includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @author Roan Kattouw
  20  * @author Trevor Parscal
  21  */
  22
  23 /**
  24  * Dynamic JavaScript and CSS resource loading system.
  25  *
  26  * Most of the documention is on the MediaWiki documentation wiki starting at:
  27  *    http://www.mediawiki.org/wiki/ResourceLoader
  28  */
  29 class ResourceLoader {
  30
  31         /* Protected Static Members */
  32         protected static $filterCacheVersion = 5;
  33         protected static $requiredSourceProperties = array( 'loadScript' );
  34
  35         /** Array: List of module name/ResourceLoaderModule object pairs */
  36         protected $modules = array();
  37
  38         /** Associative array mapping module name to info associative array */
  39         protected $moduleInfos = array();
  40
  41         /** array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) **/
  42         protected $sources = array();
  43
  44         /* Protected Methods */
  45
  46         /**
  47          * Loads information stored in the database about modules.
  48          *
  49          * This method grabs modules dependencies from the database and updates modules
  50          * objects.
  51          *
  52          * This is not inside the module code because it is much faster to
  53          * request all of the information at once than it is to have each module
  54          * requests its own information. This sacrifice of modularity yields a substantial
  55          * performance improvement.
  56          *
  57          * @param $modules Array: List of module names to preload information for
  58          * @param $context ResourceLoaderContext: Context to load the information within
  59          */
  60         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  61                 if ( !count( $modules ) ) {
  62                         return; // or else Database*::select() will explode, plus it's cheaper!
  63                 }
  64                 $dbr = wfGetDB( DB_SLAVE );
  65                 $skin = $context->getSkin();
  66                 $lang = $context->getLanguage();
  67
  68                 // Get file dependency information
  69                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  70                                 'md_module' => $modules,
  71                                 'md_skin' => $skin
  72                         ), __METHOD__
  73                 );
  74
  75                 // Set modules' dependencies
  76                 $modulesWithDeps = array();
  77                 foreach ( $res as $row ) {
  78                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  79                                 FormatJson::decode( $row->md_deps, true )
  80                         );
  81                         $modulesWithDeps[] = $row->md_module;
  82                 }
  83
  84                 // Register the absence of a dependency row too
  85                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  86                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  87                 }
  88
  89                 // Get message blob mtimes. Only do this for modules with messages
  90                 $modulesWithMessages = array();
  91                 foreach ( $modules as $name ) {
  92                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  93                                 $modulesWithMessages[] = $name;
  94                         }
  95                 }
  96                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
  97                 if ( count( $modulesWithMessages ) ) {
  98                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
  99                                         'mr_resource' => $modulesWithMessages,
 100                                         'mr_lang' => $lang
 101                                 ), __METHOD__
 102                         );
 103                         foreach ( $res as $row ) {
 104                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
 105                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 106                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 107                         }
 108                 }
 109                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 110                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 111                 }
 112         }
 113
 114         /**
 115          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 116          *
 117          * Available filters are:
 118          *  - minify-js \see JavaScriptMinifier::minify
 119          *  - minify-css \see CSSMin::minify
 120          *
 121          * If $data is empty, only contains whitespace or the filter was unknown,
 122          * $data is returned unmodified.
 123          *
 124          * @param $filter String: Name of filter to run
 125          * @param $data String: Text to filter, such as JavaScript or CSS text
 126          * @return String: Filtered data, or a comment containing an error message
 127          */
 128         protected function filter( $filter, $data ) {
 129                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 130                 wfProfileIn( __METHOD__ );
 131
 132                 // For empty/whitespace-only data or for unknown filters, don't perform
 133                 // any caching or processing
 134                 if ( trim( $data ) === ''
 135                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 136                 {
 137                         wfProfileOut( __METHOD__ );
 138                         return $data;
 139                 }
 140
 141                 // Try for cache hit
 142                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 143                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 144                 $cache = wfGetCache( CACHE_ANYTHING );
 145                 $cacheEntry = $cache->get( $key );
 146                 if ( is_string( $cacheEntry ) ) {
 147                         wfProfileOut( __METHOD__ );
 148                         return $cacheEntry;
 149                 }
 150
 151                 $result = '';
 152                 // Run the filter - we've already verified one of these will work
 153                 try {
 154                         switch ( $filter ) {
 155                                 case 'minify-js':
 156                                         $result = JavaScriptMinifier::minify( $data,
 157                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 158                                                 $wgResourceLoaderMinifierMaxLineLength
 159                                         );
 160                                         $result .= "\n\n/* cache key: $key */\n";
 161                                         break;
 162                                 case 'minify-css':
 163                                         $result = CSSMin::minify( $data );
 164                                         $result .= "\n\n/* cache key: $key */\n";
 165                                         break;
 166                         }
 167
 168                         // Save filtered text to Memcached
 169                         $cache->set( $key, $result );
 170                 } catch ( Exception $exception ) {
 171                         // Return exception as a comment
 172                         $result = "/*\n{$exception->__toString()}\n*/\n";
 173                 }
 174
 175                 wfProfileOut( __METHOD__ );
 176
 177                 return $result;
 178         }
 179
 180         /* Methods */
 181
 182         /**
 183          * Registers core modules and runs registration hooks.
 184          */
 185         public function __construct() {
 186                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript;
 187
 188                 wfProfileIn( __METHOD__ );
 189
 190                 // Add 'local' source first
 191                 $this->addSource( 'local', array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) ) );
 192
 193                 // Add other sources
 194                 $this->addSource( $wgResourceLoaderSources );
 195
 196                 // Register core modules
 197                 $this->register( include( "$IP/resources/Resources.php" ) );
 198                 // Register extension modules
 199                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 200                 $this->register( $wgResourceModules );
 201
 202                 wfProfileOut( __METHOD__ );
 203         }
 204
 205         /**
 206          * Registers a module with the ResourceLoader system.
 207          *
 208          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 209          * @param $info Module info array. For backwards compatibility with 1.17alpha,
 210          *   this may also be a ResourceLoaderModule object. Optional when using
 211          *   multiple-registration calling style.
 212          * @throws MWException: If a duplicate module registration is attempted
 213          * @throws MWException: If a module name contains illegal characters (pipes or commas)
 214          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 215          * @return Boolean: False if there were any errors, in which case one or more modules were not
 216          *     registered
 217          */
 218         public function register( $name, $info = null ) {
 219                 wfProfileIn( __METHOD__ );
 220
 221                 // Allow multiple modules to be registered in one call
 222                 if ( is_array( $name ) ) {
 223                         foreach ( $name as $key => $value ) {
 224                                 $this->register( $key, $value );
 225                         }
 226                         wfProfileOut( __METHOD__ );
 227                         return;
 228                 }
 229
 230                 // Disallow duplicate registrations
 231                 if ( isset( $this->moduleInfos[$name] ) ) {
 232                         // A module has already been registered by this name
 233                         throw new MWException(
 234                                 'ResourceLoader duplicate registration error. ' .
 235                                 'Another module has already been registered as ' . $name
 236                         );
 237                 }
 238
 239                 // Check $name for illegal characters
 240                 if ( preg_match( '/[|,!]/', $name ) ) {
 241                         throw new MWException( "ResourceLoader module name '$name' is invalid. Names may not contain pipes (|), commas (,) or exclamation marks (!)" );
 242                 }
 243
 244                 // Attach module
 245                 if ( is_object( $info ) ) {
 246                         // Old calling convention
 247                         // Validate the input
 248                         if ( !( $info instanceof ResourceLoaderModule ) ) {
 249                                 throw new MWException( 'ResourceLoader invalid module error. ' .
 250                                         'Instances of ResourceLoaderModule expected.' );
 251                         }
 252
 253                         $this->moduleInfos[$name] = array( 'object' => $info );
 254                         $info->setName( $name );
 255                         $this->modules[$name] = $info;
 256                 } else {
 257                         // New calling convention
 258                         $this->moduleInfos[$name] = $info;
 259                 }
 260
 261                 wfProfileOut( __METHOD__ );
 262         }
 263
 264         /**
 265          * Add a foreign source of modules.
 266          *
 267          * Source properties:
 268          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 269          *
 270          * @param $id Mixed: source ID (string), or array( id1 => props1, id2 => props2, ... )
 271          * @param $properties Array: source properties
 272          */
 273         public function addSource( $id, $properties = null) {
 274                 // Allow multiple sources to be registered in one call
 275                 if ( is_array( $id ) ) {
 276                         foreach ( $id as $key => $value ) {
 277                                 $this->addSource( $key, $value );
 278                         }
 279                         return;
 280                 }
 281
 282                 // Disallow duplicates
 283                 if ( isset( $this->sources[$id] ) ) {
 284                         throw new MWException(
 285                                 'ResourceLoader duplicate source addition error. ' .
 286                                 'Another source has already been registered as ' . $id
 287                         );
 288                 }
 289
 290                 // Validate properties
 291                 foreach ( self::$requiredSourceProperties as $prop ) {
 292                         if ( !isset( $properties[$prop] ) ) {
 293                                 throw new MWException( "Required property $prop missing from source ID $id" );
 294                         }
 295                 }
 296
 297                 $this->sources[$id] = $properties;
 298         }
 299
 300         /**
 301          * Get a list of module names
 302          *
 303          * @return Array: List of module names
 304          */
 305         public function getModuleNames() {
 306                 return array_keys( $this->moduleInfos );
 307         }
 308
 309         /**
 310          * Get the ResourceLoaderModule object for a given module name.
 311          *
 312          * @param $name String: Module name
 313          * @return ResourceLoaderModule if module has been registered, null otherwise
 314          */
 315         public function getModule( $name ) {
 316                 if ( !isset( $this->modules[$name] ) ) {
 317                         if ( !isset( $this->moduleInfos[$name] ) ) {
 318                                 // No such module
 319                                 return null;
 320                         }
 321                         // Construct the requested object
 322                         $info = $this->moduleInfos[$name];
 323                         if ( isset( $info['object'] ) ) {
 324                                 // Object given in info array
 325                                 $object = $info['object'];
 326                         } else {
 327                                 if ( !isset( $info['class'] ) ) {
 328                                         $class = 'ResourceLoaderFileModule';
 329                                 } else {
 330                                         $class = $info['class'];
 331                                 }
 332                                 $object = new $class( $info );
 333                         }
 334                         $object->setName( $name );
 335                         $this->modules[$name] = $object;
 336                 }
 337
 338                 return $this->modules[$name];
 339         }
 340
 341         /**
 342          * Get the list of sources
 343          *
 344          * @return Array: array( id => array of properties, .. )
 345          */
 346         public function getSources() {
 347                 return $this->sources;
 348         }
 349
 350         /**
 351          * Outputs a response to a resource load-request, including a content-type header.
 352          *
 353          * @param $context ResourceLoaderContext: Context in which a response should be formed
 354          */
 355         public function respond( ResourceLoaderContext $context ) {
 356                 global $wgCacheEpoch, $wgUseFileCache;
 357
 358                 // Use file cache if enabled and available...
 359                 if ( $wgUseFileCache ) {
 360                         $fileCache = ResourceFileCache::newFromContext( $context );
 361                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 362                                 return; // output handled
 363                         }
 364                 }
 365
 366                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 367                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 368                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 369                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 370                 // the whole thing in our own output buffer to be sure the active buffer
 371                 // doesn't use ob_gzhandler.
 372                 // See http://bugs.php.net/bug.php?id=36514
 373                 ob_start();
 374
 375                 wfProfileIn( __METHOD__ );
 376                 $exceptions = '';
 377
 378                 // Split requested modules into two groups, modules and missing
 379                 $modules = array();
 380                 $missing = array();
 381                 foreach ( $context->getModules() as $name ) {
 382                         if ( isset( $this->moduleInfos[$name] ) ) {
 383                                 $modules[$name] = $this->getModule( $name );
 384                         } else {
 385                                 $missing[] = $name;
 386                         }
 387                 }
 388
 389                 // Preload information needed to the mtime calculation below
 390                 try {
 391                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 392                 } catch( Exception $e ) {
 393                         // Add exception to the output as a comment
 394                         $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 395                 }
 396
 397                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 398
 399                 $private = false;
 400                 // To send Last-Modified and support If-Modified-Since, we need to detect
 401                 // the last modified time
 402                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 403                 foreach ( $modules as $module ) {
 404                         /**
 405                          * @var $module ResourceLoaderModule
 406                          */
 407                         try {
 408                                 // Bypass Squid and other shared caches if the request includes any private modules
 409                                 if ( $module->getGroup() === 'private' ) {
 410                                         $private = true;
 411                                 }
 412                                 // Calculate maximum modified time
 413                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 414                         } catch ( Exception $e ) {
 415                                 // Add exception to the output as a comment
 416                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 417                         }
 418                 }
 419
 420                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 421
 422                 // Send content type and cache related headers
 423                 $this->sendResponseHeaders( $context, $mtime, $private );
 424
 425                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 426                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 427                         wfProfileOut( __METHOD__ );
 428                         return; // output handled (buffers cleared)
 429                 }
 430
 431                 // Generate a response
 432                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 433
 434                 // Prepend comments indicating exceptions
 435                 $response = $exceptions . $response;
 436
 437                 // Capture any PHP warnings from the output buffer and append them to the
 438                 // response in a comment if we're in debug mode.
 439                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 440                         $response = "/*\n$warnings\n*/\n" . $response;
 441                 }
 442
 443                 // Remove the output buffer and output the response
 444                 ob_end_clean();
 445                 echo $response;
 446
 447                 // Save response to file cache unless there are private modules or errors
 448                 if ( isset( $fileCache ) && !$private && !$exceptions && !$missing ) {
 449                         // Cache single modules...and other requests if there are enough hits
 450                         if ( ResourceFileCache::useFileCache( $context ) ) {
 451                                 if ( $fileCache->isCacheWorthy() ) {
 452                                         $fileCache->saveText( $response );
 453                                 } else {
 454                                         $fileCache->incrMissesRecent( $context->getRequest() );
 455                                 }
 456                         }
 457                 }
 458
 459                 wfProfileOut( __METHOD__ );
 460         }
 461
 462         /**
 463          * Send content type and last modified headers to the client.
 464          * @param $context ResourceLoaderContext
 465          * @param $mtime string TS_MW timestamp to use for last-modified
 466          * @param $private bool True iff response contains any private modules
 467          * @return void
 468          */
 469         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $private ) {
 470                 global $wgResourceLoaderMaxage;
 471                 // If a version wasn't specified we need a shorter expiry time for updates
 472                 // to propagate to clients quickly
 473                 if ( is_null( $context->getVersion() ) ) {
 474                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 475                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 476                 // If a version was specified we can use a longer expiry time since changing
 477                 // version numbers causes cache misses
 478                 } else {
 479                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 480                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 481                 }
 482                 if ( $context->getOnly() === 'styles' ) {
 483                         header( 'Content-Type: text/css; charset=utf-8' );
 484                 } else {
 485                         header( 'Content-Type: text/javascript; charset=utf-8' );
 486                 }
 487                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 488                 if ( $context->getDebug() ) {
 489                         // Do not cache debug responses
 490                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 491                         header( 'Pragma: no-cache' );
 492                 } else {
 493                         if ( $private ) {
 494                                 header( "Cache-Control: private, max-age=$maxage" );
 495                                 $exp = $maxage;
 496                         } else {
 497                                 header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 498                                 $exp = min( $maxage, $smaxage );
 499                         }
 500                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 501                 }
 502         }
 503
 504         /**
 505          * If there's an If-Modified-Since header, respond with a 304 appropriately
 506          * and clear out the output buffer. If the client cache is too old then do nothing.
 507          * @param $context ResourceLoaderContext
 508          * @param $mtime string The TS_MW timestamp to check the header against
 509          * @return bool True iff 304 header sent and output handled
 510          */
 511         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 512                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 513                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 514                 // so we get a valid timestamp.
 515                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 516                 // Never send 304s in debug mode
 517                 if ( $ims !== false && !$context->getDebug() ) {
 518                         $imsTS = strtok( $ims, ';' );
 519                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 520                                 // There's another bug in ob_gzhandler (see also the comment at
 521                                 // the top of this function) that causes it to gzip even empty
 522                                 // responses, meaning it's impossible to produce a truly empty
 523                                 // response (because the gzip header is always there). This is
 524                                 // a problem because 304 responses have to be completely empty
 525                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 526                                 // See also http://bugs.php.net/bug.php?id=51579
 527                                 // To work around this, we tear down all output buffering before
 528                                 // sending the 304.
 529                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 530                                 // no matter how often we call ob_get_clean(), so instead of doing
 531                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 532                                 // we have to be safe here and avoid an infinite loop.
 533                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 534                                         ob_end_clean();
 535                                 }
 536
 537                                 header( 'HTTP/1.0 304 Not Modified' );
 538                                 header( 'Status: 304 Not Modified' );
 539                                 wfProfileOut( __METHOD__ );
 540                                 return true;
 541                         }
 542                 }
 543                 return false;
 544         }
 545
 546         /**
 547          * Send out code for a response from file cache if possible
 548          *
 549          * @param $fileCache ObjectFileCache: Cache object for this request URL
 550          * @param $context ResourceLoaderContext: Context in which to generate a response
 551          * @return bool If this found a cache file and handled the response
 552          */
 553         protected function tryRespondFromFileCache(
 554                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 555         ) {
 556                 global $wgResourceLoaderMaxage;
 557                 // Buffer output to catch warnings.
 558                 ob_start();
 559                 // Get the maximum age the cache can be
 560                 $maxage = is_null( $context->getVersion() )
 561                         ? $wgResourceLoaderMaxage['unversioned']['server']
 562                         : $wgResourceLoaderMaxage['versioned']['server'];
 563                 // Minimum timestamp the cache file must have
 564                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 565                 if ( !$good ) {
 566                         try { // RL always hits the DB on file cache miss...
 567                                 wfGetDB( DB_SLAVE );
 568                         } catch( DBConnectionError $e ) { // ...check if we need to fallback to cache
 569                                 $good = $fileCache->isCacheGood(); // cache existence check
 570                         }
 571                 }
 572                 if ( $good ) {
 573                         $ts = $fileCache->cacheTimestamp();
 574                         // Send content type and cache headers
 575                         $this->sendResponseHeaders( $context, $ts, false );
 576                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 577                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 578                                 return false; // output handled (buffers cleared)
 579                         }
 580                         $response = $fileCache->fetchText();
 581                         // Remove the output buffer and output the response
 582                         ob_end_clean();
 583                         echo $response . "\n/* Cached {$ts} */";
 584                         return true; // cache hit
 585                 }
 586                 // Clear buffer
 587                 ob_end_clean();
 588
 589                 return false; // cache miss
 590         }
 591
 592         /**
 593          * Generates code for a response
 594          *
 595          * @param $context ResourceLoaderContext: Context in which to generate a response
 596          * @param $modules Array: List of module objects keyed by module name
 597          * @param $missing Array: List of unavailable modules (optional)
 598          * @return String: Response data
 599          */
 600         public function makeModuleResponse( ResourceLoaderContext $context,
 601                 array $modules, $missing = array() )
 602         {
 603                 $out = '';
 604                 $exceptions = '';
 605                 if ( $modules === array() && $missing === array() ) {
 606                         return '/* No modules requested. Max made me put this here */';
 607                 }
 608
 609                 wfProfileIn( __METHOD__ );
 610                 // Pre-fetch blobs
 611                 if ( $context->shouldIncludeMessages() ) {
 612                         try {
 613                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 614                         } catch ( Exception $e ) {
 615                                 // Add exception to the output as a comment
 616                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 617                         }
 618                 } else {
 619                         $blobs = array();
 620                 }
 621
 622                 // Generate output
 623                 foreach ( $modules as $name => $module ) {
 624                         /**
 625                          * @var $module ResourceLoaderModule
 626                          */
 627
 628                         wfProfileIn( __METHOD__ . '-' . $name );
 629                         try {
 630                                 $scripts = '';
 631                                 if ( $context->shouldIncludeScripts() ) {
 632                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 633                                         // However, we can't do this if the module doesn't support it
 634                                         // We also can't do this if there is an only= parameter, because we have to give
 635                                         // the module a way to return a load.php URL without causing an infinite loop
 636                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 637                                                 $scripts = $module->getScriptURLsForDebug( $context );
 638                                         } else {
 639                                                 $scripts = $module->getScript( $context );
 640                                                 if ( is_string( $scripts ) ) {
 641                                                         // bug 27054: Append semicolon to prevent weird bugs
 642                                                         // caused by files not terminating their statements right
 643                                                         $scripts .= ";\n";
 644                                                 }
 645                                         }
 646                                 }
 647                                 // Styles
 648                                 $styles = array();
 649                                 if ( $context->shouldIncludeStyles() ) {
 650                                         // If we are in debug mode, we'll want to return an array of URLs
 651                                         // See comment near shouldIncludeScripts() for more details
 652                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 653                                                 $styles = $module->getStyleURLsForDebug( $context );
 654                                         } else {
 655                                                 $styles = $module->getStyles( $context );
 656                                         }
 657                                 }
 658
 659                                 // Messages
 660                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 661
 662                                 // Append output
 663                                 switch ( $context->getOnly() ) {
 664                                         case 'scripts':
 665                                                 if ( is_string( $scripts ) ) {
 666                                                         // Load scripts raw...
 667                                                         $out .= $scripts;
 668                                                 } elseif ( is_array( $scripts ) ) {
 669                                                         // ...except when $scripts is an array of URLs
 670                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 671                                                 }
 672                                                 break;
 673                                         case 'styles':
 674                                                 $out .= self::makeCombinedStyles( $styles );
 675                                                 break;
 676                                         case 'messages':
 677                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 678                                                 break;
 679                                         default:
 680                                                 // Minify CSS before embedding in mw.loader.implement call
 681                                                 // (unless in debug mode)
 682                                                 if ( !$context->getDebug() ) {
 683                                                         foreach ( $styles as $media => $style ) {
 684                                                                 if ( is_string( $style ) ) {
 685                                                                         $styles[$media] = $this->filter( 'minify-css', $style );
 686                                                                 }
 687                                                         }
 688                                                 }
 689                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 690                                                         new XmlJsCode( $messagesBlob ) );
 691                                                 break;
 692                                 }
 693                         } catch ( Exception $e ) {
 694                                 // Add exception to the output as a comment
 695                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 696
 697                                 // Register module as missing
 698                                 $missing[] = $name;
 699                                 unset( $modules[$name] );
 700                         }
 701                         wfProfileOut( __METHOD__ . '-' . $name );
 702                 }
 703
 704                 // Update module states
 705                 if ( $context->shouldIncludeScripts() ) {
 706                         // Set the state of modules loaded as only scripts to ready
 707                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 708                                 && !isset( $modules['startup'] ) )
 709                         {
 710                                 $out .= self::makeLoaderStateScript(
 711                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 712                         }
 713                         // Set the state of modules which were requested but unavailable as missing
 714                         if ( is_array( $missing ) && count( $missing ) ) {
 715                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 716                         }
 717                 }
 718
 719                 if ( !$context->getDebug() ) {
 720                         if ( $context->getOnly() === 'styles' ) {
 721                                 $out = $this->filter( 'minify-css', $out );
 722                         } else {
 723                                 $out = $this->filter( 'minify-js', $out );
 724                         }
 725                 }
 726
 727                 wfProfileOut( __METHOD__ );
 728                 return $exceptions . $out;
 729         }
 730
 731         /* Static Methods */
 732
 733         /**
 734          * Returns JS code to call to mw.loader.implement for a module with
 735          * given properties.
 736          *
 737          * @param $name Module name
 738          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 739          * @param $styles Mixed: List of CSS strings keyed by media type, or list of lists of URLs to
 740          * CSS files keyed by media type
 741          * @param $messages Mixed: List of messages associated with this module. May either be an
 742          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 743          *     the same data, wrapped in an XmlJsCode object.
 744          *
 745          * @return string
 746          */
 747         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 748                 if ( is_string( $scripts ) ) {
 749                         $scripts = new XmlJsCode( "function( $ ) {{$scripts}}" );
 750                 } elseif ( !is_array( $scripts ) ) {
 751                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 752                 }
 753                 return Xml::encodeJsCall(
 754                         'mw.loader.implement',
 755                         array(
 756                                 $name,
 757                                 $scripts,
 758                                 (object)$styles,
 759                                 (object)$messages
 760                         ) );
 761         }
 762
 763         /**
 764          * Returns JS code which, when called, will register a given list of messages.
 765          *
 766          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 767          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 768          *
 769          * @return string
 770          */
 771         public static function makeMessageSetScript( $messages ) {
 772                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 773         }
 774
 775         /**
 776          * Combines an associative array mapping media type to CSS into a
 777          * single stylesheet with @media blocks.
 778          *
 779          * @param $styles Array: List of CSS strings keyed by media type
 780          *
 781          * @return string
 782          */
 783         public static function makeCombinedStyles( array $styles ) {
 784                 $out = '';
 785                 foreach ( $styles as $media => $style ) {
 786                         // Transform the media type based on request params and config
 787                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 788                         $media = OutputPage::transformCssMedia( $media );
 789
 790                         if ( $media === null ) {
 791                                 // Skip
 792                         } elseif ( $media === '' || $media == 'all' ) {
 793                                 // Don't output invalid or frivolous @media statements
 794                                 $out .= "$style\n";
 795                         } else {
 796                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 797                         }
 798                 }
 799                 return $out;
 800         }
 801
 802         /**
 803          * Returns a JS call to mw.loader.state, which sets the state of a
 804          * module or modules to a given value. Has two calling conventions:
 805          *
 806          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 807          *         Set the state of a single module called $name to $state
 808          *
 809          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 810          *         Set the state of modules with the given names to the given states
 811          *
 812          * @param $name string
 813          * @param $state
 814          *
 815          * @return string
 816          */
 817         public static function makeLoaderStateScript( $name, $state = null ) {
 818                 if ( is_array( $name ) ) {
 819                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 820                 } else {
 821                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 822                 }
 823         }
 824
 825         /**
 826          * Returns JS code which calls the script given by $script. The script will
 827          * be called with local variables name, version, dependencies and group,
 828          * which will have values corresponding to $name, $version, $dependencies
 829          * and $group as supplied.
 830          *
 831          * @param $name String: Module name
 832          * @param $version Integer: Module version number as a timestamp
 833          * @param $dependencies Array: List of module names on which this module depends
 834          * @param $group String: Group which the module is in.
 835          * @param $source String: Source of the module, or 'local' if not foreign.
 836          * @param $script String: JavaScript code
 837          *
 838          * @return string
 839          */
 840         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 841                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 842                 return Xml::encodeJsCall(
 843                         "( function( name, version, dependencies, group, source ) {\n\t$script\n} )",
 844                         array( $name, $version, $dependencies, $group, $source ) );
 845         }
 846
 847         /**
 848          * Returns JS code which calls mw.loader.register with the given
 849          * parameters. Has three calling conventions:
 850          *
 851          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 852          *       Register a single module.
 853          *
 854          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 855          *       Register modules with the given names.
 856          *
 857          *   - ResourceLoader::makeLoaderRegisterScript( array(
 858          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 859          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 860          *        ...
 861          *     ) ):
 862          *        Registers modules with the given names and parameters.
 863          *
 864          * @param $name String: Module name
 865          * @param $version Integer: Module version number as a timestamp
 866          * @param $dependencies Array: List of module names on which this module depends
 867          * @param $group String: group which the module is in.
 868          * @param $source String: source of the module, or 'local' if not foreign
 869          *
 870          * @return string
 871          */
 872         public static function makeLoaderRegisterScript( $name, $version = null,
 873                 $dependencies = null, $group = null, $source = null )
 874         {
 875                 if ( is_array( $name ) ) {
 876                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 877                 } else {
 878                         $version = (int) $version > 1 ? (int) $version : 1;
 879                         return Xml::encodeJsCall( 'mw.loader.register',
 880                                 array( $name, $version, $dependencies, $group, $source ) );
 881                 }
 882         }
 883
 884         /**
 885          * Returns JS code which calls mw.loader.addSource() with the given
 886          * parameters. Has two calling conventions:
 887          *
 888          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
 889          *       Register a single source
 890          *
 891          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
 892          *       Register sources with the given IDs and properties.
 893          *
 894          * @param $id String: source ID
 895          * @param $properties Array: source properties (see addSource())
 896          *
 897          * @return string
 898          */
 899         public static function makeLoaderSourcesScript( $id, $properties = null ) {
 900                 if ( is_array( $id ) ) {
 901                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
 902                 } else {
 903                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
 904                 }
 905         }
 906
 907         /**
 908          * Returns JS code which runs given JS code if the client-side framework is
 909          * present.
 910          *
 911          * @param $script String: JavaScript code
 912          *
 913          * @return string
 914          */
 915         public static function makeLoaderConditionalScript( $script ) {
 916                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 917                 return "if(window.mw){\n\t$script\n}\n";
 918         }
 919
 920         /**
 921          * Returns JS code which will set the MediaWiki configuration array to
 922          * the given value.
 923          *
 924          * @param $configuration Array: List of configuration values keyed by variable name
 925          *
 926          * @return string
 927          */
 928         public static function makeConfigSetScript( array $configuration ) {
 929                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
 930         }
 931
 932         /**
 933          * Convert an array of module names to a packed query string.
 934          *
 935          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
 936          * becomes 'foo.bar,baz|bar.baz,quux'
 937          * @param $modules array of module names (strings)
 938          * @return string Packed query string
 939          */
 940         public static function makePackedModulesString( $modules ) {
 941                 $groups = array(); // array( prefix => array( suffixes ) )
 942                 foreach ( $modules as $module ) {
 943                         $pos = strrpos( $module, '.' );
 944                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
 945                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
 946                         $groups[$prefix][] = $suffix;
 947                 }
 948
 949                 $arr = array();
 950                 foreach ( $groups as $prefix => $suffixes ) {
 951                         $p = $prefix === '' ? '' : $prefix . '.';
 952                         $arr[] = $p . implode( ',', $suffixes );
 953                 }
 954                 $str = implode( '|', $arr );
 955                 return $str;
 956         }
 957
 958         /**
 959          * Determine whether debug mode was requested
 960          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
 961          * @return bool
 962          */
 963         public static function inDebugMode() {
 964                 global $wgRequest, $wgResourceLoaderDebug;
 965                 static $retval = null;
 966                 if ( !is_null( $retval ) ) {
 967                         return $retval;
 968                 }
 969                 return $retval = $wgRequest->getFuzzyBool( 'debug',
 970                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
 971         }
 972
 973         /**
 974          * Build a load.php URL
 975          * @param $modules array of module names (strings)
 976          * @param $lang string Language code
 977          * @param $skin string Skin name
 978          * @param $user string|null User name. If null, the &user= parameter is omitted
 979          * @param $version string|null Versioning timestamp
 980          * @param $debug bool Whether the request should be in debug mode
 981          * @param $only string|null &only= parameter
 982          * @param $printable bool Printable mode
 983          * @param $handheld bool Handheld mode
 984          * @param $extraQuery array Extra query parameters to add
 985          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
 986          */
 987         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
 988                         $printable = false, $handheld = false, $extraQuery = array() ) {
 989                 global $wgLoadScript;
 990                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
 991                         $only, $printable, $handheld, $extraQuery
 992                 );
 993
 994                 // Prevent the IE6 extension check from being triggered (bug 28840)
 995                 // by appending a character that's invalid in Windows extensions ('*')
 996                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
 997         }
 998
 999         /**
1000          * Build a query array (array representation of query string) for load.php. Helper
1001          * function for makeLoaderURL().
1002          * @return array
1003          */
1004         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1005                         $printable = false, $handheld = false, $extraQuery = array() ) {
1006                 $query = array(
1007                         'modules' => self::makePackedModulesString( $modules ),
1008                         'lang' => $lang,
1009                         'skin' => $skin,
1010                         'debug' => $debug ? 'true' : 'false',
1011                 );
1012                 if ( $user !== null ) {
1013                         $query['user'] = $user;
1014                 }
1015                 if ( $version !== null ) {
1016                         $query['version'] = $version;
1017                 }
1018                 if ( $only !== null ) {
1019                         $query['only'] = $only;
1020                 }
1021                 if ( $printable ) {
1022                         $query['printable'] = 1;
1023                 }
1024                 if ( $handheld ) {
1025                         $query['handheld'] = 1;
1026                 }
1027                 $query += $extraQuery;
1028
1029                 // Make queries uniform in order
1030                 ksort( $query );
1031                 return $query;
1032         }
1033 }