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 use Psr\Log\LoggerAwareInterface;
  26 use Psr\Log\LoggerInterface;
  27 use Psr\Log\NullLogger;
  28 use WrappedString\WrappedString;
  29
  30 /**
  31  * Dynamic JavaScript and CSS resource loading system.
  32  *
  33  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  34  *    https://www.mediawiki.org/wiki/ResourceLoader
  35  */
  36 class ResourceLoader implements LoggerAwareInterface {
  37         /** @var int */
  38         protected static $filterCacheVersion = 7;
  39
  40         /** @var bool */
  41         protected static $debugMode = null;
  42
  43         /** @var array */
  44         private $lessVars = null;
  45
  46         /**
  47          * Module name/ResourceLoaderModule object pairs
  48          * @var array
  49          */
  50         protected $modules = [];
  51
  52         /**
  53          * Associative array mapping module name to info associative array
  54          * @var array
  55          */
  56         protected $moduleInfos = [];
  57
  58         /** @var Config $config */
  59         private $config;
  60
  61         /**
  62          * Associative array mapping framework ids to a list of names of test suite modules
  63          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  64          * @var array
  65          */
  66         protected $testModuleNames = [];
  67
  68         /**
  69          * E.g. array( 'source-id' => 'http://.../load.php' )
  70          * @var array
  71          */
  72         protected $sources = [];
  73
  74         /**
  75          * Errors accumulated during current respond() call.
  76          * @var array
  77          */
  78         protected $errors = [];
  79
  80         /**
  81          * @var MessageBlobStore
  82          */
  83         protected $blobStore;
  84
  85         /**
  86          * @var LoggerInterface
  87          */
  88         private $logger;
  89
  90         /** @var string JavaScript / CSS pragma to disable minification. **/
  91         const FILTER_NOMIN = '/*@nomin*/';
  92
  93         /**
  94          * Load information stored in the database about modules.
  95          *
  96          * This method grabs modules dependencies from the database and updates modules
  97          * objects.
  98          *
  99          * This is not inside the module code because it is much faster to
 100          * request all of the information at once than it is to have each module
 101          * requests its own information. This sacrifice of modularity yields a substantial
 102          * performance improvement.
 103          *
 104          * @param array $moduleNames List of module names to preload information for
 105          * @param ResourceLoaderContext $context Context to load the information within
 106          */
 107         public function preloadModuleInfo( array $moduleNames, ResourceLoaderContext $context ) {
 108                 if ( !$moduleNames ) {
 109                         // Or else Database*::select() will explode, plus it's cheaper!
 110                         return;
 111                 }
 112                 $dbr = wfGetDB( DB_SLAVE );
 113                 $skin = $context->getSkin();
 114                 $lang = $context->getLanguage();
 115
 116                 // Batched version of ResourceLoaderModule::getFileDependencies
 117                 $vary = "$skin|$lang";
 118                 $res = $dbr->select( 'module_deps', [ 'md_module', 'md_deps' ], [
 119                                 'md_module' => $moduleNames,
 120                                 'md_skin' => $vary,
 121                         ], __METHOD__
 122                 );
 123
 124                 // Prime in-object cache for file dependencies
 125                 $modulesWithDeps = [];
 126                 foreach ( $res as $row ) {
 127                         $module = $this->getModule( $row->md_module );
 128                         if ( $module ) {
 129                                 $module->setFileDependencies( $context, ResourceLoaderModule::expandRelativePaths(
 130                                         FormatJson::decode( $row->md_deps, true )
 131                                 ) );
 132                                 $modulesWithDeps[] = $row->md_module;
 133                         }
 134                 }
 135                 // Register the absence of a dependency row too
 136                 foreach ( array_diff( $moduleNames, $modulesWithDeps ) as $name ) {
 137                         $module = $this->getModule( $name );
 138                         if ( $module ) {
 139                                 $this->getModule( $name )->setFileDependencies( $context, [] );
 140                         }
 141                 }
 142
 143                 // Prime in-object cache for message blobs for modules with messages
 144                 $modules = [];
 145                 foreach ( $moduleNames as $name ) {
 146                         $module = $this->getModule( $name );
 147                         if ( $module && $module->getMessages() ) {
 148                                 $modules[$name] = $module;
 149                         }
 150                 }
 151                 $store = $this->getMessageBlobStore();
 152                 $blobs = $store->getBlobs( $modules, $lang );
 153                 foreach ( $blobs as $name => $blob ) {
 154                         $modules[$name]->setMessageBlob( $blob, $lang );
 155                 }
 156         }
 157
 158         /**
 159          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 160          *
 161          * Available filters are:
 162          *
 163          *    - minify-js \see JavaScriptMinifier::minify
 164          *    - minify-css \see CSSMin::minify
 165          *
 166          * If $data is empty, only contains whitespace or the filter was unknown,
 167          * $data is returned unmodified.
 168          *
 169          * @param string $filter Name of filter to run
 170          * @param string $data Text to filter, such as JavaScript or CSS text
 171          * @param array $options Keys:
 172          *  - (bool) cache: Whether to allow caching this data. Default: true.
 173          * @return string Filtered data, or a comment containing an error message
 174          */
 175         public static function filter( $filter, $data, array $options = [] ) {
 176                 if ( strpos( $data, ResourceLoader::FILTER_NOMIN ) !== false ) {
 177                         return $data;
 178                 }
 179
 180                 if ( isset( $options['cache'] ) && $options['cache'] === false ) {
 181                         return self::applyFilter( $filter, $data );
 182                 }
 183
 184                 $stats = RequestContext::getMain()->getStats();
 185                 $cache = ObjectCache::getLocalServerInstance( CACHE_ANYTHING );
 186
 187                 $key = $cache->makeGlobalKey(
 188                         'resourceloader',
 189                         'filter',
 190                         $filter,
 191                         self::$filterCacheVersion, md5( $data )
 192                 );
 193
 194                 $result = $cache->get( $key );
 195                 if ( $result === false ) {
 196                         $stats->increment( "resourceloader_cache.$filter.miss" );
 197                         $result = self::applyFilter( $filter, $data );
 198                         $cache->set( $key, $result, 24 * 3600 );
 199                 } else {
 200                         $stats->increment( "resourceloader_cache.$filter.hit" );
 201                 }
 202                 if ( $result === null ) {
 203                         // Cached failure
 204                         $result = $data;
 205                 }
 206
 207                 return $result;
 208         }
 209
 210         private static function applyFilter( $filter, $data ) {
 211                 $data = trim( $data );
 212                 if ( $data ) {
 213                         try {
 214                                 $data = ( $filter === 'minify-css' )
 215                                         ? CSSMin::minify( $data )
 216                                         : JavaScriptMinifier::minify( $data );
 217                         } catch ( Exception $e ) {
 218                                 MWExceptionHandler::logException( $e );
 219                                 return null;
 220                         }
 221                 }
 222                 return $data;
 223         }
 224
 225         /* Methods */
 226
 227         /**
 228          * Register core modules and runs registration hooks.
 229          * @param Config $config [optional]
 230          * @param LoggerInterface $logger [optional]
 231          */
 232         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 233                 global $IP;
 234
 235                 $this->logger = $logger ?: new NullLogger();
 236
 237                 if ( !$config ) {
 238                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 239                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 240                 }
 241                 $this->config = $config;
 242
 243                 // Add 'local' source first
 244                 $this->addSource( 'local', wfScript( 'load' ) );
 245
 246                 // Add other sources
 247                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 248
 249                 // Register core modules
 250                 $this->register( include "$IP/resources/Resources.php" );
 251                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 252                 // Register extension modules
 253                 $this->register( $config->get( 'ResourceModules' ) );
 254                 Hooks::run( 'ResourceLoaderRegisterModules', [ &$this ] );
 255
 256                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 257                         $this->registerTestModules();
 258                 }
 259
 260                 $this->setMessageBlobStore( new MessageBlobStore( $this, $this->logger ) );
 261         }
 262
 263         /**
 264          * @return Config
 265          */
 266         public function getConfig() {
 267                 return $this->config;
 268         }
 269
 270         /**
 271          * @since 1.26
 272          * @param LoggerInterface $logger
 273          */
 274         public function setLogger( LoggerInterface $logger ) {
 275                 $this->logger = $logger;
 276         }
 277
 278         /**
 279          * @since 1.27
 280          * @return LoggerInterface
 281          */
 282         public function getLogger() {
 283                 return $this->logger;
 284         }
 285
 286         /**
 287          * @since 1.26
 288          * @return MessageBlobStore
 289          */
 290         public function getMessageBlobStore() {
 291                 return $this->blobStore;
 292         }
 293
 294         /**
 295          * @since 1.25
 296          * @param MessageBlobStore $blobStore
 297          */
 298         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 299                 $this->blobStore = $blobStore;
 300         }
 301
 302         /**
 303          * Register a module with the ResourceLoader system.
 304          *
 305          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 306          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 307          *   this may also be a ResourceLoaderModule object. Optional when using
 308          *   multiple-registration calling style.
 309          * @throws MWException If a duplicate module registration is attempted
 310          * @throws MWException If a module name contains illegal characters (pipes or commas)
 311          * @throws MWException If something other than a ResourceLoaderModule is being registered
 312          * @return bool False if there were any errors, in which case one or more modules were
 313          *   not registered
 314          */
 315         public function register( $name, $info = null ) {
 316
 317                 // Allow multiple modules to be registered in one call
 318                 $registrations = is_array( $name ) ? $name : [ $name => $info ];
 319                 foreach ( $registrations as $name => $info ) {
 320                         // Warn on duplicate registrations
 321                         if ( isset( $this->moduleInfos[$name] ) ) {
 322                                 // A module has already been registered by this name
 323                                 $this->logger->warning(
 324                                         'ResourceLoader duplicate registration warning. ' .
 325                                         'Another module has already been registered as ' . $name
 326                                 );
 327                         }
 328
 329                         // Check $name for validity
 330                         if ( !self::isValidModuleName( $name ) ) {
 331                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 332                                         . "see ResourceLoader::isValidModuleName()" );
 333                         }
 334
 335                         // Attach module
 336                         if ( $info instanceof ResourceLoaderModule ) {
 337                                 $this->moduleInfos[$name] = [ 'object' => $info ];
 338                                 $info->setName( $name );
 339                                 $this->modules[$name] = $info;
 340                         } elseif ( is_array( $info ) ) {
 341                                 // New calling convention
 342                                 $this->moduleInfos[$name] = $info;
 343                         } else {
 344                                 throw new MWException(
 345                                         'ResourceLoader module info type error for module \'' . $name .
 346                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 347                                 );
 348                         }
 349
 350                         // Last-minute changes
 351
 352                         // Apply custom skin-defined styles to existing modules.
 353                         if ( $this->isFileModule( $name ) ) {
 354                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 355                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 356                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 357                                                 continue;
 358                                         }
 359
 360                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 361                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 362                                         if ( isset( $skinStyles[$name] ) ) {
 363                                                 $paths = (array)$skinStyles[$name];
 364                                                 $styleFiles = [];
 365                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 366                                                 $paths = (array)$skinStyles['+' . $name];
 367                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 368                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 369                                                         [];
 370                                         } else {
 371                                                 continue;
 372                                         }
 373
 374                                         // Add new file paths, remapping them to refer to our directories and not use settings
 375                                         // from the module we're modifying, which come from the base definition.
 376                                         list( $localBasePath, $remoteBasePath ) =
 377                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 378
 379                                         foreach ( $paths as $path ) {
 380                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 381                                         }
 382
 383                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 384                                 }
 385                         }
 386                 }
 387
 388         }
 389
 390         /**
 391          */
 392         public function registerTestModules() {
 393                 global $IP;
 394
 395                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 396                         throw new MWException( 'Attempt to register JavaScript test modules '
 397                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 398                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 399                 }
 400
 401                 // Get core test suites
 402                 $testModules = [];
 403                 $testModules['qunit'] = [];
 404                 // Get other test suites (e.g. from extensions)
 405                 Hooks::run( 'ResourceLoaderTestModules', [ &$testModules, &$this ] );
 406
 407                 // Add the testrunner (which configures QUnit) to the dependencies.
 408                 // Since it must be ready before any of the test suites are executed.
 409                 foreach ( $testModules['qunit'] as &$module ) {
 410                         // Make sure all test modules are top-loading so that when QUnit starts
 411                         // on document-ready, it will run once and finish. If some tests arrive
 412                         // later (possibly after QUnit has already finished) they will be ignored.
 413                         $module['position'] = 'top';
 414                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 415                 }
 416
 417                 $testModules['qunit'] =
 418                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 419
 420                 foreach ( $testModules as $id => $names ) {
 421                         // Register test modules
 422                         $this->register( $testModules[$id] );
 423
 424                         // Keep track of their names so that they can be loaded together
 425                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 426                 }
 427
 428         }
 429
 430         /**
 431          * Add a foreign source of modules.
 432          *
 433          * Source IDs are typically the same as the Wiki ID or database name (e.g. lowercase a-z).
 434          *
 435          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 436          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 437          *  backwards-compatibility.
 438          * @throws MWException
 439          */
 440         public function addSource( $id, $loadUrl = null ) {
 441                 // Allow multiple sources to be registered in one call
 442                 if ( is_array( $id ) ) {
 443                         foreach ( $id as $key => $value ) {
 444                                 $this->addSource( $key, $value );
 445                         }
 446                         return;
 447                 }
 448
 449                 // Disallow duplicates
 450                 if ( isset( $this->sources[$id] ) ) {
 451                         throw new MWException(
 452                                 'ResourceLoader duplicate source addition error. ' .
 453                                 'Another source has already been registered as ' . $id
 454                         );
 455                 }
 456
 457                 // Pre 1.24 backwards-compatibility
 458                 if ( is_array( $loadUrl ) ) {
 459                         if ( !isset( $loadUrl['loadScript'] ) ) {
 460                                 throw new MWException(
 461                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 462                                 );
 463                         }
 464
 465                         $loadUrl = $loadUrl['loadScript'];
 466                 }
 467
 468                 $this->sources[$id] = $loadUrl;
 469         }
 470
 471         /**
 472          * Get a list of module names.
 473          *
 474          * @return array List of module names
 475          */
 476         public function getModuleNames() {
 477                 return array_keys( $this->moduleInfos );
 478         }
 479
 480         /**
 481          * Get a list of test module names for one (or all) frameworks.
 482          *
 483          * If the given framework id is unknkown, or if the in-object variable is not an array,
 484          * then it will return an empty array.
 485          *
 486          * @param string $framework Get only the test module names for one
 487          *   particular framework (optional)
 488          * @return array
 489          */
 490         public function getTestModuleNames( $framework = 'all' ) {
 491                 /** @todo api siteinfo prop testmodulenames modulenames */
 492                 if ( $framework == 'all' ) {
 493                         return $this->testModuleNames;
 494                 } elseif ( isset( $this->testModuleNames[$framework] )
 495                         && is_array( $this->testModuleNames[$framework] )
 496                 ) {
 497                         return $this->testModuleNames[$framework];
 498                 } else {
 499                         return [];
 500                 }
 501         }
 502
 503         /**
 504          * Check whether a ResourceLoader module is registered
 505          *
 506          * @since 1.25
 507          * @param string $name
 508          * @return bool
 509          */
 510         public function isModuleRegistered( $name ) {
 511                 return isset( $this->moduleInfos[$name] );
 512         }
 513
 514         /**
 515          * Get the ResourceLoaderModule object for a given module name.
 516          *
 517          * If an array of module parameters exists but a ResourceLoaderModule object has not
 518          * yet been instantiated, this method will instantiate and cache that object such that
 519          * subsequent calls simply return the same object.
 520          *
 521          * @param string $name Module name
 522          * @return ResourceLoaderModule|null If module has been registered, return a
 523          *  ResourceLoaderModule instance. Otherwise, return null.
 524          */
 525         public function getModule( $name ) {
 526                 if ( !isset( $this->modules[$name] ) ) {
 527                         if ( !isset( $this->moduleInfos[$name] ) ) {
 528                                 // No such module
 529                                 return null;
 530                         }
 531                         // Construct the requested object
 532                         $info = $this->moduleInfos[$name];
 533                         /** @var ResourceLoaderModule $object */
 534                         if ( isset( $info['object'] ) ) {
 535                                 // Object given in info array
 536                                 $object = $info['object'];
 537                         } else {
 538                                 if ( !isset( $info['class'] ) ) {
 539                                         $class = 'ResourceLoaderFileModule';
 540                                 } else {
 541                                         $class = $info['class'];
 542                                 }
 543                                 /** @var ResourceLoaderModule $object */
 544                                 $object = new $class( $info );
 545                                 $object->setConfig( $this->getConfig() );
 546                                 $object->setLogger( $this->logger );
 547                         }
 548                         $object->setName( $name );
 549                         $this->modules[$name] = $object;
 550                 }
 551
 552                 return $this->modules[$name];
 553         }
 554
 555         /**
 556          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 557          *
 558          * @param string $name Module name
 559          * @return bool
 560          */
 561         protected function isFileModule( $name ) {
 562                 if ( !isset( $this->moduleInfos[$name] ) ) {
 563                         return false;
 564                 }
 565                 $info = $this->moduleInfos[$name];
 566                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 567                         return false;
 568                 }
 569                 return true;
 570         }
 571
 572         /**
 573          * Get the list of sources.
 574          *
 575          * @return array Like array( id => load.php url, .. )
 576          */
 577         public function getSources() {
 578                 return $this->sources;
 579         }
 580
 581         /**
 582          * Get the URL to the load.php endpoint for the given
 583          * ResourceLoader source
 584          *
 585          * @since 1.24
 586          * @param string $source
 587          * @throws MWException On an invalid $source name
 588          * @return string
 589          */
 590         public function getLoadScript( $source ) {
 591                 if ( !isset( $this->sources[$source] ) ) {
 592                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 593                 }
 594                 return $this->sources[$source];
 595         }
 596
 597         /**
 598          * @since 1.26
 599          * @param string $value
 600          * @return string Hash
 601          */
 602         public static function makeHash( $value ) {
 603                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 604                 // The first 8 chars of a base64 encoded digest represent the same binary as
 605                 // the first 12 chars of a hex encoded digest.
 606                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 607         }
 608
 609         /**
 610          * Helper method to get and combine versions of multiple modules.
 611          *
 612          * @since 1.26
 613          * @param ResourceLoaderContext $context
 614          * @param array $modules List of ResourceLoaderModule objects
 615          * @return string Hash
 616          */
 617         public function getCombinedVersion( ResourceLoaderContext $context, array $modules ) {
 618                 if ( !$modules ) {
 619                         return '';
 620                 }
 621                 $hashes = array_map( function ( $module ) use ( $context ) {
 622                         return $this->getModule( $module )->getVersionHash( $context );
 623                 }, $modules );
 624                 return self::makeHash( implode( $hashes ) );
 625         }
 626
 627         /**
 628          * Output a response to a load request, including the content-type header.
 629          *
 630          * @param ResourceLoaderContext $context Context in which a response should be formed
 631          */
 632         public function respond( ResourceLoaderContext $context ) {
 633                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 634                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 635                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 636                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 637                 // the whole thing in our own output buffer to be sure the active buffer
 638                 // doesn't use ob_gzhandler.
 639                 // See http://bugs.php.net/bug.php?id=36514
 640                 ob_start();
 641
 642                 // Find out which modules are missing and instantiate the others
 643                 $modules = [];
 644                 $missing = [];
 645                 foreach ( $context->getModules() as $name ) {
 646                         $module = $this->getModule( $name );
 647                         if ( $module ) {
 648                                 // Do not allow private modules to be loaded from the web.
 649                                 // This is a security issue, see bug 34907.
 650                                 if ( $module->getGroup() === 'private' ) {
 651                                         $this->logger->debug( "Request for private module '$name' denied" );
 652                                         $this->errors[] = "Cannot show private module \"$name\"";
 653                                         continue;
 654                                 }
 655                                 $modules[$name] = $module;
 656                         } else {
 657                                 $missing[] = $name;
 658                         }
 659                 }
 660
 661                 try {
 662                         // Preload for getCombinedVersion() and for batch makeModuleResponse()
 663                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 664                 } catch ( Exception $e ) {
 665                         MWExceptionHandler::logException( $e );
 666                         $this->logger->warning( 'Preloading module info failed: {exception}', [
 667                                 'exception' => $e
 668                         ] );
 669                         $this->errors[] = self::formatExceptionNoComment( $e );
 670                 }
 671
 672                 // Combine versions to propagate cache invalidation
 673                 $versionHash = '';
 674                 try {
 675                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 676                 } catch ( Exception $e ) {
 677                         MWExceptionHandler::logException( $e );
 678                         $this->logger->warning( 'Calculating version hash failed: {exception}', [
 679                                 'exception' => $e
 680                         ] );
 681                         $this->errors[] = self::formatExceptionNoComment( $e );
 682                 }
 683
 684                 // See RFC 2616 § 3.11 Entity Tags
 685                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 686                 $etag = 'W/"' . $versionHash . '"';
 687
 688                 // Try the client-side cache first
 689                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 690                         return; // output handled (buffers cleared)
 691                 }
 692
 693                 // Use file cache if enabled and available...
 694                 if ( $this->config->get( 'UseFileCache' ) ) {
 695                         $fileCache = ResourceFileCache::newFromContext( $context );
 696                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 697                                 return; // output handled
 698                         }
 699                 }
 700
 701                 // Generate a response
 702                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 703
 704                 // Capture any PHP warnings from the output buffer and append them to the
 705                 // error list if we're in debug mode.
 706                 if ( $context->getDebug() ) {
 707                         $warnings = ob_get_contents();
 708                         if ( strlen( $warnings ) ) {
 709                                 $this->errors[] = $warnings;
 710                         }
 711                 }
 712
 713                 // Save response to file cache unless there are errors
 714                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 715                         // Cache single modules and images...and other requests if there are enough hits
 716                         if ( ResourceFileCache::useFileCache( $context ) ) {
 717                                 if ( $fileCache->isCacheWorthy() ) {
 718                                         $fileCache->saveText( $response );
 719                                 } else {
 720                                         $fileCache->incrMissesRecent( $context->getRequest() );
 721                                 }
 722                         }
 723                 }
 724
 725                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 726
 727                 // Remove the output buffer and output the response
 728                 ob_end_clean();
 729
 730                 if ( $context->getImageObj() && $this->errors ) {
 731                         // We can't show both the error messages and the response when it's an image.
 732                         $response = implode( "\n\n", $this->errors );
 733                 } elseif ( $this->errors ) {
 734                         $errorText = implode( "\n\n", $this->errors );
 735                         $errorResponse = self::makeComment( $errorText );
 736                         if ( $context->shouldIncludeScripts() ) {
 737                                 $errorResponse .= 'if (window.console && console.error) {'
 738                                         . Xml::encodeJsCall( 'console.error', [ $errorText ] )
 739                                         . "}\n";
 740                         }
 741
 742                         // Prepend error info to the response
 743                         $response = $errorResponse . $response;
 744                 }
 745
 746                 $this->errors = [];
 747                 echo $response;
 748
 749         }
 750
 751         /**
 752          * Send main response headers to the client.
 753          *
 754          * Deals with Content-Type, CORS (for stylesheets), and caching.
 755          *
 756          * @param ResourceLoaderContext $context
 757          * @param string $etag ETag header value
 758          * @param bool $errors Whether there are errors in the response
 759          * @return void
 760          */
 761         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 762                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 763                 // If a version wasn't specified we need a shorter expiry time for updates
 764                 // to propagate to clients quickly
 765                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 766                 if ( is_null( $context->getVersion() ) || $errors ) {
 767                         $maxage = $rlMaxage['unversioned']['client'];
 768                         $smaxage = $rlMaxage['unversioned']['server'];
 769                 // If a version was specified we can use a longer expiry time since changing
 770                 // version numbers causes cache misses
 771                 } else {
 772                         $maxage = $rlMaxage['versioned']['client'];
 773                         $smaxage = $rlMaxage['versioned']['server'];
 774                 }
 775                 if ( $context->getImageObj() ) {
 776                         // Output different headers if we're outputting textual errors.
 777                         if ( $errors ) {
 778                                 header( 'Content-Type: text/plain; charset=utf-8' );
 779                         } else {
 780                                 $context->getImageObj()->sendResponseHeaders( $context );
 781                         }
 782                 } elseif ( $context->getOnly() === 'styles' ) {
 783                         header( 'Content-Type: text/css; charset=utf-8' );
 784                         header( 'Access-Control-Allow-Origin: *' );
 785                 } else {
 786                         header( 'Content-Type: text/javascript; charset=utf-8' );
 787                 }
 788                 // See RFC 2616 § 14.19 ETag
 789                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 790                 header( 'ETag: ' . $etag );
 791                 if ( $context->getDebug() ) {
 792                         // Do not cache debug responses
 793                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 794                         header( 'Pragma: no-cache' );
 795                 } else {
 796                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 797                         $exp = min( $maxage, $smaxage );
 798                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 799                 }
 800         }
 801
 802         /**
 803          * Respond with HTTP 304 Not Modified if appropiate.
 804          *
 805          * If there's an If-None-Match header, respond with a 304 appropriately
 806          * and clear out the output buffer. If the client cache is too old then do nothing.
 807          *
 808          * @param ResourceLoaderContext $context
 809          * @param string $etag ETag header value
 810          * @return bool True if HTTP 304 was sent and output handled
 811          */
 812         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 813                 // See RFC 2616 § 14.26 If-None-Match
 814                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 815                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 816                 // Never send 304s in debug mode
 817                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 818                         // There's another bug in ob_gzhandler (see also the comment at
 819                         // the top of this function) that causes it to gzip even empty
 820                         // responses, meaning it's impossible to produce a truly empty
 821                         // response (because the gzip header is always there). This is
 822                         // a problem because 304 responses have to be completely empty
 823                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 824                         // See also http://bugs.php.net/bug.php?id=51579
 825                         // To work around this, we tear down all output buffering before
 826                         // sending the 304.
 827                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 828
 829                         HttpStatus::header( 304 );
 830
 831                         $this->sendResponseHeaders( $context, $etag, false );
 832                         return true;
 833                 }
 834                 return false;
 835         }
 836
 837         /**
 838          * Send out code for a response from file cache if possible.
 839          *
 840          * @param ResourceFileCache $fileCache Cache object for this request URL
 841          * @param ResourceLoaderContext $context Context in which to generate a response
 842          * @param string $etag ETag header value
 843          * @return bool If this found a cache file and handled the response
 844          */
 845         protected function tryRespondFromFileCache(
 846                 ResourceFileCache $fileCache,
 847                 ResourceLoaderContext $context,
 848                 $etag
 849         ) {
 850                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 851                 // Buffer output to catch warnings.
 852                 ob_start();
 853                 // Get the maximum age the cache can be
 854                 $maxage = is_null( $context->getVersion() )
 855                         ? $rlMaxage['unversioned']['server']
 856                         : $rlMaxage['versioned']['server'];
 857                 // Minimum timestamp the cache file must have
 858                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 859                 if ( !$good ) {
 860                         try { // RL always hits the DB on file cache miss...
 861                                 wfGetDB( DB_SLAVE );
 862                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 863                                 $good = $fileCache->isCacheGood(); // cache existence check
 864                         }
 865                 }
 866                 if ( $good ) {
 867                         $ts = $fileCache->cacheTimestamp();
 868                         // Send content type and cache headers
 869                         $this->sendResponseHeaders( $context, $etag, false );
 870                         $response = $fileCache->fetchText();
 871                         // Capture any PHP warnings from the output buffer and append them to the
 872                         // response in a comment if we're in debug mode.
 873                         if ( $context->getDebug() ) {
 874                                 $warnings = ob_get_contents();
 875                                 if ( strlen( $warnings ) ) {
 876                                         $response = self::makeComment( $warnings ) . $response;
 877                                 }
 878                         }
 879                         // Remove the output buffer and output the response
 880                         ob_end_clean();
 881                         echo $response . "\n/* Cached {$ts} */";
 882                         return true; // cache hit
 883                 }
 884                 // Clear buffer
 885                 ob_end_clean();
 886
 887                 return false; // cache miss
 888         }
 889
 890         /**
 891          * Generate a CSS or JS comment block.
 892          *
 893          * Only use this for public data, not error message details.
 894          *
 895          * @param string $text
 896          * @return string
 897          */
 898         public static function makeComment( $text ) {
 899                 $encText = str_replace( '*/', '* /', $text );
 900                 return "/*\n$encText\n*/\n";
 901         }
 902
 903         /**
 904          * Handle exception display.
 905          *
 906          * @param Exception $e Exception to be shown to the user
 907          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 908          */
 909         public static function formatException( $e ) {
 910                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 911         }
 912
 913         /**
 914          * Handle exception display.
 915          *
 916          * @since 1.25
 917          * @param Exception $e Exception to be shown to the user
 918          * @return string Sanitized text that can be returned to the user
 919          */
 920         protected static function formatExceptionNoComment( $e ) {
 921                 global $wgShowExceptionDetails;
 922
 923                 if ( !$wgShowExceptionDetails ) {
 924                         return MWExceptionHandler::getPublicLogMessage( $e );
 925                 }
 926
 927                 return MWExceptionHandler::getLogMessage( $e );
 928         }
 929
 930         /**
 931          * Generate code for a response.
 932          *
 933          * @param ResourceLoaderContext $context Context in which to generate a response
 934          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 935          * @param string[] $missing List of requested module names that are unregistered (optional)
 936          * @return string Response data
 937          */
 938         public function makeModuleResponse( ResourceLoaderContext $context,
 939                 array $modules, array $missing = []
 940         ) {
 941                 $out = '';
 942                 $states = [];
 943
 944                 if ( !count( $modules ) && !count( $missing ) ) {
 945                         return <<<MESSAGE
 946 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 947    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 948    no modules were requested. Max made me put this here. */
 949 MESSAGE;
 950                 }
 951
 952                 $image = $context->getImageObj();
 953                 if ( $image ) {
 954                         $data = $image->getImageData( $context );
 955                         if ( $data === false ) {
 956                                 $data = '';
 957                                 $this->errors[] = 'Image generation failed';
 958                         }
 959                         return $data;
 960                 }
 961
 962                 foreach ( $missing as $name ) {
 963                         $states[$name] = 'missing';
 964                 }
 965
 966                 // Generate output
 967                 $isRaw = false;
 968
 969                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
 970
 971                 foreach ( $modules as $name => $module ) {
 972                         try {
 973                                 $content = $module->getModuleContent( $context );
 974                                 $strContent = '';
 975
 976                                 // Append output
 977                                 switch ( $context->getOnly() ) {
 978                                         case 'scripts':
 979                                                 $scripts = $content['scripts'];
 980                                                 if ( is_string( $scripts ) ) {
 981                                                         // Load scripts raw...
 982                                                         $strContent = $scripts;
 983                                                 } elseif ( is_array( $scripts ) ) {
 984                                                         // ...except when $scripts is an array of URLs
 985                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, [], [], [] );
 986                                                 }
 987                                                 break;
 988                                         case 'styles':
 989                                                 $styles = $content['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                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 994                                                 break;
 995                                         default:
 996                                                 $strContent = self::makeLoaderImplementScript(
 997                                                         $name,
 998                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
 999                                                         isset( $content['styles'] ) ? $content['styles'] : [],
1000                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : [],
1001                                                         isset( $content['templates'] ) ? $content['templates'] : []
1002                                                 );
1003                                                 break;
1004                                 }
1005
1006                                 if ( !$context->getDebug() ) {
1007                                         $strContent = self::filter( $filter, $strContent );
1008                                 }
1009
1010                                 $out .= $strContent;
1011
1012                         } catch ( Exception $e ) {
1013                                 MWExceptionHandler::logException( $e );
1014                                 $this->logger->warning( 'Generating module package failed: {exception}', [
1015                                         'exception' => $e
1016                                 ] );
1017                                 $this->errors[] = self::formatExceptionNoComment( $e );
1018
1019                                 // Respond to client with error-state instead of module implementation
1020                                 $states[$name] = 'error';
1021                                 unset( $modules[$name] );
1022                         }
1023                         $isRaw |= $module->isRaw();
1024                 }
1025
1026                 // Update module states
1027                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1028                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1029                                 // Set the state of modules loaded as only scripts to ready as
1030                                 // they don't have an mw.loader.implement wrapper that sets the state
1031                                 foreach ( $modules as $name => $module ) {
1032                                         $states[$name] = 'ready';
1033                                 }
1034                         }
1035
1036                         // Set the state of modules we didn't respond to with mw.loader.implement
1037                         if ( count( $states ) ) {
1038                                 $stateScript = self::makeLoaderStateScript( $states );
1039                                 if ( !$context->getDebug() ) {
1040                                         $stateScript = self::filter( 'minify-js', $stateScript );
1041                                 }
1042                                 $out .= $stateScript;
1043                         }
1044                 } else {
1045                         if ( count( $states ) ) {
1046                                 $this->errors[] = 'Problematic modules: ' .
1047                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1048                         }
1049                 }
1050
1051                 return $out;
1052         }
1053
1054         /**
1055          * Get names of modules that use a certain message.
1056          *
1057          * @param string $messageKey
1058          * @return array List of module names
1059          */
1060         public function getModulesByMessage( $messageKey ) {
1061                 $moduleNames = [];
1062                 foreach ( $this->getModuleNames() as $moduleName ) {
1063                         $module = $this->getModule( $moduleName );
1064                         if ( in_array( $messageKey, $module->getMessages() ) ) {
1065                                 $moduleNames[] = $moduleName;
1066                         }
1067                 }
1068                 return $moduleNames;
1069         }
1070
1071         /* Static Methods */
1072
1073         /**
1074          * Return JS code that calls mw.loader.implement with given module properties.
1075          *
1076          * @param string $name Module name
1077          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1078          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1079          *   to CSS files keyed by media type
1080          * @param mixed $messages List of messages associated with this module. May either be an
1081          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1082          *   the same data, wrapped in an XmlJsCode object.
1083          * @param array $templates Keys are name of templates and values are the source of
1084          *   the template.
1085          * @throws MWException
1086          * @return string
1087          */
1088         public static function makeLoaderImplementScript(
1089                 $name, $scripts, $styles, $messages, $templates
1090         ) {
1091                 if ( is_string( $scripts ) ) {
1092                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1093                         // Transportation as string instructs mw.loader.implement to use globalEval.
1094                         if ( $name === 'site' || $name === 'user' ) {
1095                                 // Minify manually because the general makeModuleResponse() minification won't be
1096                                 // effective here due to the script being a string instead of a function. (T107377)
1097                                 if ( !ResourceLoader::inDebugMode() ) {
1098                                         $scripts = self::filter( 'minify-js', $scripts );
1099                                 }
1100                         } else {
1101                                 $scripts = new XmlJsCode( "function ( $, jQuery, require, module ) {\n{$scripts}\n}" );
1102                         }
1103                 } elseif ( !is_array( $scripts ) ) {
1104                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1105                 }
1106                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1107                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1108                 // of "{}". Force them to objects.
1109                 $module = [
1110                         $name,
1111                         $scripts,
1112                         (object)$styles,
1113                         (object)$messages,
1114                         (object)$templates,
1115                 ];
1116                 self::trimArray( $module );
1117
1118                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1119         }
1120
1121         /**
1122          * Returns JS code which, when called, will register a given list of messages.
1123          *
1124          * @param mixed $messages Either an associative array mapping message key to value, or a
1125          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1126          * @return string
1127          */
1128         public static function makeMessageSetScript( $messages ) {
1129                 return Xml::encodeJsCall(
1130                         'mw.messages.set',
1131                         [ (object)$messages ],
1132                         ResourceLoader::inDebugMode()
1133                 );
1134         }
1135
1136         /**
1137          * Combines an associative array mapping media type to CSS into a
1138          * single stylesheet with "@media" blocks.
1139          *
1140          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1141          * @return array
1142          */
1143         public static function makeCombinedStyles( array $stylePairs ) {
1144                 $out = [];
1145                 foreach ( $stylePairs as $media => $styles ) {
1146                         // ResourceLoaderFileModule::getStyle can return the styles
1147                         // as a string or an array of strings. This is to allow separation in
1148                         // the front-end.
1149                         $styles = (array)$styles;
1150                         foreach ( $styles as $style ) {
1151                                 $style = trim( $style );
1152                                 // Don't output an empty "@media print { }" block (bug 40498)
1153                                 if ( $style !== '' ) {
1154                                         // Transform the media type based on request params and config
1155                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1156                                         $media = OutputPage::transformCssMedia( $media );
1157
1158                                         if ( $media === '' || $media == 'all' ) {
1159                                                 $out[] = $style;
1160                                         } elseif ( is_string( $media ) ) {
1161                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1162                                         }
1163                                         // else: skip
1164                                 }
1165                         }
1166                 }
1167                 return $out;
1168         }
1169
1170         /**
1171          * Returns a JS call to mw.loader.state, which sets the state of a
1172          * module or modules to a given value. Has two calling conventions:
1173          *
1174          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1175          *         Set the state of a single module called $name to $state
1176          *
1177          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1178          *         Set the state of modules with the given names to the given states
1179          *
1180          * @param string $name
1181          * @param string $state
1182          * @return string
1183          */
1184         public static function makeLoaderStateScript( $name, $state = null ) {
1185                 if ( is_array( $name ) ) {
1186                         return Xml::encodeJsCall(
1187                                 'mw.loader.state',
1188                                 [ $name ],
1189                                 ResourceLoader::inDebugMode()
1190                         );
1191                 } else {
1192                         return Xml::encodeJsCall(
1193                                 'mw.loader.state',
1194                                 [ $name, $state ],
1195                                 ResourceLoader::inDebugMode()
1196                         );
1197                 }
1198         }
1199
1200         /**
1201          * Returns JS code which calls the script given by $script. The script will
1202          * be called with local variables name, version, dependencies and group,
1203          * which will have values corresponding to $name, $version, $dependencies
1204          * and $group as supplied.
1205          *
1206          * @param string $name Module name
1207          * @param string $version Module version hash
1208          * @param array $dependencies List of module names on which this module depends
1209          * @param string $group Group which the module is in.
1210          * @param string $source Source of the module, or 'local' if not foreign.
1211          * @param string $script JavaScript code
1212          * @return string
1213          */
1214         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1215                 $group, $source, $script
1216         ) {
1217                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1218                 return Xml::encodeJsCall(
1219                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1220                         [ $name, $version, $dependencies, $group, $source ],
1221                         ResourceLoader::inDebugMode()
1222                 );
1223         }
1224
1225         private static function isEmptyObject( stdClass $obj ) {
1226                 foreach ( $obj as $key => $value ) {
1227                         return false;
1228                 }
1229                 return true;
1230         }
1231
1232         /**
1233          * Remove empty values from the end of an array.
1234          *
1235          * Values considered empty:
1236          *
1237          * - null
1238          * - array()
1239          * - new XmlJsCode( '{}' )
1240          * - new stdClass() // (object) array()
1241          *
1242          * @param Array $array
1243          */
1244         private static function trimArray( array &$array ) {
1245                 $i = count( $array );
1246                 while ( $i-- ) {
1247                         if ( $array[$i] === null
1248                                 || $array[$i] === []
1249                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1250                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1251                         ) {
1252                                 unset( $array[$i] );
1253                         } else {
1254                                 break;
1255                         }
1256                 }
1257         }
1258
1259         /**
1260          * Returns JS code which calls mw.loader.register with the given
1261          * parameters. Has three calling conventions:
1262          *
1263          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1264          *        $dependencies, $group, $source, $skip
1265          *     ):
1266          *        Register a single module.
1267          *
1268          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1269          *        Register modules with the given names.
1270          *
1271          *   - ResourceLoader::makeLoaderRegisterScript( array(
1272          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1273          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1274          *        ...
1275          *     ) ):
1276          *        Registers modules with the given names and parameters.
1277          *
1278          * @param string $name Module name
1279          * @param string $version Module version hash
1280          * @param array $dependencies List of module names on which this module depends
1281          * @param string $group Group which the module is in
1282          * @param string $source Source of the module, or 'local' if not foreign
1283          * @param string $skip Script body of the skip function
1284          * @return string
1285          */
1286         public static function makeLoaderRegisterScript( $name, $version = null,
1287                 $dependencies = null, $group = null, $source = null, $skip = null
1288         ) {
1289                 if ( is_array( $name ) ) {
1290                         // Build module name index
1291                         $index = [];
1292                         foreach ( $name as $i => &$module ) {
1293                                 $index[$module[0]] = $i;
1294                         }
1295
1296                         // Transform dependency names into indexes when possible, they will be resolved by
1297                         // mw.loader.register on the other end
1298                         foreach ( $name as &$module ) {
1299                                 if ( isset( $module[2] ) ) {
1300                                         foreach ( $module[2] as &$dependency ) {
1301                                                 if ( isset( $index[$dependency] ) ) {
1302                                                         $dependency = $index[$dependency];
1303                                                 }
1304                                         }
1305                                 }
1306                         }
1307
1308                         array_walk( $name, [ 'self', 'trimArray' ] );
1309
1310                         return Xml::encodeJsCall(
1311                                 'mw.loader.register',
1312                                 [ $name ],
1313                                 ResourceLoader::inDebugMode()
1314                         );
1315                 } else {
1316                         $registration = [ $name, $version, $dependencies, $group, $source, $skip ];
1317                         self::trimArray( $registration );
1318                         return Xml::encodeJsCall(
1319                                 'mw.loader.register',
1320                                 $registration,
1321                                 ResourceLoader::inDebugMode()
1322                         );
1323                 }
1324         }
1325
1326         /**
1327          * Returns JS code which calls mw.loader.addSource() with the given
1328          * parameters. Has two calling conventions:
1329          *
1330          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1331          *       Register a single source
1332          *
1333          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1334          *       Register sources with the given IDs and properties.
1335          *
1336          * @param string $id Source ID
1337          * @param array $properties Source properties (see addSource())
1338          * @return string
1339          */
1340         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1341                 if ( is_array( $id ) ) {
1342                         return Xml::encodeJsCall(
1343                                 'mw.loader.addSource',
1344                                 [ $id ],
1345                                 ResourceLoader::inDebugMode()
1346                         );
1347                 } else {
1348                         return Xml::encodeJsCall(
1349                                 'mw.loader.addSource',
1350                                 [ $id, $properties ],
1351                                 ResourceLoader::inDebugMode()
1352                         );
1353                 }
1354         }
1355
1356         /**
1357          * Returns JS code which runs given JS code if the client-side framework is
1358          * present.
1359          *
1360          * @deprecated since 1.25; use makeInlineScript instead
1361          * @param string $script JavaScript code
1362          * @return string
1363          */
1364         public static function makeLoaderConditionalScript( $script ) {
1365                 return '(window.RLQ=window.RLQ||[]).push(function(){' .
1366                         trim( $script ) . '});';
1367         }
1368
1369         /**
1370          * Construct an inline script tag with given JS code.
1371          *
1372          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1373          * only if the client has adequate support for MediaWiki JavaScript code.
1374          *
1375          * @param string $script JavaScript code
1376          * @return WrappedString HTML
1377          */
1378         public static function makeInlineScript( $script ) {
1379                 $js = self::makeLoaderConditionalScript( $script );
1380                 return new WrappedString(
1381                         Html::inlineScript( $js ),
1382                         '<script>(window.RLQ=window.RLQ||[]).push(function(){',
1383                         '});</script>'
1384                 );
1385         }
1386
1387         /**
1388          * Returns JS code which will set the MediaWiki configuration array to
1389          * the given value.
1390          *
1391          * @param array $configuration List of configuration values keyed by variable name
1392          * @return string
1393          */
1394         public static function makeConfigSetScript( array $configuration ) {
1395                 return Xml::encodeJsCall(
1396                         'mw.config.set',
1397                         [ $configuration ],
1398                         ResourceLoader::inDebugMode()
1399                 );
1400         }
1401
1402         /**
1403          * Convert an array of module names to a packed query string.
1404          *
1405          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1406          * becomes 'foo.bar,baz|bar.baz,quux'
1407          * @param array $modules List of module names (strings)
1408          * @return string Packed query string
1409          */
1410         public static function makePackedModulesString( $modules ) {
1411                 $groups = []; // array( prefix => array( suffixes ) )
1412                 foreach ( $modules as $module ) {
1413                         $pos = strrpos( $module, '.' );
1414                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1415                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1416                         $groups[$prefix][] = $suffix;
1417                 }
1418
1419                 $arr = [];
1420                 foreach ( $groups as $prefix => $suffixes ) {
1421                         $p = $prefix === '' ? '' : $prefix . '.';
1422                         $arr[] = $p . implode( ',', $suffixes );
1423                 }
1424                 $str = implode( '|', $arr );
1425                 return $str;
1426         }
1427
1428         /**
1429          * Determine whether debug mode was requested
1430          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1431          * @return bool
1432          */
1433         public static function inDebugMode() {
1434                 if ( self::$debugMode === null ) {
1435                         global $wgRequest, $wgResourceLoaderDebug;
1436                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1437                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1438                         );
1439                 }
1440                 return self::$debugMode;
1441         }
1442
1443         /**
1444          * Reset static members used for caching.
1445          *
1446          * Global state and $wgRequest are evil, but we're using it right
1447          * now and sometimes we need to be able to force ResourceLoader to
1448          * re-evaluate the context because it has changed (e.g. in the test suite).
1449          */
1450         public static function clearCache() {
1451                 self::$debugMode = null;
1452         }
1453
1454         /**
1455          * Build a load.php URL
1456          *
1457          * @since 1.24
1458          * @param string $source Name of the ResourceLoader source
1459          * @param ResourceLoaderContext $context
1460          * @param array $extraQuery
1461          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1462          */
1463         public function createLoaderURL( $source, ResourceLoaderContext $context,
1464                 $extraQuery = []
1465         ) {
1466                 $query = self::createLoaderQuery( $context, $extraQuery );
1467                 $script = $this->getLoadScript( $source );
1468
1469                 return wfAppendQuery( $script, $query );
1470         }
1471
1472         /**
1473          * Build a load.php URL
1474          * @deprecated since 1.24 Use createLoaderURL() instead
1475          * @param array $modules Array of module names (strings)
1476          * @param string $lang Language code
1477          * @param string $skin Skin name
1478          * @param string|null $user User name. If null, the &user= parameter is omitted
1479          * @param string|null $version Versioning timestamp
1480          * @param bool $debug Whether the request should be in debug mode
1481          * @param string|null $only &only= parameter
1482          * @param bool $printable Printable mode
1483          * @param bool $handheld Handheld mode
1484          * @param array $extraQuery Extra query parameters to add
1485          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1486          */
1487         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1488                 $version = null, $debug = false, $only = null, $printable = false,
1489                 $handheld = false, $extraQuery = []
1490         ) {
1491                 global $wgLoadScript;
1492
1493                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1494                         $only, $printable, $handheld, $extraQuery
1495                 );
1496
1497                 return wfAppendQuery( $wgLoadScript, $query );
1498         }
1499
1500         /**
1501          * Helper for createLoaderURL()
1502          *
1503          * @since 1.24
1504          * @see makeLoaderQuery
1505          * @param ResourceLoaderContext $context
1506          * @param array $extraQuery
1507          * @return array
1508          */
1509         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = [] ) {
1510                 return self::makeLoaderQuery(
1511                         $context->getModules(),
1512                         $context->getLanguage(),
1513                         $context->getSkin(),
1514                         $context->getUser(),
1515                         $context->getVersion(),
1516                         $context->getDebug(),
1517                         $context->getOnly(),
1518                         $context->getRequest()->getBool( 'printable' ),
1519                         $context->getRequest()->getBool( 'handheld' ),
1520                         $extraQuery
1521                 );
1522         }
1523
1524         /**
1525          * Build a query array (array representation of query string) for load.php. Helper
1526          * function for makeLoaderURL().
1527          *
1528          * @param array $modules
1529          * @param string $lang
1530          * @param string $skin
1531          * @param string $user
1532          * @param string $version
1533          * @param bool $debug
1534          * @param string $only
1535          * @param bool $printable
1536          * @param bool $handheld
1537          * @param array $extraQuery
1538          *
1539          * @return array
1540          */
1541         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1542                 $version = null, $debug = false, $only = null, $printable = false,
1543                 $handheld = false, $extraQuery = []
1544         ) {
1545                 $query = [
1546                         'modules' => self::makePackedModulesString( $modules ),
1547                         'lang' => $lang,
1548                         'skin' => $skin,
1549                         'debug' => $debug ? 'true' : 'false',
1550                 ];
1551                 if ( $user !== null ) {
1552                         $query['user'] = $user;
1553                 }
1554                 if ( $version !== null ) {
1555                         $query['version'] = $version;
1556                 }
1557                 if ( $only !== null ) {
1558                         $query['only'] = $only;
1559                 }
1560                 if ( $printable ) {
1561                         $query['printable'] = 1;
1562                 }
1563                 if ( $handheld ) {
1564                         $query['handheld'] = 1;
1565                 }
1566                 $query += $extraQuery;
1567
1568                 // Make queries uniform in order
1569                 ksort( $query );
1570                 return $query;
1571         }
1572
1573         /**
1574          * Check a module name for validity.
1575          *
1576          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1577          * at most 255 bytes.
1578          *
1579          * @param string $moduleName Module name to check
1580          * @return bool Whether $moduleName is a valid module name
1581          */
1582         public static function isValidModuleName( $moduleName ) {
1583                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1584         }
1585
1586         /**
1587          * Returns LESS compiler set up for use with MediaWiki
1588          *
1589          * @since 1.27
1590          * @param array $extraVars Associative array of extra (i.e., other than the
1591          *   globally-configured ones) that should be used for compilation.
1592          * @throws MWException
1593          * @return Less_Parser
1594          */
1595         public function getLessCompiler( $extraVars = [] ) {
1596                 // When called from the installer, it is possible that a required PHP extension
1597                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1598                 // exception (caught by the installer) to prevent a fatal error later on.
1599                 if ( !class_exists( 'Less_Parser' ) ) {
1600                         throw new MWException( 'MediaWiki requires the less.php parser' );
1601                 }
1602
1603                 $parser = new Less_Parser;
1604                 $parser->ModifyVars( array_merge( $this->getLessVars(), $extraVars ) );
1605                 $parser->SetImportDirs(
1606                         array_fill_keys( $this->config->get( 'ResourceLoaderLESSImportPaths' ), '' )
1607                 );
1608                 $parser->SetOption( 'relativeUrls', false );
1609                 $parser->SetCacheDir( $this->config->get( 'CacheDirectory' ) ?: wfTempDir() );
1610
1611                 return $parser;
1612         }
1613
1614         /**
1615          * Get global LESS variables.
1616          *
1617          * @since 1.27
1618          * @return array Map of variable names to string CSS values.
1619          */
1620         public function getLessVars() {
1621                 if ( !$this->lessVars ) {
1622                         $lessVars = $this->config->get( 'ResourceLoaderLESSVars' );
1623                         Hooks::run( 'ResourceLoaderGetLessVars', [ &$lessVars ] );
1624                         $this->lessVars = $lessVars;
1625                 }
1626                 return $this->lessVars;
1627         }
1628 }