWriteError( DBError $exception, IDatabase $db = null, $serverIndex ) {
727  if ( !$db ) {
728  $this->markServerDown( $exception, $serverIndex );
729  } elseif ( $db->wasReadOnlyError() ) {
730  if ( $db->trxLevel() && $this->usesMainDB() ) {
731  // Errors like deadlocks and connection drops already cause rollback.
732  // For consistency, we have no choice but to throw an error and trigger
733  // complete rollback if the main DB is also being used as the cache DB.
734  throw $exception;
735  }
736  }
737 
738  $this->logger->error( "DBError: {$exception->getMessage()}" );
739  if ( $exception instanceof DBConnectionError ) {
741  $this->logger->debug( __METHOD__ . ": ignoring connection error" );
742  } else {
744  $this->logger->debug( __METHOD__ . ": ignoring query error" );
745  }
746  }
747 
754  protected function markServerDown( DBError $exception, $serverIndex ) {
755  unset( $this->conns[$serverIndex] ); // bug T103435
756 
757  if ( isset( $this->connFailureTimes[$serverIndex] ) ) {
758  if ( time() - $this->connFailureTimes[$serverIndex] >= 60 ) {
759  unset( $this->connFailureTimes[$serverIndex] );
760  unset( $this->connFailureErrors[$serverIndex] );
761  } else {
762  $this->logger->debug( __METHOD__ . ": Server #$serverIndex already down" );
763  return;
764  }
765  }
766  $now = time();
767  $this->logger->info( __METHOD__ . ": Server #$serverIndex down until " . ( $now + 60 ) );
768  $this->connFailureTimes[$serverIndex] = $now;
769  $this->connFailureErrors[$serverIndex] = $exception;
770  }
771 
775  public function createTables() {
776  for ( $serverIndex = 0; $serverIndex < $this->numServers; $serverIndex++ ) {
777  $db = $this->getDB( $serverIndex );
778  if ( $db->getType() !== 'mysql' ) {
779  throw new MWException( __METHOD__ . ' is not supported on this DB server' );
780  }
781 
782  for ( $i = 0; $i < $this->shards; $i++ ) {
783  $db->query(
784  'CREATE TABLE ' . $db->tableName( $this->getTableNameByShard( $i ) ) .
785  ' LIKE ' . $db->tableName( 'objectcache' ),
786  __METHOD__ );
787  }
788  }
789  }
790 
794  protected function usesMainDB() {
795  return !$this->serverInfos;
796  }
797 
798  protected function waitForReplication() {
799  if ( !$this->usesMainDB() ) {
800  // Custom DB server list; probably doesn't use replication
801  return true;
802  }
803 
804  $lb = MediaWikiServices::getInstance()->getDBLoadBalancer();
805  if ( $lb->getServerCount() <= 1 ) {
806  return true; // no replica DBs
807  }
808 
809  // Main LB is used; wait for any replica DBs to catch up
810  $masterPos = $lb->getMasterPos();
811  if ( !$masterPos ) {
812  return true; // not applicable
813  }
814 
815  $loop = new WaitConditionLoop(
816  function () use ( $lb, $masterPos ) {
817  return $lb->waitForAll( $masterPos, 1 );
818  },
821  );
822 
823  return ( $loop->invoke() === $loop::CONDITION_REACHED );
824  }
825 }
SqlBagOStuff\__construct
__construct( $params)
Constructor.
Definition: SqlBagOStuff.php:104
SqlBagOStuff\createTables
createTables()
Create shard tables.
Definition: SqlBagOStuff.php:775
Wikimedia\Rdbms\Database
Relational database abstraction object.
Definition: Database.php:48
SqlBagOStuff\doGet
doGet( $key, $flags=0)
Definition: SqlBagOStuff.php:238
ArrayUtils\consistentHashSort
static consistentHashSort(&$array, $key, $separator="\000")
Sort the given array in a pseudo-random order which depends only on the given key and each element va...
Definition: ArrayUtils.php:49
SqlBagOStuff\merge
merge( $key, callable $callback, $exptime=0, $attempts=10, $flags=0)
Merge changes into the existing cache value (possibly creating a new one)
Definition: SqlBagOStuff.php:487
use
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
Definition: APACHE-LICENSE-2.0.txt:10
BagOStuff\ERR_UNREACHABLE
const ERR_UNREACHABLE
Definition: BagOStuff.php:82
$rows
do that in ParserLimitReportFormat instead use this to modify the parameters of the image all existing parser cache entries will be invalid To avoid you ll need to handle that somehow(e.g. with the RejectParserCacheValue hook) because MediaWiki won 't do it for you. & $defaults also a ContextSource after deleting those rows but within the same transaction $rows
Definition: hooks.txt:2783
SqlBagOStuff\changeTTL
changeTTL( $key, $expiry=0)
Reset the TTL on a key if it exists.
Definition: SqlBagOStuff.php:496
SqlBagOStuff\$lastExpireAll
int $lastExpireAll
Definition: SqlBagOStuff.php:47
array
the array() calling protocol came about after MediaWiki 1.4rc1.
SqlBagOStuff\serialize
serialize(&$data)
Serialize an object and, if possible, compress the representation.
Definition: SqlBagOStuff.php:667
SqlBagOStuff\$separateMainLB
LoadBalancer null $separateMainLB
Definition: SqlBagOStuff.php:60
SqlBagOStuff\$serverInfos
array[] $serverInfos
(server index => server config)
Definition: SqlBagOStuff.php:41
SqlBagOStuff\$conns
array $conns
Definition: SqlBagOStuff.php:62
IExpiringStore\QOS_EMULATION_SQL
const QOS_EMULATION_SQL
Definition: IExpiringStore.php:50
wfTimestamp
wfTimestamp( $outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
Definition: GlobalFunctions.php:1980
$ret
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 & $ret
Definition: hooks.txt:2005
SqlBagOStuff\incr
incr( $key, $step=1)
Increase stored value of $key by $value while preserving its TTL.
Definition: SqlBagOStuff.php:442
BagOStuff\convertExpiry
convertExpiry( $exptime)
Convert an optionally relative time to an absolute time.
Definition: BagOStuff.php:695
BagOStuff\debug
debug( $text)
Definition: BagOStuff.php:682
$params
$params
Definition: styleTest.css.php:40
BagOStuff
interface is intended to be more or less compatible with the PHP memcached client.
Definition: BagOStuff.php:47
$res
$res
Definition: database.txt:21
$result
The index of the header message $result[1]=The index of the body text message $result[2 through n]=Parameters passed to body text message. Please note the header message cannot receive/use parameters. 'ImgAuthModifyHeaders':Executed just before a file is streamed to a user via img_auth.php, allowing headers to be modified beforehand. $title:LinkTarget object & $headers:HTTP headers(name=> value, names are case insensitive). Two headers get special handling:If-Modified-Since(value must be a valid HTTP date) and Range(must be of the form "bytes=(\d*-\d*)") will be honored when streaming the file. 'ImportHandleLogItemXMLTag':When parsing a XML tag in a log item. Return false to stop further processing of the tag $reader:XMLReader object $logInfo:Array of information 'ImportHandlePageXMLTag':When parsing a XML tag in a page. Return false to stop further processing of the tag $reader:XMLReader object & $pageInfo:Array of information 'ImportHandleRevisionXMLTag':When parsing a XML tag in a page revision. Return false to stop further processing of the tag $reader:XMLReader object $pageInfo:Array of page information $revisionInfo:Array of revision information 'ImportHandleToplevelXMLTag':When parsing a top level XML tag. Return false to stop further processing of the tag $reader:XMLReader object 'ImportHandleUnknownUser':When a user doesn 't exist locally, this hook is called to give extensions an opportunity to auto-create it. If the auto-creation is successful, return false. $name:User name 'ImportHandleUploadXMLTag':When parsing a XML tag in a file upload. Return false to stop further processing of the tag $reader:XMLReader object $revisionInfo:Array of information 'ImportLogInterwikiLink':Hook to change the interwiki link used in log entries and edit summaries for transwiki imports. & $fullInterwikiPrefix:Interwiki prefix, may contain colons. & $pageTitle:String that contains page title. 'ImportSources':Called when reading from the $wgImportSources configuration variable. Can be used to lazy-load the import sources list. & $importSources:The value of $wgImportSources. Modify as necessary. See the comment in DefaultSettings.php for the detail of how to structure this array. 'InfoAction':When building information to display on the action=info page. $context:IContextSource object & $pageInfo:Array of information 'InitializeArticleMaybeRedirect':MediaWiki check to see if title is a redirect. & $title:Title object for the current page & $request:WebRequest & $ignoreRedirect:boolean to skip redirect check & $target:Title/string of redirect target & $article:Article object 'InternalParseBeforeLinks':during Parser 's internalParse method before links but after nowiki/noinclude/includeonly/onlyinclude and other processings. & $parser:Parser object & $text:string containing partially parsed text & $stripState:Parser 's internal StripState object 'InternalParseBeforeSanitize':during Parser 's internalParse method just before the parser removes unwanted/dangerous HTML tags and after nowiki/noinclude/includeonly/onlyinclude and other processings. Ideal for syntax-extensions after template/parser function execution which respect nowiki and HTML-comments. & $parser:Parser object & $text:string containing partially parsed text & $stripState:Parser 's internal StripState object 'InterwikiLoadPrefix':When resolving if a given prefix is an interwiki or not. Return true without providing an interwiki to continue interwiki search. $prefix:interwiki prefix we are looking for. & $iwData:output array describing the interwiki with keys iw_url, iw_local, iw_trans and optionally iw_api and iw_wikiid. 'InvalidateEmailComplete':Called after a user 's email has been invalidated successfully. $user:user(object) whose email is being invalidated 'IRCLineURL':When constructing the URL to use in an IRC notification. Callee may modify $url and $query, URL will be constructed as $url . $query & $url:URL to index.php & $query:Query string $rc:RecentChange object that triggered url generation 'IsFileCacheable':Override the result of Article::isFileCacheable()(if true) & $article:article(object) being checked 'IsTrustedProxy':Override the result of IP::isTrustedProxy() & $ip:IP being check & $result:Change this value to override the result of IP::isTrustedProxy() 'IsUploadAllowedFromUrl':Override the result of UploadFromUrl::isAllowedUrl() $url:URL used to upload from & $allowed:Boolean indicating if uploading is allowed for given URL 'isValidEmailAddr':Override the result of Sanitizer::validateEmail(), for instance to return false if the domain name doesn 't match your organization. $addr:The e-mail address entered by the user & $result:Set this and return false to override the internal checks 'isValidPassword':Override the result of User::isValidPassword() $password:The password entered by the user & $result:Set this and return false to override the internal checks $user:User the password is being validated for 'Language::getMessagesFileName':$code:The language code or the language we 're looking for a messages file for & $file:The messages file path, you can override this to change the location. 'LanguageGetMagic':DEPRECATED! Use $magicWords in a file listed in $wgExtensionMessagesFiles instead. Use this to define synonyms of magic words depending of the language & $magicExtensions:associative array of magic words synonyms $lang:language code(string) 'LanguageGetNamespaces':Provide custom ordering for namespaces or remove namespaces. Do not use this hook to add namespaces. Use CanonicalNamespaces for that. & $namespaces:Array of namespaces indexed by their numbers 'LanguageGetSpecialPageAliases':DEPRECATED! Use $specialPageAliases in a file listed in $wgExtensionMessagesFiles instead. Use to define aliases of special pages names depending of the language & $specialPageAliases:associative array of magic words synonyms $lang:language code(string) 'LanguageGetTranslatedLanguageNames':Provide translated language names. & $names:array of language code=> language name $code:language of the preferred translations 'LanguageLinks':Manipulate a page 's language links. This is called in various places to allow extensions to define the effective language links for a page. $title:The page 's Title. & $links:Array with elements of the form "language:title" in the order that they will be output. & $linkFlags:Associative array mapping prefixed links to arrays of flags. Currently unused, but planned to provide support for marking individual language links in the UI, e.g. for featured articles. 'LanguageSelector':Hook to change the language selector available on a page. $out:The output page. $cssClassName:CSS class name of the language selector. 'LinkBegin':DEPRECATED! Use HtmlPageLinkRendererBegin instead. Used when generating internal and interwiki links in Linker::link(), before processing starts. Return false to skip default processing and return $ret. See documentation for Linker::link() for details on the expected meanings of parameters. $skin:the Skin object $target:the Title that the link is pointing to & $html:the contents that the< a > tag should have(raw HTML) $result
Definition: hooks.txt:1993
SqlBagOStuff\handleWriteError
handleWriteError(DBError $exception, IDatabase $db=null, $serverIndex)
Handle a DBQueryError which occurred during a write operation.
Definition: SqlBagOStuff.php:726
Wikimedia\Rdbms\DBError
Database error base class.
Definition: DBError.php:30
DBO_TRX
const DBO_TRX
Definition: defines.php:12
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
Wikimedia\Rdbms\IDatabase
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:38
IExpiringStore\ATTR_EMULATION
const ATTR_EMULATION
Definition: IExpiringStore.php:49
SqlBagOStuff\getTableByKey
getTableByKey( $key)
Get the server index and table name for a given key.
Definition: SqlBagOStuff.php:205
key
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 but I prefer the flexibility This should also do the output encoding The system allocates a global one in $wgOut Title Represents the title of an and does all the work of translating among various forms such as plain database key
Definition: design.txt:26
SqlBagOStuff\$syncTimeout
int $syncTimeout
Definition: SqlBagOStuff.php:57
SqlBagOStuff\expireAll
expireAll()
Definition: SqlBagOStuff.php:556
MWException
MediaWiki exception.
Definition: MWException.php:26
SqlBagOStuff\deleteAll
deleteAll()
Delete content of shard tables in every server.
Definition: SqlBagOStuff.php:643
SqlBagOStuff\getDB
getDB( $serverIndex)
Get a connection to the specified database.
Definition: SqlBagOStuff.php:155
tableName
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 tableName() and addQuotes(). You will need both of them. ------------------------------------------------------------------------ Basic query optimisation ------------------------------------------------------------------------ MediaWiki developers who need to write DB queries should have some understanding of databases and the performance issues associated with them. Patches containing unacceptably slow features will not be accepted. Unindexed queries are generally not welcome in MediaWiki
SqlBagOStuff\$connFailureErrors
array $connFailureErrors
Exceptions.
Definition: SqlBagOStuff.php:66
SqlBagOStuff\getMulti
getMulti(array $keys, $flags=0)
Get an associative array containing the item for each of the keys that have items.
Definition: SqlBagOStuff.php:253
SqlBagOStuff\handleReadError
handleReadError(DBError $exception, $serverIndex)
Handle a DBError which occurred during a read operation.
Definition: SqlBagOStuff.php:704
IExpiringStore\QOS_SYNCWRITES_BE
const QOS_SYNCWRITES_BE
Definition: IExpiringStore.php:54
SqlBagOStuff\cas
cas( $casToken, $key, $value, $exptime=0)
Check and set an item.
Definition: SqlBagOStuff.php:384
SqlBagOStuff\isExpired
isExpired( $db, $exptime)
Definition: SqlBagOStuff.php:523
SqlBagOStuff\$tableName
string $tableName
Definition: SqlBagOStuff.php:53
BagOStuff\$busyCallbacks
callable[] $busyCallbacks
Definition: BagOStuff.php:71
DB_REPLICA
const DB_REPLICA
Definition: defines.php:25
wfTimestampNow
wfTimestampNow()
Convenience function; returns MediaWiki timestamp for the present time.
Definition: GlobalFunctions.php:2009
DB_MASTER
const DB_MASTER
Definition: defines.php:26
list
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
Wikimedia\Rdbms\DBQueryError
Definition: DBQueryError.php:27
Wikimedia\Rdbms\LoadBalancer
Database connection, tracking, load balancing, and transaction manager for a cluster.
Definition: LoadBalancer.php:41
SqlBagOStuff\waitForReplication
waitForReplication()
Definition: SqlBagOStuff.php:798
SqlBagOStuff\garbageCollect
garbageCollect()
Definition: SqlBagOStuff.php:539
$value
$value
Definition: styleTest.css.php:45
SqlBagOStuff\unserialize
unserialize( $serial)
Unserialize and, if necessary, decompress an object.
Definition: SqlBagOStuff.php:682
SqlBagOStuff\deleteObjectsExpiringBefore
deleteObjectsExpiringBefore( $timestamp, $progressCallback=false)
Delete objects from the database which expire before a certain date.
Definition: SqlBagOStuff.php:566
SqlBagOStuff\$connFailureTimes
array $connFailureTimes
UNIX timestamps.
Definition: SqlBagOStuff.php:64
IExpiringStore\ATTR_SYNCWRITES
const ATTR_SYNCWRITES
Definition: IExpiringStore.php:52
SqlBagOStuff\$numServers
int $numServers
Definition: SqlBagOStuff.php:45
BagOStuff\mergeViaCas
mergeViaCas( $key, $callback, $exptime=0, $attempts=10)
Definition: BagOStuff.php:292
SqlBagOStuff
Class to store objects in the database.
Definition: SqlBagOStuff.php:39
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
SqlBagOStuff\getMaxDateTime
getMaxDateTime( $db)
Definition: SqlBagOStuff.php:531
Wikimedia\Rdbms\DBConnectionError
Definition: DBConnectionError.php:26
$keys
$keys
Definition: testCompression.php:67
SqlBagOStuff\setMulti
setMulti(array $data, $expiry=0)
Batch insertion.
Definition: SqlBagOStuff.php:315
SqlBagOStuff\getWithToken
getWithToken( $key, &$casToken, $flags=0)
Definition: SqlBagOStuff.php:244
SqlBagOStuff\$serverTags
string[] $serverTags
(server index => tag/host name)
Definition: SqlBagOStuff.php:43
MediaWikiServices
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 MediaWikiServices
Definition: injection.txt:25
SqlBagOStuff\$replicaOnly
bool $replicaOnly
Definition: SqlBagOStuff.php:55
Wikimedia\Rdbms\TransactionProfiler
Helper class that detects high-contention DB queries via profiling calls.
Definition: TransactionProfiler.php:38
IExpiringStore\QOS_SYNCWRITES_NONE
const QOS_SYNCWRITES_NONE
Definition: IExpiringStore.php:53
SqlBagOStuff\markServerDown
markServerDown(DBError $exception, $serverIndex)
Mark a server down due to a DBConnectionError exception.
Definition: SqlBagOStuff.php:754
BagOStuff\setLastError
setLastError( $err)
Set the "last error" registry.
Definition: BagOStuff.php:633
SqlBagOStuff\$purgePeriod
int $purgePeriod
Definition: SqlBagOStuff.php:49
BagOStuff\ERR_UNEXPECTED
const ERR_UNEXPECTED
Definition: BagOStuff.php:83
SqlBagOStuff\usesMainDB
usesMainDB()
Definition: SqlBagOStuff.php:794
SqlBagOStuff\$shards
int $shards
Definition: SqlBagOStuff.php:51
$e
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException' returning false will NOT prevent logging $e
Definition: hooks.txt:2171
SqlBagOStuff\getTableNameByShard
getTableNameByShard( $index)
Get the table name for a given shard index.
Definition: SqlBagOStuff.php:228
$type
$type
Definition: testCompression.php:48