* Use local context to get messages
[lhc/web/wiklou.git] / includes / LocalisationCache.php
1 <?php
2
3 define( 'MW_LC_VERSION', 2 );
4
5 /**
6 * Class for caching the contents of localisation files, Messages*.php
7 * and *.i18n.php.
8 *
9 * An instance of this class is available using Language::getLocalisationCache().
10 *
11 * The values retrieved from here are merged, containing items from extension
12 * files, core messages files and the language fallback sequence (e.g. zh-cn ->
13 * zh-hans -> en ). Some common errors are corrected, for example namespace
14 * names with spaces instead of underscores, but heavyweight processing, such
15 * as grammatical transformation, is done by the caller.
16 */
17 class LocalisationCache {
18 /** Configuration associative array */
19 var $conf;
20
21 /**
22 * True if recaching should only be done on an explicit call to recache().
23 * Setting this reduces the overhead of cache freshness checking, which
24 * requires doing a stat() for every extension i18n file.
25 */
26 var $manualRecache = false;
27
28 /**
29 * True to treat all files as expired until they are regenerated by this object.
30 */
31 var $forceRecache = false;
32
33 /**
34 * The cache data. 3-d array, where the first key is the language code,
35 * the second key is the item key e.g. 'messages', and the third key is
36 * an item specific subkey index. Some items are not arrays and so for those
37 * items, there are no subkeys.
38 */
39 var $data = array();
40
41 /**
42 * The persistent store object. An instance of LCStore.
43 *
44 * @var LCStore
45 */
46 var $store;
47
48 /**
49 * A 2-d associative array, code/key, where presence indicates that the item
50 * is loaded. Value arbitrary.
51 *
52 * For split items, if set, this indicates that all of the subitems have been
53 * loaded.
54 */
55 var $loadedItems = array();
56
57 /**
58 * A 3-d associative array, code/key/subkey, where presence indicates that
59 * the subitem is loaded. Only used for the split items, i.e. messages.
60 */
61 var $loadedSubitems = array();
62
63 /**
64 * An array where presence of a key indicates that that language has been
65 * initialised. Initialisation includes checking for cache expiry and doing
66 * any necessary updates.
67 */
68 var $initialisedLangs = array();
69
70 /**
71 * An array mapping non-existent pseudo-languages to fallback languages. This
72 * is filled by initShallowFallback() when data is requested from a language
73 * that lacks a Messages*.php file.
74 */
75 var $shallowFallbacks = array();
76
77 /**
78 * An array where the keys are codes that have been recached by this instance.
79 */
80 var $recachedLangs = array();
81
82 /**
83 * All item keys
84 */
85 static public $allKeys = array(
86 'fallback', 'namespaceNames', 'bookstoreList',
87 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
88 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
89 'linkTrail', 'namespaceAliases',
90 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
91 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
92 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
93 'digitGroupingPattern'
94 );
95
96 /**
97 * Keys for items which consist of associative arrays, which may be merged
98 * by a fallback sequence.
99 */
100 static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
101 'dateFormats', 'imageFiles', 'preloadedMessages',
102 );
103
104 /**
105 * Keys for items which are a numbered array.
106 */
107 static public $mergeableListKeys = array( 'extraUserToggles' );
108
109 /**
110 * Keys for items which contain an array of arrays of equivalent aliases
111 * for each subitem. The aliases may be merged by a fallback sequence.
112 */
113 static public $mergeableAliasListKeys = array( 'specialPageAliases' );
114
115 /**
116 * Keys for items which contain an associative array, and may be merged if
117 * the primary value contains the special array key "inherit". That array
118 * key is removed after the first merge.
119 */
120 static public $optionalMergeKeys = array( 'bookstoreList' );
121
122 /**
123 * Keys for items that are formatted like $magicWords
124 */
125 static public $magicWordKeys = array( 'magicWords' );
126
127 /**
128 * Keys for items where the subitems are stored in the backend separately.
129 */
130 static public $splitKeys = array( 'messages' );
131
132 /**
133 * Keys which are loaded automatically by initLanguage()
134 */
135 static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
136
137 var $mergeableKeys = null;
138
139 /**
140 * Constructor.
141 * For constructor parameters, see the documentation in DefaultSettings.php
142 * for $wgLocalisationCacheConf.
143 *
144 * @param $conf Array
145 */
146 function __construct( $conf ) {
147 global $wgCacheDirectory;
148
149 $this->conf = $conf;
150 $storeConf = array();
151 if ( !empty( $conf['storeClass'] ) ) {
152 $storeClass = $conf['storeClass'];
153 } else {
154 switch ( $conf['store'] ) {
155 case 'files':
156 case 'file':
157 $storeClass = 'LCStore_CDB';
158 break;
159 case 'db':
160 $storeClass = 'LCStore_DB';
161 break;
162 case 'accel':
163 $storeClass = 'LCStore_Accel';
164 break;
165 case 'detect':
166 $storeClass = $wgCacheDirectory ? 'LCStore_CDB' : 'LCStore_DB';
167 break;
168 default:
169 throw new MWException(
170 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
171 }
172 }
173
174 wfDebug( get_class( $this ) . ": using store $storeClass\n" );
175 if ( !empty( $conf['storeDirectory'] ) ) {
176 $storeConf['directory'] = $conf['storeDirectory'];
177 }
178
179 $this->store = new $storeClass( $storeConf );
180 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
181 if ( isset( $conf[$var] ) ) {
182 $this->$var = $conf[$var];
183 }
184 }
185 }
186
187 /**
188 * Returns true if the given key is mergeable, that is, if it is an associative
189 * array which can be merged through a fallback sequence.
190 * @param $key
191 * @return bool
192 */
193 public function isMergeableKey( $key ) {
194 if ( $this->mergeableKeys === null ) {
195 $this->mergeableKeys = array_flip( array_merge(
196 self::$mergeableMapKeys,
197 self::$mergeableListKeys,
198 self::$mergeableAliasListKeys,
199 self::$optionalMergeKeys,
200 self::$magicWordKeys
201 ) );
202 }
203 return isset( $this->mergeableKeys[$key] );
204 }
205
206 /**
207 * Get a cache item.
208 *
209 * Warning: this may be slow for split items (messages), since it will
210 * need to fetch all of the subitems from the cache individually.
211 * @param $code
212 * @param $key
213 * @return mixed
214 */
215 public function getItem( $code, $key ) {
216 if ( !isset( $this->loadedItems[$code][$key] ) ) {
217 wfProfileIn( __METHOD__.'-load' );
218 $this->loadItem( $code, $key );
219 wfProfileOut( __METHOD__.'-load' );
220 }
221
222 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
223 return $this->shallowFallbacks[$code];
224 }
225
226 return $this->data[$code][$key];
227 }
228
229 /**
230 * Get a subitem, for instance a single message for a given language.
231 * @param $code
232 * @param $key
233 * @param $subkey
234 * @return null
235 */
236 public function getSubitem( $code, $key, $subkey ) {
237 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
238 !isset( $this->loadedItems[$code][$key] ) ) {
239 wfProfileIn( __METHOD__.'-load' );
240 $this->loadSubitem( $code, $key, $subkey );
241 wfProfileOut( __METHOD__.'-load' );
242 }
243
244 if ( isset( $this->data[$code][$key][$subkey] ) ) {
245 return $this->data[$code][$key][$subkey];
246 } else {
247 return null;
248 }
249 }
250
251 /**
252 * Get the list of subitem keys for a given item.
253 *
254 * This is faster than array_keys($lc->getItem(...)) for the items listed in
255 * self::$splitKeys.
256 *
257 * Will return null if the item is not found, or false if the item is not an
258 * array.
259 * @param $code
260 * @param $key
261 * @return bool|null|string
262 */
263 public function getSubitemList( $code, $key ) {
264 if ( in_array( $key, self::$splitKeys ) ) {
265 return $this->getSubitem( $code, 'list', $key );
266 } else {
267 $item = $this->getItem( $code, $key );
268 if ( is_array( $item ) ) {
269 return array_keys( $item );
270 } else {
271 return false;
272 }
273 }
274 }
275
276 /**
277 * Load an item into the cache.
278 * @param $code
279 * @param $key
280 */
281 protected function loadItem( $code, $key ) {
282 if ( !isset( $this->initialisedLangs[$code] ) ) {
283 $this->initLanguage( $code );
284 }
285
286 // Check to see if initLanguage() loaded it for us
287 if ( isset( $this->loadedItems[$code][$key] ) ) {
288 return;
289 }
290
291 if ( isset( $this->shallowFallbacks[$code] ) ) {
292 $this->loadItem( $this->shallowFallbacks[$code], $key );
293 return;
294 }
295
296 if ( in_array( $key, self::$splitKeys ) ) {
297 $subkeyList = $this->getSubitem( $code, 'list', $key );
298 foreach ( $subkeyList as $subkey ) {
299 if ( isset( $this->data[$code][$key][$subkey] ) ) {
300 continue;
301 }
302 $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
303 }
304 } else {
305 $this->data[$code][$key] = $this->store->get( $code, $key );
306 }
307
308 $this->loadedItems[$code][$key] = true;
309 }
310
311 /**
312 * Load a subitem into the cache
313 * @param $code
314 * @param $key
315 * @param $subkey
316 * @return
317 */
318 protected function loadSubitem( $code, $key, $subkey ) {
319 if ( !in_array( $key, self::$splitKeys ) ) {
320 $this->loadItem( $code, $key );
321 return;
322 }
323
324 if ( !isset( $this->initialisedLangs[$code] ) ) {
325 $this->initLanguage( $code );
326 }
327
328 // Check to see if initLanguage() loaded it for us
329 if ( isset( $this->loadedItems[$code][$key] ) ||
330 isset( $this->loadedSubitems[$code][$key][$subkey] ) ) {
331 return;
332 }
333
334 if ( isset( $this->shallowFallbacks[$code] ) ) {
335 $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
336 return;
337 }
338
339 $value = $this->store->get( $code, "$key:$subkey" );
340 $this->data[$code][$key][$subkey] = $value;
341 $this->loadedSubitems[$code][$key][$subkey] = true;
342 }
343
344 /**
345 * Returns true if the cache identified by $code is missing or expired.
346 * @return bool
347 */
348 public function isExpired( $code ) {
349 if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
350 wfDebug( __METHOD__."($code): forced reload\n" );
351 return true;
352 }
353
354 $deps = $this->store->get( $code, 'deps' );
355 $keys = $this->store->get( $code, 'list', 'messages' );
356 $preload = $this->store->get( $code, 'preload' );
357 // Different keys may expire separately, at least in LCStore_Accel
358 if ( $deps === null || $keys === null || $preload === null ) {
359 wfDebug( __METHOD__."($code): cache missing, need to make one\n" );
360 return true;
361 }
362
363 foreach ( $deps as $dep ) {
364 // Because we're unserializing stuff from cache, we
365 // could receive objects of classes that don't exist
366 // anymore (e.g. uninstalled extensions)
367 // When this happens, always expire the cache
368 if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
369 wfDebug( __METHOD__."($code): cache for $code expired due to " .
370 get_class( $dep ) . "\n" );
371 return true;
372 }
373 }
374
375 return false;
376 }
377
378 /**
379 * Initialise a language in this object. Rebuild the cache if necessary.
380 * @param $code
381 */
382 protected function initLanguage( $code ) {
383 if ( isset( $this->initialisedLangs[$code] ) ) {
384 return;
385 }
386
387 $this->initialisedLangs[$code] = true;
388
389 # If the code is of the wrong form for a Messages*.php file, do a shallow fallback
390 if ( !Language::isValidBuiltInCode( $code ) ) {
391 $this->initShallowFallback( $code, 'en' );
392 return;
393 }
394
395 # Recache the data if necessary
396 if ( !$this->manualRecache && $this->isExpired( $code ) ) {
397 if ( file_exists( Language::getMessagesFileName( $code ) ) ) {
398 $this->recache( $code );
399 } elseif ( $code === 'en' ) {
400 throw new MWException( 'MessagesEn.php is missing.' );
401 } else {
402 $this->initShallowFallback( $code, 'en' );
403 }
404 return;
405 }
406
407 # Preload some stuff
408 $preload = $this->getItem( $code, 'preload' );
409 if ( $preload === null ) {
410 if ( $this->manualRecache ) {
411 // No Messages*.php file. Do shallow fallback to en.
412 if ( $code === 'en' ) {
413 throw new MWException( 'No localisation cache found for English. ' .
414 'Please run maintenance/rebuildLocalisationCache.php.' );
415 }
416 $this->initShallowFallback( $code, 'en' );
417 return;
418 } else {
419 throw new MWException( 'Invalid or missing localisation cache.' );
420 }
421 }
422 $this->data[$code] = $preload;
423 foreach ( $preload as $key => $item ) {
424 if ( in_array( $key, self::$splitKeys ) ) {
425 foreach ( $item as $subkey => $subitem ) {
426 $this->loadedSubitems[$code][$key][$subkey] = true;
427 }
428 } else {
429 $this->loadedItems[$code][$key] = true;
430 }
431 }
432 }
433
434 /**
435 * Create a fallback from one language to another, without creating a
436 * complete persistent cache.
437 * @param $primaryCode
438 * @param $fallbackCode
439 */
440 public function initShallowFallback( $primaryCode, $fallbackCode ) {
441 $this->data[$primaryCode] =& $this->data[$fallbackCode];
442 $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
443 $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
444 $this->shallowFallbacks[$primaryCode] = $fallbackCode;
445 }
446
447 /**
448 * Read a PHP file containing localisation data.
449 * @param $_fileName
450 * @param $_fileType
451 * @return array
452 */
453 protected function readPHPFile( $_fileName, $_fileType ) {
454 // Disable APC caching
455 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
456 include( $_fileName );
457 ini_set( 'apc.cache_by_default', $_apcEnabled );
458
459 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
460 $data = compact( self::$allKeys );
461 } elseif ( $_fileType == 'aliases' ) {
462 $data = compact( 'aliases' );
463 } else {
464 throw new MWException( __METHOD__.": Invalid file type: $_fileType" );
465 }
466
467 return $data;
468 }
469
470 /**
471 * Merge two localisation values, a primary and a fallback, overwriting the
472 * primary value in place.
473 * @param $key
474 * @param $value
475 * @param $fallbackValue
476 */
477 protected function mergeItem( $key, &$value, $fallbackValue ) {
478 if ( !is_null( $value ) ) {
479 if ( !is_null( $fallbackValue ) ) {
480 if ( in_array( $key, self::$mergeableMapKeys ) ) {
481 $value = $value + $fallbackValue;
482 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
483 $value = array_unique( array_merge( $fallbackValue, $value ) );
484 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
485 $value = array_merge_recursive( $value, $fallbackValue );
486 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
487 if ( !empty( $value['inherit'] ) ) {
488 $value = array_merge( $fallbackValue, $value );
489 }
490
491 if ( isset( $value['inherit'] ) ) {
492 unset( $value['inherit'] );
493 }
494 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
495 $this->mergeMagicWords( $value, $fallbackValue );
496 }
497 }
498 } else {
499 $value = $fallbackValue;
500 }
501 }
502
503 /**
504 * @param $value
505 * @param $fallbackValue
506 */
507 protected function mergeMagicWords( &$value, $fallbackValue ) {
508 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
509 if ( !isset( $value[$magicName] ) ) {
510 $value[$magicName] = $fallbackInfo;
511 } else {
512 $oldSynonyms = array_slice( $fallbackInfo, 1 );
513 $newSynonyms = array_slice( $value[$magicName], 1 );
514 $synonyms = array_values( array_unique( array_merge(
515 $newSynonyms, $oldSynonyms ) ) );
516 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
517 }
518 }
519 }
520
521 /**
522 * Given an array mapping language code to localisation value, such as is
523 * found in extension *.i18n.php files, iterate through a fallback sequence
524 * to merge the given data with an existing primary value.
525 *
526 * Returns true if any data from the extension array was used, false
527 * otherwise.
528 * @param $codeSequence
529 * @param $key
530 * @param $value
531 * @param $fallbackValue
532 * @return bool
533 */
534 protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
535 $used = false;
536 foreach ( $codeSequence as $code ) {
537 if ( isset( $fallbackValue[$code] ) ) {
538 $this->mergeItem( $key, $value, $fallbackValue[$code] );
539 $used = true;
540 }
541 }
542
543 return $used;
544 }
545
546 /**
547 * Load localisation data for a given language for both core and extensions
548 * and save it to the persistent cache store and the process cache
549 * @param $code
550 */
551 public function recache( $code ) {
552 global $wgExtensionMessagesFiles;
553 wfProfileIn( __METHOD__ );
554
555 if ( !$code ) {
556 throw new MWException( "Invalid language code requested" );
557 }
558 $this->recachedLangs[$code] = true;
559
560 # Initial values
561 $initialData = array_combine(
562 self::$allKeys,
563 array_fill( 0, count( self::$allKeys ), null ) );
564 $coreData = $initialData;
565 $deps = array();
566
567 # Load the primary localisation from the source file
568 $fileName = Language::getMessagesFileName( $code );
569 if ( !file_exists( $fileName ) ) {
570 wfDebug( __METHOD__.": no localisation file for $code, using fallback to en\n" );
571 $coreData['fallback'] = 'en';
572 } else {
573 $deps[] = new FileDependency( $fileName );
574 $data = $this->readPHPFile( $fileName, 'core' );
575 wfDebug( __METHOD__.": got localisation for $code from source\n" );
576
577 # Merge primary localisation
578 foreach ( $data as $key => $value ) {
579 $this->mergeItem( $key, $coreData[$key], $value );
580 }
581
582 }
583
584 # Fill in the fallback if it's not there already
585 if ( is_null( $coreData['fallback'] ) ) {
586 $coreData['fallback'] = $code === 'en' ? false : 'en';
587 }
588
589 if ( $coreData['fallback'] === false ) {
590 $coreData['fallbackSequence'] = array();
591 } else {
592 $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
593 $len = count( $coreData['fallbackSequence'] );
594
595 # Ensure that the sequence ends at en
596 if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
597 $coreData['fallbackSequence'][] = 'en';
598 }
599
600 # Load the fallback localisation item by item and merge it
601 foreach ( $coreData['fallbackSequence'] as $fbCode ) {
602 # Load the secondary localisation from the source file to
603 # avoid infinite cycles on cyclic fallbacks
604 $fbFilename = Language::getMessagesFileName( $fbCode );
605
606 if ( !file_exists( $fbFilename ) ) {
607 continue;
608 }
609
610 $deps[] = new FileDependency( $fbFilename );
611 $fbData = $this->readPHPFile( $fbFilename, 'core' );
612
613 foreach ( self::$allKeys as $key ) {
614 if ( !isset( $fbData[$key] ) ) {
615 continue;
616 }
617
618 if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
619 $this->mergeItem( $key, $coreData[$key], $fbData[$key] );
620 }
621 }
622 }
623 }
624
625 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
626
627 # Load the extension localisations
628 # This is done after the core because we know the fallback sequence now.
629 # But it has a higher precedence for merging so that we can support things
630 # like site-specific message overrides.
631 $allData = $initialData;
632 foreach ( $wgExtensionMessagesFiles as $fileName ) {
633 $data = $this->readPHPFile( $fileName, 'extension' );
634 $used = false;
635
636 foreach ( $data as $key => $item ) {
637 if( $this->mergeExtensionItem( $codeSequence, $key, $allData[$key], $item ) ) {
638 $used = true;
639 }
640 }
641
642 if ( $used ) {
643 $deps[] = new FileDependency( $fileName );
644 }
645 }
646
647 # Merge core data into extension data
648 foreach ( $coreData as $key => $item ) {
649 $this->mergeItem( $key, $allData[$key], $item );
650 }
651
652 # Add cache dependencies for any referenced globals
653 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
654 $deps['version'] = new ConstantDependency( 'MW_LC_VERSION' );
655
656 # Add dependencies to the cache entry
657 $allData['deps'] = $deps;
658
659 # Replace spaces with underscores in namespace names
660 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
661
662 # And do the same for special page aliases. $page is an array.
663 foreach ( $allData['specialPageAliases'] as &$page ) {
664 $page = str_replace( ' ', '_', $page );
665 }
666 # Decouple the reference to prevent accidental damage
667 unset($page);
668
669 # Set the list keys
670 $allData['list'] = array();
671 foreach ( self::$splitKeys as $key ) {
672 $allData['list'][$key] = array_keys( $allData[$key] );
673 }
674
675 # Run hooks
676 wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData ) );
677
678 if ( is_null( $allData['namespaceNames'] ) ) {
679 throw new MWException( __METHOD__.': Localisation data failed sanity check! ' .
680 'Check that your languages/messages/MessagesEn.php file is intact.' );
681 }
682
683 # Set the preload key
684 $allData['preload'] = $this->buildPreload( $allData );
685
686 # Save to the process cache and register the items loaded
687 $this->data[$code] = $allData;
688 foreach ( $allData as $key => $item ) {
689 $this->loadedItems[$code][$key] = true;
690 }
691
692 # Save to the persistent cache
693 $this->store->startWrite( $code );
694 foreach ( $allData as $key => $value ) {
695 if ( in_array( $key, self::$splitKeys ) ) {
696 foreach ( $value as $subkey => $subvalue ) {
697 $this->store->set( "$key:$subkey", $subvalue );
698 }
699 } else {
700 $this->store->set( $key, $value );
701 }
702 }
703 $this->store->finishWrite();
704
705 # Clear out the MessageBlobStore
706 # HACK: If using a null (i.e. disabled) storage backend, we
707 # can't write to the MessageBlobStore either
708 if ( !$this->store instanceof LCStore_Null ) {
709 MessageBlobStore::clear();
710 }
711
712 wfProfileOut( __METHOD__ );
713 }
714
715 /**
716 * Build the preload item from the given pre-cache data.
717 *
718 * The preload item will be loaded automatically, improving performance
719 * for the commonly-requested items it contains.
720 * @param $data
721 * @return array
722 */
723 protected function buildPreload( $data ) {
724 $preload = array( 'messages' => array() );
725 foreach ( self::$preloadedKeys as $key ) {
726 $preload[$key] = $data[$key];
727 }
728
729 foreach ( $data['preloadedMessages'] as $subkey ) {
730 if ( isset( $data['messages'][$subkey] ) ) {
731 $subitem = $data['messages'][$subkey];
732 } else {
733 $subitem = null;
734 }
735 $preload['messages'][$subkey] = $subitem;
736 }
737
738 return $preload;
739 }
740
741 /**
742 * Unload the data for a given language from the object cache.
743 * Reduces memory usage.
744 * @param $code
745 */
746 public function unload( $code ) {
747 unset( $this->data[$code] );
748 unset( $this->loadedItems[$code] );
749 unset( $this->loadedSubitems[$code] );
750 unset( $this->initialisedLangs[$code] );
751
752 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
753 if ( $fbCode === $code ) {
754 $this->unload( $shallowCode );
755 }
756 }
757 }
758
759 /**
760 * Unload all data
761 */
762 public function unloadAll() {
763 foreach ( $this->initialisedLangs as $lang => $unused ) {
764 $this->unload( $lang );
765 }
766 }
767
768 /**
769 * Disable the storage backend
770 */
771 public function disableBackend() {
772 $this->store = new LCStore_Null;
773 $this->manualRecache = false;
774 }
775 }
776
777 /**
778 * Interface for the persistence layer of LocalisationCache.
779 *
780 * The persistence layer is two-level hierarchical cache. The first level
781 * is the language, the second level is the item or subitem.
782 *
783 * Since the data for a whole language is rebuilt in one operation, it needs
784 * to have a fast and atomic method for deleting or replacing all of the
785 * current data for a given language. The interface reflects this bulk update
786 * operation. Callers writing to the cache must first call startWrite(), then
787 * will call set() a couple of thousand times, then will call finishWrite()
788 * to commit the operation. When finishWrite() is called, the cache is
789 * expected to delete all data previously stored for that language.
790 *
791 * The values stored are PHP variables suitable for serialize(). Implementations
792 * of LCStore are responsible for serializing and unserializing.
793 */
794 interface LCStore {
795 /**
796 * Get a value.
797 * @param $code string Language code
798 * @param $key string Cache key
799 */
800 function get( $code, $key );
801
802 /**
803 * Start a write transaction.
804 * @param $code Language code
805 */
806 function startWrite( $code );
807
808 /**
809 * Finish a write transaction.
810 */
811 function finishWrite();
812
813 /**
814 * Set a key to a given value. startWrite() must be called before this
815 * is called, and finishWrite() must be called afterwards.
816 * @param $key
817 * @param $value
818 */
819 function set( $key, $value );
820 }
821
822 /**
823 * LCStore implementation which uses PHP accelerator to store data.
824 * This will work if one of XCache, WinCache or APC cacher is configured.
825 * (See ObjectCache.php)
826 */
827 class LCStore_Accel implements LCStore {
828 var $currentLang;
829 var $keys;
830
831 public function __construct() {
832 $this->cache = wfGetCache( CACHE_ACCEL );
833 }
834
835 public function get( $code, $key ) {
836 $k = wfMemcKey( 'l10n', $code, 'k', $key );
837 $r = $this->cache->get( $k );
838 return $r === false ? null : $r;
839 }
840
841 public function startWrite( $code ) {
842 $k = wfMemcKey( 'l10n', $code, 'l' );
843 $keys = $this->cache->get( $k );
844 if ( $keys ) {
845 foreach ( $keys as $k ) {
846 $this->cache->delete( $k );
847 }
848 }
849 $this->currentLang = $code;
850 $this->keys = array();
851 }
852
853 public function finishWrite() {
854 if ( $this->currentLang ) {
855 $k = wfMemcKey( 'l10n', $this->currentLang, 'l' );
856 $this->cache->set( $k, array_keys( $this->keys ) );
857 }
858 $this->currentLang = null;
859 $this->keys = array();
860 }
861
862 public function set( $key, $value ) {
863 if ( $this->currentLang ) {
864 $k = wfMemcKey( 'l10n', $this->currentLang, 'k', $key );
865 $this->keys[$k] = true;
866 $this->cache->set( $k, $value );
867 }
868 }
869 }
870
871 /**
872 * LCStore implementation which uses the standard DB functions to store data.
873 * This will work on any MediaWiki installation.
874 */
875 class LCStore_DB implements LCStore {
876 var $currentLang;
877 var $writesDone = false;
878
879 /**
880 * @var DatabaseBase
881 */
882 var $dbw;
883 var $batch;
884 var $readOnly = false;
885
886 public function get( $code, $key ) {
887 if ( $this->writesDone ) {
888 $db = wfGetDB( DB_MASTER );
889 } else {
890 $db = wfGetDB( DB_SLAVE );
891 }
892 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
893 array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
894 if ( $row ) {
895 return unserialize( $row->lc_value );
896 } else {
897 return null;
898 }
899 }
900
901 public function startWrite( $code ) {
902 if ( $this->readOnly ) {
903 return;
904 }
905
906 if ( !$code ) {
907 throw new MWException( __METHOD__.": Invalid language \"$code\"" );
908 }
909
910 $this->dbw = wfGetDB( DB_MASTER );
911 try {
912 $this->dbw->begin( __METHOD__ );
913 $this->dbw->delete( 'l10n_cache', array( 'lc_lang' => $code ), __METHOD__ );
914 } catch ( DBQueryError $e ) {
915 if ( $this->dbw->wasReadOnlyError() ) {
916 $this->readOnly = true;
917 $this->dbw->rollback( __METHOD__ );
918 $this->dbw->ignoreErrors( false );
919 return;
920 } else {
921 throw $e;
922 }
923 }
924
925 $this->currentLang = $code;
926 $this->batch = array();
927 }
928
929 public function finishWrite() {
930 if ( $this->readOnly ) {
931 return;
932 }
933
934 if ( $this->batch ) {
935 $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
936 }
937
938 $this->dbw->commit( __METHOD__ );
939 $this->currentLang = null;
940 $this->dbw = null;
941 $this->batch = array();
942 $this->writesDone = true;
943 }
944
945 public function set( $key, $value ) {
946 if ( $this->readOnly ) {
947 return;
948 }
949
950 if ( is_null( $this->currentLang ) ) {
951 throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
952 }
953
954 $this->batch[] = array(
955 'lc_lang' => $this->currentLang,
956 'lc_key' => $key,
957 'lc_value' => serialize( $value ) );
958
959 if ( count( $this->batch ) >= 100 ) {
960 $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
961 $this->batch = array();
962 }
963 }
964 }
965
966 /**
967 * LCStore implementation which stores data as a collection of CDB files in the
968 * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
969 * will throw an exception.
970 *
971 * Profiling indicates that on Linux, this implementation outperforms MySQL if
972 * the directory is on a local filesystem and there is ample kernel cache
973 * space. The performance advantage is greater when the DBA extension is
974 * available than it is with the PHP port.
975 *
976 * See Cdb.php and http://cr.yp.to/cdb.html
977 */
978 class LCStore_CDB implements LCStore {
979 var $readers, $writer, $currentLang, $directory;
980
981 function __construct( $conf = array() ) {
982 global $wgCacheDirectory;
983
984 if ( isset( $conf['directory'] ) ) {
985 $this->directory = $conf['directory'];
986 } else {
987 $this->directory = $wgCacheDirectory;
988 }
989 }
990
991 public function get( $code, $key ) {
992 if ( !isset( $this->readers[$code] ) ) {
993 $fileName = $this->getFileName( $code );
994
995 if ( !file_exists( $fileName ) ) {
996 $this->readers[$code] = false;
997 } else {
998 $this->readers[$code] = CdbReader::open( $fileName );
999 }
1000 }
1001
1002 if ( !$this->readers[$code] ) {
1003 return null;
1004 } else {
1005 $value = $this->readers[$code]->get( $key );
1006
1007 if ( $value === false ) {
1008 return null;
1009 }
1010 return unserialize( $value );
1011 }
1012 }
1013
1014 public function startWrite( $code ) {
1015 if ( !file_exists( $this->directory ) ) {
1016 if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1017 throw new MWException( "Unable to create the localisation store " .
1018 "directory \"{$this->directory}\"" );
1019 }
1020 }
1021
1022 // Close reader to stop permission errors on write
1023 if( !empty($this->readers[$code]) ) {
1024 $this->readers[$code]->close();
1025 }
1026
1027 $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1028 $this->currentLang = $code;
1029 }
1030
1031 public function finishWrite() {
1032 // Close the writer
1033 $this->writer->close();
1034 $this->writer = null;
1035 unset( $this->readers[$this->currentLang] );
1036 $this->currentLang = null;
1037 }
1038
1039 public function set( $key, $value ) {
1040 if ( is_null( $this->writer ) ) {
1041 throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
1042 }
1043 $this->writer->set( $key, serialize( $value ) );
1044 }
1045
1046 protected function getFileName( $code ) {
1047 if ( !$code || strpos( $code, '/' ) !== false ) {
1048 throw new MWException( __METHOD__.": Invalid language \"$code\"" );
1049 }
1050 return "{$this->directory}/l10n_cache-$code.cdb";
1051 }
1052 }
1053
1054 /**
1055 * Null store backend, used to avoid DB errors during install
1056 */
1057 class LCStore_Null implements LCStore {
1058 public function get( $code, $key ) {
1059 return null;
1060 }
1061
1062 public function startWrite( $code ) {}
1063 public function finishWrite() {}
1064 public function set( $key, $value ) {}
1065 }
1066
1067 /**
1068 * A localisation cache optimised for loading large amounts of data for many
1069 * languages. Used by rebuildLocalisationCache.php.
1070 */
1071 class LocalisationCache_BulkLoad extends LocalisationCache {
1072 /**
1073 * A cache of the contents of data files.
1074 * Core files are serialized to avoid using ~1GB of RAM during a recache.
1075 */
1076 var $fileCache = array();
1077
1078 /**
1079 * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1080 * to keep the most recently used language codes at the end of the array, and
1081 * the language codes that are ready to be deleted at the beginning.
1082 */
1083 var $mruLangs = array();
1084
1085 /**
1086 * Maximum number of languages that may be loaded into $this->data
1087 */
1088 var $maxLoadedLangs = 10;
1089
1090 /**
1091 * @param $fileName
1092 * @param $fileType
1093 * @return array|mixed
1094 */
1095 protected function readPHPFile( $fileName, $fileType ) {
1096 $serialize = $fileType === 'core';
1097 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1098 $data = parent::readPHPFile( $fileName, $fileType );
1099
1100 if ( $serialize ) {
1101 $encData = serialize( $data );
1102 } else {
1103 $encData = $data;
1104 }
1105
1106 $this->fileCache[$fileName][$fileType] = $encData;
1107
1108 return $data;
1109 } elseif ( $serialize ) {
1110 return unserialize( $this->fileCache[$fileName][$fileType] );
1111 } else {
1112 return $this->fileCache[$fileName][$fileType];
1113 }
1114 }
1115
1116 /**
1117 * @param $code
1118 * @param $key
1119 * @return mixed
1120 */
1121 public function getItem( $code, $key ) {
1122 unset( $this->mruLangs[$code] );
1123 $this->mruLangs[$code] = true;
1124 return parent::getItem( $code, $key );
1125 }
1126
1127 /**
1128 * @param $code
1129 * @param $key
1130 * @param $subkey
1131 * @return
1132 */
1133 public function getSubitem( $code, $key, $subkey ) {
1134 unset( $this->mruLangs[$code] );
1135 $this->mruLangs[$code] = true;
1136 return parent::getSubitem( $code, $key, $subkey );
1137 }
1138
1139 /**
1140 * @param $code
1141 */
1142 public function recache( $code ) {
1143 parent::recache( $code );
1144 unset( $this->mruLangs[$code] );
1145 $this->mruLangs[$code] = true;
1146 $this->trimCache();
1147 }
1148
1149 /**
1150 * @param $code
1151 */
1152 public function unload( $code ) {
1153 unset( $this->mruLangs[$code] );
1154 parent::unload( $code );
1155 }
1156
1157 /**
1158 * Unload cached languages until there are less than $this->maxLoadedLangs
1159 */
1160 protected function trimCache() {
1161 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1162 reset( $this->mruLangs );
1163 $code = key( $this->mruLangs );
1164 wfDebug( __METHOD__.": unloading $code\n" );
1165 $this->unload( $code );
1166 }
1167 }
1168 }