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 array */
  36         protected static $requiredSourceProperties = array( 'loadScript' );
  37
  38         /** @var bool */
  39         protected static $debugMode = null;
  40
  41         /** @var array Module name/ResourceLoaderModule object pairs */
  42         protected $modules = array();
  43
  44         /** @var array Associative array mapping module name to info associative array */
  45         protected $moduleInfos = array();
  46
  47         /** @var Config $config */
  48         private $config;
  49
  50         /**
  51          * @var array Associative array mapping framework ids to a list of names of test suite modules
  52          *      like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  53          */
  54         protected $testModuleNames = array();
  55
  56         /** @var array E.g. array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) */
  57         protected $sources = array();
  58
  59         /** @var bool */
  60         protected $hasErrors = false;
  61
  62         /**
  63          * Load information stored in the database about modules.
  64          *
  65          * This method grabs modules dependencies from the database and updates modules
  66          * objects.
  67          *
  68          * This is not inside the module code because it is much faster to
  69          * request all of the information at once than it is to have each module
  70          * requests its own information. This sacrifice of modularity yields a substantial
  71          * performance improvement.
  72          *
  73          * @param array $modules List of module names to preload information for
  74          * @param ResourceLoaderContext $context Context to load the information within
  75          */
  76         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  77                 if ( !count( $modules ) ) {
  78                         // Or else Database*::select() will explode, plus it's cheaper!
  79                         return;
  80                 }
  81                 $dbr = wfGetDB( DB_SLAVE );
  82                 $skin = $context->getSkin();
  83                 $lang = $context->getLanguage();
  84
  85                 // Get file dependency information
  86                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  87                                 'md_module' => $modules,
  88                                 'md_skin' => $skin
  89                         ), __METHOD__
  90                 );
  91
  92                 // Set modules' dependencies
  93                 $modulesWithDeps = array();
  94                 foreach ( $res as $row ) {
  95                         $module = $this->getModule( $row->md_module );
  96                         if ( $module ) {
  97                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
  98                                 $modulesWithDeps[] = $row->md_module;
  99                         }
 100                 }
 101
 102                 // Register the absence of a dependency row too
 103                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 104                         $module = $this->getModule( $name );
 105                         if ( $module ) {
 106                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 107                         }
 108                 }
 109
 110                 // Get message blob mtimes. Only do this for modules with messages
 111                 $modulesWithMessages = array();
 112                 foreach ( $modules as $name ) {
 113                         $module = $this->getModule( $name );
 114                         if ( $module && count( $module->getMessages() ) ) {
 115                                 $modulesWithMessages[] = $name;
 116                         }
 117                 }
 118                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 119                 if ( count( $modulesWithMessages ) ) {
 120                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 121                                         'mr_resource' => $modulesWithMessages,
 122                                         'mr_lang' => $lang
 123                                 ), __METHOD__
 124                         );
 125                         foreach ( $res as $row ) {
 126                                 $module = $this->getModule( $row->mr_resource );
 127                                 if ( $module ) {
 128                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 129                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 130                                 }
 131                         }
 132                 }
 133                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 134                         $module = $this->getModule( $name );
 135                         if ( $module ) {
 136                                 $module->setMsgBlobMtime( $lang, 0 );
 137                         }
 138                 }
 139         }
 140
 141         /**
 142          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 143          *
 144          * Available filters are:
 145          *
 146          *    - minify-js \see JavaScriptMinifier::minify
 147          *    - minify-css \see CSSMin::minify
 148          *
 149          * If $data is empty, only contains whitespace or the filter was unknown,
 150          * $data is returned unmodified.
 151          *
 152          * @param string $filter Name of filter to run
 153          * @param string $data Text to filter, such as JavaScript or CSS text
 154          * @param string $cacheReport Whether to include the cache key report
 155          * @return string Filtered data, or a comment containing an error message
 156          */
 157         public function filter( $filter, $data, $cacheReport = true ) {
 158                 wfProfileIn( __METHOD__ );
 159
 160                 // For empty/whitespace-only data or for unknown filters, don't perform
 161                 // any caching or processing
 162                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 163                         wfProfileOut( __METHOD__ );
 164                         return $data;
 165                 }
 166
 167                 // Try for cache hit
 168                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 169                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 170                 $cache = wfGetCache( CACHE_ANYTHING );
 171                 $cacheEntry = $cache->get( $key );
 172                 if ( is_string( $cacheEntry ) ) {
 173                         wfIncrStats( "rl-$filter-cache-hits" );
 174                         wfProfileOut( __METHOD__ );
 175                         return $cacheEntry;
 176                 }
 177
 178                 $result = '';
 179                 // Run the filter - we've already verified one of these will work
 180                 try {
 181                         wfIncrStats( "rl-$filter-cache-misses" );
 182                         switch ( $filter ) {
 183                                 case 'minify-js':
 184                                         $result = JavaScriptMinifier::minify( $data,
 185                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 186                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 187                                         );
 188                                         if ( $cacheReport ) {
 189                                                 $result .= "\n/* cache key: $key */";
 190                                         }
 191                                         break;
 192                                 case 'minify-css':
 193                                         $result = CSSMin::minify( $data );
 194                                         if ( $cacheReport ) {
 195                                                 $result .= "\n/* cache key: $key */";
 196                                         }
 197                                         break;
 198                         }
 199
 200                         // Save filtered text to Memcached
 201                         $cache->set( $key, $result );
 202                 } catch ( Exception $e ) {
 203                         MWExceptionHandler::logException( $e );
 204                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 205                         $this->hasErrors = true;
 206                         // Return exception as a comment
 207                         $result = self::formatException( $e );
 208                 }
 209
 210                 wfProfileOut( __METHOD__ );
 211
 212                 return $result;
 213         }
 214
 215         /* Methods */
 216
 217         /**
 218          * Register core modules and runs registration hooks.
 219          */
 220         public function __construct( Config $config = null ) {
 221                 global $IP;
 222
 223                 wfProfileIn( __METHOD__ );
 224
 225                 if ( $config === null ) {
 226                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 227                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 228                 }
 229
 230                 $this->config = $config;
 231
 232                 // Add 'local' source first
 233                 $this->addSource(
 234                         'local',
 235                         array( 'loadScript' => wfScript( 'load' ), 'apiScript' => wfScript( 'api' ) )
 236                 );
 237
 238                 // Add other sources
 239                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 240
 241                 // Register core modules
 242                 $this->register( include "$IP/resources/Resources.php" );
 243                 // Register extension modules
 244                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 245                 $this->register( $config->get( 'ResourceModules' ) );
 246
 247                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 248                         $this->registerTestModules();
 249                 }
 250
 251                 wfProfileOut( __METHOD__ );
 252         }
 253
 254         /**
 255          * @return Config
 256          */
 257         public function getConfig() {
 258                 return $this->config;
 259         }
 260
 261         /**
 262          * Register a module with the ResourceLoader system.
 263          *
 264          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 265          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 266          *   this may also be a ResourceLoaderModule object. Optional when using
 267          *   multiple-registration calling style.
 268          * @throws MWException If a duplicate module registration is attempted
 269          * @throws MWException If a module name contains illegal characters (pipes or commas)
 270          * @throws MWException If something other than a ResourceLoaderModule is being registered
 271          * @return bool False if there were any errors, in which case one or more modules were
 272          *   not registered
 273          */
 274         public function register( $name, $info = null ) {
 275                 wfProfileIn( __METHOD__ );
 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                                 wfProfileOut( __METHOD__ );
 283                                 // A module has already been registered by this name
 284                                 throw new MWException(
 285                                         'ResourceLoader duplicate registration error. ' .
 286                                         'Another module has already been registered as ' . $name
 287                                 );
 288                         }
 289
 290                         // Check $name for validity
 291                         if ( !self::isValidModuleName( $name ) ) {
 292                                 wfProfileOut( __METHOD__ );
 293                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 294                                         . "see ResourceLoader::isValidModuleName()" );
 295                         }
 296
 297                         // Attach module
 298                         if ( $info instanceof ResourceLoaderModule ) {
 299                                 $this->moduleInfos[$name] = array( 'object' => $info );
 300                                 $info->setName( $name );
 301                                 $this->modules[$name] = $info;
 302                         } elseif ( is_array( $info ) ) {
 303                                 // New calling convention
 304                                 $this->moduleInfos[$name] = $info;
 305                         } else {
 306                                 wfProfileOut( __METHOD__ );
 307                                 throw new MWException(
 308                                         'ResourceLoader module info type error for module \'' . $name .
 309                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 310                                 );
 311                         }
 312
 313                         // Last-minute changes
 314
 315                         // Apply custom skin-defined styles to existing modules.
 316                         if ( $this->isFileModule( $name ) ) {
 317                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 318                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 319                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 320                                                 continue;
 321                                         }
 322
 323                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 324                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 325                                         if ( isset( $skinStyles[$name] ) ) {
 326                                                 $paths = (array)$skinStyles[$name];
 327                                                 $styleFiles = array();
 328                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 329                                                 $paths = (array)$skinStyles['+' . $name];
 330                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 331                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 332                                                         array();
 333                                         } else {
 334                                                 continue;
 335                                         }
 336
 337                                         // Add new file paths, remapping them to refer to our directories and not use settings
 338                                         // from the module we're modifying. These can come from the base definition or be defined
 339                                         // for each module.
 340                                         list( $localBasePath, $remoteBasePath ) =
 341                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 342                                         list( $localBasePath, $remoteBasePath ) =
 343                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 344
 345                                         foreach ( $paths as $path ) {
 346                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 347                                         }
 348
 349                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 350                                 }
 351                         }
 352                 }
 353
 354                 wfProfileOut( __METHOD__ );
 355         }
 356
 357         /**
 358          */
 359         public function registerTestModules() {
 360                 global $IP;
 361
 362                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 363                         throw new MWException( 'Attempt to register JavaScript test modules '
 364                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 365                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 366                 }
 367
 368                 wfProfileIn( __METHOD__ );
 369
 370                 // Get core test suites
 371                 $testModules = array();
 372                 $testModules['qunit'] = array();
 373                 // Get other test suites (e.g. from extensions)
 374                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 375
 376                 // Add the testrunner (which configures QUnit) to the dependencies.
 377                 // Since it must be ready before any of the test suites are executed.
 378                 foreach ( $testModules['qunit'] as &$module ) {
 379                         // Make sure all test modules are top-loading so that when QUnit starts
 380                         // on document-ready, it will run once and finish. If some tests arrive
 381                         // later (possibly after QUnit has already finished) they will be ignored.
 382                         $module['position'] = 'top';
 383                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 384                 }
 385
 386                 $testModules['qunit'] =
 387                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 388
 389                 foreach ( $testModules as $id => $names ) {
 390                         // Register test modules
 391                         $this->register( $testModules[$id] );
 392
 393                         // Keep track of their names so that they can be loaded together
 394                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 395                 }
 396
 397                 wfProfileOut( __METHOD__ );
 398         }
 399
 400         /**
 401          * Add a foreign source of modules.
 402          *
 403          * Source properties:
 404          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 405          *
 406          * @param mixed $id Source ID (string), or array( id1 => props1, id2 => props2, ... )
 407          * @param array $properties Source properties
 408          * @throws MWException
 409          */
 410         public function addSource( $id, $properties = null ) {
 411                 // Allow multiple sources to be registered in one call
 412                 if ( is_array( $id ) ) {
 413                         foreach ( $id as $key => $value ) {
 414                                 $this->addSource( $key, $value );
 415                         }
 416                         return;
 417                 }
 418
 419                 // Disallow duplicates
 420                 if ( isset( $this->sources[$id] ) ) {
 421                         throw new MWException(
 422                                 'ResourceLoader duplicate source addition error. ' .
 423                                 'Another source has already been registered as ' . $id
 424                         );
 425                 }
 426
 427                 // Validate properties
 428                 foreach ( self::$requiredSourceProperties as $prop ) {
 429                         if ( !isset( $properties[$prop] ) ) {
 430                                 throw new MWException( "Required property $prop missing from source ID $id" );
 431                         }
 432                 }
 433
 434                 $this->sources[$id] = $properties;
 435         }
 436
 437         /**
 438          * Get a list of module names.
 439          *
 440          * @return array List of module names
 441          */
 442         public function getModuleNames() {
 443                 return array_keys( $this->moduleInfos );
 444         }
 445
 446         /**
 447          * Get a list of test module names for one (or all) frameworks.
 448          *
 449          * If the given framework id is unknkown, or if the in-object variable is not an array,
 450          * then it will return an empty array.
 451          *
 452          * @param string $framework Get only the test module names for one
 453          *   particular framework (optional)
 454          * @return array
 455          */
 456         public function getTestModuleNames( $framework = 'all' ) {
 457                 /** @todo api siteinfo prop testmodulenames modulenames */
 458                 if ( $framework == 'all' ) {
 459                         return $this->testModuleNames;
 460                 } elseif ( isset( $this->testModuleNames[$framework] )
 461                         && is_array( $this->testModuleNames[$framework] )
 462                 ) {
 463                         return $this->testModuleNames[$framework];
 464                 } else {
 465                         return array();
 466                 }
 467         }
 468
 469         /**
 470          * Get the ResourceLoaderModule object for a given module name.
 471          *
 472          * If an array of module parameters exists but a ResourceLoaderModule object has not
 473          * yet been instantiated, this method will instantiate and cache that object such that
 474          * subsequent calls simply return the same object.
 475          *
 476          * @param string $name Module name
 477          * @return ResourceLoaderModule|null If module has been registered, return a
 478          *  ResourceLoaderModule instance. Otherwise, return null.
 479          */
 480         public function getModule( $name ) {
 481                 if ( !isset( $this->modules[$name] ) ) {
 482                         if ( !isset( $this->moduleInfos[$name] ) ) {
 483                                 // No such module
 484                                 return null;
 485                         }
 486                         // Construct the requested object
 487                         $info = $this->moduleInfos[$name];
 488                         /** @var ResourceLoaderModule $object */
 489                         if ( isset( $info['object'] ) ) {
 490                                 // Object given in info array
 491                                 $object = $info['object'];
 492                         } else {
 493                                 if ( !isset( $info['class'] ) ) {
 494                                         $class = 'ResourceLoaderFileModule';
 495                                 } else {
 496                                         $class = $info['class'];
 497                                 }
 498                                 /** @var ResourceLoaderModule $object */
 499                                 $object = new $class( $info );
 500                                 $object->setConfig( $this->getConfig() );
 501                         }
 502                         $object->setName( $name );
 503                         $this->modules[$name] = $object;
 504                 }
 505
 506                 return $this->modules[$name];
 507         }
 508
 509         /**
 510          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 511          *
 512          * @param string $name Module name
 513          * @return bool
 514          */
 515         protected function isFileModule( $name ) {
 516                 if ( !isset( $this->moduleInfos[$name] ) ) {
 517                         return false;
 518                 }
 519                 $info = $this->moduleInfos[$name];
 520                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 521                         return false;
 522                 }
 523                 return true;
 524         }
 525
 526         /**
 527          * Get the list of sources.
 528          *
 529          * @return array Like array( id => array of properties, .. )
 530          */
 531         public function getSources() {
 532                 return $this->sources;
 533         }
 534
 535         /**
 536          * Get the URL to the load.php endpoint for the given
 537          * ResourceLoader source
 538          *
 539          * @since 1.24
 540          * @param string $source
 541          * @throws MWException On an invalid $source name
 542          * @return string
 543          */
 544         public function getLoadScript( $source ) {
 545                 if ( !isset( $this->sources[$source] ) ) {
 546                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 547                 }
 548                 return $this->sources[$source]['loadScript'];
 549         }
 550
 551         /**
 552          * Output a response to a load request, including the content-type header.
 553          *
 554          * @param ResourceLoaderContext $context Context in which a response should be formed
 555          */
 556         public function respond( ResourceLoaderContext $context ) {
 557                 // Use file cache if enabled and available...
 558                 if ( $this->config->get( 'UseFileCache' ) ) {
 559                         $fileCache = ResourceFileCache::newFromContext( $context );
 560                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 561                                 return; // output handled
 562                         }
 563                 }
 564
 565                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 566                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 567                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 568                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 569                 // the whole thing in our own output buffer to be sure the active buffer
 570                 // doesn't use ob_gzhandler.
 571                 // See http://bugs.php.net/bug.php?id=36514
 572                 ob_start();
 573
 574                 wfProfileIn( __METHOD__ );
 575                 $errors = '';
 576
 577                 // Find out which modules are missing and instantiate the others
 578                 $modules = array();
 579                 $missing = array();
 580                 foreach ( $context->getModules() as $name ) {
 581                         $module = $this->getModule( $name );
 582                         if ( $module ) {
 583                                 // Do not allow private modules to be loaded from the web.
 584                                 // This is a security issue, see bug 34907.
 585                                 if ( $module->getGroup() === 'private' ) {
 586                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 587                                         $this->hasErrors = true;
 588                                         // Add exception to the output as a comment
 589                                         $errors .= self::makeComment( "Cannot show private module \"$name\"" );
 590
 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->hasErrors = true;
 606                         // Add exception to the output as a comment
 607                         $errors .= self::formatException( $e );
 608                 }
 609
 610                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 611
 612                 // To send Last-Modified and support If-Modified-Since, we need to detect
 613                 // the last modified time
 614                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 615                 foreach ( $modules as $module ) {
 616                         /**
 617                          * @var $module ResourceLoaderModule
 618                          */
 619                         try {
 620                                 // Calculate maximum modified time
 621                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 622                         } catch ( Exception $e ) {
 623                                 MWExceptionHandler::logException( $e );
 624                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 625                                 $this->hasErrors = true;
 626                                 // Add exception to the output as a comment
 627                                 $errors .= self::formatException( $e );
 628                         }
 629                 }
 630
 631                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 632
 633                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 634                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 635                         wfProfileOut( __METHOD__ );
 636                         return; // output handled (buffers cleared)
 637                 }
 638
 639                 // Generate a response
 640                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 641
 642                 // Prepend comments indicating exceptions
 643                 $response = $errors . $response;
 644
 645                 // Capture any PHP warnings from the output buffer and append them to the
 646                 // response in a comment if we're in debug mode.
 647                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 648                         $response = self::makeComment( $warnings ) . $response;
 649                         $this->hasErrors = true;
 650                 }
 651
 652                 // Save response to file cache unless there are errors
 653                 if ( isset( $fileCache ) && !$errors && !count( $missing ) ) {
 654                         // Cache single modules...and other requests if there are enough hits
 655                         if ( ResourceFileCache::useFileCache( $context ) ) {
 656                                 if ( $fileCache->isCacheWorthy() ) {
 657                                         $fileCache->saveText( $response );
 658                                 } else {
 659                                         $fileCache->incrMissesRecent( $context->getRequest() );
 660                                 }
 661                         }
 662                 }
 663
 664                 // Send content type and cache related headers
 665                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 666
 667                 // Remove the output buffer and output the response
 668                 ob_end_clean();
 669                 echo $response;
 670
 671                 wfProfileOut( __METHOD__ );
 672         }
 673
 674         /**
 675          * Send content type and last modified headers to the client.
 676          * @param ResourceLoaderContext $context
 677          * @param string $mtime TS_MW timestamp to use for last-modified
 678          * @param bool $errors Whether there are commented-out errors in the response
 679          * @return void
 680          */
 681         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 682                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 683                 // If a version wasn't specified we need a shorter expiry time for updates
 684                 // to propagate to clients quickly
 685                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 686                 if ( is_null( $context->getVersion() ) || $errors ) {
 687                         $maxage = $rlMaxage['unversioned']['client'];
 688                         $smaxage = $rlMaxage['unversioned']['server'];
 689                 // If a version was specified we can use a longer expiry time since changing
 690                 // version numbers causes cache misses
 691                 } else {
 692                         $maxage = $rlMaxage['versioned']['client'];
 693                         $smaxage = $rlMaxage['versioned']['server'];
 694                 }
 695                 if ( $context->getOnly() === 'styles' ) {
 696                         header( 'Content-Type: text/css; charset=utf-8' );
 697                         header( 'Access-Control-Allow-Origin: *' );
 698                 } else {
 699                         header( 'Content-Type: text/javascript; charset=utf-8' );
 700                 }
 701                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 702                 if ( $context->getDebug() ) {
 703                         // Do not cache debug responses
 704                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 705                         header( 'Pragma: no-cache' );
 706                 } else {
 707                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 708                         $exp = min( $maxage, $smaxage );
 709                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 710                 }
 711         }
 712
 713         /**
 714          * Respond with 304 Last Modified if appropiate.
 715          *
 716          * If there's an If-Modified-Since header, respond with a 304 appropriately
 717          * and clear out the output buffer. If the client cache is too old then do nothing.
 718          *
 719          * @param ResourceLoaderContext $context
 720          * @param string $mtime The TS_MW timestamp to check the header against
 721          * @return bool True if 304 header sent and output handled
 722          */
 723         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 724                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 725                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 726                 // so we get a valid timestamp.
 727                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 728                 // Never send 304s in debug mode
 729                 if ( $ims !== false && !$context->getDebug() ) {
 730                         $imsTS = strtok( $ims, ';' );
 731                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 732                                 // There's another bug in ob_gzhandler (see also the comment at
 733                                 // the top of this function) that causes it to gzip even empty
 734                                 // responses, meaning it's impossible to produce a truly empty
 735                                 // response (because the gzip header is always there). This is
 736                                 // a problem because 304 responses have to be completely empty
 737                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 738                                 // See also http://bugs.php.net/bug.php?id=51579
 739                                 // To work around this, we tear down all output buffering before
 740                                 // sending the 304.
 741                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 742
 743                                 header( 'HTTP/1.0 304 Not Modified' );
 744                                 header( 'Status: 304 Not Modified' );
 745                                 return true;
 746                         }
 747                 }
 748                 return false;
 749         }
 750
 751         /**
 752          * Send out code for a response from file cache if possible.
 753          *
 754          * @param ResourceFileCache $fileCache Cache object for this request URL
 755          * @param ResourceLoaderContext $context Context in which to generate a response
 756          * @return bool If this found a cache file and handled the response
 757          */
 758         protected function tryRespondFromFileCache(
 759                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 760         ) {
 761                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 762                 // Buffer output to catch warnings.
 763                 ob_start();
 764                 // Get the maximum age the cache can be
 765                 $maxage = is_null( $context->getVersion() )
 766                         ? $rlMaxage['unversioned']['server']
 767                         : $rlMaxage['versioned']['server'];
 768                 // Minimum timestamp the cache file must have
 769                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 770                 if ( !$good ) {
 771                         try { // RL always hits the DB on file cache miss...
 772                                 wfGetDB( DB_SLAVE );
 773                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 774                                 $good = $fileCache->isCacheGood(); // cache existence check
 775                         }
 776                 }
 777                 if ( $good ) {
 778                         $ts = $fileCache->cacheTimestamp();
 779                         // Send content type and cache headers
 780                         $this->sendResponseHeaders( $context, $ts, false );
 781                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 782                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 783                                 return false; // output handled (buffers cleared)
 784                         }
 785                         $response = $fileCache->fetchText();
 786                         // Capture any PHP warnings from the output buffer and append them to the
 787                         // response in a comment if we're in debug mode.
 788                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 789                                 $response = "/*\n$warnings\n*/\n" . $response;
 790                         }
 791                         // Remove the output buffer and output the response
 792                         ob_end_clean();
 793                         echo $response . "\n/* Cached {$ts} */";
 794                         return true; // cache hit
 795                 }
 796                 // Clear buffer
 797                 ob_end_clean();
 798
 799                 return false; // cache miss
 800         }
 801
 802         /**
 803          * Generate a CSS or JS comment block.
 804          *
 805          * Only use this for public data, not error message details.
 806          *
 807          * @param string $text
 808          * @return string
 809          */
 810         public static function makeComment( $text ) {
 811                 $encText = str_replace( '*/', '* /', $text );
 812                 return "/*\n$encText\n*/\n";
 813         }
 814
 815         /**
 816          * Handle exception display.
 817          *
 818          * @param Exception $e Exception to be shown to the user
 819          * @return string Sanitized text that can be returned to the user
 820          */
 821         public static function formatException( $e ) {
 822                 global $wgShowExceptionDetails;
 823
 824                 if ( $wgShowExceptionDetails ) {
 825                         return self::makeComment( $e->__toString() );
 826                 } else {
 827                         return self::makeComment( wfMessage( 'internalerror' )->text() );
 828                 }
 829         }
 830
 831         /**
 832          * Generate code for a response.
 833          *
 834          * @param ResourceLoaderContext $context Context in which to generate a response
 835          * @param array $modules List of module objects keyed by module name
 836          * @param array $missing List of requested module names that are unregistered (optional)
 837          * @return string Response data
 838          */
 839         public function makeModuleResponse( ResourceLoaderContext $context,
 840                 array $modules, array $missing = array()
 841         ) {
 842                 $out = '';
 843                 $exceptions = '';
 844                 $states = array();
 845
 846                 if ( !count( $modules ) && !count( $missing ) ) {
 847                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 848    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 849    no modules were requested. Max made me put this here. */";
 850                 }
 851
 852                 wfProfileIn( __METHOD__ );
 853
 854                 // Pre-fetch blobs
 855                 if ( $context->shouldIncludeMessages() ) {
 856                         try {
 857                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 858                         } catch ( Exception $e ) {
 859                                 MWExceptionHandler::logException( $e );
 860                                 wfDebugLog(
 861                                         'resourceloader',
 862                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 863                                 );
 864                                 $this->hasErrors = true;
 865                                 // Add exception to the output as a comment
 866                                 $exceptions .= self::formatException( $e );
 867                         }
 868                 } else {
 869                         $blobs = array();
 870                 }
 871
 872                 foreach ( $missing as $name ) {
 873                         $states[$name] = 'missing';
 874                 }
 875
 876                 // Generate output
 877                 $isRaw = false;
 878                 foreach ( $modules as $name => $module ) {
 879                         /**
 880                          * @var $module ResourceLoaderModule
 881                          */
 882
 883                         wfProfileIn( __METHOD__ . '-' . $name );
 884                         try {
 885                                 $scripts = '';
 886                                 if ( $context->shouldIncludeScripts() ) {
 887                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 888                                         // However, we can't do this if the module doesn't support it
 889                                         // We also can't do this if there is an only= parameter, because we have to give
 890                                         // the module a way to return a load.php URL without causing an infinite loop
 891                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 892                                                 $scripts = $module->getScriptURLsForDebug( $context );
 893                                         } else {
 894                                                 $scripts = $module->getScript( $context );
 895                                                 // rtrim() because there are usually a few line breaks
 896                                                 // after the last ';'. A new line at EOF, a new line
 897                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 898                                                 if ( is_string( $scripts )
 899                                                         && strlen( $scripts )
 900                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 901                                                 ) {
 902                                                         // Append semicolon to prevent weird bugs caused by files not
 903                                                         // terminating their statements right (bug 27054)
 904                                                         $scripts .= ";\n";
 905                                                 }
 906                                         }
 907                                 }
 908                                 // Styles
 909                                 $styles = array();
 910                                 if ( $context->shouldIncludeStyles() ) {
 911                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 912                                         // that don't *have* any stylesheets (bug 38024).
 913                                         $stylePairs = $module->getStyles( $context );
 914                                         if ( count( $stylePairs ) ) {
 915                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 916                                                 // See comment near shouldIncludeScripts() for more details
 917                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 918                                                         $styles = array(
 919                                                                 'url' => $module->getStyleURLsForDebug( $context )
 920                                                         );
 921                                                 } else {
 922                                                         // Minify CSS before embedding in mw.loader.implement call
 923                                                         // (unless in debug mode)
 924                                                         if ( !$context->getDebug() ) {
 925                                                                 foreach ( $stylePairs as $media => $style ) {
 926                                                                         // Can be either a string or an array of strings.
 927                                                                         if ( is_array( $style ) ) {
 928                                                                                 $stylePairs[$media] = array();
 929                                                                                 foreach ( $style as $cssText ) {
 930                                                                                         if ( is_string( $cssText ) ) {
 931                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 932                                                                                         }
 933                                                                                 }
 934                                                                         } elseif ( is_string( $style ) ) {
 935                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 936                                                                         }
 937                                                                 }
 938                                                         }
 939                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 940                                                         $styles = array(
 941                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 942                                                         );
 943                                                 }
 944                                         }
 945                                 }
 946
 947                                 // Messages
 948                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 949
 950                                 // Append output
 951                                 switch ( $context->getOnly() ) {
 952                                         case 'scripts':
 953                                                 if ( is_string( $scripts ) ) {
 954                                                         // Load scripts raw...
 955                                                         $out .= $scripts;
 956                                                 } elseif ( is_array( $scripts ) ) {
 957                                                         // ...except when $scripts is an array of URLs
 958                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 959                                                 }
 960                                                 break;
 961                                         case 'styles':
 962                                                 // We no longer seperate into media, they are all combined now with
 963                                                 // custom media type groups into @media .. {} sections as part of the css string.
 964                                                 // Module returns either an empty array or a numerical array with css strings.
 965                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 966                                                 break;
 967                                         case 'messages':
 968                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 969                                                 break;
 970                                         default:
 971                                                 $out .= self::makeLoaderImplementScript(
 972                                                         $name,
 973                                                         $scripts,
 974                                                         $styles,
 975                                                         new XmlJsCode( $messagesBlob )
 976                                                 );
 977                                                 break;
 978                                 }
 979                         } catch ( Exception $e ) {
 980                                 MWExceptionHandler::logException( $e );
 981                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
 982                                 $this->hasErrors = true;
 983                                 // Add exception to the output as a comment
 984                                 $exceptions .= self::formatException( $e );
 985
 986                                 // Respond to client with error-state instead of module implementation
 987                                 $states[$name] = 'error';
 988                                 unset( $modules[$name] );
 989                         }
 990                         $isRaw |= $module->isRaw();
 991                         wfProfileOut( __METHOD__ . '-' . $name );
 992                 }
 993
 994                 // Update module states
 995                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
 996                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
 997                                 // Set the state of modules loaded as only scripts to ready as
 998                                 // they don't have an mw.loader.implement wrapper that sets the state
 999                                 foreach ( $modules as $name => $module ) {
1000                                         $states[$name] = 'ready';
1001                                 }
1002                         }
1003
1004                         // Set the state of modules we didn't respond to with mw.loader.implement
1005                         if ( count( $states ) ) {
1006                                 $out .= self::makeLoaderStateScript( $states );
1007                         }
1008
1009                         // In only=script requests for modules that are not raw (e.g. not the startup module)
1010                         // ensure the execution is conditional to avoid situations where browsers with an
1011                         // unsupported environment do unconditionally execute a module's scripts. Otherwise users
1012                         // will get things like "ReferenceError: mw is undefined" or "jQuery is undefined" from
1013                         // legacy scripts loaded with only=scripts (such as the 'site' module).
1014                         $out = self::makeLoaderConditionalScript( $out );
1015                 } else {
1016                         if ( count( $states ) ) {
1017                                 $exceptions .= self::makeComment(
1018                                         'Problematic modules: ' . FormatJson::encode( $states, ResourceLoader::inDebugMode() )
1019                                 );
1020                         }
1021                 }
1022
1023                 if ( !$context->getDebug() ) {
1024                         if ( $context->getOnly() === 'styles' ) {
1025                                 $out = $this->filter( 'minify-css', $out );
1026                         } else {
1027                                 $out = $this->filter( 'minify-js', $out );
1028                         }
1029                 }
1030
1031                 wfProfileOut( __METHOD__ );
1032                 return $exceptions . $out;
1033         }
1034
1035         /* Static Methods */
1036
1037         /**
1038          * Return JS code that calls mw.loader.implement with given module properties.
1039          *
1040          * @param string $name Module name
1041          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1042          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1043          *   to CSS files keyed by media type
1044          * @param mixed $messages List of messages associated with this module. May either be an
1045          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1046          *   the same data, wrapped in an XmlJsCode object.
1047          * @throws MWException
1048          * @return string
1049          */
1050         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
1051                 if ( is_string( $scripts ) ) {
1052                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1053                 } elseif ( !is_array( $scripts ) ) {
1054                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1055                 }
1056                 return Xml::encodeJsCall(
1057                         'mw.loader.implement',
1058                         array(
1059                                 $name,
1060                                 $scripts,
1061                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1062                                 // Although these variables are associative arrays, which become javascript
1063                                 // objects through json_encode. In many cases they will be empty arrays, and
1064                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1065                                 // output javascript "[]" instead of "{}". This fixes that.
1066                                 (object)$styles,
1067                                 (object)$messages
1068                         ),
1069                         ResourceLoader::inDebugMode()
1070                 );
1071         }
1072
1073         /**
1074          * Returns JS code which, when called, will register a given list of messages.
1075          *
1076          * @param mixed $messages Either an associative array mapping message key to value, or a
1077          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1078          * @return string
1079          */
1080         public static function makeMessageSetScript( $messages ) {
1081                 return Xml::encodeJsCall(
1082                         'mw.messages.set',
1083                         array( (object)$messages ),
1084                         ResourceLoader::inDebugMode()
1085                 );
1086         }
1087
1088         /**
1089          * Combines an associative array mapping media type to CSS into a
1090          * single stylesheet with "@media" blocks.
1091          *
1092          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1093          * @return array
1094          */
1095         public static function makeCombinedStyles( array $stylePairs ) {
1096                 $out = array();
1097                 foreach ( $stylePairs as $media => $styles ) {
1098                         // ResourceLoaderFileModule::getStyle can return the styles
1099                         // as a string or an array of strings. This is to allow separation in
1100                         // the front-end.
1101                         $styles = (array)$styles;
1102                         foreach ( $styles as $style ) {
1103                                 $style = trim( $style );
1104                                 // Don't output an empty "@media print { }" block (bug 40498)
1105                                 if ( $style !== '' ) {
1106                                         // Transform the media type based on request params and config
1107                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1108                                         $media = OutputPage::transformCssMedia( $media );
1109
1110                                         if ( $media === '' || $media == 'all' ) {
1111                                                 $out[] = $style;
1112                                         } elseif ( is_string( $media ) ) {
1113                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1114                                         }
1115                                         // else: skip
1116                                 }
1117                         }
1118                 }
1119                 return $out;
1120         }
1121
1122         /**
1123          * Returns a JS call to mw.loader.state, which sets the state of a
1124          * module or modules to a given value. Has two calling conventions:
1125          *
1126          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1127          *         Set the state of a single module called $name to $state
1128          *
1129          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1130          *         Set the state of modules with the given names to the given states
1131          *
1132          * @param string $name
1133          * @param string $state
1134          * @return string
1135          */
1136         public static function makeLoaderStateScript( $name, $state = null ) {
1137                 if ( is_array( $name ) ) {
1138                         return Xml::encodeJsCall(
1139                                 'mw.loader.state',
1140                                 array( $name ),
1141                                 ResourceLoader::inDebugMode()
1142                         );
1143                 } else {
1144                         return Xml::encodeJsCall(
1145                                 'mw.loader.state',
1146                                 array( $name, $state ),
1147                                 ResourceLoader::inDebugMode()
1148                         );
1149                 }
1150         }
1151
1152         /**
1153          * Returns JS code which calls the script given by $script. The script will
1154          * be called with local variables name, version, dependencies and group,
1155          * which will have values corresponding to $name, $version, $dependencies
1156          * and $group as supplied.
1157          *
1158          * @param string $name Module name
1159          * @param int $version Module version number as a timestamp
1160          * @param array $dependencies List of module names on which this module depends
1161          * @param string $group Group which the module is in.
1162          * @param string $source Source of the module, or 'local' if not foreign.
1163          * @param string $script JavaScript code
1164          * @return string
1165          */
1166         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1167                 $group, $source, $script
1168         ) {
1169                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1170                 return Xml::encodeJsCall(
1171                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1172                         array( $name, $version, $dependencies, $group, $source ),
1173                         ResourceLoader::inDebugMode()
1174                 );
1175         }
1176
1177         /**
1178          * Returns JS code which calls mw.loader.register with the given
1179          * parameters. Has three calling conventions:
1180          *
1181          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source, $skip ):
1182          *       Register a single module.
1183          *
1184          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1185          *       Register modules with the given names.
1186          *
1187          *   - ResourceLoader::makeLoaderRegisterScript( array(
1188          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1189          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1190          *        ...
1191          *     ) ):
1192          *        Registers modules with the given names and parameters.
1193          *
1194          * @param string $name Module name
1195          * @param int $version Module version number as a timestamp
1196          * @param array $dependencies List of module names on which this module depends
1197          * @param string $group Group which the module is in
1198          * @param string $source Source of the module, or 'local' if not foreign
1199          * @param string $skip Script body of the skip function
1200          * @return string
1201          */
1202         public static function makeLoaderRegisterScript( $name, $version = null,
1203                 $dependencies = null, $group = null, $source = null, $skip = null
1204         ) {
1205                 if ( is_array( $name ) ) {
1206                         return Xml::encodeJsCall(
1207                                 'mw.loader.register',
1208                                 array( $name ),
1209                                 ResourceLoader::inDebugMode()
1210                         );
1211                 } else {
1212                         $version = (int)$version > 1 ? (int)$version : 1;
1213                         return Xml::encodeJsCall(
1214                                 'mw.loader.register',
1215                                 array( $name, $version, $dependencies, $group, $source, $skip ),
1216                                 ResourceLoader::inDebugMode()
1217                         );
1218                 }
1219         }
1220
1221         /**
1222          * Returns JS code which calls mw.loader.addSource() with the given
1223          * parameters. Has two calling conventions:
1224          *
1225          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1226          *       Register a single source
1227          *
1228          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
1229          *       Register sources with the given IDs and properties.
1230          *
1231          * @param string $id Source ID
1232          * @param array $properties Source properties (see addSource())
1233          * @return string
1234          */
1235         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1236                 if ( is_array( $id ) ) {
1237                         return Xml::encodeJsCall(
1238                                 'mw.loader.addSource',
1239                                 array( $id ),
1240                                 ResourceLoader::inDebugMode()
1241                         );
1242                 } else {
1243                         return Xml::encodeJsCall(
1244                                 'mw.loader.addSource',
1245                                 array( $id, $properties ),
1246                                 ResourceLoader::inDebugMode()
1247                         );
1248                 }
1249         }
1250
1251         /**
1252          * Returns JS code which runs given JS code if the client-side framework is
1253          * present.
1254          *
1255          * @param string $script JavaScript code
1256          * @return string
1257          */
1258         public static function makeLoaderConditionalScript( $script ) {
1259                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1260         }
1261
1262         /**
1263          * Returns JS code which will set the MediaWiki configuration array to
1264          * the given value.
1265          *
1266          * @param array $configuration List of configuration values keyed by variable name
1267          * @return string
1268          */
1269         public static function makeConfigSetScript( array $configuration ) {
1270                 return Xml::encodeJsCall(
1271                         'mw.config.set',
1272                         array( $configuration ),
1273                         ResourceLoader::inDebugMode()
1274                 );
1275         }
1276
1277         /**
1278          * Convert an array of module names to a packed query string.
1279          *
1280          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1281          * becomes 'foo.bar,baz|bar.baz,quux'
1282          * @param array $modules List of module names (strings)
1283          * @return string Packed query string
1284          */
1285         public static function makePackedModulesString( $modules ) {
1286                 $groups = array(); // array( prefix => array( suffixes ) )
1287                 foreach ( $modules as $module ) {
1288                         $pos = strrpos( $module, '.' );
1289                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1290                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1291                         $groups[$prefix][] = $suffix;
1292                 }
1293
1294                 $arr = array();
1295                 foreach ( $groups as $prefix => $suffixes ) {
1296                         $p = $prefix === '' ? '' : $prefix . '.';
1297                         $arr[] = $p . implode( ',', $suffixes );
1298                 }
1299                 $str = implode( '|', $arr );
1300                 return $str;
1301         }
1302
1303         /**
1304          * Determine whether debug mode was requested
1305          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1306          * @return bool
1307          */
1308         public static function inDebugMode() {
1309                 if ( self::$debugMode === null ) {
1310                         global $wgRequest, $wgResourceLoaderDebug;
1311                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1312                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1313                         );
1314                 }
1315                 return self::$debugMode;
1316         }
1317
1318         /**
1319          * Reset static members used for caching.
1320          *
1321          * Global state and $wgRequest are evil, but we're using it right
1322          * now and sometimes we need to be able to force ResourceLoader to
1323          * re-evaluate the context because it has changed (e.g. in the test suite).
1324          */
1325         public static function clearCache() {
1326                 self::$debugMode = null;
1327         }
1328
1329         /**
1330          * Build a load.php URL
1331          *
1332          * @since 1.24
1333          * @param string $source Name of the ResourceLoader source
1334          * @param ResourceLoaderContext $context
1335          * @param array $extraQuery
1336          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1337          */
1338         public function createLoaderURL( $source, ResourceLoaderContext $context,
1339                 $extraQuery = array()
1340         ) {
1341                 $query = self::createLoaderQuery( $context, $extraQuery );
1342                 $script = $this->getLoadScript( $source );
1343
1344                 // Prevent the IE6 extension check from being triggered (bug 28840)
1345                 // by appending a character that's invalid in Windows extensions ('*')
1346                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1347         }
1348
1349         /**
1350          * Build a load.php URL
1351          * @deprecated since 1.24, use createLoaderURL instead
1352          * @param array $modules Array of module names (strings)
1353          * @param string $lang Language code
1354          * @param string $skin Skin name
1355          * @param string|null $user User name. If null, the &user= parameter is omitted
1356          * @param string|null $version Versioning timestamp
1357          * @param bool $debug Whether the request should be in debug mode
1358          * @param string|null $only &only= parameter
1359          * @param bool $printable Printable mode
1360          * @param bool $handheld Handheld mode
1361          * @param array $extraQuery Extra query parameters to add
1362          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1363          */
1364         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1365                 $version = null, $debug = false, $only = null, $printable = false,
1366                 $handheld = false, $extraQuery = array()
1367         ) {
1368                 global $wgLoadScript;
1369
1370                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1371                         $only, $printable, $handheld, $extraQuery
1372                 );
1373
1374                 // Prevent the IE6 extension check from being triggered (bug 28840)
1375                 // by appending a character that's invalid in Windows extensions ('*')
1376                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1377         }
1378
1379         /**
1380          * Helper for createLoaderURL()
1381          *
1382          * @since 1.24
1383          * @see makeLoaderQuery
1384          * @param ResourceLoaderContext $context
1385          * @param array $extraQuery
1386          * @return array
1387          */
1388         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1389                 return self::makeLoaderQuery(
1390                         $context->getModules(),
1391                         $context->getLanguage(),
1392                         $context->getSkin(),
1393                         $context->getUser(),
1394                         $context->getVersion(),
1395                         $context->getDebug(),
1396                         $context->getOnly(),
1397                         $context->getRequest()->getBool( 'printable' ),
1398                         $context->getRequest()->getBool( 'handheld' ),
1399                         $extraQuery
1400                 );
1401         }
1402
1403         /**
1404          * Build a query array (array representation of query string) for load.php. Helper
1405          * function for makeLoaderURL().
1406          *
1407          * @param array $modules
1408          * @param string $lang
1409          * @param string $skin
1410          * @param string $user
1411          * @param string $version
1412          * @param bool $debug
1413          * @param string $only
1414          * @param bool $printable
1415          * @param bool $handheld
1416          * @param array $extraQuery
1417          *
1418          * @return array
1419          */
1420         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1421                 $version = null, $debug = false, $only = null, $printable = false,
1422                 $handheld = false, $extraQuery = array()
1423         ) {
1424                 $query = array(
1425                         'modules' => self::makePackedModulesString( $modules ),
1426                         'lang' => $lang,
1427                         'skin' => $skin,
1428                         'debug' => $debug ? 'true' : 'false',
1429                 );
1430                 if ( $user !== null ) {
1431                         $query['user'] = $user;
1432                 }
1433                 if ( $version !== null ) {
1434                         $query['version'] = $version;
1435                 }
1436                 if ( $only !== null ) {
1437                         $query['only'] = $only;
1438                 }
1439                 if ( $printable ) {
1440                         $query['printable'] = 1;
1441                 }
1442                 if ( $handheld ) {
1443                         $query['handheld'] = 1;
1444                 }
1445                 $query += $extraQuery;
1446
1447                 // Make queries uniform in order
1448                 ksort( $query );
1449                 return $query;
1450         }
1451
1452         /**
1453          * Check a module name for validity.
1454          *
1455          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1456          * at most 255 bytes.
1457          *
1458          * @param string $moduleName Module name to check
1459          * @return bool Whether $moduleName is a valid module name
1460          */
1461         public static function isValidModuleName( $moduleName ) {
1462                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1463         }
1464
1465         /**
1466          * Returns LESS compiler set up for use with MediaWiki
1467          *
1468          * @param Config $config
1469          * @throws MWException
1470          * @since 1.22
1471          * @return lessc
1472          */
1473         public static function getLessCompiler( Config $config ) {
1474                 // When called from the installer, it is possible that a required PHP extension
1475                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1476                 // exception (caught by the installer) to prevent a fatal error later on.
1477                 if ( !function_exists( 'ctype_digit' ) ) {
1478                         throw new MWException( 'lessc requires the Ctype extension' );
1479                 }
1480
1481                 $less = new lessc();
1482                 $less->setPreserveComments( true );
1483                 $less->setVariables( self::getLESSVars( $config ) );
1484                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1485                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1486                         $less->registerFunction( $name, $func );
1487                 }
1488                 return $less;
1489         }
1490
1491         /**
1492          * Get global LESS variables.
1493          *
1494          * @param Config $config
1495          * @since 1.22
1496          * @return array Map of variable names to string CSS values.
1497          */
1498         public static function getLESSVars( Config $config ) {
1499                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1500                 // Sort by key to ensure consistent hashing for cache lookups.
1501                 ksort( $lessVars );
1502                 return $lessVars;
1503         }
1504 }