includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /** @var array */
  39         private static $lessVars = null;
  40
  41         /**
  42          * Module name/ResourceLoaderModule object pairs
  43          * @var array
  44          */
  45         protected $modules = array();
  46
  47         /**
  48          * Associative array mapping module name to info associative array
  49          * @var array
  50          */
  51         protected $moduleInfos = array();
  52
  53         /** @var Config $config */
  54         private $config;
  55
  56         /**
  57          * Associative array mapping framework ids to a list of names of test suite modules
  58          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  59          * @var array
  60          */
  61         protected $testModuleNames = array();
  62
  63         /**
  64          * E.g. array( 'source-id' => 'http://.../load.php' )
  65          * @var array
  66          */
  67         protected $sources = array();
  68
  69         /**
  70          * Errors accumulated during current respond() call.
  71          * @var array
  72          */
  73         protected $errors = array();
  74
  75         /**
  76          * Load information stored in the database about modules.
  77          *
  78          * This method grabs modules dependencies from the database and updates modules
  79          * objects.
  80          *
  81          * This is not inside the module code because it is much faster to
  82          * request all of the information at once than it is to have each module
  83          * requests its own information. This sacrifice of modularity yields a substantial
  84          * performance improvement.
  85          *
  86          * @param array $modules List of module names to preload information for
  87          * @param ResourceLoaderContext $context Context to load the information within
  88          */
  89         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  90                 if ( !count( $modules ) ) {
  91                         // Or else Database*::select() will explode, plus it's cheaper!
  92                         return;
  93                 }
  94                 $dbr = wfGetDB( DB_SLAVE );
  95                 $skin = $context->getSkin();
  96                 $lang = $context->getLanguage();
  97
  98                 // Get file dependency information
  99                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 100                                 'md_module' => $modules,
 101                                 'md_skin' => $skin
 102                         ), __METHOD__
 103                 );
 104
 105                 // Set modules' dependencies
 106                 $modulesWithDeps = array();
 107                 foreach ( $res as $row ) {
 108                         $module = $this->getModule( $row->md_module );
 109                         if ( $module ) {
 110                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 111                                 $modulesWithDeps[] = $row->md_module;
 112                         }
 113                 }
 114
 115                 // Register the absence of a dependency row too
 116                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 117                         $module = $this->getModule( $name );
 118                         if ( $module ) {
 119                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 120                         }
 121                 }
 122
 123                 // Get message blob mtimes. Only do this for modules with messages
 124                 $modulesWithMessages = array();
 125                 foreach ( $modules as $name ) {
 126                         $module = $this->getModule( $name );
 127                         if ( $module && count( $module->getMessages() ) ) {
 128                                 $modulesWithMessages[] = $name;
 129                         }
 130                 }
 131                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 132                 if ( count( $modulesWithMessages ) ) {
 133                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 134                                         'mr_resource' => $modulesWithMessages,
 135                                         'mr_lang' => $lang
 136                                 ), __METHOD__
 137                         );
 138                         foreach ( $res as $row ) {
 139                                 $module = $this->getModule( $row->mr_resource );
 140                                 if ( $module ) {
 141                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 142                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 143                                 }
 144                         }
 145                 }
 146                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 147                         $module = $this->getModule( $name );
 148                         if ( $module ) {
 149                                 $module->setMsgBlobMtime( $lang, 1 );
 150                         }
 151                 }
 152         }
 153
 154         /**
 155          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 156          *
 157          * Available filters are:
 158          *
 159          *    - minify-js \see JavaScriptMinifier::minify
 160          *    - minify-css \see CSSMin::minify
 161          *
 162          * If $data is empty, only contains whitespace or the filter was unknown,
 163          * $data is returned unmodified.
 164          *
 165          * @param string $filter Name of filter to run
 166          * @param string $data Text to filter, such as JavaScript or CSS text
 167          * @param string $cacheReport Whether to include the cache key report
 168          * @return string Filtered data, or a comment containing an error message
 169          */
 170         public function filter( $filter, $data, $cacheReport = true ) {
 171
 172                 // For empty/whitespace-only data or for unknown filters, don't perform
 173                 // any caching or processing
 174                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 175                         return $data;
 176                 }
 177
 178                 // Try for cache hit
 179                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 180                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 181                 $cache = wfGetCache( CACHE_ANYTHING );
 182                 $cacheEntry = $cache->get( $key );
 183                 if ( is_string( $cacheEntry ) ) {
 184                         wfIncrStats( "rl-$filter-cache-hits" );
 185                         return $cacheEntry;
 186                 }
 187
 188                 $result = '';
 189                 // Run the filter - we've already verified one of these will work
 190                 try {
 191                         wfIncrStats( "rl-$filter-cache-misses" );
 192                         switch ( $filter ) {
 193                                 case 'minify-js':
 194                                         $result = JavaScriptMinifier::minify( $data,
 195                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 196                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 197                                         );
 198                                         if ( $cacheReport ) {
 199                                                 $result .= "\n/* cache key: $key */";
 200                                         }
 201                                         break;
 202                                 case 'minify-css':
 203                                         $result = CSSMin::minify( $data );
 204                                         if ( $cacheReport ) {
 205                                                 $result .= "\n/* cache key: $key */";
 206                                         }
 207                                         break;
 208                         }
 209
 210                         // Save filtered text to Memcached
 211                         $cache->set( $key, $result );
 212                 } catch ( Exception $e ) {
 213                         MWExceptionHandler::logException( $e );
 214                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 215                         $this->errors[] = self::formatExceptionNoComment( $e );
 216                 }
 217
 218                 return $result;
 219         }
 220
 221         /* Methods */
 222
 223         /**
 224          * Register core modules and runs registration hooks.
 225          * @param Config|null $config
 226          */
 227         public function __construct( Config $config = null ) {
 228                 global $IP;
 229
 230                 if ( $config === null ) {
 231                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 232                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 233                 }
 234
 235                 $this->config = $config;
 236
 237                 // Add 'local' source first
 238                 $this->addSource( 'local', wfScript( 'load' ) );
 239
 240                 // Add other sources
 241                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 242
 243                 // Register core modules
 244                 $this->register( include "$IP/resources/Resources.php" );
 245                 // Register extension modules
 246                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 247                 $this->register( $config->get( 'ResourceModules' ) );
 248
 249                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 250                         $this->registerTestModules();
 251                 }
 252
 253         }
 254
 255         /**
 256          * @return Config
 257          */
 258         public function getConfig() {
 259                 return $this->config;
 260         }
 261
 262         /**
 263          * Register a module with the ResourceLoader system.
 264          *
 265          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 266          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 267          *   this may also be a ResourceLoaderModule object. Optional when using
 268          *   multiple-registration calling style.
 269          * @throws MWException If a duplicate module registration is attempted
 270          * @throws MWException If a module name contains illegal characters (pipes or commas)
 271          * @throws MWException If something other than a ResourceLoaderModule is being registered
 272          * @return bool False if there were any errors, in which case one or more modules were
 273          *   not registered
 274          */
 275         public function register( $name, $info = null ) {
 276
 277                 // Allow multiple modules to be registered in one call
 278                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 279                 foreach ( $registrations as $name => $info ) {
 280                         // Disallow duplicate registrations
 281                         if ( isset( $this->moduleInfos[$name] ) ) {
 282                                 // A module has already been registered by this name
 283                                 throw new MWException(
 284                                         'ResourceLoader duplicate registration error. ' .
 285                                         'Another module has already been registered as ' . $name
 286                                 );
 287                         }
 288
 289                         // Check $name for validity
 290                         if ( !self::isValidModuleName( $name ) ) {
 291                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 292                                         . "see ResourceLoader::isValidModuleName()" );
 293                         }
 294
 295                         // Attach module
 296                         if ( $info instanceof ResourceLoaderModule ) {
 297                                 $this->moduleInfos[$name] = array( 'object' => $info );
 298                                 $info->setName( $name );
 299                                 $this->modules[$name] = $info;
 300                         } elseif ( is_array( $info ) ) {
 301                                 // New calling convention
 302                                 $this->moduleInfos[$name] = $info;
 303                         } else {
 304                                 throw new MWException(
 305                                         'ResourceLoader module info type error for module \'' . $name .
 306                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 307                                 );
 308                         }
 309
 310                         // Last-minute changes
 311
 312                         // Apply custom skin-defined styles to existing modules.
 313                         if ( $this->isFileModule( $name ) ) {
 314                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 315                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 316                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 317                                                 continue;
 318                                         }
 319
 320                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 321                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 322                                         if ( isset( $skinStyles[$name] ) ) {
 323                                                 $paths = (array)$skinStyles[$name];
 324                                                 $styleFiles = array();
 325                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 326                                                 $paths = (array)$skinStyles['+' . $name];
 327                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 328                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 329                                                         array();
 330                                         } else {
 331                                                 continue;
 332                                         }
 333
 334                                         // Add new file paths, remapping them to refer to our directories and not use settings
 335                                         // from the module we're modifying. These can come from the base definition or be defined
 336                                         // for each module.
 337                                         list( $localBasePath, $remoteBasePath ) =
 338                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 339                                         list( $localBasePath, $remoteBasePath ) =
 340                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 341
 342                                         foreach ( $paths as $path ) {
 343                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 344                                         }
 345
 346                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 347                                 }
 348                         }
 349                 }
 350
 351         }
 352
 353         /**
 354          */
 355         public function registerTestModules() {
 356                 global $IP;
 357
 358                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 359                         throw new MWException( 'Attempt to register JavaScript test modules '
 360                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 361                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 362                 }
 363
 364                 // Get core test suites
 365                 $testModules = array();
 366                 $testModules['qunit'] = array();
 367                 // Get other test suites (e.g. from extensions)
 368                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 369
 370                 // Add the testrunner (which configures QUnit) to the dependencies.
 371                 // Since it must be ready before any of the test suites are executed.
 372                 foreach ( $testModules['qunit'] as &$module ) {
 373                         // Make sure all test modules are top-loading so that when QUnit starts
 374                         // on document-ready, it will run once and finish. If some tests arrive
 375                         // later (possibly after QUnit has already finished) they will be ignored.
 376                         $module['position'] = 'top';
 377                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 378                 }
 379
 380                 $testModules['qunit'] =
 381                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 382
 383                 foreach ( $testModules as $id => $names ) {
 384                         // Register test modules
 385                         $this->register( $testModules[$id] );
 386
 387                         // Keep track of their names so that they can be loaded together
 388                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 389                 }
 390
 391         }
 392
 393         /**
 394          * Add a foreign source of modules.
 395          *
 396          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 397          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 398          *  backwards-compatibility.
 399          * @throws MWException
 400          */
 401         public function addSource( $id, $loadUrl = null ) {
 402                 // Allow multiple sources to be registered in one call
 403                 if ( is_array( $id ) ) {
 404                         foreach ( $id as $key => $value ) {
 405                                 $this->addSource( $key, $value );
 406                         }
 407                         return;
 408                 }
 409
 410                 // Disallow duplicates
 411                 if ( isset( $this->sources[$id] ) ) {
 412                         throw new MWException(
 413                                 'ResourceLoader duplicate source addition error. ' .
 414                                 'Another source has already been registered as ' . $id
 415                         );
 416                 }
 417
 418                 // Pre 1.24 backwards-compatibility
 419                 if ( is_array( $loadUrl ) ) {
 420                         if ( !isset( $loadUrl['loadScript'] ) ) {
 421                                 throw new MWException(
 422                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 423                                 );
 424                         }
 425
 426                         $loadUrl = $loadUrl['loadScript'];
 427                 }
 428
 429                 $this->sources[$id] = $loadUrl;
 430         }
 431
 432         /**
 433          * Get a list of module names.
 434          *
 435          * @return array List of module names
 436          */
 437         public function getModuleNames() {
 438                 return array_keys( $this->moduleInfos );
 439         }
 440
 441         /**
 442          * Get a list of test module names for one (or all) frameworks.
 443          *
 444          * If the given framework id is unknkown, or if the in-object variable is not an array,
 445          * then it will return an empty array.
 446          *
 447          * @param string $framework Get only the test module names for one
 448          *   particular framework (optional)
 449          * @return array
 450          */
 451         public function getTestModuleNames( $framework = 'all' ) {
 452                 /** @todo api siteinfo prop testmodulenames modulenames */
 453                 if ( $framework == 'all' ) {
 454                         return $this->testModuleNames;
 455                 } elseif ( isset( $this->testModuleNames[$framework] )
 456                         && is_array( $this->testModuleNames[$framework] )
 457                 ) {
 458                         return $this->testModuleNames[$framework];
 459                 } else {
 460                         return array();
 461                 }
 462         }
 463
 464         /**
 465          * Check whether a ResourceLoader module is registered
 466          *
 467          * @since 1.25
 468          * @param string $name
 469          * @return bool
 470          */
 471         public function isModuleRegistered( $name ) {
 472                 return isset( $this->moduleInfos[$name] );
 473         }
 474
 475         /**
 476          * Get the ResourceLoaderModule object for a given module name.
 477          *
 478          * If an array of module parameters exists but a ResourceLoaderModule object has not
 479          * yet been instantiated, this method will instantiate and cache that object such that
 480          * subsequent calls simply return the same object.
 481          *
 482          * @param string $name Module name
 483          * @return ResourceLoaderModule|null If module has been registered, return a
 484          *  ResourceLoaderModule instance. Otherwise, return null.
 485          */
 486         public function getModule( $name ) {
 487                 if ( !isset( $this->modules[$name] ) ) {
 488                         if ( !isset( $this->moduleInfos[$name] ) ) {
 489                                 // No such module
 490                                 return null;
 491                         }
 492                         // Construct the requested object
 493                         $info = $this->moduleInfos[$name];
 494                         /** @var ResourceLoaderModule $object */
 495                         if ( isset( $info['object'] ) ) {
 496                                 // Object given in info array
 497                                 $object = $info['object'];
 498                         } else {
 499                                 if ( !isset( $info['class'] ) ) {
 500                                         $class = 'ResourceLoaderFileModule';
 501                                 } else {
 502                                         $class = $info['class'];
 503                                 }
 504                                 /** @var ResourceLoaderModule $object */
 505                                 $object = new $class( $info );
 506                                 $object->setConfig( $this->getConfig() );
 507                         }
 508                         $object->setName( $name );
 509                         $this->modules[$name] = $object;
 510                 }
 511
 512                 return $this->modules[$name];
 513         }
 514
 515         /**
 516          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 517          *
 518          * @param string $name Module name
 519          * @return bool
 520          */
 521         protected function isFileModule( $name ) {
 522                 if ( !isset( $this->moduleInfos[$name] ) ) {
 523                         return false;
 524                 }
 525                 $info = $this->moduleInfos[$name];
 526                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 527                         return false;
 528                 }
 529                 return true;
 530         }
 531
 532         /**
 533          * Get the list of sources.
 534          *
 535          * @return array Like array( id => load.php url, .. )
 536          */
 537         public function getSources() {
 538                 return $this->sources;
 539         }
 540
 541         /**
 542          * Get the URL to the load.php endpoint for the given
 543          * ResourceLoader source
 544          *
 545          * @since 1.24
 546          * @param string $source
 547          * @throws MWException On an invalid $source name
 548          * @return string
 549          */
 550         public function getLoadScript( $source ) {
 551                 if ( !isset( $this->sources[$source] ) ) {
 552                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 553                 }
 554                 return $this->sources[$source];
 555         }
 556
 557         /**
 558          * Output a response to a load request, including the content-type header.
 559          *
 560          * @param ResourceLoaderContext $context Context in which a response should be formed
 561          */
 562         public function respond( ResourceLoaderContext $context ) {
 563                 // Use file cache if enabled and available...
 564                 if ( $this->config->get( 'UseFileCache' ) ) {
 565                         $fileCache = ResourceFileCache::newFromContext( $context );
 566                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 567                                 return; // output handled
 568                         }
 569                 }
 570
 571                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 572                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 573                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 574                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 575                 // the whole thing in our own output buffer to be sure the active buffer
 576                 // doesn't use ob_gzhandler.
 577                 // See http://bugs.php.net/bug.php?id=36514
 578                 ob_start();
 579
 580                 // Find out which modules are missing and instantiate the others
 581                 $modules = array();
 582                 $missing = array();
 583                 foreach ( $context->getModules() as $name ) {
 584                         $module = $this->getModule( $name );
 585                         if ( $module ) {
 586                                 // Do not allow private modules to be loaded from the web.
 587                                 // This is a security issue, see bug 34907.
 588                                 if ( $module->getGroup() === 'private' ) {
 589                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 590                                         $this->errors[] = "Cannot show private module \"$name\"";
 591                                         continue;
 592                                 }
 593                                 $modules[$name] = $module;
 594                         } else {
 595                                 $missing[] = $name;
 596                         }
 597                 }
 598
 599                 // Preload information needed to the mtime calculation below
 600                 try {
 601                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 602                 } catch ( Exception $e ) {
 603                         MWExceptionHandler::logException( $e );
 604                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 605                         $this->errors[] = self::formatExceptionNoComment( $e );
 606                 }
 607
 608                 // To send Last-Modified and support If-Modified-Since, we need to detect
 609                 // the last modified time
 610                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 611                 foreach ( $modules as $module ) {
 612                         /**
 613                          * @var $module ResourceLoaderModule
 614                          */
 615                         try {
 616                                 // Calculate maximum modified time
 617                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 618                         } catch ( Exception $e ) {
 619                                 MWExceptionHandler::logException( $e );
 620                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 621                                 $this->errors[] = self::formatExceptionNoComment( $e );
 622                         }
 623                 }
 624
 625                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 626                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 627                         return; // output handled (buffers cleared)
 628                 }
 629
 630                 // Generate a response
 631                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 632
 633                 // Capture any PHP warnings from the output buffer and append them to the
 634                 // error list if we're in debug mode.
 635                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 636                         $this->errors[] = $warnings;
 637                 }
 638
 639                 // Save response to file cache unless there are errors
 640                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 641                         // Cache single modules and images...and other requests if there are enough hits
 642                         if ( ResourceFileCache::useFileCache( $context ) ) {
 643                                 if ( $fileCache->isCacheWorthy() ) {
 644                                         $fileCache->saveText( $response );
 645                                 } else {
 646                                         $fileCache->incrMissesRecent( $context->getRequest() );
 647                                 }
 648                         }
 649                 }
 650
 651                 // Send content type and cache related headers
 652                 $this->sendResponseHeaders( $context, $mtime, (bool)$this->errors );
 653
 654                 // Remove the output buffer and output the response
 655                 ob_end_clean();
 656
 657                 if ( $context->getImageObj() && $this->errors ) {
 658                         // We can't show both the error messages and the response when it's an image.
 659                         $errorText = '';
 660                         foreach ( $this->errors as $error ) {
 661                                 $errorText .= $error . "\n";
 662                         }
 663                         $response = $errorText;
 664                 } elseif ( $this->errors ) {
 665                         // Prepend comments indicating errors
 666                         $errorText = '';
 667                         foreach ( $this->errors as $error ) {
 668                                 $errorText .= self::makeComment( $error );
 669                         }
 670                         $response = $errorText . $response;
 671                 }
 672
 673                 $this->errors = array();
 674                 echo $response;
 675
 676         }
 677
 678         /**
 679          * Send content type and last modified headers to the client.
 680          * @param ResourceLoaderContext $context
 681          * @param string $mtime TS_MW timestamp to use for last-modified
 682          * @param bool $errors Whether there are errors in the response
 683          * @return void
 684          */
 685         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 686                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 687                 // If a version wasn't specified we need a shorter expiry time for updates
 688                 // to propagate to clients quickly
 689                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 690                 if ( is_null( $context->getVersion() ) || $errors ) {
 691                         $maxage = $rlMaxage['unversioned']['client'];
 692                         $smaxage = $rlMaxage['unversioned']['server'];
 693                 // If a version was specified we can use a longer expiry time since changing
 694                 // version numbers causes cache misses
 695                 } else {
 696                         $maxage = $rlMaxage['versioned']['client'];
 697                         $smaxage = $rlMaxage['versioned']['server'];
 698                 }
 699                 if ( $context->getImageObj() ) {
 700                         // Output different headers if we're outputting textual errors.
 701                         if ( $errors ) {
 702                                 header( 'Content-Type: text/plain; charset=utf-8' );
 703                         } else {
 704                                 $context->getImageObj()->sendResponseHeaders( $context );
 705                         }
 706                 } elseif ( $context->getOnly() === 'styles' ) {
 707                         header( 'Content-Type: text/css; charset=utf-8' );
 708                         header( 'Access-Control-Allow-Origin: *' );
 709                 } else {
 710                         header( 'Content-Type: text/javascript; charset=utf-8' );
 711                 }
 712                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 713                 if ( $context->getDebug() ) {
 714                         // Do not cache debug responses
 715                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 716                         header( 'Pragma: no-cache' );
 717                 } else {
 718                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 719                         $exp = min( $maxage, $smaxage );
 720                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 721                 }
 722         }
 723
 724         /**
 725          * Respond with 304 Last Modified if appropiate.
 726          *
 727          * If there's an If-Modified-Since header, respond with a 304 appropriately
 728          * and clear out the output buffer. If the client cache is too old then do nothing.
 729          *
 730          * @param ResourceLoaderContext $context
 731          * @param string $mtime The TS_MW timestamp to check the header against
 732          * @return bool True if 304 header sent and output handled
 733          */
 734         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 735                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 736                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 737                 // so we get a valid timestamp.
 738                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 739                 // Never send 304s in debug mode
 740                 if ( $ims !== false && !$context->getDebug() ) {
 741                         $imsTS = strtok( $ims, ';' );
 742                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 743                                 // There's another bug in ob_gzhandler (see also the comment at
 744                                 // the top of this function) that causes it to gzip even empty
 745                                 // responses, meaning it's impossible to produce a truly empty
 746                                 // response (because the gzip header is always there). This is
 747                                 // a problem because 304 responses have to be completely empty
 748                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 749                                 // See also http://bugs.php.net/bug.php?id=51579
 750                                 // To work around this, we tear down all output buffering before
 751                                 // sending the 304.
 752                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 753
 754                                 header( 'HTTP/1.0 304 Not Modified' );
 755                                 header( 'Status: 304 Not Modified' );
 756                                 return true;
 757                         }
 758                 }
 759                 return false;
 760         }
 761
 762         /**
 763          * Send out code for a response from file cache if possible.
 764          *
 765          * @param ResourceFileCache $fileCache Cache object for this request URL
 766          * @param ResourceLoaderContext $context Context in which to generate a response
 767          * @return bool If this found a cache file and handled the response
 768          */
 769         protected function tryRespondFromFileCache(
 770                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 771         ) {
 772                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 773                 // Buffer output to catch warnings.
 774                 ob_start();
 775                 // Get the maximum age the cache can be
 776                 $maxage = is_null( $context->getVersion() )
 777                         ? $rlMaxage['unversioned']['server']
 778                         : $rlMaxage['versioned']['server'];
 779                 // Minimum timestamp the cache file must have
 780                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 781                 if ( !$good ) {
 782                         try { // RL always hits the DB on file cache miss...
 783                                 wfGetDB( DB_SLAVE );
 784                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 785                                 $good = $fileCache->isCacheGood(); // cache existence check
 786                         }
 787                 }
 788                 if ( $good ) {
 789                         $ts = $fileCache->cacheTimestamp();
 790                         // Send content type and cache headers
 791                         $this->sendResponseHeaders( $context, $ts, false );
 792                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 793                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 794                                 return false; // output handled (buffers cleared)
 795                         }
 796                         $response = $fileCache->fetchText();
 797                         // Capture any PHP warnings from the output buffer and append them to the
 798                         // response in a comment if we're in debug mode.
 799                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 800                                 $response = "/*\n$warnings\n*/\n" . $response;
 801                         }
 802                         // Remove the output buffer and output the response
 803                         ob_end_clean();
 804                         echo $response . "\n/* Cached {$ts} */";
 805                         return true; // cache hit
 806                 }
 807                 // Clear buffer
 808                 ob_end_clean();
 809
 810                 return false; // cache miss
 811         }
 812
 813         /**
 814          * Generate a CSS or JS comment block.
 815          *
 816          * Only use this for public data, not error message details.
 817          *
 818          * @param string $text
 819          * @return string
 820          */
 821         public static function makeComment( $text ) {
 822                 $encText = str_replace( '*/', '* /', $text );
 823                 return "/*\n$encText\n*/\n";
 824         }
 825
 826         /**
 827          * Handle exception display.
 828          *
 829          * @param Exception $e Exception to be shown to the user
 830          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 831          */
 832         public static function formatException( $e ) {
 833                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 834         }
 835
 836         /**
 837          * Handle exception display.
 838          *
 839          * @since 1.25
 840          * @param Exception $e Exception to be shown to the user
 841          * @return string Sanitized text that can be returned to the user
 842          */
 843         protected static function formatExceptionNoComment( $e ) {
 844                 global $wgShowExceptionDetails;
 845
 846                 if ( $wgShowExceptionDetails ) {
 847                         return $e->__toString();
 848                 } else {
 849                         return wfMessage( 'internalerror' )->text();
 850                 }
 851         }
 852
 853         /**
 854          * Generate code for a response.
 855          *
 856          * @param ResourceLoaderContext $context Context in which to generate a response
 857          * @param array $modules List of module objects keyed by module name
 858          * @param array $missing List of requested module names that are unregistered (optional)
 859          * @return string Response data
 860          */
 861         public function makeModuleResponse( ResourceLoaderContext $context,
 862                 array $modules, array $missing = array()
 863         ) {
 864                 $out = '';
 865                 $states = array();
 866
 867                 if ( !count( $modules ) && !count( $missing ) ) {
 868                         return <<<MESSAGE
 869 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 870    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 871    no modules were requested. Max made me put this here. */
 872 MESSAGE;
 873                 }
 874
 875                 $image = $context->getImageObj();
 876                 if ( $image ) {
 877                         $data = $image->getImageData( $context );
 878                         if ( $data === false ) {
 879                                 $data = '';
 880                                 $this->errors[] = 'Image generation failed';
 881                         }
 882                         return $data;
 883                 }
 884
 885                 // Pre-fetch blobs
 886                 if ( $context->shouldIncludeMessages() ) {
 887                         try {
 888                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 889                         } catch ( Exception $e ) {
 890                                 MWExceptionHandler::logException( $e );
 891                                 wfDebugLog(
 892                                         'resourceloader',
 893                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 894                                 );
 895                                 $this->errors[] = self::formatExceptionNoComment( $e );
 896                         }
 897                 } else {
 898                         $blobs = array();
 899                 }
 900
 901                 foreach ( $missing as $name ) {
 902                         $states[$name] = 'missing';
 903                 }
 904
 905                 // Generate output
 906                 $isRaw = false;
 907                 foreach ( $modules as $name => $module ) {
 908                         /**
 909                          * @var $module ResourceLoaderModule
 910                          */
 911
 912                         try {
 913                                 $scripts = '';
 914                                 if ( $context->shouldIncludeScripts() ) {
 915                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 916                                         // However, we can't do this if the module doesn't support it
 917                                         // We also can't do this if there is an only= parameter, because we have to give
 918                                         // the module a way to return a load.php URL without causing an infinite loop
 919                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 920                                                 $scripts = $module->getScriptURLsForDebug( $context );
 921                                         } else {
 922                                                 $scripts = $module->getScript( $context );
 923                                                 // rtrim() because there are usually a few line breaks
 924                                                 // after the last ';'. A new line at EOF, a new line
 925                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 926                                                 if ( is_string( $scripts )
 927                                                         && strlen( $scripts )
 928                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 929                                                 ) {
 930                                                         // Append semicolon to prevent weird bugs caused by files not
 931                                                         // terminating their statements right (bug 27054)
 932                                                         $scripts .= ";\n";
 933                                                 }
 934                                         }
 935                                 }
 936                                 // Styles
 937                                 $styles = array();
 938                                 if ( $context->shouldIncludeStyles() ) {
 939                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 940                                         // that don't *have* any stylesheets (bug 38024).
 941                                         $stylePairs = $module->getStyles( $context );
 942                                         if ( count( $stylePairs ) ) {
 943                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 944                                                 // See comment near shouldIncludeScripts() for more details
 945                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 946                                                         $styles = array(
 947                                                                 'url' => $module->getStyleURLsForDebug( $context )
 948                                                         );
 949                                                 } else {
 950                                                         // Minify CSS before embedding in mw.loader.implement call
 951                                                         // (unless in debug mode)
 952                                                         if ( !$context->getDebug() ) {
 953                                                                 foreach ( $stylePairs as $media => $style ) {
 954                                                                         // Can be either a string or an array of strings.
 955                                                                         if ( is_array( $style ) ) {
 956                                                                                 $stylePairs[$media] = array();
 957                                                                                 foreach ( $style as $cssText ) {
 958                                                                                         if ( is_string( $cssText ) ) {
 959                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 960                                                                                         }
 961                                                                                 }
 962                                                                         } elseif ( is_string( $style ) ) {
 963                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 964                                                                         }
 965                                                                 }
 966                                                         }
 967                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 968                                                         $styles = array(
 969                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 970                                                         );
 971                                                 }
 972                                         }
 973                                 }
 974
 975                                 // Messages
 976                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 977
 978                                 // Append output
 979                                 switch ( $context->getOnly() ) {
 980                                         case 'scripts':
 981                                                 if ( is_string( $scripts ) ) {
 982                                                         // Load scripts raw...
 983                                                         $out .= $scripts;
 984                                                 } elseif ( is_array( $scripts ) ) {
 985                                                         // ...except when $scripts is an array of URLs
 986                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 987                                                 }
 988                                                 break;
 989                                         case 'styles':
 990                                                 // We no longer seperate into media, they are all combined now with
 991                                                 // custom media type groups into @media .. {} sections as part of the css string.
 992                                                 // Module returns either an empty array or a numerical array with css strings.
 993                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 994                                                 break;
 995                                         case 'messages':
 996                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 997                                                 break;
 998                                         case 'templates':
 999                                                 $out .= Xml::encodeJsCall(
1000                                                         'mw.templates.set',
1001                                                         array( $name, (object)$module->getTemplates() ),
1002                                                         ResourceLoader::inDebugMode()
1003                                                 );
1004                                                 break;
1005                                         default:
1006                                                 $out .= self::makeLoaderImplementScript(
1007                                                         $name,
1008                                                         $scripts,
1009                                                         $styles,
1010                                                         new XmlJsCode( $messagesBlob ),
1011                                                         $module->getTemplates()
1012                                                 );
1013                                                 break;
1014                                 }
1015                         } catch ( Exception $e ) {
1016                                 MWExceptionHandler::logException( $e );
1017                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1018                                 $this->errors[] = self::formatExceptionNoComment( $e );
1019
1020                                 // Respond to client with error-state instead of module implementation
1021                                 $states[$name] = 'error';
1022                                 unset( $modules[$name] );
1023                         }
1024                         $isRaw |= $module->isRaw();
1025                 }
1026
1027                 // Update module states
1028                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1029                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1030                                 // Set the state of modules loaded as only scripts to ready as
1031                                 // they don't have an mw.loader.implement wrapper that sets the state
1032                                 foreach ( $modules as $name => $module ) {
1033                                         $states[$name] = 'ready';
1034                                 }
1035                         }
1036
1037                         // Set the state of modules we didn't respond to with mw.loader.implement
1038                         if ( count( $states ) ) {
1039                                 $out .= self::makeLoaderStateScript( $states );
1040                         }
1041                 } else {
1042                         if ( count( $states ) ) {
1043                                 $this->errors[] = 'Problematic modules: ' .
1044                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1045                         }
1046                 }
1047
1048                 if ( !$context->getDebug() ) {
1049                         if ( $context->getOnly() === 'styles' ) {
1050                                 $out = $this->filter( 'minify-css', $out );
1051                         } else {
1052                                 $out = $this->filter( 'minify-js', $out );
1053                         }
1054                 }
1055
1056                 return $out;
1057         }
1058
1059         /* Static Methods */
1060
1061         /**
1062          * Return JS code that calls mw.loader.implement with given module properties.
1063          *
1064          * @param string $name Module name
1065          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1066          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1067          *   to CSS files keyed by media type
1068          * @param mixed $messages List of messages associated with this module. May either be an
1069          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1070          *   the same data, wrapped in an XmlJsCode object.
1071          * @param array $templates Keys are name of templates and values are the source of
1072          *   the template.
1073          * @throws MWException
1074          * @return string
1075          */
1076         public static function makeLoaderImplementScript( $name, $scripts, $styles,
1077                 $messages, $templates
1078         ) {
1079                 if ( is_string( $scripts ) ) {
1080                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1081                 } elseif ( !is_array( $scripts ) ) {
1082                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1083                 }
1084
1085                 return Xml::encodeJsCall(
1086                         'mw.loader.implement',
1087                         array(
1088                                 $name,
1089                                 $scripts,
1090                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1091                                 // Although these variables are associative arrays, which become javascript
1092                                 // objects through json_encode. In many cases they will be empty arrays, and
1093                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1094                                 // output javascript "[]" instead of "{}". This fixes that.
1095                                 (object)$styles,
1096                                 (object)$messages,
1097                                 (object)$templates,
1098                         ),
1099                         ResourceLoader::inDebugMode()
1100                 );
1101         }
1102
1103         /**
1104          * Returns JS code which, when called, will register a given list of messages.
1105          *
1106          * @param mixed $messages Either an associative array mapping message key to value, or a
1107          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1108          * @return string
1109          */
1110         public static function makeMessageSetScript( $messages ) {
1111                 return Xml::encodeJsCall(
1112                         'mw.messages.set',
1113                         array( (object)$messages ),
1114                         ResourceLoader::inDebugMode()
1115                 );
1116         }
1117
1118         /**
1119          * Combines an associative array mapping media type to CSS into a
1120          * single stylesheet with "@media" blocks.
1121          *
1122          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1123          * @return array
1124          */
1125         public static function makeCombinedStyles( array $stylePairs ) {
1126                 $out = array();
1127                 foreach ( $stylePairs as $media => $styles ) {
1128                         // ResourceLoaderFileModule::getStyle can return the styles
1129                         // as a string or an array of strings. This is to allow separation in
1130                         // the front-end.
1131                         $styles = (array)$styles;
1132                         foreach ( $styles as $style ) {
1133                                 $style = trim( $style );
1134                                 // Don't output an empty "@media print { }" block (bug 40498)
1135                                 if ( $style !== '' ) {
1136                                         // Transform the media type based on request params and config
1137                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1138                                         $media = OutputPage::transformCssMedia( $media );
1139
1140                                         if ( $media === '' || $media == 'all' ) {
1141                                                 $out[] = $style;
1142                                         } elseif ( is_string( $media ) ) {
1143                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1144                                         }
1145                                         // else: skip
1146                                 }
1147                         }
1148                 }
1149                 return $out;
1150         }
1151
1152         /**
1153          * Returns a JS call to mw.loader.state, which sets the state of a
1154          * module or modules to a given value. Has two calling conventions:
1155          *
1156          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1157          *         Set the state of a single module called $name to $state
1158          *
1159          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1160          *         Set the state of modules with the given names to the given states
1161          *
1162          * @param string $name
1163          * @param string $state
1164          * @return string
1165          */
1166         public static function makeLoaderStateScript( $name, $state = null ) {
1167                 if ( is_array( $name ) ) {
1168                         return Xml::encodeJsCall(
1169                                 'mw.loader.state',
1170                                 array( $name ),
1171                                 ResourceLoader::inDebugMode()
1172                         );
1173                 } else {
1174                         return Xml::encodeJsCall(
1175                                 'mw.loader.state',
1176                                 array( $name, $state ),
1177                                 ResourceLoader::inDebugMode()
1178                         );
1179                 }
1180         }
1181
1182         /**
1183          * Returns JS code which calls the script given by $script. The script will
1184          * be called with local variables name, version, dependencies and group,
1185          * which will have values corresponding to $name, $version, $dependencies
1186          * and $group as supplied.
1187          *
1188          * @param string $name Module name
1189          * @param int $version Module version number as a timestamp
1190          * @param array $dependencies List of module names on which this module depends
1191          * @param string $group Group which the module is in.
1192          * @param string $source Source of the module, or 'local' if not foreign.
1193          * @param string $script JavaScript code
1194          * @return string
1195          */
1196         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1197                 $group, $source, $script
1198         ) {
1199                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1200                 return Xml::encodeJsCall(
1201                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1202                         array( $name, $version, $dependencies, $group, $source ),
1203                         ResourceLoader::inDebugMode()
1204                 );
1205         }
1206
1207         /**
1208          * Remove empty values from the end of an array.
1209          *
1210          * Values considered empty:
1211          *
1212          * - null
1213          * - empty array
1214          *
1215          * @param Array $array
1216          */
1217         private static function trimArray( Array &$array ) {
1218                 $i = count( $array );
1219                 while ( $i-- ) {
1220                         if ( $array[$i] === null || $array[$i] === array() ) {
1221                                 unset( $array[$i] );
1222                         } else {
1223                                 break;
1224                         }
1225                 }
1226         }
1227
1228         /**
1229          * Returns JS code which calls mw.loader.register with the given
1230          * parameters. Has three calling conventions:
1231          *
1232          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1233          *        $dependencies, $group, $source, $skip
1234          *     ):
1235          *        Register a single module.
1236          *
1237          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1238          *        Register modules with the given names.
1239          *
1240          *   - ResourceLoader::makeLoaderRegisterScript( array(
1241          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1242          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1243          *        ...
1244          *     ) ):
1245          *        Registers modules with the given names and parameters.
1246          *
1247          * @param string $name Module name
1248          * @param int $version Module version number as a timestamp
1249          * @param array $dependencies List of module names on which this module depends
1250          * @param string $group Group which the module is in
1251          * @param string $source Source of the module, or 'local' if not foreign
1252          * @param string $skip Script body of the skip function
1253          * @return string
1254          */
1255         public static function makeLoaderRegisterScript( $name, $version = null,
1256                 $dependencies = null, $group = null, $source = null, $skip = null
1257         ) {
1258                 if ( is_array( $name ) ) {
1259                         // Build module name index
1260                         $index = array();
1261                         foreach ( $name as $i => &$module ) {
1262                                 $index[$module[0]] = $i;
1263                         }
1264
1265                         // Transform dependency names into indexes when possible, they will be resolved by
1266                         // mw.loader.register on the other end
1267                         foreach ( $name as &$module ) {
1268                                 if ( isset( $module[2] ) ) {
1269                                         foreach ( $module[2] as &$dependency ) {
1270                                                 if ( isset( $index[$dependency] ) ) {
1271                                                         $dependency = $index[$dependency];
1272                                                 }
1273                                         }
1274                                 }
1275                         }
1276
1277                         array_walk( $name, array( 'self', 'trimArray' ) );
1278
1279                         return Xml::encodeJsCall(
1280                                 'mw.loader.register',
1281                                 array( $name ),
1282                                 ResourceLoader::inDebugMode()
1283                         );
1284                 } else {
1285                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1286                         self::trimArray( $registration );
1287                         return Xml::encodeJsCall(
1288                                 'mw.loader.register',
1289                                 $registration,
1290                                 ResourceLoader::inDebugMode()
1291                         );
1292                 }
1293         }
1294
1295         /**
1296          * Returns JS code which calls mw.loader.addSource() with the given
1297          * parameters. Has two calling conventions:
1298          *
1299          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1300          *       Register a single source
1301          *
1302          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1303          *       Register sources with the given IDs and properties.
1304          *
1305          * @param string $id Source ID
1306          * @param array $properties Source properties (see addSource())
1307          * @return string
1308          */
1309         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1310                 if ( is_array( $id ) ) {
1311                         return Xml::encodeJsCall(
1312                                 'mw.loader.addSource',
1313                                 array( $id ),
1314                                 ResourceLoader::inDebugMode()
1315                         );
1316                 } else {
1317                         return Xml::encodeJsCall(
1318                                 'mw.loader.addSource',
1319                                 array( $id, $properties ),
1320                                 ResourceLoader::inDebugMode()
1321                         );
1322                 }
1323         }
1324
1325         /**
1326          * Returns JS code which runs given JS code if the client-side framework is
1327          * present.
1328          *
1329          * @deprecated since 1.25; use makeInlineScript instead
1330          * @param string $script JavaScript code
1331          * @return string
1332          */
1333         public static function makeLoaderConditionalScript( $script ) {
1334                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1335         }
1336
1337         /**
1338          * Construct an inline script tag with given JS code.
1339          *
1340          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1341          * only if the client has adequate support for MediaWiki JavaScript code.
1342          *
1343          * @param string $script JavaScript code
1344          * @return string HTML
1345          */
1346         public static function makeInlineScript( $script ) {
1347                 $js = 'var _mwq = _mwq || []; _mwq.push( function ( mw ) { ' . $script . ' } );';
1348                 return Html::inlineScript( $js );
1349         }
1350
1351         /**
1352          * Returns JS code which will set the MediaWiki configuration array to
1353          * the given value.
1354          *
1355          * @param array $configuration List of configuration values keyed by variable name
1356          * @return string
1357          */
1358         public static function makeConfigSetScript( array $configuration ) {
1359                 return Xml::encodeJsCall(
1360                         'mw.config.set',
1361                         array( $configuration ),
1362                         ResourceLoader::inDebugMode()
1363                 );
1364         }
1365
1366         /**
1367          * Convert an array of module names to a packed query string.
1368          *
1369          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1370          * becomes 'foo.bar,baz|bar.baz,quux'
1371          * @param array $modules List of module names (strings)
1372          * @return string Packed query string
1373          */
1374         public static function makePackedModulesString( $modules ) {
1375                 $groups = array(); // array( prefix => array( suffixes ) )
1376                 foreach ( $modules as $module ) {
1377                         $pos = strrpos( $module, '.' );
1378                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1379                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1380                         $groups[$prefix][] = $suffix;
1381                 }
1382
1383                 $arr = array();
1384                 foreach ( $groups as $prefix => $suffixes ) {
1385                         $p = $prefix === '' ? '' : $prefix . '.';
1386                         $arr[] = $p . implode( ',', $suffixes );
1387                 }
1388                 $str = implode( '|', $arr );
1389                 return $str;
1390         }
1391
1392         /**
1393          * Determine whether debug mode was requested
1394          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1395          * @return bool
1396          */
1397         public static function inDebugMode() {
1398                 if ( self::$debugMode === null ) {
1399                         global $wgRequest, $wgResourceLoaderDebug;
1400                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1401                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1402                         );
1403                 }
1404                 return self::$debugMode;
1405         }
1406
1407         /**
1408          * Reset static members used for caching.
1409          *
1410          * Global state and $wgRequest are evil, but we're using it right
1411          * now and sometimes we need to be able to force ResourceLoader to
1412          * re-evaluate the context because it has changed (e.g. in the test suite).
1413          */
1414         public static function clearCache() {
1415                 self::$debugMode = null;
1416         }
1417
1418         /**
1419          * Build a load.php URL
1420          *
1421          * @since 1.24
1422          * @param string $source Name of the ResourceLoader source
1423          * @param ResourceLoaderContext $context
1424          * @param array $extraQuery
1425          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1426          */
1427         public function createLoaderURL( $source, ResourceLoaderContext $context,
1428                 $extraQuery = array()
1429         ) {
1430                 $query = self::createLoaderQuery( $context, $extraQuery );
1431                 $script = $this->getLoadScript( $source );
1432
1433                 // Prevent the IE6 extension check from being triggered (bug 28840)
1434                 // by appending a character that's invalid in Windows extensions ('*')
1435                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1436         }
1437
1438         /**
1439          * Build a load.php URL
1440          * @deprecated since 1.24, use createLoaderURL instead
1441          * @param array $modules Array of module names (strings)
1442          * @param string $lang Language code
1443          * @param string $skin Skin name
1444          * @param string|null $user User name. If null, the &user= parameter is omitted
1445          * @param string|null $version Versioning timestamp
1446          * @param bool $debug Whether the request should be in debug mode
1447          * @param string|null $only &only= parameter
1448          * @param bool $printable Printable mode
1449          * @param bool $handheld Handheld mode
1450          * @param array $extraQuery Extra query parameters to add
1451          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1452          */
1453         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1454                 $version = null, $debug = false, $only = null, $printable = false,
1455                 $handheld = false, $extraQuery = array()
1456         ) {
1457                 global $wgLoadScript;
1458
1459                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1460                         $only, $printable, $handheld, $extraQuery
1461                 );
1462
1463                 // Prevent the IE6 extension check from being triggered (bug 28840)
1464                 // by appending a character that's invalid in Windows extensions ('*')
1465                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1466         }
1467
1468         /**
1469          * Helper for createLoaderURL()
1470          *
1471          * @since 1.24
1472          * @see makeLoaderQuery
1473          * @param ResourceLoaderContext $context
1474          * @param array $extraQuery
1475          * @return array
1476          */
1477         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1478                 return self::makeLoaderQuery(
1479                         $context->getModules(),
1480                         $context->getLanguage(),
1481                         $context->getSkin(),
1482                         $context->getUser(),
1483                         $context->getVersion(),
1484                         $context->getDebug(),
1485                         $context->getOnly(),
1486                         $context->getRequest()->getBool( 'printable' ),
1487                         $context->getRequest()->getBool( 'handheld' ),
1488                         $extraQuery
1489                 );
1490         }
1491
1492         /**
1493          * Build a query array (array representation of query string) for load.php. Helper
1494          * function for makeLoaderURL().
1495          *
1496          * @param array $modules
1497          * @param string $lang
1498          * @param string $skin
1499          * @param string $user
1500          * @param string $version
1501          * @param bool $debug
1502          * @param string $only
1503          * @param bool $printable
1504          * @param bool $handheld
1505          * @param array $extraQuery
1506          *
1507          * @return array
1508          */
1509         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1510                 $version = null, $debug = false, $only = null, $printable = false,
1511                 $handheld = false, $extraQuery = array()
1512         ) {
1513                 $query = array(
1514                         'modules' => self::makePackedModulesString( $modules ),
1515                         'lang' => $lang,
1516                         'skin' => $skin,
1517                         'debug' => $debug ? 'true' : 'false',
1518                 );
1519                 if ( $user !== null ) {
1520                         $query['user'] = $user;
1521                 }
1522                 if ( $version !== null ) {
1523                         $query['version'] = $version;
1524                 }
1525                 if ( $only !== null ) {
1526                         $query['only'] = $only;
1527                 }
1528                 if ( $printable ) {
1529                         $query['printable'] = 1;
1530                 }
1531                 if ( $handheld ) {
1532                         $query['handheld'] = 1;
1533                 }
1534                 $query += $extraQuery;
1535
1536                 // Make queries uniform in order
1537                 ksort( $query );
1538                 return $query;
1539         }
1540
1541         /**
1542          * Check a module name for validity.
1543          *
1544          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1545          * at most 255 bytes.
1546          *
1547          * @param string $moduleName Module name to check
1548          * @return bool Whether $moduleName is a valid module name
1549          */
1550         public static function isValidModuleName( $moduleName ) {
1551                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1552         }
1553
1554         /**
1555          * Returns LESS compiler set up for use with MediaWiki
1556          *
1557          * @param Config $config
1558          * @throws MWException
1559          * @since 1.22
1560          * @return lessc
1561          */
1562         public static function getLessCompiler( Config $config ) {
1563                 // When called from the installer, it is possible that a required PHP extension
1564                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1565                 // exception (caught by the installer) to prevent a fatal error later on.
1566                 if ( !class_exists( 'lessc' ) ) {
1567                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1568                 }
1569                 if ( !function_exists( 'ctype_digit' ) ) {
1570                         throw new MWException( 'lessc requires the Ctype extension' );
1571                 }
1572
1573                 $less = new lessc();
1574                 $less->setPreserveComments( true );
1575                 $less->setVariables( self::getLessVars( $config ) );
1576                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1577                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1578                         $less->registerFunction( $name, $func );
1579                 }
1580                 return $less;
1581         }
1582
1583         /**
1584          * Get global LESS variables.
1585          *
1586          * @param Config $config
1587          * @since 1.22
1588          * @return array Map of variable names to string CSS values.
1589          */
1590         public static function getLessVars( Config $config ) {
1591                 if ( !self::$lessVars ) {
1592                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1593                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1594                         // Sort by key to ensure consistent hashing for cache lookups.
1595                         ksort( $lessVars );
1596                         self::$lessVars = $lessVars;
1597                 }
1598                 return self::$lessVars;
1599         }
1600 }