MediaWiki  master
SqlBlobStore.php
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1 <?php
27 namespace MediaWiki\Storage;
28 
29 use AppendIterator;
32 use IDBAccessObject;
33 use IExpiringStore;
34 use InvalidArgumentException;
35 use MWException;
36 use StatusValue;
37 use WANObjectCache;
38 use Wikimedia\Assert\Assert;
39 use Wikimedia\AtEase\AtEase;
42 
52 
53  // Note: the name has been taken unchanged from the Revision class.
54  public const TEXT_CACHE_GROUP = 'revisiontext:10';
55 
59  private $dbLoadBalancer;
60 
64  private $extStoreAccess;
65 
69  private $cache;
70 
74  private $dbDomain;
75 
79  private $cacheExpiry = 604800; // 7 days
80 
84  private $compressBlobs = false;
85 
89  private $legacyEncoding = false;
90 
94  private $useExternalStore = false;
95 
107  public function __construct(
111  $dbDomain = false
112  ) {
113  $this->dbLoadBalancer = $dbLoadBalancer;
114  $this->extStoreAccess = $extStoreAccess;
115  $this->cache = $cache;
116  $this->dbDomain = $dbDomain;
117  }
118 
122  public function getCacheExpiry() {
123  return $this->cacheExpiry;
124  }
125 
129  public function setCacheExpiry( $cacheExpiry ) {
130  Assert::parameterType( 'integer', $cacheExpiry, '$cacheExpiry' );
131 
132  $this->cacheExpiry = $cacheExpiry;
133  }
134 
138  public function getCompressBlobs() {
139  return $this->compressBlobs;
140  }
141 
145  public function setCompressBlobs( $compressBlobs ) {
146  $this->compressBlobs = $compressBlobs;
147  }
148 
153  public function getLegacyEncoding() {
154  return $this->legacyEncoding;
155  }
156 
162  wfDeprecated( __METHOD__ );
163  return null;
164  }
165 
174  public function setLegacyEncoding( $legacyEncoding ) {
175  Assert::parameterType( 'string', $legacyEncoding, '$legacyEncoding' );
176 
177  $this->legacyEncoding = $legacyEncoding;
178  }
179 
183  public function getUseExternalStore() {
185  }
186 
191  Assert::parameterType( 'boolean', $useExternalStore, '$useExternalStore' );
192 
193  $this->useExternalStore = $useExternalStore;
194  }
195 
199  private function getDBLoadBalancer() {
200  return $this->dbLoadBalancer;
201  }
202 
208  private function getDBConnection( $index ) {
209  $lb = $this->getDBLoadBalancer();
210  return $lb->getConnectionRef( $index, [], $this->dbDomain );
211  }
212 
223  public function storeBlob( $data, $hints = [] ) {
224  try {
225  $flags = $this->compressData( $data );
226 
227  # Write to external storage if required
228  if ( $this->useExternalStore ) {
229  // Store and get the URL
230  $data = $this->extStoreAccess->insert( $data, [ 'domain' => $this->dbDomain ] );
231  if ( !$data ) {
232  throw new BlobAccessException( "Failed to store text to external storage" );
233  }
234  if ( $flags ) {
235  $flags .= ',';
236  }
237  $flags .= 'external';
238 
239  // TODO: we could also return an address for the external store directly here.
240  // That would mean bypassing the text table entirely when the external store is
241  // used. We'll need to assess expected fallout before doing that.
242  }
243 
244  $dbw = $this->getDBConnection( DB_MASTER );
245 
246  $old_id = $dbw->nextSequenceValue( 'text_old_id_seq' );
247  $dbw->insert(
248  'text',
249  [
250  'old_id' => $old_id,
251  'old_text' => $data,
252  'old_flags' => $flags,
253  ],
254  __METHOD__
255  );
256 
257  $textId = $dbw->insertId();
258 
259  return self::makeAddressFromTextId( $textId );
260  } catch ( MWException $e ) {
261  throw new BlobAccessException( $e->getMessage(), 0, $e );
262  }
263  }
264 
277  public function getBlob( $blobAddress, $queryFlags = 0 ) {
278  Assert::parameterType( 'string', $blobAddress, '$blobAddress' );
279 
280  $error = null;
281  $blob = $this->cache->getWithSetCallback(
282  $this->getCacheKey( $blobAddress ),
283  $this->getCacheTTL(),
284  function ( $unused, &$ttl, &$setOpts ) use ( $blobAddress, $queryFlags, &$error ) {
285  // Ignore $setOpts; blobs are immutable and negatives are not cached
286  list( $result, $errors ) = $this->fetchBlobs( [ $blobAddress ], $queryFlags );
287  // No negative caching; negative hits on text rows may be due to corrupted replica DBs
288  $error = $errors[$blobAddress] ?? null;
289  return $result[$blobAddress];
290  },
291  [ 'pcGroup' => self::TEXT_CACHE_GROUP, 'pcTTL' => IExpiringStore::TTL_PROC_LONG ]
292  );
293 
294  if ( $error ) {
295  throw new BlobAccessException( $error );
296  }
297 
298  Assert::postcondition( is_string( $blob ), 'Blob must not be null' );
299  return $blob;
300  }
301 
313  public function getBlobBatch( $blobAddresses, $queryFlags = 0 ) {
314  // FIXME: All caching has temporarily been removed in I94c6f9ba7b9caeeb due to T235188.
315  // Caching behavior should be restored by reverting I94c6f9ba7b9caeeb as soon as
316  // the root cause of T235188 has been resolved.
317 
318  list( $blobsByAddress, $errors ) = $this->fetchBlobs( $blobAddresses, $queryFlags );
319 
320  $blobsByAddress = array_map( function ( $blob ) {
321  return $blob === false ? null : $blob;
322  }, $blobsByAddress );
323 
324  $result = StatusValue::newGood( $blobsByAddress );
325  if ( $errors ) {
326  foreach ( $errors as $error ) {
327  $result->warning( 'internalerror', $error );
328  }
329  }
330  return $result;
331  }
332 
343  private function fetchBlobs( $blobAddresses, $queryFlags ) {
344  $textIdToBlobAddress = [];
345  $result = [];
346  $errors = [];
347  foreach ( $blobAddresses as $blobAddress ) {
348  try {
349  list( $schema, $id ) = self::splitBlobAddress( $blobAddress );
350  } catch ( InvalidArgumentException $ex ) {
351  throw new BlobAccessException( $ex->getMessage(), 0, $ex );
352  }
353 
354  // TODO: MCR: also support 'ex' schema with ExternalStore URLs, plus flags encoded in the URL!
355  if ( $schema === 'bad' ) {
356  // Database row was marked as "known bad", no need to trigger an error.
357  wfDebug(
358  __METHOD__
359  . ": loading known-bad content ($blobAddress), returning empty string"
360  );
361  $result[$blobAddress] = '';
362  continue;
363  } elseif ( $schema === 'tt' ) {
364  $textId = intval( $id );
365 
366  if ( $textId < 1 || $id !== (string)$textId ) {
367  $errors[$blobAddress] = "Bad blob address: $blobAddress";
368  $result[$blobAddress] = false;
369  }
370 
371  $textIdToBlobAddress[$textId] = $blobAddress;
372  } else {
373  $errors[$blobAddress] = "Unknown blob address schema: $schema";
374  $result[$blobAddress] = false;
375  continue;
376  }
377  }
378 
379  $textIds = array_keys( $textIdToBlobAddress );
380  if ( !$textIds ) {
381  return [ $result, $errors ];
382  }
383  // Callers doing updates will pass in READ_LATEST as usual. Since the text/blob tables
384  // do not normally get rows changed around, set READ_LATEST_IMMUTABLE in those cases.
385  $queryFlags |= DBAccessObjectUtils::hasFlags( $queryFlags, self::READ_LATEST )
386  ? self::READ_LATEST_IMMUTABLE
387  : 0;
388  list( $index, $options, $fallbackIndex, $fallbackOptions ) =
389  DBAccessObjectUtils::getDBOptions( $queryFlags );
390  // Text data is immutable; check replica DBs first.
391  $dbConnection = $this->getDBConnection( $index );
392  $rows = $dbConnection->select(
393  'text',
394  [ 'old_id', 'old_text', 'old_flags' ],
395  [ 'old_id' => $textIds ],
396  __METHOD__,
397  $options
398  );
399 
400  // Fallback to DB_MASTER in some cases if not all the rows were found, using the appropriate
401  // options, such as FOR UPDATE to avoid missing rows due to REPEATABLE-READ.
402  if ( $dbConnection->numRows( $rows ) !== count( $textIds ) && $fallbackIndex !== null ) {
403  $fetchedTextIds = [];
404  foreach ( $rows as $row ) {
405  $fetchedTextIds[] = $row->old_id;
406  }
407  $missingTextIds = array_diff( $textIds, $fetchedTextIds );
408  $dbConnection = $this->getDBConnection( $fallbackIndex );
409  $rowsFromFallback = $dbConnection->select(
410  'text',
411  [ 'old_id', 'old_text', 'old_flags' ],
412  [ 'old_id' => $missingTextIds ],
413  __METHOD__,
414  $fallbackOptions
415  );
416  $appendIterator = new AppendIterator();
417  $appendIterator->append( $rows );
418  $appendIterator->append( $rowsFromFallback );
419  $rows = $appendIterator;
420  }
421 
422  foreach ( $rows as $row ) {
423  $blobAddress = $textIdToBlobAddress[$row->old_id];
424  $blob = $this->expandBlob( $row->old_text, $row->old_flags, $blobAddress );
425  if ( $blob === false ) {
426  $errors[$blobAddress] = "Bad data in text row {$row->old_id}.";
427  }
428  $result[$blobAddress] = $blob;
429  }
430 
431  // If we're still missing some of the rows, set errors for missing blobs.
432  if ( count( $result ) !== count( $blobAddresses ) ) {
433  foreach ( $blobAddresses as $blobAddress ) {
434  if ( !isset( $result[$blobAddress ] ) ) {
435  $errors[$blobAddress] = "Unable to fetch blob at $blobAddress";
436  $result[$blobAddress] = false;
437  }
438  }
439  }
440  return [ $result, $errors ];
441  }
442 
453  private function getCacheKey( $blobAddress ) {
454  return $this->cache->makeGlobalKey(
455  'SqlBlobStore-blob',
456  $this->dbLoadBalancer->resolveDomainID( $this->dbDomain ),
457  $blobAddress
458  );
459  }
460 
480  public function expandBlob( $raw, $flags, $cacheKey = null ) {
481  if ( is_string( $flags ) ) {
482  $flags = explode( ',', $flags );
483  }
484 
485  // Use external methods for external objects, text in table is URL-only then
486  if ( in_array( 'external', $flags ) ) {
487  $url = $raw;
488  $parts = explode( '://', $url, 2 );
489  if ( count( $parts ) == 1 || $parts[1] == '' ) {
490  return false;
491  }
492 
493  if ( $cacheKey ) {
494  // The cached value should be decompressed, so handle that and return here.
495  return $this->cache->getWithSetCallback(
496  $this->getCacheKey( $cacheKey ),
497  $this->getCacheTTL(),
498  function () use ( $url, $flags ) {
499  // Ignore $setOpts; blobs are immutable and negatives are not cached
500  $blob = $this->extStoreAccess
501  ->fetchFromURL( $url, [ 'domain' => $this->dbDomain ] );
502 
503  return $blob === false ? false : $this->decompressData( $blob, $flags );
504  },
505  [ 'pcGroup' => self::TEXT_CACHE_GROUP, 'pcTTL' => WANObjectCache::TTL_PROC_LONG ]
506  );
507  } else {
508  $blob = $this->extStoreAccess->fetchFromURL( $url, [ 'domain' => $this->dbDomain ] );
509  return $blob === false ? false : $this->decompressData( $blob, $flags );
510  }
511  } else {
512  return $this->decompressData( $raw, $flags );
513  }
514  }
515 
532  public function compressData( &$blob ) {
533  $blobFlags = [];
534 
535  // Revisions not marked as UTF-8 will have legacy decoding applied by decompressData().
536  // XXX: if $this->legacyEncoding is not set, we could skip this. That would however be
537  // risky, since $this->legacyEncoding being set in the future would lead to data corruption.
538  $blobFlags[] = 'utf-8';
539 
540  if ( $this->compressBlobs ) {
541  if ( function_exists( 'gzdeflate' ) ) {
542  $deflated = gzdeflate( $blob );
543 
544  if ( $deflated === false ) {
545  wfLogWarning( __METHOD__ . ': gzdeflate() failed' );
546  } else {
547  $blob = $deflated;
548  $blobFlags[] = 'gzip';
549  }
550  } else {
551  wfDebug( __METHOD__ . " -- no zlib support, not compressing" );
552  }
553  }
554  return implode( ',', $blobFlags );
555  }
556 
572  public function decompressData( $blob, array $blobFlags ) {
573  // Revision::decompressRevisionText accepted false here, so defend against that
574  Assert::parameterType( 'string', $blob, '$blob' );
575 
576  if ( in_array( 'error', $blobFlags ) ) {
577  // Error row, return false
578  return false;
579  }
580 
581  if ( in_array( 'gzip', $blobFlags ) ) {
582  # Deal with optional compression of archived pages.
583  # This can be done periodically via maintenance/compressOld.php, and
584  # as pages are saved if $wgCompressRevisions is set.
585  $blob = gzinflate( $blob );
586 
587  if ( $blob === false ) {
588  wfWarn( __METHOD__ . ': gzinflate() failed' );
589  return false;
590  }
591  }
592 
593  if ( in_array( 'object', $blobFlags ) ) {
594  # Generic compressed storage
595  $obj = unserialize( $blob );
596  if ( !is_object( $obj ) ) {
597  // Invalid object
598  return false;
599  }
600  $blob = $obj->getText();
601  }
602 
603  // Needed to support old revisions left over from from the 1.4 / 1.5 migration.
604  if ( $blob !== false && $this->legacyEncoding
605  && !in_array( 'utf-8', $blobFlags ) && !in_array( 'utf8', $blobFlags )
606  ) {
607  # Old revisions kept around in a legacy encoding?
608  # Upconvert on demand.
609  # ("utf8" checked for compatibility with some broken
610  # conversion scripts 2008-12-30)
611  # Even with //IGNORE iconv can whine about illegal characters in
612  # *input* string. We just ignore those too.
613  # REF: https://bugs.php.net/bug.php?id=37166
614  # REF: https://phabricator.wikimedia.org/T18885
615  AtEase::suppressWarnings();
616  $blob = iconv( $this->legacyEncoding, 'UTF-8//IGNORE', $blob );
617  AtEase::restoreWarnings();
618  }
619 
620  return $blob;
621  }
622 
630  private function getCacheTTL() {
631  if ( $this->cache->getQoS( WANObjectCache::ATTR_EMULATION )
632  <= WANObjectCache::QOS_EMULATION_SQL
633  ) {
634  // Do not cache RDBMs blobs in...the RDBMs store
635  $ttl = WANObjectCache::TTL_UNCACHEABLE;
636  } else {
637  $ttl = $this->cacheExpiry ?: WANObjectCache::TTL_UNCACHEABLE;
638  }
639 
640  return $ttl;
641  }
642 
663  public function getTextIdFromAddress( $address ) {
664  list( $schema, $id, ) = self::splitBlobAddress( $address );
665 
666  if ( $schema !== 'tt' ) {
667  return null;
668  }
669 
670  $textId = intval( $id );
671 
672  if ( !$textId || $id !== (string)$textId ) {
673  throw new InvalidArgumentException( "Malformed text_id: $id" );
674  }
675 
676  return $textId;
677  }
678 
692  public static function makeAddressFromTextId( $id ) {
693  return 'tt:' . $id;
694  }
695 
706  public static function splitBlobAddress( $address ) {
707  if ( !preg_match( '/^([-+.\w]+):([^\s?]+)(\?([^\s]*))?$/', $address, $m ) ) {
708  throw new InvalidArgumentException( "Bad blob address: $address" );
709  }
710 
711  $schema = strtolower( $m[1] );
712  $id = $m[2];
713  $parameters = isset( $m[4] ) ? wfCgiToArray( $m[4] ) : [];
714 
715  return [ $schema, $id, $parameters ];
716  }
717 
718  public function isReadOnly() {
719  if ( $this->useExternalStore && $this->extStoreAccess->isReadOnly() ) {
720  return true;
721  }
722 
723  return ( $this->getDBLoadBalancer()->getReadOnlyReason() !== false );
724  }
725 }
MediaWiki\Storage\SqlBlobStore\getBlob
getBlob( $blobAddress, $queryFlags=0)
Retrieve a blob, given an address.
Definition: SqlBlobStore.php:277
MediaWiki\Storage\SqlBlobStore\getDBLoadBalancer
getDBLoadBalancer()
Definition: SqlBlobStore.php:199
MediaWiki\Storage\BlobAccessException
Exception representing a failure to access a data blob.
Definition: BlobAccessException.php:33
StatusValue
Generic operation result class Has warning/error list, boolean status and arbitrary value.
Definition: StatusValue.php:43
MediaWiki\Storage\SqlBlobStore\getCacheKey
getCacheKey( $blobAddress)
Get a cache key for a given Blob address.
Definition: SqlBlobStore.php:453
MediaWiki\Storage\SqlBlobStore\TEXT_CACHE_GROUP
const TEXT_CACHE_GROUP
Definition: SqlBlobStore.php:54
MediaWiki\Storage\SqlBlobStore\getDBConnection
getDBConnection( $index)
Definition: SqlBlobStore.php:208
MediaWiki\Storage\SqlBlobStore
Service for storing and loading Content objects.
Definition: SqlBlobStore.php:51
MediaWiki\Storage\SqlBlobStore\__construct
__construct(ILoadBalancer $dbLoadBalancer, ExternalStoreAccess $extStoreAccess, WANObjectCache $cache, $dbDomain=false)
Definition: SqlBlobStore.php:107
MediaWiki\Storage\SqlBlobStore\$compressBlobs
bool $compressBlobs
Definition: SqlBlobStore.php:84
MediaWiki\Storage\SqlBlobStore\$dbDomain
string bool $dbDomain
DB domain ID of a wiki or false for the local one.
Definition: SqlBlobStore.php:74
MediaWiki\Storage\SqlBlobStore\getTextIdFromAddress
getTextIdFromAddress( $address)
Returns an ID corresponding to the old_id field in the text table, corresponding to the given $addres...
Definition: SqlBlobStore.php:663
MediaWiki\Storage\SqlBlobStore\splitBlobAddress
static splitBlobAddress( $address)
Splits a blob address into three parts: the schema, the ID, and parameters/flags.
Definition: SqlBlobStore.php:706
MediaWiki\Storage\SqlBlobStore\expandBlob
expandBlob( $raw, $flags, $cacheKey=null)
Expand a raw data blob according to the flags given.
Definition: SqlBlobStore.php:480
MediaWiki\Storage\SqlBlobStore\$dbLoadBalancer
ILoadBalancer $dbLoadBalancer
Definition: SqlBlobStore.php:59
wfLogWarning
wfLogWarning( $msg, $callerOffset=1, $level=E_USER_WARNING)
Send a warning as a PHP error and the debug log.
Definition: GlobalFunctions.php:1086
DBAccessObjectUtils\getDBOptions
static getDBOptions( $bitfield)
Get an appropriate DB index, options, and fallback DB index for a query.
Definition: DBAccessObjectUtils.php:52
IDBAccessObject
Interface for database access objects.
Definition: IDBAccessObject.php:57
MediaWiki\Storage\SqlBlobStore\getBlobBatch
getBlobBatch( $blobAddresses, $queryFlags=0)
A batched version of BlobStore::getBlob.
Definition: SqlBlobStore.php:313
ExternalStoreAccess
Key/value blob storage for a collection of storage medium types (e.g.
Definition: ExternalStoreAccess.php:22
Wikimedia\Rdbms\IDatabase
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:38
MediaWiki\Storage\SqlBlobStore\getCompressBlobs
getCompressBlobs()
Definition: SqlBlobStore.php:138
MediaWiki\Storage\SqlBlobStore\getLegacyEncoding
getLegacyEncoding()
Definition: SqlBlobStore.php:153
IExpiringStore
Generic interface providing TTL constants for lightweight expiring object stores.
Definition: IExpiringStore.php:13
MWException
MediaWiki exception.
Definition: MWException.php:29
wfDeprecated
wfDeprecated( $function, $version=false, $component=false, $callerOffset=2)
Logs a warning that $function is deprecated.
Definition: GlobalFunctions.php:1026
MediaWiki\Storage\SqlBlobStore\getLegacyEncodingConversionLang
getLegacyEncodingConversionLang()
Definition: SqlBlobStore.php:161
MediaWiki\Storage\SqlBlobStore\getCacheTTL
getCacheTTL()
Get the text cache TTL.
Definition: SqlBlobStore.php:630
MediaWiki\Storage\SqlBlobStore\$extStoreAccess
ExternalStoreAccess $extStoreAccess
Definition: SqlBlobStore.php:64
MediaWiki\Storage\SqlBlobStore\isReadOnly
isReadOnly()
Check if the blob metadata or backing blob data store is read-only.
Definition: SqlBlobStore.php:718
$blob
$blob
Definition: testCompression.php:70
MediaWiki\Storage\SqlBlobStore\$useExternalStore
boolean $useExternalStore
Definition: SqlBlobStore.php:94
MediaWiki\Storage\SqlBlobStore\makeAddressFromTextId
static makeAddressFromTextId( $id)
Returns an address referring to content stored in the text table row with the given ID.
Definition: SqlBlobStore.php:692
wfCgiToArray
wfCgiToArray( $query)
This is the logical opposite of wfArrayToCgi(): it accepts a query string as its argument and returns...
Definition: GlobalFunctions.php:391
DB_MASTER
const DB_MASTER
Definition: defines.php:26
wfDebug
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
Definition: GlobalFunctions.php:909
DBAccessObjectUtils
Helper class for DAO classes.
Definition: DBAccessObjectUtils.php:29
DBAccessObjectUtils\hasFlags
static hasFlags( $bitfield, $flags)
Definition: DBAccessObjectUtils.php:35
MediaWiki\Storage\SqlBlobStore\storeBlob
storeBlob( $data, $hints=[])
Stores an arbitrary blob of data and returns an address that can be used with getBlob() to retrieve t...
Definition: SqlBlobStore.php:223
StatusValue\newGood
static newGood( $value=null)
Factory function for good results.
Definition: StatusValue.php:82
WANObjectCache
Multi-datacenter aware caching interface.
Definition: WANObjectCache.php:125
MediaWiki\Storage\SqlBlobStore\fetchBlobs
fetchBlobs( $blobAddresses, $queryFlags)
MCR migration note: this corresponds to Revision::fetchText.
Definition: SqlBlobStore.php:343
MediaWiki\Storage\SqlBlobStore\getUseExternalStore
getUseExternalStore()
Definition: SqlBlobStore.php:183
MediaWiki\Storage
Definition: BlobAccessException.php:23
MediaWiki\Storage\SqlBlobStore\getCacheExpiry
getCacheExpiry()
Definition: SqlBlobStore.php:122
MediaWiki\Storage\SqlBlobStore\setLegacyEncoding
setLegacyEncoding( $legacyEncoding)
Set the legacy encoding to assume for blobs that do not have the utf-8 flag set.
Definition: SqlBlobStore.php:174
MediaWiki\Storage\SqlBlobStore\$cacheExpiry
int $cacheExpiry
Definition: SqlBlobStore.php:79
MediaWiki\Storage\BlobStore
Service for loading and storing data blobs.
Definition: BlobStore.php:35
unserialize
unserialize( $serialized)
Definition: ApiMessageTrait.php:146
MediaWiki\Storage\SqlBlobStore\decompressData
decompressData( $blob, array $blobFlags)
Re-converts revision text according to its flags.
Definition: SqlBlobStore.php:572
MediaWiki\Storage\SqlBlobStore\setUseExternalStore
setUseExternalStore( $useExternalStore)
Definition: SqlBlobStore.php:190
MediaWiki\Storage\SqlBlobStore\setCompressBlobs
setCompressBlobs( $compressBlobs)
Definition: SqlBlobStore.php:145
wfWarn
wfWarn( $msg, $callerOffset=1, $level=E_USER_NOTICE)
Send a warning either to the debug log or in a PHP error depending on $wgDevelopmentWarnings.
Definition: GlobalFunctions.php:1073
MediaWiki\Storage\SqlBlobStore\$cache
WANObjectCache $cache
Definition: SqlBlobStore.php:69
MediaWiki\Storage\SqlBlobStore\compressData
compressData(&$blob)
If $wgCompressRevisions is enabled, we will compress data.
Definition: SqlBlobStore.php:532
MediaWiki\Storage\SqlBlobStore\$legacyEncoding
bool string $legacyEncoding
Definition: SqlBlobStore.php:89
MediaWiki\Storage\SqlBlobStore\setCacheExpiry
setCacheExpiry( $cacheExpiry)
Definition: SqlBlobStore.php:129
Wikimedia\Rdbms\ILoadBalancer
Database cluster connection, tracking, load balancing, and transaction manager interface.
Definition: ILoadBalancer.php:81