includes/cache/MessageCache.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup Cache
   5  */
   6
   7 /**
   8  *
   9  */
  10 define( 'MSG_LOAD_TIMEOUT', 60 );
  11 define( 'MSG_LOCK_TIMEOUT', 10 );
  12 define( 'MSG_WAIT_TIMEOUT', 10 );
  13 define( 'MSG_CACHE_VERSION', 1 );
  14
  15 /**
  16  * Message cache
  17  * Performs various MediaWiki namespace-related functions
  18  * @ingroup Cache
  19  */
  20 class MessageCache {
  21         /**
  22          * Process local cache of loaded messages that are defined in
  23          * MediaWiki namespace. First array level is a language code,
  24          * second level is message key and the values are either message
  25          * content prefixed with space, or !NONEXISTENT for negative
  26          * caching.
  27          */
  28         protected $mCache;
  29
  30         // Should  mean that database cannot be used, but check
  31         protected $mDisable;
  32
  33         /// Lifetime for cache, used by object caching
  34         protected $mExpiry;
  35
  36         /**
  37          * Message cache has it's own parser which it uses to transform
  38          * messages.
  39          */
  40         protected $mParserOptions, $mParser;
  41
  42         /// Variable for tracking which variables are already loaded
  43         protected $mLoadedLanguages = array();
  44
  45         /**
  46          * Used for automatic detection of most used messages.
  47          */
  48         protected $mRequestedMessages = array();
  49
  50         /**
  51          * How long the message request counts are stored. Longer period gives
  52          * better sample, but also takes longer to adapt changes. The counts
  53          * are aggregrated per day, regardless of the value of this variable.
  54          */
  55         protected static $mAdaptiveDataAge = 604800; // Is 7*24*3600
  56
  57         /**
  58          * Filter the tail of less used messages that are requested more seldom
  59          * than this factor times the number of request of most requested message.
  60          * These messages are not loaded in the default set, but are still cached
  61          * individually on demand with the normal cache expiry time.
  62          */
  63         protected static $mAdaptiveInclusionThreshold = 0.05;
  64
  65         /**
  66          * Singleton instance
  67          *
  68          * @var MessageCache
  69          */
  70         private static $instance;
  71
  72         /**
  73          * @var bool
  74          */
  75         protected $mInParser = false;
  76
  77         /**
  78          * Get the signleton instance of this class
  79          *
  80          * @since 1.18
  81          * @return MessageCache object
  82          */
  83         public static function singleton() {
  84                 if ( is_null( self::$instance ) ) {
  85                         global $wgUseDatabaseMessages, $wgMsgCacheExpiry;
  86                         self::$instance = new self( wfGetMessageCacheStorage(), $wgUseDatabaseMessages, $wgMsgCacheExpiry );
  87                 }
  88                 return self::$instance;
  89         }
  90
  91         /**
  92          * Destroy the singleton instance
  93          *
  94          * @since 1.18
  95          */
  96         public static function destroyInstance() {
  97                 self::$instance = null;
  98         }
  99
 100         function __construct( $memCached, $useDB, $expiry ) {
 101                 if ( !$memCached ) {
 102                         $memCached = wfGetCache( CACHE_NONE );
 103                 }
 104
 105                 $this->mMemc = $memCached;
 106                 $this->mDisable = !$useDB;
 107                 $this->mExpiry = $expiry;
 108         }
 109
 110         /**
 111          * ParserOptions is lazy initialised.
 112          *
 113          * @return ParserOptions
 114          */
 115         function getParserOptions() {
 116                 if ( !$this->mParserOptions ) {
 117                         $this->mParserOptions = new ParserOptions;
 118                 }
 119                 return $this->mParserOptions;
 120         }
 121
 122         /**
 123          * Try to load the cache from a local file.
 124          * Actual format of the file depends on the $wgLocalMessageCacheSerialized
 125          * setting.
 126          *
 127          * @param $hash String: the hash of contents, to check validity.
 128          * @param $code Mixed: Optional language code, see documenation of load().
 129          * @return false on failure.
 130          */
 131         function loadFromLocal( $hash, $code ) {
 132                 global $wgCacheDirectory, $wgLocalMessageCacheSerialized;
 133
 134                 $filename = "$wgCacheDirectory/messages-" . wfWikiID() . "-$code";
 135
 136                 # Check file existence
 137                 wfSuppressWarnings();
 138                 $file = fopen( $filename, 'r' );
 139                 wfRestoreWarnings();
 140                 if ( !$file ) {
 141                         return false; // No cache file
 142                 }
 143
 144                 if ( $wgLocalMessageCacheSerialized ) {
 145                         // Check to see if the file has the hash specified
 146                         $localHash = fread( $file, 32 );
 147                         if ( $hash === $localHash ) {
 148                                 // All good, get the rest of it
 149                                 $serialized = '';
 150                                 while ( !feof( $file ) ) {
 151                                         $serialized .= fread( $file, 100000 );
 152                                 }
 153                                 fclose( $file );
 154                                 return $this->setCache( unserialize( $serialized ), $code );
 155                         } else {
 156                                 fclose( $file );
 157                                 return false; // Wrong hash
 158                         }
 159                 } else {
 160                         $localHash = substr( fread( $file, 40 ), 8 );
 161                         fclose( $file );
 162                         if ( $hash != $localHash ) {
 163                                 return false; // Wrong hash
 164                         }
 165
 166                         # Require overwrites the member variable or just shadows it?
 167                         require( $filename );
 168                         return $this->setCache( $this->mCache, $code );
 169                 }
 170         }
 171
 172         /**
 173          * Save the cache to a local file.
 174          */
 175         function saveToLocal( $serialized, $hash, $code ) {
 176                 global $wgCacheDirectory;
 177
 178                 $filename = "$wgCacheDirectory/messages-" . wfWikiID() . "-$code";
 179                 wfMkdirParents( $wgCacheDirectory ); // might fail
 180
 181                 wfSuppressWarnings();
 182                 $file = fopen( $filename, 'w' );
 183                 wfRestoreWarnings();
 184
 185                 if ( !$file ) {
 186                         wfDebug( "Unable to open local cache file for writing\n" );
 187                         return;
 188                 }
 189
 190                 fwrite( $file, $hash . $serialized );
 191                 fclose( $file );
 192                 @chmod( $filename, 0666 );
 193         }
 194
 195         function saveToScript( $array, $hash, $code ) {
 196                 global $wgCacheDirectory;
 197
 198                 $filename = "$wgCacheDirectory/messages-" . wfWikiID() . "-$code";
 199                 $tempFilename = $filename . '.tmp';
 200                 wfMkdirParents( $wgCacheDirectory ); // might fail
 201
 202                 wfSuppressWarnings();
 203                 $file = fopen( $tempFilename, 'w' );
 204                 wfRestoreWarnings();
 205
 206                 if ( !$file ) {
 207                         wfDebug( "Unable to open local cache file for writing\n" );
 208                         return;
 209                 }
 210
 211                 fwrite( $file, "<?php\n//$hash\n\n \$this->mCache = array(" );
 212
 213                 foreach ( $array as $key => $message ) {
 214                         $key = $this->escapeForScript( $key );
 215                         $message = $this->escapeForScript( $message );
 216                         fwrite( $file, "'$key' => '$message',\n" );
 217                 }
 218
 219                 fwrite( $file, ");\n?>" );
 220                 fclose( $file);
 221                 rename( $tempFilename, $filename );
 222         }
 223
 224         function escapeForScript( $string ) {
 225                 $string = str_replace( '\\', '\\\\', $string );
 226                 $string = str_replace( '\'', '\\\'', $string );
 227                 return $string;
 228         }
 229
 230         /**
 231          * Set the cache to $cache, if it is valid. Otherwise set the cache to false.
 232          *
 233          * @return bool
 234          */
 235         function setCache( $cache, $code ) {
 236                 if ( isset( $cache['VERSION'] ) && $cache['VERSION'] == MSG_CACHE_VERSION ) {
 237                         $this->mCache[$code] = $cache;
 238                         return true;
 239                 } else {
 240                         return false;
 241                 }
 242         }
 243
 244         /**
 245          * Loads messages from caches or from database in this order:
 246          * (1) local message cache (if $wgUseLocalMessageCache is enabled)
 247          * (2) memcached
 248          * (3) from the database.
 249          *
 250          * When succesfully loading from (2) or (3), all higher level caches are
 251          * updated for the newest version.
 252          *
 253          * Nothing is loaded if member variable mDisable is true, either manually
 254          * set by calling code or if message loading fails (is this possible?).
 255          *
 256          * Returns true if cache is already populated or it was succesfully populated,
 257          * or false if populating empty cache fails. Also returns true if MessageCache
 258          * is disabled.
 259          *
 260          * @param $code String: language to which load messages
 261          */
 262         function load( $code = false ) {
 263                 global $wgUseLocalMessageCache;
 264
 265                 if( !is_string( $code ) ) {
 266                         # This isn't really nice, so at least make a note about it and try to
 267                         # fall back
 268                         wfDebug( __METHOD__ . " called without providing a language code\n" );
 269                         $code = 'en';
 270                 }
 271
 272                 # Don't do double loading...
 273                 if ( isset( $this->mLoadedLanguages[$code] ) ) {
 274                         return true;
 275                 }
 276
 277                 # 8 lines of code just to say (once) that message cache is disabled
 278                 if ( $this->mDisable ) {
 279                         static $shownDisabled = false;
 280                         if ( !$shownDisabled ) {
 281                                 wfDebug( __METHOD__ . ": disabled\n" );
 282                                 $shownDisabled = true;
 283                         }
 284                         return true;
 285                 }
 286
 287                 # Loading code starts
 288                 wfProfileIn( __METHOD__ );
 289                 $success = false; # Keep track of success
 290                 $where = array(); # Debug info, delayed to avoid spamming debug log too much
 291                 $cacheKey = wfMemcKey( 'messages', $code ); # Key in memc for messages
 292
 293                 # (1) local cache
 294                 # Hash of the contents is stored in memcache, to detect if local cache goes
 295                 # out of date (due to update in other thread?)
 296                 if ( $wgUseLocalMessageCache ) {
 297                         wfProfileIn( __METHOD__ . '-fromlocal' );
 298
 299                         $hash = $this->mMemc->get( wfMemcKey( 'messages', $code, 'hash' ) );
 300                         if ( $hash ) {
 301                                 $success = $this->loadFromLocal( $hash, $code );
 302                                 if ( $success ) $where[] = 'got from local cache';
 303                         }
 304                         wfProfileOut( __METHOD__ . '-fromlocal' );
 305                 }
 306
 307                 # (2) memcache
 308                 # Fails if nothing in cache, or in the wrong version.
 309                 if ( !$success ) {
 310                         wfProfileIn( __METHOD__ . '-fromcache' );
 311                         $cache = $this->mMemc->get( $cacheKey );
 312                         $success = $this->setCache( $cache, $code );
 313                         if ( $success ) {
 314                                 $where[] = 'got from global cache';
 315                                 $this->saveToCaches( $cache, false, $code );
 316                         }
 317                         wfProfileOut( __METHOD__ . '-fromcache' );
 318                 }
 319
 320                 # (3)
 321                 # Nothing in caches... so we need create one and store it in caches
 322                 if ( !$success ) {
 323                         $where[] = 'cache is empty';
 324                         $where[] = 'loading from database';
 325
 326                         $this->lock( $cacheKey );
 327
 328                         # Limit the concurrency of loadFromDB to a single process
 329                         # This prevents the site from going down when the cache expires
 330                         $statusKey = wfMemcKey( 'messages', $code, 'status' );
 331                         $success = $this->mMemc->add( $statusKey, 'loading', MSG_LOAD_TIMEOUT );
 332                         if ( $success ) {
 333                                 $cache = $this->loadFromDB( $code );
 334                                 $success = $this->setCache( $cache, $code );
 335                         }
 336                         if ( $success ) {
 337                                 $success = $this->saveToCaches( $cache, true, $code );
 338                                 if ( $success ) {
 339                                         $this->mMemc->delete( $statusKey );
 340                                 } else {
 341                                         $this->mMemc->set( $statusKey, 'error', 60 * 5 );
 342                                         wfDebug( "MemCached set error in MessageCache: restart memcached server!\n" );
 343                                 }
 344                         }
 345                         $this->unlock($cacheKey);
 346                 }
 347
 348                 if ( !$success ) {
 349                         # Bad luck... this should not happen
 350                         $where[] = 'loading FAILED - cache is disabled';
 351                         $info = implode( ', ', $where );
 352                         wfDebug( __METHOD__ . ": Loading $code... $info\n" );
 353                         $this->mDisable = true;
 354                         $this->mCache = false;
 355                 } else {
 356                         # All good, just record the success
 357                         $info = implode( ', ', $where );
 358                         wfDebug( __METHOD__ . ": Loading $code... $info\n" );
 359                         $this->mLoadedLanguages[$code] = true;
 360                 }
 361                 wfProfileOut( __METHOD__ );
 362                 return $success;
 363         }
 364
 365         /**
 366          * Loads cacheable messages from the database. Messages bigger than
 367          * $wgMaxMsgCacheEntrySize are assigned a special value, and are loaded
 368          * on-demand from the database later.
 369          *
 370          * @param $code String: language code.
 371          * @return Array: loaded messages for storing in caches.
 372          */
 373         function loadFromDB( $code ) {
 374                 wfProfileIn( __METHOD__ );
 375                 global $wgMaxMsgCacheEntrySize, $wgLanguageCode, $wgAdaptiveMessageCache;
 376                 $dbr = wfGetDB( DB_SLAVE );
 377                 $cache = array();
 378
 379                 # Common conditions
 380                 $conds = array(
 381                         'page_is_redirect' => 0,
 382                         'page_namespace' => NS_MEDIAWIKI,
 383                 );
 384
 385                 $mostused = array();
 386                 if ( $wgAdaptiveMessageCache ) {
 387                         $mostused = $this->getMostUsedMessages();
 388                         if ( $code !== $wgLanguageCode ) {
 389                                 foreach ( $mostused as $key => $value ) {
 390                                         $mostused[$key] = "$value/$code";
 391                                 }
 392                         }
 393                 }
 394
 395                 if ( count( $mostused ) ) {
 396                         $conds['page_title'] = $mostused;
 397                 } elseif ( $code !== $wgLanguageCode ) {
 398                         $conds[] = 'page_title' . $dbr->buildLike( $dbr->anyString(), "/$code" );
 399                 } else {
 400                         # Effectively disallows use of '/' character in NS_MEDIAWIKI for uses
 401                         # other than language code.
 402                         $conds[] = 'page_title NOT' . $dbr->buildLike( $dbr->anyString(), '/', $dbr->anyString() );
 403                 }
 404
 405                 # Conditions to fetch oversized pages to ignore them
 406                 $bigConds = $conds;
 407                 $bigConds[] = 'page_len > ' . intval( $wgMaxMsgCacheEntrySize );
 408
 409                 # Load titles for all oversized pages in the MediaWiki namespace
 410                 $res = $dbr->select( 'page', 'page_title', $bigConds, __METHOD__ . "($code)-big" );
 411                 foreach ( $res as $row ) {
 412                         $cache[$row->page_title] = '!TOO BIG';
 413                 }
 414
 415                 # Conditions to load the remaining pages with their contents
 416                 $smallConds = $conds;
 417                 $smallConds[] = 'page_latest=rev_id';
 418                 $smallConds[] = 'rev_text_id=old_id';
 419                 $smallConds[] = 'page_len <= ' . intval( $wgMaxMsgCacheEntrySize );
 420
 421                 $res = $dbr->select(
 422                         array( 'page', 'revision', 'text' ),
 423                         array( 'page_title', 'old_text', 'old_flags' ),
 424                         $smallConds,
 425                         __METHOD__ . "($code)-small"
 426                 );
 427
 428                 foreach ( $res as $row ) {
 429                         $cache[$row->page_title] = ' ' . Revision::getRevisionText( $row );
 430                 }
 431
 432                 foreach ( $mostused as $key ) {
 433                         if ( !isset( $cache[$key] ) ) {
 434                                 $cache[$key] = '!NONEXISTENT';
 435                         }
 436                 }
 437
 438                 $cache['VERSION'] = MSG_CACHE_VERSION;
 439                 wfProfileOut( __METHOD__ );
 440                 return $cache;
 441         }
 442
 443         /**
 444          * Updates cache as necessary when message page is changed
 445          *
 446          * @param $title String: name of the page changed.
 447          * @param $text Mixed: new contents of the page.
 448          */
 449         public function replace( $title, $text ) {
 450                 global $wgMaxMsgCacheEntrySize;
 451                 wfProfileIn( __METHOD__ );
 452
 453                 if ( $this->mDisable ) {
 454                         wfProfileOut( __METHOD__ );
 455                         return;
 456                 }
 457
 458                 list( $msg, $code ) = $this->figureMessage( $title );
 459
 460                 $cacheKey = wfMemcKey( 'messages', $code );
 461                 $this->load( $code );
 462                 $this->lock( $cacheKey );
 463
 464                 $titleKey = wfMemcKey( 'messages', 'individual', $title );
 465
 466                 if ( $text === false ) {
 467                         # Article was deleted
 468                         $this->mCache[$code][$title] = '!NONEXISTENT';
 469                         $this->mMemc->delete( $titleKey );
 470                 } elseif ( strlen( $text ) > $wgMaxMsgCacheEntrySize ) {
 471                         # Check for size
 472                         $this->mCache[$code][$title] = '!TOO BIG';
 473                         $this->mMemc->set( $titleKey, ' ' . $text, $this->mExpiry );
 474                 } else {
 475                         $this->mCache[$code][$title] = ' ' . $text;
 476                         $this->mMemc->delete( $titleKey );
 477                 }
 478
 479                 # Update caches
 480                 $this->saveToCaches( $this->mCache[$code], true, $code );
 481                 $this->unlock( $cacheKey );
 482
 483                 // Also delete cached sidebar... just in case it is affected
 484                 $codes = array( $code );
 485                 if ( $code === 'en'  ) {
 486                         // Delete all sidebars, like for example on action=purge on the
 487                         // sidebar messages
 488                         $codes = array_keys( Language::getLanguageNames() );
 489                 }
 490
 491                 global $parserMemc;
 492                 foreach ( $codes as $code ) {
 493                         $sidebarKey = wfMemcKey( 'sidebar', $code );
 494                         $parserMemc->delete( $sidebarKey );
 495                 }
 496
 497                 // Update the message in the message blob store
 498                 global $wgContLang;
 499                 MessageBlobStore::updateMessage( $wgContLang->lcfirst( $msg ) );
 500
 501                 wfRunHooks( 'MessageCacheReplace', array( $title, $text ) );
 502
 503                 wfProfileOut( __METHOD__ );
 504         }
 505
 506         /**
 507          * Shortcut to update caches.
 508          *
 509          * @param $cache Array: cached messages with a version.
 510          * @param $memc Bool: Wether to update or not memcache.
 511          * @param $code String: Language code.
 512          * @return False on somekind of error.
 513          */
 514         protected function saveToCaches( $cache, $memc = true, $code = false ) {
 515                 wfProfileIn( __METHOD__ );
 516                 global $wgUseLocalMessageCache, $wgLocalMessageCacheSerialized;
 517
 518                 $cacheKey = wfMemcKey( 'messages', $code );
 519
 520                 if ( $memc ) {
 521                         $success = $this->mMemc->set( $cacheKey, $cache, $this->mExpiry );
 522                 } else {
 523                         $success = true;
 524                 }
 525
 526                 # Save to local cache
 527                 if ( $wgUseLocalMessageCache ) {
 528                         $serialized = serialize( $cache );
 529                         $hash = md5( $serialized );
 530                         $this->mMemc->set( wfMemcKey( 'messages', $code, 'hash' ), $hash, $this->mExpiry );
 531                         if ($wgLocalMessageCacheSerialized) {
 532                                 $this->saveToLocal( $serialized, $hash, $code );
 533                         } else {
 534                                 $this->saveToScript( $cache, $hash, $code );
 535                         }
 536                 }
 537
 538                 wfProfileOut( __METHOD__ );
 539                 return $success;
 540         }
 541
 542         /**
 543          * Represents a write lock on the messages key
 544          *
 545          * @return Boolean: success
 546          */
 547         function lock( $key ) {
 548                 $lockKey = $key . ':lock';
 549                 for ( $i = 0; $i < MSG_WAIT_TIMEOUT && !$this->mMemc->add( $lockKey, 1, MSG_LOCK_TIMEOUT ); $i++ ) {
 550                         sleep( 1 );
 551                 }
 552
 553                 return $i >= MSG_WAIT_TIMEOUT;
 554         }
 555
 556         function unlock( $key ) {
 557                 $lockKey = $key . ':lock';
 558                 $this->mMemc->delete( $lockKey );
 559         }
 560
 561         /**
 562          * Get a message from either the content language or the user language.
 563          *
 564          * @param $key String: the message cache key
 565          * @param $useDB Boolean: get the message from the DB, false to use only
 566          *               the localisation
 567          * @param $langcode String: code of the language to get the message for, if
 568          *                  it is a valid code create a language for that language,
 569          *                  if it is a string but not a valid code then make a basic
 570          *                  language object, if it is a false boolean then use the
 571          *                  current users language (as a fallback for the old
 572          *                  parameter functionality), or if it is a true boolean
 573          *                  then use the wikis content language (also as a
 574          *                  fallback).
 575          * @param $isFullKey Boolean: specifies whether $key is a two part key
 576          *                   "msg/lang".
 577          */
 578         function get( $key, $useDB = true, $langcode = true, $isFullKey = false ) {
 579                 global $wgLanguageCode, $wgContLang;
 580
 581                 if ( !is_string( $key ) ) {
 582                         throw new MWException( 'Non-string key given' );
 583                 }
 584
 585                 if ( strval( $key ) === '' ) {
 586                         # Shortcut: the empty key is always missing
 587                         return false;
 588                 }
 589
 590                 $lang = wfGetLangObj( $langcode );
 591                 if ( !$lang ) {
 592                         throw new MWException( "Bad lang code $langcode given" );
 593                 }
 594
 595                 $langcode = $lang->getCode();
 596
 597                 $message = false;
 598
 599                 # Normalise title-case input (with some inlining)
 600                 $lckey = str_replace( ' ', '_', $key );
 601                 if ( ord( $key ) < 128 ) {
 602                         $lckey[0] = strtolower( $lckey[0] );
 603                         $uckey = ucfirst( $lckey );
 604                 } else {
 605                         $lckey = $wgContLang->lcfirst( $lckey );
 606                         $uckey = $wgContLang->ucfirst( $lckey );
 607                 }
 608
 609                 /**
 610                  * Record each message request, but only once per request.
 611                  * This information is not used unless $wgAdaptiveMessageCache
 612                  * is enabled.
 613                  */
 614                 $this->mRequestedMessages[$uckey] = true;
 615
 616                 # Try the MediaWiki namespace
 617                 if( !$this->mDisable && $useDB ) {
 618                         $title = $uckey;
 619                         if( !$isFullKey && ( $langcode != $wgLanguageCode ) ) {
 620                                 $title .= '/' . $langcode;
 621                         }
 622                         $message = $this->getMsgFromNamespace( $title, $langcode );
 623                 }
 624
 625                 # Try the array in the language object
 626                 if ( $message === false ) {
 627                         $message = $lang->getMessage( $lckey );
 628                         if ( is_null( $message ) ) {
 629                                 $message = false;
 630                         }
 631                 }
 632
 633                 # Try the array of another language
 634                 if( $message === false ) {
 635                         $parts = explode( '/', $lckey );
 636                         # We may get calls for things that are http-urls from sidebar
 637                         # Let's not load nonexistent languages for those
 638                         # They usually have more than one slash.
 639                         if ( count( $parts ) == 2 && $parts[1] !== '' ) {
 640                                 $message = Language::getMessageFor( $parts[0], $parts[1] );
 641                                 if ( is_null( $message ) ) {
 642                                         $message = false;
 643                                 }
 644                         }
 645                 }
 646
 647                 # Is this a custom message? Try the default language in the db...
 648                 if( ( $message === false || $message === '-' ) &&
 649                         !$this->mDisable && $useDB &&
 650                         !$isFullKey && ( $langcode != $wgLanguageCode ) ) {
 651                         $message = $this->getMsgFromNamespace( $uckey, $wgLanguageCode );
 652                 }
 653
 654                 # Final fallback
 655                 if( $message === false ) {
 656                         return false;
 657                 }
 658
 659                 # Fix whitespace
 660                 $message = strtr( $message,
 661                         array(
 662                                 # Fix for trailing whitespace, removed by textarea
 663                                 '&#32;' => ' ',
 664                                 # Fix for NBSP, converted to space by firefox
 665                                 '&nbsp;' => "\xc2\xa0",
 666                                 '&#160;' => "\xc2\xa0",
 667                         ) );
 668
 669                 return $message;
 670         }
 671
 672         /**
 673          * Get a message from the MediaWiki namespace, with caching. The key must
 674          * first be converted to two-part lang/msg form if necessary.
 675          *
 676          * @param $title String: Message cache key with initial uppercase letter.
 677          * @param $code String: code denoting the language to try.
 678          */
 679         function getMsgFromNamespace( $title, $code ) {
 680                 global $wgAdaptiveMessageCache;
 681
 682                 $this->load( $code );
 683                 if ( isset( $this->mCache[$code][$title] ) ) {
 684                         $entry = $this->mCache[$code][$title];
 685                         if ( substr( $entry, 0, 1 ) === ' ' ) {
 686                                 return substr( $entry, 1 );
 687                         } elseif ( $entry === '!NONEXISTENT' ) {
 688                                 return false;
 689                         } elseif( $entry === '!TOO BIG' ) {
 690                                 // Fall through and try invididual message cache below
 691                         }
 692                 } else {
 693                         // XXX: This is not cached in process cache, should it?
 694                         $message = false;
 695                         wfRunHooks( 'MessagesPreLoad', array( $title, &$message ) );
 696                         if ( $message !== false ) {
 697                                 return $message;
 698                         }
 699
 700                         /**
 701                          * If message cache is in normal mode, it is guaranteed
 702                          * (except bugs) that there is always entry (or placeholder)
 703                          * in the cache if message exists. Thus we can do minor
 704                          * performance improvement and return false early.
 705                          */
 706                         if ( !$wgAdaptiveMessageCache ) {
 707                                 return false;
 708                         }
 709                 }
 710
 711                 # Try the individual message cache
 712                 $titleKey = wfMemcKey( 'messages', 'individual', $title );
 713                 $entry = $this->mMemc->get( $titleKey );
 714                 if ( $entry ) {
 715                         if ( substr( $entry, 0, 1 ) === ' ' ) {
 716                                 $this->mCache[$code][$title] = $entry;
 717                                 return substr( $entry, 1 );
 718                         } elseif ( $entry === '!NONEXISTENT' ) {
 719                                 $this->mCache[$code][$title] = '!NONEXISTENT';
 720                                 return false;
 721                         } else {
 722                                 # Corrupt/obsolete entry, delete it
 723                                 $this->mMemc->delete( $titleKey );
 724                         }
 725                 }
 726
 727                 # Try loading it from the database
 728                 $revision = Revision::newFromTitle( Title::makeTitle( NS_MEDIAWIKI, $title ) );
 729                 if ( $revision ) {
 730                         $message = $revision->getText();
 731                         $this->mCache[$code][$title] = ' ' . $message;
 732                         $this->mMemc->set( $titleKey, ' ' . $message, $this->mExpiry );
 733                 } else {
 734                         $message = false;
 735                         $this->mCache[$code][$title] = '!NONEXISTENT';
 736                         $this->mMemc->set( $titleKey, '!NONEXISTENT', $this->mExpiry );
 737                 }
 738
 739                 return $message;
 740         }
 741
 742         /**
 743          * @param $message string
 744          * @param $interface bool
 745          * @param $language
 746          * @param $title Title
 747          * @return string
 748          */
 749         function transform( $message, $interface = false, $language = null, $title = null ) {
 750                 // Avoid creating parser if nothing to transform
 751                 if( strpos( $message, '{{' ) === false ) {
 752                         return $message;
 753                 }
 754
 755                 if ( $this->mInParser ) {
 756                         return $message;
 757                 }
 758
 759                 $parser = $this->getParser();
 760                 if ( $parser ) {
 761                         $popts = $this->getParserOptions();
 762                         $popts->setInterfaceMessage( $interface );
 763                         $popts->setTargetLanguage( $language );
 764
 765                         $userlang = $popts->setUserLang( $language );
 766                         $this->mInParser = true;
 767                         $message = $parser->transformMsg( $message, $popts, $title );
 768                         $this->mInParser = false;
 769                         $popts->setUserLang( $userlang );
 770                 }
 771                 return $message;
 772         }
 773
 774         /**
 775          * @return Parser
 776          */
 777         function getParser() {
 778                 global $wgParser, $wgParserConf;
 779                 if ( !$this->mParser && isset( $wgParser ) ) {
 780                         # Do some initialisation so that we don't have to do it twice
 781                         $wgParser->firstCallInit();
 782                         # Clone it and store it
 783                         $class = $wgParserConf['class'];
 784                         if ( $class == 'Parser_DiffTest' ) {
 785                                 # Uncloneable
 786                                 $this->mParser = new $class( $wgParserConf );
 787                         } else {
 788                                 $this->mParser = clone $wgParser;
 789                         }
 790                 }
 791                 return $this->mParser;
 792         }
 793
 794         /**
 795          * @param $text string
 796          * @param $string Title|string
 797          * @param $title Title
 798          * @param $interface bool
 799          * @param $linestart bool
 800          * @param $language
 801          * @return ParserOutput
 802          */
 803         public function parse( $text, $title = null, $linestart = true, $interface = false, $language = null  ) {
 804                 if ( $this->mInParser ) {
 805                         return htmlspecialchars( $text );
 806                 }
 807
 808                 $parser = $this->getParser();
 809                 $popts = $this->getParserOptions();
 810
 811                 if ( $interface ) {
 812                         $popts->setInterfaceMessage( true );
 813                 }
 814                 if ( $language !== null ) {
 815                         $popts->setTargetLanguage( $language );
 816                 }
 817
 818                 if ( !$title || !$title instanceof Title ) {
 819                         global $wgTitle;
 820                         $title = $wgTitle;
 821                 }
 822
 823                 $this->mInParser = true;
 824                 $res = $parser->parse( $text, $title, $popts, $linestart );
 825                 $this->mInParser = false;
 826
 827                 return $res;
 828         }
 829
 830         function disable() {
 831                 $this->mDisable = true;
 832         }
 833
 834         function enable() {
 835                 $this->mDisable = false;
 836         }
 837
 838         /**
 839          * Clear all stored messages. Mainly used after a mass rebuild.
 840          */
 841         function clear() {
 842                 $langs = Language::getLanguageNames( false );
 843                 foreach ( array_keys($langs) as $code ) {
 844                         # Global cache
 845                         $this->mMemc->delete( wfMemcKey( 'messages', $code ) );
 846                         # Invalidate all local caches
 847                         $this->mMemc->delete( wfMemcKey( 'messages', $code, 'hash' ) );
 848                 }
 849                 $this->mLoadedLanguages = array();
 850         }
 851
 852         public function figureMessage( $key ) {
 853                 global $wgLanguageCode;
 854                 $pieces = explode( '/', $key );
 855                 if( count( $pieces ) < 2 ) {
 856                         return array( $key, $wgLanguageCode );
 857                 }
 858
 859                 $lang = array_pop( $pieces );
 860                 $validCodes = Language::getLanguageNames();
 861                 if( !array_key_exists( $lang, $validCodes ) ) {
 862                         return array( $key, $wgLanguageCode );
 863                 }
 864
 865                 $message = implode( '/', $pieces );
 866                 return array( $message, $lang );
 867         }
 868
 869         public static function logMessages() {
 870                 wfProfileIn( __METHOD__ );
 871                 global $wgAdaptiveMessageCache;
 872                 if ( !$wgAdaptiveMessageCache || !self::$instance instanceof MessageCache ) {
 873                         wfProfileOut( __METHOD__ );
 874                         return;
 875                 }
 876
 877                 $cachekey = wfMemckey( 'message-profiling' );
 878                 $cache = wfGetCache( CACHE_DB );
 879                 $data = $cache->get( $cachekey );
 880
 881                 if ( !$data ) {
 882                         $data = array();
 883                 }
 884
 885                 $age = self::$mAdaptiveDataAge;
 886                 $filterDate = substr( wfTimestamp( TS_MW, time() - $age ), 0, 8 );
 887                 foreach ( array_keys( $data ) as $key ) {
 888                         if ( $key < $filterDate ) {
 889                                 unset( $data[$key] );
 890                         }
 891                 }
 892
 893                 $index = substr( wfTimestampNow(), 0, 8 );
 894                 if ( !isset( $data[$index] ) ) {
 895                         $data[$index] = array();
 896                 }
 897
 898                 foreach ( self::$instance->mRequestedMessages as $message => $_ ) {
 899                         if ( !isset( $data[$index][$message] ) ) {
 900                                 $data[$index][$message] = 0;
 901                         }
 902                         $data[$index][$message]++;
 903                 }
 904
 905                 $cache->set( $cachekey, $data );
 906                 wfProfileOut( __METHOD__ );
 907         }
 908
 909         public function getMostUsedMessages() {
 910                 wfProfileIn( __METHOD__ );
 911                 $cachekey = wfMemcKey( 'message-profiling' );
 912                 $cache = wfGetCache( CACHE_DB );
 913                 $data = $cache->get( $cachekey );
 914                 if ( !$data ) {
 915                         wfProfileOut( __METHOD__ );
 916                         return array();
 917                 }
 918
 919                 $list = array();
 920
 921                 foreach( $data as $messages ) {
 922                         foreach( $messages as $message => $count ) {
 923                                 $key = $message;
 924                                 if ( !isset( $list[$key] ) ) {
 925                                         $list[$key] = 0;
 926                                 }
 927                                 $list[$key] += $count;
 928                         }
 929                 }
 930
 931                 $max = max( $list );
 932                 foreach ( $list as $message => $count ) {
 933                         if ( $count < intval( $max * self::$mAdaptiveInclusionThreshold ) ) {
 934                                 unset( $list[$message] );
 935                         }
 936                 }
 937
 938                 wfProfileOut( __METHOD__ );
 939                 return array_keys( $list );
 940         }
 941
 942 }