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