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
  33         /** Array: List of module name/ResourceLoaderModule object pairs */
  34         protected $modules = array();
  35         /** Associative array mapping module name to info associative array */
  36         protected $moduleInfos = array();
  37
  38         /* Protected Methods */
  39
  40         /**
  41          * Loads information stored in the database about modules.
  42          *
  43          * This method grabs modules dependencies from the database and updates modules
  44          * objects.
  45          *
  46          * This is not inside the module code because it is much faster to
  47          * request all of the information at once than it is to have each module
  48          * requests its own information. This sacrifice of modularity yields a substantial
  49          * performance improvement.
  50          *
  51          * @param $modules Array: List of module names to preload information for
  52          * @param $context ResourceLoaderContext: Context to load the information within
  53          */
  54         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  55                 if ( !count( $modules ) ) {
  56                         return; // or else Database*::select() will explode, plus it's cheaper!
  57                 }
  58                 $dbr = wfGetDB( DB_SLAVE );
  59                 $skin = $context->getSkin();
  60                 $lang = $context->getLanguage();
  61
  62                 // Get file dependency information
  63                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  64                                 'md_module' => $modules,
  65                                 'md_skin' => $context->getSkin()
  66                         ), __METHOD__
  67                 );
  68
  69                 // Set modules' dependencies
  70                 $modulesWithDeps = array();
  71                 foreach ( $res as $row ) {
  72                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  73                                 FormatJson::decode( $row->md_deps, true )
  74                         );
  75                         $modulesWithDeps[] = $row->md_module;
  76                 }
  77
  78                 // Register the absence of a dependency row too
  79                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  80                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  81                 }
  82
  83                 // Get message blob mtimes. Only do this for modules with messages
  84                 $modulesWithMessages = array();
  85                 foreach ( $modules as $name ) {
  86                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  87                                 $modulesWithMessages[] = $name;
  88                         }
  89                 }
  90                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
  91                 if ( count( $modulesWithMessages ) ) {
  92                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
  93                                         'mr_resource' => $modulesWithMessages,
  94                                         'mr_lang' => $lang
  95                                 ), __METHOD__
  96                         );
  97                         foreach ( $res as $row ) {
  98                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
  99                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 100                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 101                         }
 102                 }
 103                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 104                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 105                 }
 106         }
 107
 108         /**
 109          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 110          *
 111          * Available filters are:
 112          *  - minify-js \see JavaScriptDistiller::stripWhiteSpace
 113          *  - minify-css \see CSSMin::minify
 114          *
 115          * If $data is empty, only contains whitespace or the filter was unknown,
 116          * $data is returned unmodified.
 117          *
 118          * @param $filter String: Name of filter to run
 119          * @param $data String: Text to filter, such as JavaScript or CSS text
 120          * @return String: Filtered data, or a comment containing an error message
 121          */
 122         protected function filter( $filter, $data ) {
 123                 global $wgResourceLoaderMinifyJSVerticalSpace;
 124
 125                 wfProfileIn( __METHOD__ );
 126
 127                 // For empty/whitespace-only data or for unknown filters, don't perform
 128                 // any caching or processing
 129                 if ( trim( $data ) === ''
 130                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 131                 {
 132                         wfProfileOut( __METHOD__ );
 133                         return $data;
 134                 }
 135
 136                 // Try for cache hit
 137                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 138                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, md5( $data ) );
 139                 $cache = wfGetCache( CACHE_ANYTHING );
 140                 $cacheEntry = $cache->get( $key );
 141                 if ( is_string( $cacheEntry ) ) {
 142                         wfProfileOut( __METHOD__ );
 143                         return $cacheEntry;
 144                 }
 145
 146                 $result = '';
 147                 // Run the filter - we've already verified one of these will work
 148                 try {
 149                         switch ( $filter ) {
 150                                 case 'minify-js':
 151                                         $result = JavaScriptDistiller::stripWhiteSpace(
 152                                                 $data, $wgResourceLoaderMinifyJSVerticalSpace
 153                                         );
 154                                         break;
 155                                 case 'minify-css':
 156                                         $result = CSSMin::minify( $data );
 157                                         break;
 158                         }
 159
 160                         // Save filtered text to Memcached
 161                         $cache->set( $key, $result );
 162                 } catch ( Exception $exception ) {
 163                         // Return exception as a comment
 164                         $result = "/*\n{$exception->__toString()}\n*/\n";
 165                 }
 166
 167                 wfProfileOut( __METHOD__ );
 168
 169                 return $result;
 170         }
 171
 172         /* Methods */
 173
 174         /**
 175          * Registers core modules and runs registration hooks.
 176          */
 177         public function __construct() {
 178                 global $IP, $wgResourceModules;
 179
 180                 wfProfileIn( __METHOD__ );
 181
 182                 // Register core modules
 183                 $this->register( include( "$IP/resources/Resources.php" ) );
 184                 // Register extension modules
 185                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 186                 $this->register( $wgResourceModules );
 187
 188                 wfProfileOut( __METHOD__ );
 189         }
 190
 191         /**
 192          * Registers a module with the ResourceLoader system.
 193          *
 194          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 195          * @param $info Module info array. For backwards compatibility with 1.17alpha,
 196          *   this may also be a ResourceLoaderModule object. Optional when using
 197          *   multiple-registration calling style.
 198          * @throws MWException: If a duplicate module registration is attempted
 199          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 200          * @return Boolean: False if there were any errors, in which case one or more modules were not
 201          *     registered
 202          */
 203         public function register( $name, $info = null ) {
 204                 wfProfileIn( __METHOD__ );
 205
 206                 // Allow multiple modules to be registered in one call
 207                 if ( is_array( $name ) ) {
 208                         foreach ( $name as $key => $value ) {
 209                                 $this->register( $key, $value );
 210                         }
 211                         wfProfileOut( __METHOD__ );
 212                         return;
 213                 }
 214
 215                 // Disallow duplicate registrations
 216                 if ( isset( $this->moduleInfos[$name] ) ) {
 217                         // A module has already been registered by this name
 218                         throw new MWException(
 219                                 'ResourceLoader duplicate registration error. ' .
 220                                 'Another module has already been registered as ' . $name
 221                         );
 222                 }
 223
 224                 // Attach module
 225                 if ( is_object( $info ) ) {
 226                         // Old calling convention
 227                         // Validate the input
 228                         if ( !( $info instanceof ResourceLoaderModule ) ) {
 229                                 throw new MWException( 'ResourceLoader invalid module error. ' .
 230                                         'Instances of ResourceLoaderModule expected.' );
 231                         }
 232
 233                         $this->moduleInfos[$name] = array( 'object' => $info );
 234                         $info->setName( $name );
 235                         $this->modules[$name] = $info;
 236                 } else {
 237                         // New calling convention
 238                         $this->moduleInfos[$name] = $info;
 239                 }
 240
 241                 wfProfileOut( __METHOD__ );
 242         }
 243
 244         /**
 245          * Get a list of module names
 246          *
 247          * @return Array: List of module names
 248          */
 249         public function getModuleNames() {
 250                 return array_keys( $this->moduleInfos );
 251         }
 252
 253         /**
 254          * Get the ResourceLoaderModule object for a given module name.
 255          *
 256          * @param $name String: Module name
 257          * @return ResourceLoaderModule if module has been registered, null otherwise
 258          */
 259         public function getModule( $name ) {
 260                 if ( !isset( $this->modules[$name] ) ) {
 261                         if ( !isset( $this->moduleInfos[$name] ) ) {
 262                                 // No such module
 263                                 return null;
 264                         }
 265                         // Construct the requested object
 266                         $info = $this->moduleInfos[$name];
 267                         if ( isset( $info['object'] ) ) {
 268                                 // Object given in info array
 269                                 $object = $info['object'];
 270                         } else {
 271                                 if ( !isset( $info['class'] ) ) {
 272                                         $class = 'ResourceLoaderFileModule';
 273                                 } else {
 274                                         $class = $info['class'];
 275                                 }
 276                                 $object = new $class( $info );
 277                         }
 278                         $object->setName( $name );
 279                         $this->modules[$name] = $object;
 280                 }
 281
 282                 return $this->modules[$name];
 283         }
 284
 285         /**
 286          * Outputs a response to a resource load-request, including a content-type header.
 287          *
 288          * @param $context ResourceLoaderContext: Context in which a response should be formed
 289          */
 290         public function respond( ResourceLoaderContext $context ) {
 291                 global $wgResourceLoaderMaxage, $wgCacheEpoch;
 292
 293                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 294                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 295                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 296                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 297                 // the whole thing in our own output buffer to be sure the active buffer
 298                 // doesn't use ob_gzhandler.
 299                 // See http://bugs.php.net/bug.php?id=36514
 300                 ob_start();
 301
 302                 wfProfileIn( __METHOD__ );
 303                 $exceptions = '';
 304
 305                 // Split requested modules into two groups, modules and missing
 306                 $modules = array();
 307                 $missing = array();
 308                 foreach ( $context->getModules() as $name ) {
 309                         if ( isset( $this->moduleInfos[$name] ) ) {
 310                                 $modules[$name] = $this->getModule( $name );
 311                         } else {
 312                                 $missing[] = $name;
 313                         }
 314                 }
 315
 316                 // If a version wasn't specified we need a shorter expiry time for updates
 317                 // to propagate to clients quickly
 318                 if ( is_null( $context->getVersion() ) ) {
 319                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 320                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 321                 }
 322                 // If a version was specified we can use a longer expiry time since changing
 323                 // version numbers causes cache misses
 324                 else {
 325                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 326                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 327                 }
 328
 329                 // Preload information needed to the mtime calculation below
 330                 try {
 331                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 332                 } catch( Exception $e ) {
 333                         // Add exception to the output as a comment
 334                         $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 335                 }
 336
 337                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 338
 339                 $private = false;
 340                 // To send Last-Modified and support If-Modified-Since, we need to detect
 341                 // the last modified time
 342                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 343                 foreach ( $modules as $module ) {
 344                         try {
 345                                 // Bypass Squid and other shared caches if the request includes any private modules
 346                                 if ( $module->getGroup() === 'private' ) {
 347                                         $private = true;
 348                                 }
 349                                 // Calculate maximum modified time
 350                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 351                         } catch ( Exception $e ) {
 352                                 // Add exception to the output as a comment
 353                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 354                         }
 355                 }
 356
 357                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 358
 359                 if ( $context->getOnly() === 'styles' ) {
 360                         header( 'Content-Type: text/css' );
 361                 } else {
 362                         header( 'Content-Type: text/javascript' );
 363                 }
 364                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 365                 if ( $context->getDebug() ) {
 366                         // Do not cache debug responses
 367                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 368                         header( 'Pragma: no-cache' );
 369                 } else {
 370                         if ( $private ) {
 371                                 header( "Cache-Control: private, max-age=$maxage" );
 372                                 $exp = $maxage;
 373                         } else {
 374                                 header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 375                                 $exp = min( $maxage, $smaxage );
 376                         }
 377                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 378                 }
 379
 380                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 381                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 382                 // so we get a valid timestamp.
 383                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 384                 // Never send 304s in debug mode
 385                 if ( $ims !== false && !$context->getDebug() ) {
 386                         $imsTS = strtok( $ims, ';' );
 387                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 388                                 // There's another bug in ob_gzhandler (see also the comment at
 389                                 // the top of this function) that causes it to gzip even empty
 390                                 // responses, meaning it's impossible to produce a truly empty
 391                                 // response (because the gzip header is always there). This is
 392                                 // a problem because 304 responses have to be completely empty
 393                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 394                                 // See also http://bugs.php.net/bug.php?id=51579
 395                                 // To work around this, we tear down all output buffering before
 396                                 // sending the 304.
 397                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 398                                 // no matter how often we call ob_get_clean(), so instead of doing
 399                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 400                                 // we have to be safe here and avoid an infinite loop.
 401                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 402                                         ob_end_clean();
 403                                 }
 404
 405                                 header( 'HTTP/1.0 304 Not Modified' );
 406                                 header( 'Status: 304 Not Modified' );
 407                                 wfProfileOut( __METHOD__ );
 408                                 return;
 409                         }
 410                 }
 411
 412                 // Generate a response
 413                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 414
 415                 // Prepend comments indicating exceptions
 416                 $response = $exceptions . $response;
 417
 418                 // Capture any PHP warnings from the output buffer and append them to the
 419                 // response in a comment if we're in debug mode.
 420                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 421                         $response = "/*\n$warnings\n*/\n" . $response;
 422                 }
 423
 424                 // Remove the output buffer and output the response
 425                 ob_end_clean();
 426                 echo $response;
 427
 428                 wfProfileOut( __METHOD__ );
 429         }
 430
 431         /**
 432          * Generates code for a response
 433          *
 434          * @param $context ResourceLoaderContext: Context in which to generate a response
 435          * @param $modules Array: List of module objects keyed by module name
 436          * @param $missing Array: List of unavailable modules (optional)
 437          * @return String: Response data
 438          */
 439         public function makeModuleResponse( ResourceLoaderContext $context,
 440                 array $modules, $missing = array() )
 441         {
 442                 $out = '';
 443                 $exceptions = '';
 444                 if ( $modules === array() && $missing === array() ) {
 445                         return '/* No modules requested. Max made me put this here */';
 446                 }
 447
 448                 wfProfileIn( __METHOD__ );
 449                 // Pre-fetch blobs
 450                 if ( $context->shouldIncludeMessages() ) {
 451                         try {
 452                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 453                         } catch ( Exception $e ) {
 454                                 // Add exception to the output as a comment
 455                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 456                         }
 457                 } else {
 458                         $blobs = array();
 459                 }
 460
 461                 // Generate output
 462                 foreach ( $modules as $name => $module ) {
 463                         wfProfileIn( __METHOD__ . '-' . $name );
 464                         try {
 465                                 // Scripts
 466                                 $scripts = '';
 467                                 if ( $context->shouldIncludeScripts() ) {
 468                                         $scripts .= $module->getScript( $context ) . "\n";
 469                                 }
 470
 471                                 // Styles
 472                                 $styles = array();
 473                                 if ( $context->shouldIncludeStyles() ) {
 474                                         $styles = $module->getStyles( $context );
 475                                 }
 476
 477                                 // Messages
 478                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 479
 480                                 // Append output
 481                                 switch ( $context->getOnly() ) {
 482                                         case 'scripts':
 483                                                 $out .= $scripts;
 484                                                 break;
 485                                         case 'styles':
 486                                                 $out .= self::makeCombinedStyles( $styles );
 487                                                 break;
 488                                         case 'messages':
 489                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 490                                                 break;
 491                                         default:
 492                                                 // Minify CSS before embedding in mediaWiki.loader.implement call
 493                                                 // (unless in debug mode)
 494                                                 if ( !$context->getDebug() ) {
 495                                                         foreach ( $styles as $media => $style ) {
 496                                                                 $styles[$media] = $this->filter( 'minify-css', $style );
 497                                                         }
 498                                                 }
 499                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 500                                                         new XmlJsCode( $messagesBlob ) );
 501                                                 break;
 502                                 }
 503                         } catch ( Exception $e ) {
 504                                 // Add exception to the output as a comment
 505                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 506
 507                                 // Register module as missing
 508                                 $missing[] = $name;
 509                                 unset( $modules[$name] );
 510                         }
 511                         wfProfileOut( __METHOD__ . '-' . $name );
 512                 }
 513
 514                 // Update module states
 515                 if ( $context->shouldIncludeScripts() ) {
 516                         // Set the state of modules loaded as only scripts to ready
 517                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 518                                 && !isset( $modules['startup'] ) )
 519                         {
 520                                 $out .= self::makeLoaderStateScript(
 521                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 522                         }
 523                         // Set the state of modules which were requested but unavailable as missing
 524                         if ( is_array( $missing ) && count( $missing ) ) {
 525                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 526                         }
 527                 }
 528
 529                 if ( !$context->getDebug() ) {
 530                         if ( $context->getOnly() === 'styles' ) {
 531                                 $out = $this->filter( 'minify-css', $out );
 532                         } else {
 533                                 $out = $this->filter( 'minify-js', $out );
 534                         }
 535                 }
 536
 537                 wfProfileOut( __METHOD__ );
 538                 return $exceptions . $out;
 539         }
 540
 541         /* Static Methods */
 542
 543         /**
 544          * Returns JS code to call to mediaWiki.loader.implement for a module with
 545          * given properties.
 546          *
 547          * @param $name Module name
 548          * @param $scripts Array: List of JavaScript code snippets to be executed after the
 549          *     module is loaded
 550          * @param $styles Array: List of CSS strings keyed by media type
 551          * @param $messages Mixed: List of messages associated with this module. May either be an
 552          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 553          *     the same data, wrapped in an XmlJsCode object.
 554          */
 555         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 556                 if ( is_array( $scripts ) ) {
 557                         $scripts = implode( $scripts, "\n" );
 558                 }
 559                 return Xml::encodeJsCall(
 560                         'mediaWiki.loader.implement',
 561                         array(
 562                                 $name,
 563                                 new XmlJsCode( "function( $, mw ) {{$scripts}}" ),
 564                                 (object)$styles,
 565                                 (object)$messages
 566                         ) );
 567         }
 568
 569         /**
 570          * Returns JS code which, when called, will register a given list of messages.
 571          *
 572          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 573          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 574          */
 575         public static function makeMessageSetScript( $messages ) {
 576                 return Xml::encodeJsCall( 'mediaWiki.messages.set', array( (object)$messages ) );
 577         }
 578
 579         /**
 580          * Combines an associative array mapping media type to CSS into a
 581          * single stylesheet with @media blocks.
 582          *
 583          * @param $styles Array: List of CSS strings keyed by media type
 584          */
 585         public static function makeCombinedStyles( array $styles ) {
 586                 $out = '';
 587                 foreach ( $styles as $media => $style ) {
 588                         // Transform the media type based on request params and config
 589                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 590                         $media = OutputPage::transformCssMedia( $media );
 591
 592                         if ( $media === null ) {
 593                                 // Skip
 594                         } else if ( $media === '' || $media == 'all' ) {
 595                                 // Don't output invalid or frivolous @media statements
 596                                 $out .= "$style\n";
 597                         } else {
 598                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 599                         }
 600                 }
 601                 return $out;
 602         }
 603
 604         /**
 605          * Returns a JS call to mediaWiki.loader.state, which sets the state of a
 606          * module or modules to a given value. Has two calling conventions:
 607          *
 608          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 609          *         Set the state of a single module called $name to $state
 610          *
 611          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 612          *         Set the state of modules with the given names to the given states
 613          */
 614         public static function makeLoaderStateScript( $name, $state = null ) {
 615                 if ( is_array( $name ) ) {
 616                         return Xml::encodeJsCall( 'mediaWiki.loader.state', array( $name ) );
 617                 } else {
 618                         return Xml::encodeJsCall( 'mediaWiki.loader.state', array( $name, $state ) );
 619                 }
 620         }
 621
 622         /**
 623          * Returns JS code which calls the script given by $script. The script will
 624          * be called with local variables name, version, dependencies and group,
 625          * which will have values corresponding to $name, $version, $dependencies
 626          * and $group as supplied.
 627          *
 628          * @param $name String: Module name
 629          * @param $version Integer: Module version number as a timestamp
 630          * @param $dependencies Array: List of module names on which this module depends
 631          * @param $group String: Group which the module is in.
 632          * @param $script String: JavaScript code
 633          */
 634         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $script ) {
 635                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 636                 return Xml::encodeJsCall(
 637                         "( function( name, version, dependencies, group ) {\n\t$script\n} )",
 638                         array( $name, $version, $dependencies, $group ) );
 639         }
 640
 641         /**
 642          * Returns JS code which calls mediaWiki.loader.register with the given
 643          * parameters. Has three calling conventions:
 644          *
 645          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group ):
 646          *       Register a single module.
 647          *
 648          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 649          *       Register modules with the given names.
 650          *
 651          *   - ResourceLoader::makeLoaderRegisterScript( array(
 652          *        array( $name1, $version1, $dependencies1, $group1 ),
 653          *        array( $name2, $version2, $dependencies1, $group2 ),
 654          *        ...
 655          *     ) ):
 656          *        Registers modules with the given names and parameters.
 657          *
 658          * @param $name String: Module name
 659          * @param $version Integer: Module version number as a timestamp
 660          * @param $dependencies Array: List of module names on which this module depends
 661          * @param $group String: group which the module is in.
 662          */
 663         public static function makeLoaderRegisterScript( $name, $version = null,
 664                 $dependencies = null, $group = null )
 665         {
 666                 if ( is_array( $name ) ) {
 667                         return Xml::encodeJsCall( 'mediaWiki.loader.register', array( $name ) );
 668                 } else {
 669                         $version = (int) $version > 1 ? (int) $version : 1;
 670                         return Xml::encodeJsCall( 'mediaWiki.loader.register',
 671                                 array( $name, $version, $dependencies, $group ) );
 672                 }
 673         }
 674
 675         /**
 676          * Returns JS code which runs given JS code if the client-side framework is
 677          * present.
 678          *
 679          * @param $script String: JavaScript code
 680          */
 681         public static function makeLoaderConditionalScript( $script ) {
 682                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 683                 return "if ( window.mediaWiki ) {\n\t$script\n}\n";
 684         }
 685
 686         /**
 687          * Returns JS code which will set the MediaWiki configuration array to
 688          * the given value.
 689          *
 690          * @param $configuration Array: List of configuration values keyed by variable name
 691          */
 692         public static function makeConfigSetScript( array $configuration ) {
 693                 return Xml::encodeJsCall( 'mediaWiki.config.set', array( $configuration ) );
 694         }
 695
 696         /**
 697          * Determine whether debug mode was requested
 698          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
 699          * @return bool
 700          */
 701         public static function inDebugMode() {
 702                 global $wgRequest, $wgResourceLoaderDebug;
 703                 static $retval = null;
 704                 if ( !is_null( $retval ) )
 705                         return $retval;
 706                 return $retval = $wgRequest->getFuzzyBool( 'debug',
 707                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
 708         }
 709 }