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 static $lessVars = null;
  45
  46         /**
  47          * Module name/ResourceLoaderModule object pairs
  48          * @var array
  49          */
  50         protected $modules = array();
  51
  52         /**
  53          * Associative array mapping module name to info associative array
  54          * @var array
  55          */
  56         protected $moduleInfos = array();
  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 = array();
  67
  68         /**
  69          * E.g. array( 'source-id' => 'http://.../load.php' )
  70          * @var array
  71          */
  72         protected $sources = array();
  73
  74         /**
  75          * Errors accumulated during current respond() call.
  76          * @var array
  77          */
  78         protected $errors = array();
  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 $modules List of module names to preload information for
 105          * @param ResourceLoaderContext $context Context to load the information within
 106          */
 107         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
 108                 if ( !count( $modules ) ) {
 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', array( 'md_module', 'md_deps' ), array(
 119                                 'md_module' => $modules,
 120                                 'md_skin' => $vary,
 121                         ), __METHOD__
 122                 );
 123                 // Prime in-object cache values for each module
 124                 $modulesWithDeps = array();
 125                 foreach ( $res as $row ) {
 126                         $module = $this->getModule( $row->md_module );
 127                         if ( $module ) {
 128                                 $module->setFileDependencies( $context, ResourceLoaderModule::expandRelativePaths(
 129                                         FormatJson::decode( $row->md_deps, true )
 130                                 ) );
 131                                 $modulesWithDeps[] = $row->md_module;
 132                         }
 133                 }
 134                 // Register the absence of a dependency row too
 135                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 136                         $module = $this->getModule( $name );
 137                         if ( $module ) {
 138                                 $this->getModule( $name )->setFileDependencies( $context, array() );
 139                         }
 140                 }
 141
 142                 // Get message blob mtimes. Only do this for modules with messages
 143                 $modulesWithMessages = array();
 144                 foreach ( $modules as $name ) {
 145                         $module = $this->getModule( $name );
 146                         if ( $module && count( $module->getMessages() ) ) {
 147                                 $modulesWithMessages[] = $name;
 148                         }
 149                 }
 150                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 151                 if ( count( $modulesWithMessages ) ) {
 152                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 153                                         'mr_resource' => $modulesWithMessages,
 154                                         'mr_lang' => $lang
 155                                 ), __METHOD__
 156                         );
 157                         foreach ( $res as $row ) {
 158                                 $module = $this->getModule( $row->mr_resource );
 159                                 if ( $module ) {
 160                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 161                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 162                                 }
 163                         }
 164                 }
 165                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 166                         $module = $this->getModule( $name );
 167                         if ( $module ) {
 168                                 $module->setMsgBlobMtime( $lang, 1 );
 169                         }
 170                 }
 171         }
 172
 173         /**
 174          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 175          *
 176          * Available filters are:
 177          *
 178          *    - minify-js \see JavaScriptMinifier::minify
 179          *    - minify-css \see CSSMin::minify
 180          *
 181          * If $data is empty, only contains whitespace or the filter was unknown,
 182          * $data is returned unmodified.
 183          *
 184          * @param string $filter Name of filter to run
 185          * @param string $data Text to filter, such as JavaScript or CSS text
 186          * @param array $options Keys:
 187          *  - (bool) cache: Whether to allow caching this data. Default: true.
 188          * @return string Filtered data, or a comment containing an error message
 189          */
 190         public static function filter( $filter, $data, Array $options = array() ) {
 191                 if ( strpos( $data, ResourceLoader::FILTER_NOMIN ) !== false ) {
 192                         return $data;
 193                 }
 194
 195                 if ( isset( $options['cache'] ) && $options['cache'] === false ) {
 196                         return self::applyFilter( $filter, $data );
 197                 }
 198
 199                 $stats = RequestContext::getMain()->getStats();
 200                 $cache = ObjectCache::newAccelerator( CACHE_ANYTHING );
 201
 202                 $key = $cache->makeGlobalKey(
 203                         'resourceloader',
 204                         'filter',
 205                         $filter,
 206                         self::$filterCacheVersion, md5( $data )
 207                 );
 208
 209                 $result = $cache->get( $key );
 210                 if ( $result === false ) {
 211                         $stats->increment( "resourceloader_cache.$filter.miss" );
 212                         $result = self::applyFilter( $filter, $data );
 213                         $cache->set( $key, $result, 24 * 3600 );
 214                 } else {
 215                         $stats->increment( "resourceloader_cache.$filter.hit" );
 216                 }
 217                 if ( $result === null ) {
 218                         // Cached failure
 219                         $result = $data;
 220                 }
 221
 222                 return $result;
 223         }
 224
 225         private static function applyFilter( $filter, $data ) {
 226                 $data = trim( $data );
 227                 if ( $data ) {
 228                         try {
 229                                 $data = ( $filter === 'minify-css' )
 230                                         ? CSSMin::minify( $data )
 231                                         : JavaScriptMinifier::minify( $data );
 232                         } catch ( Exception $e ) {
 233                                 MWExceptionHandler::logException( $e );
 234                                 return null;
 235                         }
 236                 }
 237                 return $data;
 238         }
 239
 240         /* Methods */
 241
 242         /**
 243          * Register core modules and runs registration hooks.
 244          * @param Config|null $config
 245          */
 246         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 247                 global $IP;
 248
 249                 if ( !$logger ) {
 250                         $logger = new NullLogger();
 251                 }
 252                 $this->setLogger( $logger );
 253
 254                 if ( !$config ) {
 255                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 256                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 257                 }
 258                 $this->config = $config;
 259
 260                 // Add 'local' source first
 261                 $this->addSource( 'local', wfScript( 'load' ) );
 262
 263                 // Add other sources
 264                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 265
 266                 // Register core modules
 267                 $this->register( include "$IP/resources/Resources.php" );
 268                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 269                 // Register extension modules
 270                 $this->register( $config->get( 'ResourceModules' ) );
 271                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 272
 273                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 274                         $this->registerTestModules();
 275                 }
 276
 277                 $this->setMessageBlobStore( new MessageBlobStore() );
 278         }
 279
 280         /**
 281          * @return Config
 282          */
 283         public function getConfig() {
 284                 return $this->config;
 285         }
 286
 287         public function setLogger( LoggerInterface $logger ) {
 288                 $this->logger = $logger;
 289         }
 290
 291         /**
 292          * @since 1.26
 293          * @return MessageBlobStore
 294          */
 295         public function getMessageBlobStore() {
 296                 return $this->blobStore;
 297         }
 298
 299         /**
 300          * @since 1.25
 301          * @param MessageBlobStore $blobStore
 302          */
 303         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 304                 $this->blobStore = $blobStore;
 305         }
 306
 307         /**
 308          * Register a module with the ResourceLoader system.
 309          *
 310          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 311          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 312          *   this may also be a ResourceLoaderModule object. Optional when using
 313          *   multiple-registration calling style.
 314          * @throws MWException If a duplicate module registration is attempted
 315          * @throws MWException If a module name contains illegal characters (pipes or commas)
 316          * @throws MWException If something other than a ResourceLoaderModule is being registered
 317          * @return bool False if there were any errors, in which case one or more modules were
 318          *   not registered
 319          */
 320         public function register( $name, $info = null ) {
 321
 322                 // Allow multiple modules to be registered in one call
 323                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 324                 foreach ( $registrations as $name => $info ) {
 325                         // Warn on duplicate registrations
 326                         if ( isset( $this->moduleInfos[$name] ) ) {
 327                                 // A module has already been registered by this name
 328                                 if ( $this->moduleInfos[$name] === $info ) {
 329                                         $this->logger->warning(
 330                                                 'ResourceLoader duplicate registration warning. ' .
 331                                                 'Another module has already been registered as ' . $name
 332                                         );
 333                                 }
 334                         }
 335
 336                         // Check $name for validity
 337                         if ( !self::isValidModuleName( $name ) ) {
 338                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 339                                         . "see ResourceLoader::isValidModuleName()" );
 340                         }
 341
 342                         // Attach module
 343                         if ( $info instanceof ResourceLoaderModule ) {
 344                                 $this->moduleInfos[$name] = array( 'object' => $info );
 345                                 $info->setName( $name );
 346                                 $this->modules[$name] = $info;
 347                         } elseif ( is_array( $info ) ) {
 348                                 // New calling convention
 349                                 $this->moduleInfos[$name] = $info;
 350                         } else {
 351                                 throw new MWException(
 352                                         'ResourceLoader module info type error for module \'' . $name .
 353                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 354                                 );
 355                         }
 356
 357                         // Last-minute changes
 358
 359                         // Apply custom skin-defined styles to existing modules.
 360                         if ( $this->isFileModule( $name ) ) {
 361                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 362                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 363                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 364                                                 continue;
 365                                         }
 366
 367                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 368                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 369                                         if ( isset( $skinStyles[$name] ) ) {
 370                                                 $paths = (array)$skinStyles[$name];
 371                                                 $styleFiles = array();
 372                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 373                                                 $paths = (array)$skinStyles['+' . $name];
 374                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 375                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 376                                                         array();
 377                                         } else {
 378                                                 continue;
 379                                         }
 380
 381                                         // Add new file paths, remapping them to refer to our directories and not use settings
 382                                         // from the module we're modifying, which come from the base definition.
 383                                         list( $localBasePath, $remoteBasePath ) =
 384                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 385
 386                                         foreach ( $paths as $path ) {
 387                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 388                                         }
 389
 390                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 391                                 }
 392                         }
 393                 }
 394
 395         }
 396
 397         /**
 398          */
 399         public function registerTestModules() {
 400                 global $IP;
 401
 402                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 403                         throw new MWException( 'Attempt to register JavaScript test modules '
 404                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 405                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 406                 }
 407
 408                 // Get core test suites
 409                 $testModules = array();
 410                 $testModules['qunit'] = array();
 411                 // Get other test suites (e.g. from extensions)
 412                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 413
 414                 // Add the testrunner (which configures QUnit) to the dependencies.
 415                 // Since it must be ready before any of the test suites are executed.
 416                 foreach ( $testModules['qunit'] as &$module ) {
 417                         // Make sure all test modules are top-loading so that when QUnit starts
 418                         // on document-ready, it will run once and finish. If some tests arrive
 419                         // later (possibly after QUnit has already finished) they will be ignored.
 420                         $module['position'] = 'top';
 421                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 422                 }
 423
 424                 $testModules['qunit'] =
 425                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 426
 427                 foreach ( $testModules as $id => $names ) {
 428                         // Register test modules
 429                         $this->register( $testModules[$id] );
 430
 431                         // Keep track of their names so that they can be loaded together
 432                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 433                 }
 434
 435         }
 436
 437         /**
 438          * Add a foreign source of modules.
 439          *
 440          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 441          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 442          *  backwards-compatibility.
 443          * @throws MWException
 444          */
 445         public function addSource( $id, $loadUrl = null ) {
 446                 // Allow multiple sources to be registered in one call
 447                 if ( is_array( $id ) ) {
 448                         foreach ( $id as $key => $value ) {
 449                                 $this->addSource( $key, $value );
 450                         }
 451                         return;
 452                 }
 453
 454                 // Disallow duplicates
 455                 if ( isset( $this->sources[$id] ) ) {
 456                         throw new MWException(
 457                                 'ResourceLoader duplicate source addition error. ' .
 458                                 'Another source has already been registered as ' . $id
 459                         );
 460                 }
 461
 462                 // Pre 1.24 backwards-compatibility
 463                 if ( is_array( $loadUrl ) ) {
 464                         if ( !isset( $loadUrl['loadScript'] ) ) {
 465                                 throw new MWException(
 466                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 467                                 );
 468                         }
 469
 470                         $loadUrl = $loadUrl['loadScript'];
 471                 }
 472
 473                 $this->sources[$id] = $loadUrl;
 474         }
 475
 476         /**
 477          * Get a list of module names.
 478          *
 479          * @return array List of module names
 480          */
 481         public function getModuleNames() {
 482                 return array_keys( $this->moduleInfos );
 483         }
 484
 485         /**
 486          * Get a list of test module names for one (or all) frameworks.
 487          *
 488          * If the given framework id is unknkown, or if the in-object variable is not an array,
 489          * then it will return an empty array.
 490          *
 491          * @param string $framework Get only the test module names for one
 492          *   particular framework (optional)
 493          * @return array
 494          */
 495         public function getTestModuleNames( $framework = 'all' ) {
 496                 /** @todo api siteinfo prop testmodulenames modulenames */
 497                 if ( $framework == 'all' ) {
 498                         return $this->testModuleNames;
 499                 } elseif ( isset( $this->testModuleNames[$framework] )
 500                         && is_array( $this->testModuleNames[$framework] )
 501                 ) {
 502                         return $this->testModuleNames[$framework];
 503                 } else {
 504                         return array();
 505                 }
 506         }
 507
 508         /**
 509          * Check whether a ResourceLoader module is registered
 510          *
 511          * @since 1.25
 512          * @param string $name
 513          * @return bool
 514          */
 515         public function isModuleRegistered( $name ) {
 516                 return isset( $this->moduleInfos[$name] );
 517         }
 518
 519         /**
 520          * Get the ResourceLoaderModule object for a given module name.
 521          *
 522          * If an array of module parameters exists but a ResourceLoaderModule object has not
 523          * yet been instantiated, this method will instantiate and cache that object such that
 524          * subsequent calls simply return the same object.
 525          *
 526          * @param string $name Module name
 527          * @return ResourceLoaderModule|null If module has been registered, return a
 528          *  ResourceLoaderModule instance. Otherwise, return null.
 529          */
 530         public function getModule( $name ) {
 531                 if ( !isset( $this->modules[$name] ) ) {
 532                         if ( !isset( $this->moduleInfos[$name] ) ) {
 533                                 // No such module
 534                                 return null;
 535                         }
 536                         // Construct the requested object
 537                         $info = $this->moduleInfos[$name];
 538                         /** @var ResourceLoaderModule $object */
 539                         if ( isset( $info['object'] ) ) {
 540                                 // Object given in info array
 541                                 $object = $info['object'];
 542                         } else {
 543                                 if ( !isset( $info['class'] ) ) {
 544                                         $class = 'ResourceLoaderFileModule';
 545                                 } else {
 546                                         $class = $info['class'];
 547                                 }
 548                                 /** @var ResourceLoaderModule $object */
 549                                 $object = new $class( $info );
 550                                 $object->setConfig( $this->getConfig() );
 551                         }
 552                         $object->setName( $name );
 553                         $this->modules[$name] = $object;
 554                 }
 555
 556                 return $this->modules[$name];
 557         }
 558
 559         /**
 560          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 561          *
 562          * @param string $name Module name
 563          * @return bool
 564          */
 565         protected function isFileModule( $name ) {
 566                 if ( !isset( $this->moduleInfos[$name] ) ) {
 567                         return false;
 568                 }
 569                 $info = $this->moduleInfos[$name];
 570                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 571                         return false;
 572                 }
 573                 return true;
 574         }
 575
 576         /**
 577          * Get the list of sources.
 578          *
 579          * @return array Like array( id => load.php url, .. )
 580          */
 581         public function getSources() {
 582                 return $this->sources;
 583         }
 584
 585         /**
 586          * Get the URL to the load.php endpoint for the given
 587          * ResourceLoader source
 588          *
 589          * @since 1.24
 590          * @param string $source
 591          * @throws MWException On an invalid $source name
 592          * @return string
 593          */
 594         public function getLoadScript( $source ) {
 595                 if ( !isset( $this->sources[$source] ) ) {
 596                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 597                 }
 598                 return $this->sources[$source];
 599         }
 600
 601         /**
 602          * @since 1.26
 603          * @param string $value
 604          * @return string Hash
 605          */
 606         public static function makeHash( $value ) {
 607                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 608                 // The first 8 chars of a base64 encoded digest represent the same binary as
 609                 // the first 12 chars of a hex encoded digest.
 610                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 611         }
 612
 613         /**
 614          * Helper method to get and combine versions of multiple modules.
 615          *
 616          * @since 1.26
 617          * @param ResourceLoaderContext $context
 618          * @param array $modules List of ResourceLoaderModule objects
 619          * @return string Hash
 620          */
 621         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 622                 if ( !$modules ) {
 623                         return '';
 624                 }
 625                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 626                 // http://php.net/functions.anonymous
 627                 $rl = $this;
 628                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 629                         return $rl->getModule( $module )->getVersionHash( $context );
 630                 }, $modules );
 631                 return self::makeHash( implode( $hashes ) );
 632         }
 633
 634         /**
 635          * Output a response to a load request, including the content-type header.
 636          *
 637          * @param ResourceLoaderContext $context Context in which a response should be formed
 638          */
 639         public function respond( ResourceLoaderContext $context ) {
 640                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 641                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 642                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 643                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 644                 // the whole thing in our own output buffer to be sure the active buffer
 645                 // doesn't use ob_gzhandler.
 646                 // See http://bugs.php.net/bug.php?id=36514
 647                 ob_start();
 648
 649                 // Find out which modules are missing and instantiate the others
 650                 $modules = array();
 651                 $missing = array();
 652                 foreach ( $context->getModules() as $name ) {
 653                         $module = $this->getModule( $name );
 654                         if ( $module ) {
 655                                 // Do not allow private modules to be loaded from the web.
 656                                 // This is a security issue, see bug 34907.
 657                                 if ( $module->getGroup() === 'private' ) {
 658                                         $this->logger->debug( "Request for private module '$name' denied" );
 659                                         $this->errors[] = "Cannot show private module \"$name\"";
 660                                         continue;
 661                                 }
 662                                 $modules[$name] = $module;
 663                         } else {
 664                                 $missing[] = $name;
 665                         }
 666                 }
 667
 668                 try {
 669                         // Preload for getCombinedVersion()
 670                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 671                 } catch ( Exception $e ) {
 672                         MWExceptionHandler::logException( $e );
 673                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 674                                 'exception' => $e
 675                         ) );
 676                         $this->errors[] = self::formatExceptionNoComment( $e );
 677                 }
 678
 679                 // Combine versions to propagate cache invalidation
 680                 $versionHash = '';
 681                 try {
 682                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 683                 } catch ( Exception $e ) {
 684                         MWExceptionHandler::logException( $e );
 685                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 686                                 'exception' => $e
 687                         ) );
 688                         $this->errors[] = self::formatExceptionNoComment( $e );
 689                 }
 690
 691                 // See RFC 2616 § 3.11 Entity Tags
 692                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 693                 $etag = 'W/"' . $versionHash . '"';
 694
 695                 // Try the client-side cache first
 696                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 697                         return; // output handled (buffers cleared)
 698                 }
 699
 700                 // Use file cache if enabled and available...
 701                 if ( $this->config->get( 'UseFileCache' ) ) {
 702                         $fileCache = ResourceFileCache::newFromContext( $context );
 703                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 704                                 return; // output handled
 705                         }
 706                 }
 707
 708                 // Generate a response
 709                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 710
 711                 // Capture any PHP warnings from the output buffer and append them to the
 712                 // error list if we're in debug mode.
 713                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 714                         $this->errors[] = $warnings;
 715                 }
 716
 717                 // Save response to file cache unless there are errors
 718                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 719                         // Cache single modules and images...and other requests if there are enough hits
 720                         if ( ResourceFileCache::useFileCache( $context ) ) {
 721                                 if ( $fileCache->isCacheWorthy() ) {
 722                                         $fileCache->saveText( $response );
 723                                 } else {
 724                                         $fileCache->incrMissesRecent( $context->getRequest() );
 725                                 }
 726                         }
 727                 }
 728
 729                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 730
 731                 // Remove the output buffer and output the response
 732                 ob_end_clean();
 733
 734                 if ( $context->getImageObj() && $this->errors ) {
 735                         // We can't show both the error messages and the response when it's an image.
 736                         $response = implode( "\n\n", $this->errors );
 737                 } elseif ( $this->errors ) {
 738                         $errorText = implode( "\n\n", $this->errors );
 739                         $errorResponse = self::makeComment( $errorText );
 740                         if ( $context->shouldIncludeScripts() ) {
 741                                 $errorResponse .= 'if (window.console && console.error) {'
 742                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 743                                         . "}\n";
 744                         }
 745
 746                         // Prepend error info to the response
 747                         $response = $errorResponse . $response;
 748                 }
 749
 750                 $this->errors = array();
 751                 echo $response;
 752
 753         }
 754
 755         /**
 756          * Send main response headers to the client.
 757          *
 758          * Deals with Content-Type, CORS (for stylesheets), and caching.
 759          *
 760          * @param ResourceLoaderContext $context
 761          * @param string $etag ETag header value
 762          * @param bool $errors Whether there are errors in the response
 763          * @return void
 764          */
 765         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 766                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 767                 // If a version wasn't specified we need a shorter expiry time for updates
 768                 // to propagate to clients quickly
 769                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 770                 if ( is_null( $context->getVersion() ) || $errors ) {
 771                         $maxage = $rlMaxage['unversioned']['client'];
 772                         $smaxage = $rlMaxage['unversioned']['server'];
 773                 // If a version was specified we can use a longer expiry time since changing
 774                 // version numbers causes cache misses
 775                 } else {
 776                         $maxage = $rlMaxage['versioned']['client'];
 777                         $smaxage = $rlMaxage['versioned']['server'];
 778                 }
 779                 if ( $context->getImageObj() ) {
 780                         // Output different headers if we're outputting textual errors.
 781                         if ( $errors ) {
 782                                 header( 'Content-Type: text/plain; charset=utf-8' );
 783                         } else {
 784                                 $context->getImageObj()->sendResponseHeaders( $context );
 785                         }
 786                 } elseif ( $context->getOnly() === 'styles' ) {
 787                         header( 'Content-Type: text/css; charset=utf-8' );
 788                         header( 'Access-Control-Allow-Origin: *' );
 789                 } else {
 790                         header( 'Content-Type: text/javascript; charset=utf-8' );
 791                 }
 792                 // See RFC 2616 § 14.19 ETag
 793                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 794                 header( 'ETag: ' . $etag );
 795                 if ( $context->getDebug() ) {
 796                         // Do not cache debug responses
 797                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 798                         header( 'Pragma: no-cache' );
 799                 } else {
 800                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 801                         $exp = min( $maxage, $smaxage );
 802                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 803                 }
 804
 805                 // Send the current time expressed as fractional seconds since epoch,
 806                 // with microsecond precision. This helps distinguish hits from misses
 807                 // in edge caches.
 808                 header( 'MediaWiki-Timestamp: ' . microtime( true ) );
 809         }
 810
 811         /**
 812          * Respond with HTTP 304 Not Modified if appropiate.
 813          *
 814          * If there's an If-None-Match header, respond with a 304 appropriately
 815          * and clear out the output buffer. If the client cache is too old then do nothing.
 816          *
 817          * @param ResourceLoaderContext $context
 818          * @param string $etag ETag header value
 819          * @return bool True if HTTP 304 was sent and output handled
 820          */
 821         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 822                 // See RFC 2616 § 14.26 If-None-Match
 823                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 824                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 825                 // Never send 304s in debug mode
 826                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 827                         // There's another bug in ob_gzhandler (see also the comment at
 828                         // the top of this function) that causes it to gzip even empty
 829                         // responses, meaning it's impossible to produce a truly empty
 830                         // response (because the gzip header is always there). This is
 831                         // a problem because 304 responses have to be completely empty
 832                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 833                         // See also http://bugs.php.net/bug.php?id=51579
 834                         // To work around this, we tear down all output buffering before
 835                         // sending the 304.
 836                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 837
 838                         HttpStatus::header( 304 );
 839
 840                         $this->sendResponseHeaders( $context, $etag, false );
 841                         return true;
 842                 }
 843                 return false;
 844         }
 845
 846         /**
 847          * Send out code for a response from file cache if possible.
 848          *
 849          * @param ResourceFileCache $fileCache Cache object for this request URL
 850          * @param ResourceLoaderContext $context Context in which to generate a response
 851          * @param string $etag ETag header value
 852          * @return bool If this found a cache file and handled the response
 853          */
 854         protected function tryRespondFromFileCache(
 855                 ResourceFileCache $fileCache,
 856                 ResourceLoaderContext $context,
 857                 $etag
 858         ) {
 859                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 860                 // Buffer output to catch warnings.
 861                 ob_start();
 862                 // Get the maximum age the cache can be
 863                 $maxage = is_null( $context->getVersion() )
 864                         ? $rlMaxage['unversioned']['server']
 865                         : $rlMaxage['versioned']['server'];
 866                 // Minimum timestamp the cache file must have
 867                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 868                 if ( !$good ) {
 869                         try { // RL always hits the DB on file cache miss...
 870                                 wfGetDB( DB_SLAVE );
 871                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 872                                 $good = $fileCache->isCacheGood(); // cache existence check
 873                         }
 874                 }
 875                 if ( $good ) {
 876                         $ts = $fileCache->cacheTimestamp();
 877                         // Send content type and cache headers
 878                         $this->sendResponseHeaders( $context, $etag, false );
 879                         $response = $fileCache->fetchText();
 880                         // Capture any PHP warnings from the output buffer and append them to the
 881                         // response in a comment if we're in debug mode.
 882                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 883                                 $response = self::makeComment( $warnings ) . $response;
 884                         }
 885                         // Remove the output buffer and output the response
 886                         ob_end_clean();
 887                         echo $response . "\n/* Cached {$ts} */";
 888                         return true; // cache hit
 889                 }
 890                 // Clear buffer
 891                 ob_end_clean();
 892
 893                 return false; // cache miss
 894         }
 895
 896         /**
 897          * Generate a CSS or JS comment block.
 898          *
 899          * Only use this for public data, not error message details.
 900          *
 901          * @param string $text
 902          * @return string
 903          */
 904         public static function makeComment( $text ) {
 905                 $encText = str_replace( '*/', '* /', $text );
 906                 return "/*\n$encText\n*/\n";
 907         }
 908
 909         /**
 910          * Handle exception display.
 911          *
 912          * @param Exception $e Exception to be shown to the user
 913          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 914          */
 915         public static function formatException( $e ) {
 916                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 917         }
 918
 919         /**
 920          * Handle exception display.
 921          *
 922          * @since 1.25
 923          * @param Exception $e Exception to be shown to the user
 924          * @return string Sanitized text that can be returned to the user
 925          */
 926         protected static function formatExceptionNoComment( $e ) {
 927                 global $wgShowExceptionDetails;
 928
 929                 if ( !$wgShowExceptionDetails ) {
 930                         return MWExceptionHandler::getPublicLogMessage( $e );
 931                 }
 932
 933                 return MWExceptionHandler::getLogMessage( $e );
 934         }
 935
 936         /**
 937          * Generate code for a response.
 938          *
 939          * @param ResourceLoaderContext $context Context in which to generate a response
 940          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 941          * @param string[] $missing List of requested module names that are unregistered (optional)
 942          * @return string Response data
 943          */
 944         public function makeModuleResponse( ResourceLoaderContext $context,
 945                 array $modules, array $missing = array()
 946         ) {
 947                 $out = '';
 948                 $states = array();
 949
 950                 if ( !count( $modules ) && !count( $missing ) ) {
 951                         return <<<MESSAGE
 952 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 953    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 954    no modules were requested. Max made me put this here. */
 955 MESSAGE;
 956                 }
 957
 958                 $image = $context->getImageObj();
 959                 if ( $image ) {
 960                         $data = $image->getImageData( $context );
 961                         if ( $data === false ) {
 962                                 $data = '';
 963                                 $this->errors[] = 'Image generation failed';
 964                         }
 965                         return $data;
 966                 }
 967
 968                 // Pre-fetch blobs
 969                 if ( $context->shouldIncludeMessages() ) {
 970                         try {
 971                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 972                         } catch ( Exception $e ) {
 973                                 MWExceptionHandler::logException( $e );
 974                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 975                                         'exception' => $e
 976                                 ) );
 977                                 $this->errors[] = self::formatExceptionNoComment( $e );
 978                         }
 979                 }
 980
 981                 foreach ( $missing as $name ) {
 982                         $states[$name] = 'missing';
 983                 }
 984
 985                 // Generate output
 986                 $isRaw = false;
 987
 988                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
 989
 990                 foreach ( $modules as $name => $module ) {
 991                         try {
 992                                 $content = $module->getModuleContent( $context );
 993                                 $strContent = '';
 994
 995                                 // Append output
 996                                 switch ( $context->getOnly() ) {
 997                                         case 'scripts':
 998                                                 $scripts = $content['scripts'];
 999                                                 if ( is_string( $scripts ) ) {
1000                                                         // Load scripts raw...
1001                                                         $strContent = $scripts;
1002                                                 } elseif ( is_array( $scripts ) ) {
1003                                                         // ...except when $scripts is an array of URLs
1004                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
1005                                                 }
1006                                                 break;
1007                                         case 'styles':
1008                                                 $styles = $content['styles'];
1009                                                 // We no longer seperate into media, they are all combined now with
1010                                                 // custom media type groups into @media .. {} sections as part of the css string.
1011                                                 // Module returns either an empty array or a numerical array with css strings.
1012                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1013                                                 break;
1014                                         default:
1015                                                 $strContent = self::makeLoaderImplementScript(
1016                                                         $name,
1017                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1018                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1019                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1020                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1021                                                 );
1022                                                 break;
1023                                 }
1024
1025                                 if ( !$context->getDebug() ) {
1026                                         $strContent = self::filter( $filter, $strContent );
1027                                 }
1028
1029                                 $out .= $strContent;
1030
1031                         } catch ( Exception $e ) {
1032                                 MWExceptionHandler::logException( $e );
1033                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1034                                         'exception' => $e
1035                                 ) );
1036                                 $this->errors[] = self::formatExceptionNoComment( $e );
1037
1038                                 // Respond to client with error-state instead of module implementation
1039                                 $states[$name] = 'error';
1040                                 unset( $modules[$name] );
1041                         }
1042                         $isRaw |= $module->isRaw();
1043                 }
1044
1045                 // Update module states
1046                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1047                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1048                                 // Set the state of modules loaded as only scripts to ready as
1049                                 // they don't have an mw.loader.implement wrapper that sets the state
1050                                 foreach ( $modules as $name => $module ) {
1051                                         $states[$name] = 'ready';
1052                                 }
1053                         }
1054
1055                         // Set the state of modules we didn't respond to with mw.loader.implement
1056                         if ( count( $states ) ) {
1057                                 $stateScript = self::makeLoaderStateScript( $states );
1058                                 if ( !$context->getDebug() ) {
1059                                         $stateScript = self::filter( 'minify-js', $stateScript );
1060                                 }
1061                                 $out .= $stateScript;
1062                         }
1063                 } else {
1064                         if ( count( $states ) ) {
1065                                 $this->errors[] = 'Problematic modules: ' .
1066                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1067                         }
1068                 }
1069
1070                 return $out;
1071         }
1072
1073         /* Static Methods */
1074
1075         /**
1076          * Return JS code that calls mw.loader.implement with given module properties.
1077          *
1078          * @param string $name Module name
1079          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1080          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1081          *   to CSS files keyed by media type
1082          * @param mixed $messages List of messages associated with this module. May either be an
1083          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1084          *   the same data, wrapped in an XmlJsCode object.
1085          * @param array $templates Keys are name of templates and values are the source of
1086          *   the template.
1087          * @throws MWException
1088          * @return string
1089          */
1090         public static function makeLoaderImplementScript(
1091                 $name, $scripts, $styles, $messages, $templates
1092         ) {
1093                 if ( is_string( $scripts ) ) {
1094                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1095                         // Transportation as string instructs mw.loader.implement to use globalEval.
1096                         if ( $name === 'site' || $name === 'user' ) {
1097                                 // Minify manually because the general makeModuleResponse() minification won't be
1098                                 // effective here due to the script being a string instead of a function. (T107377)
1099                                 if ( !ResourceLoader::inDebugMode() ) {
1100                                         $scripts = self::filter( 'minify-js', $scripts );
1101                                 }
1102                         } else {
1103                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1104                         }
1105                 } elseif ( !is_array( $scripts ) ) {
1106                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1107                 }
1108                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1109                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1110                 // of "{}". Force them to objects.
1111                 $module = array(
1112                         $name,
1113                         $scripts,
1114                         (object)$styles,
1115                         (object)$messages,
1116                         (object)$templates,
1117                 );
1118                 self::trimArray( $module );
1119
1120                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1121         }
1122
1123         /**
1124          * Returns JS code which, when called, will register a given list of messages.
1125          *
1126          * @param mixed $messages Either an associative array mapping message key to value, or a
1127          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1128          * @return string
1129          */
1130         public static function makeMessageSetScript( $messages ) {
1131                 return Xml::encodeJsCall(
1132                         'mw.messages.set',
1133                         array( (object)$messages ),
1134                         ResourceLoader::inDebugMode()
1135                 );
1136         }
1137
1138         /**
1139          * Combines an associative array mapping media type to CSS into a
1140          * single stylesheet with "@media" blocks.
1141          *
1142          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1143          * @return array
1144          */
1145         public static function makeCombinedStyles( array $stylePairs ) {
1146                 $out = array();
1147                 foreach ( $stylePairs as $media => $styles ) {
1148                         // ResourceLoaderFileModule::getStyle can return the styles
1149                         // as a string or an array of strings. This is to allow separation in
1150                         // the front-end.
1151                         $styles = (array)$styles;
1152                         foreach ( $styles as $style ) {
1153                                 $style = trim( $style );
1154                                 // Don't output an empty "@media print { }" block (bug 40498)
1155                                 if ( $style !== '' ) {
1156                                         // Transform the media type based on request params and config
1157                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1158                                         $media = OutputPage::transformCssMedia( $media );
1159
1160                                         if ( $media === '' || $media == 'all' ) {
1161                                                 $out[] = $style;
1162                                         } elseif ( is_string( $media ) ) {
1163                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1164                                         }
1165                                         // else: skip
1166                                 }
1167                         }
1168                 }
1169                 return $out;
1170         }
1171
1172         /**
1173          * Returns a JS call to mw.loader.state, which sets the state of a
1174          * module or modules to a given value. Has two calling conventions:
1175          *
1176          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1177          *         Set the state of a single module called $name to $state
1178          *
1179          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1180          *         Set the state of modules with the given names to the given states
1181          *
1182          * @param string $name
1183          * @param string $state
1184          * @return string
1185          */
1186         public static function makeLoaderStateScript( $name, $state = null ) {
1187                 if ( is_array( $name ) ) {
1188                         return Xml::encodeJsCall(
1189                                 'mw.loader.state',
1190                                 array( $name ),
1191                                 ResourceLoader::inDebugMode()
1192                         );
1193                 } else {
1194                         return Xml::encodeJsCall(
1195                                 'mw.loader.state',
1196                                 array( $name, $state ),
1197                                 ResourceLoader::inDebugMode()
1198                         );
1199                 }
1200         }
1201
1202         /**
1203          * Returns JS code which calls the script given by $script. The script will
1204          * be called with local variables name, version, dependencies and group,
1205          * which will have values corresponding to $name, $version, $dependencies
1206          * and $group as supplied.
1207          *
1208          * @param string $name Module name
1209          * @param string $version Module version hash
1210          * @param array $dependencies List of module names on which this module depends
1211          * @param string $group Group which the module is in.
1212          * @param string $source Source of the module, or 'local' if not foreign.
1213          * @param string $script JavaScript code
1214          * @return string
1215          */
1216         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1217                 $group, $source, $script
1218         ) {
1219                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1220                 return Xml::encodeJsCall(
1221                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1222                         array( $name, $version, $dependencies, $group, $source ),
1223                         ResourceLoader::inDebugMode()
1224                 );
1225         }
1226
1227         private static function isEmptyObject( stdClass $obj ) {
1228                 foreach ( $obj as $key => $value ) {
1229                         return false;
1230                 }
1231                 return true;
1232         }
1233
1234         /**
1235          * Remove empty values from the end of an array.
1236          *
1237          * Values considered empty:
1238          *
1239          * - null
1240          * - array()
1241          * - new XmlJsCode( '{}' )
1242          * - new stdClass() // (object) array()
1243          *
1244          * @param Array $array
1245          */
1246         private static function trimArray( Array &$array ) {
1247                 $i = count( $array );
1248                 while ( $i-- ) {
1249                         if ( $array[$i] === null
1250                                 || $array[$i] === array()
1251                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1252                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1253                         ) {
1254                                 unset( $array[$i] );
1255                         } else {
1256                                 break;
1257                         }
1258                 }
1259         }
1260
1261         /**
1262          * Returns JS code which calls mw.loader.register with the given
1263          * parameters. Has three calling conventions:
1264          *
1265          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1266          *        $dependencies, $group, $source, $skip
1267          *     ):
1268          *        Register a single module.
1269          *
1270          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1271          *        Register modules with the given names.
1272          *
1273          *   - ResourceLoader::makeLoaderRegisterScript( array(
1274          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1275          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1276          *        ...
1277          *     ) ):
1278          *        Registers modules with the given names and parameters.
1279          *
1280          * @param string $name Module name
1281          * @param string $version Module version hash
1282          * @param array $dependencies List of module names on which this module depends
1283          * @param string $group Group which the module is in
1284          * @param string $source Source of the module, or 'local' if not foreign
1285          * @param string $skip Script body of the skip function
1286          * @return string
1287          */
1288         public static function makeLoaderRegisterScript( $name, $version = null,
1289                 $dependencies = null, $group = null, $source = null, $skip = null
1290         ) {
1291                 if ( is_array( $name ) ) {
1292                         // Build module name index
1293                         $index = array();
1294                         foreach ( $name as $i => &$module ) {
1295                                 $index[$module[0]] = $i;
1296                         }
1297
1298                         // Transform dependency names into indexes when possible, they will be resolved by
1299                         // mw.loader.register on the other end
1300                         foreach ( $name as &$module ) {
1301                                 if ( isset( $module[2] ) ) {
1302                                         foreach ( $module[2] as &$dependency ) {
1303                                                 if ( isset( $index[$dependency] ) ) {
1304                                                         $dependency = $index[$dependency];
1305                                                 }
1306                                         }
1307                                 }
1308                         }
1309
1310                         array_walk( $name, array( 'self', 'trimArray' ) );
1311
1312                         return Xml::encodeJsCall(
1313                                 'mw.loader.register',
1314                                 array( $name ),
1315                                 ResourceLoader::inDebugMode()
1316                         );
1317                 } else {
1318                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1319                         self::trimArray( $registration );
1320                         return Xml::encodeJsCall(
1321                                 'mw.loader.register',
1322                                 $registration,
1323                                 ResourceLoader::inDebugMode()
1324                         );
1325                 }
1326         }
1327
1328         /**
1329          * Returns JS code which calls mw.loader.addSource() with the given
1330          * parameters. Has two calling conventions:
1331          *
1332          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1333          *       Register a single source
1334          *
1335          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1336          *       Register sources with the given IDs and properties.
1337          *
1338          * @param string $id Source ID
1339          * @param array $properties Source properties (see addSource())
1340          * @return string
1341          */
1342         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1343                 if ( is_array( $id ) ) {
1344                         return Xml::encodeJsCall(
1345                                 'mw.loader.addSource',
1346                                 array( $id ),
1347                                 ResourceLoader::inDebugMode()
1348                         );
1349                 } else {
1350                         return Xml::encodeJsCall(
1351                                 'mw.loader.addSource',
1352                                 array( $id, $properties ),
1353                                 ResourceLoader::inDebugMode()
1354                         );
1355                 }
1356         }
1357
1358         /**
1359          * Returns JS code which runs given JS code if the client-side framework is
1360          * present.
1361          *
1362          * @deprecated since 1.25; use makeInlineScript instead
1363          * @param string $script JavaScript code
1364          * @return string
1365          */
1366         public static function makeLoaderConditionalScript( $script ) {
1367                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1368                         trim( $script ) . "\n} );";
1369         }
1370
1371         /**
1372          * Construct an inline script tag with given JS code.
1373          *
1374          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1375          * only if the client has adequate support for MediaWiki JavaScript code.
1376          *
1377          * @param string $script JavaScript code
1378          * @return WrappedString HTML
1379          */
1380         public static function makeInlineScript( $script ) {
1381                 $js = self::makeLoaderConditionalScript( $script );
1382                 return new WrappedString(
1383                         Html::inlineScript( $js ),
1384                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1385                         "\n} );</script>"
1386                 );
1387         }
1388
1389         /**
1390          * Returns JS code which will set the MediaWiki configuration array to
1391          * the given value.
1392          *
1393          * @param array $configuration List of configuration values keyed by variable name
1394          * @return string
1395          */
1396         public static function makeConfigSetScript( array $configuration ) {
1397                 return Xml::encodeJsCall(
1398                         'mw.config.set',
1399                         array( $configuration ),
1400                         ResourceLoader::inDebugMode()
1401                 ) . ResourceLoader::FILTER_NOMIN;
1402         }
1403
1404         /**
1405          * Convert an array of module names to a packed query string.
1406          *
1407          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1408          * becomes 'foo.bar,baz|bar.baz,quux'
1409          * @param array $modules List of module names (strings)
1410          * @return string Packed query string
1411          */
1412         public static function makePackedModulesString( $modules ) {
1413                 $groups = array(); // array( prefix => array( suffixes ) )
1414                 foreach ( $modules as $module ) {
1415                         $pos = strrpos( $module, '.' );
1416                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1417                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1418                         $groups[$prefix][] = $suffix;
1419                 }
1420
1421                 $arr = array();
1422                 foreach ( $groups as $prefix => $suffixes ) {
1423                         $p = $prefix === '' ? '' : $prefix . '.';
1424                         $arr[] = $p . implode( ',', $suffixes );
1425                 }
1426                 $str = implode( '|', $arr );
1427                 return $str;
1428         }
1429
1430         /**
1431          * Determine whether debug mode was requested
1432          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1433          * @return bool
1434          */
1435         public static function inDebugMode() {
1436                 if ( self::$debugMode === null ) {
1437                         global $wgRequest, $wgResourceLoaderDebug;
1438                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1439                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1440                         );
1441                 }
1442                 return self::$debugMode;
1443         }
1444
1445         /**
1446          * Reset static members used for caching.
1447          *
1448          * Global state and $wgRequest are evil, but we're using it right
1449          * now and sometimes we need to be able to force ResourceLoader to
1450          * re-evaluate the context because it has changed (e.g. in the test suite).
1451          */
1452         public static function clearCache() {
1453                 self::$debugMode = null;
1454         }
1455
1456         /**
1457          * Build a load.php URL
1458          *
1459          * @since 1.24
1460          * @param string $source Name of the ResourceLoader source
1461          * @param ResourceLoaderContext $context
1462          * @param array $extraQuery
1463          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1464          */
1465         public function createLoaderURL( $source, ResourceLoaderContext $context,
1466                 $extraQuery = array()
1467         ) {
1468                 $query = self::createLoaderQuery( $context, $extraQuery );
1469                 $script = $this->getLoadScript( $source );
1470
1471                 return wfAppendQuery( $script, $query );
1472         }
1473
1474         /**
1475          * Build a load.php URL
1476          * @deprecated since 1.24 Use createLoaderURL() instead
1477          * @param array $modules Array of module names (strings)
1478          * @param string $lang Language code
1479          * @param string $skin Skin name
1480          * @param string|null $user User name. If null, the &user= parameter is omitted
1481          * @param string|null $version Versioning timestamp
1482          * @param bool $debug Whether the request should be in debug mode
1483          * @param string|null $only &only= parameter
1484          * @param bool $printable Printable mode
1485          * @param bool $handheld Handheld mode
1486          * @param array $extraQuery Extra query parameters to add
1487          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1488          */
1489         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1490                 $version = null, $debug = false, $only = null, $printable = false,
1491                 $handheld = false, $extraQuery = array()
1492         ) {
1493                 global $wgLoadScript;
1494
1495                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1496                         $only, $printable, $handheld, $extraQuery
1497                 );
1498
1499                 return wfAppendQuery( $wgLoadScript, $query );
1500         }
1501
1502         /**
1503          * Helper for createLoaderURL()
1504          *
1505          * @since 1.24
1506          * @see makeLoaderQuery
1507          * @param ResourceLoaderContext $context
1508          * @param array $extraQuery
1509          * @return array
1510          */
1511         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1512                 return self::makeLoaderQuery(
1513                         $context->getModules(),
1514                         $context->getLanguage(),
1515                         $context->getSkin(),
1516                         $context->getUser(),
1517                         $context->getVersion(),
1518                         $context->getDebug(),
1519                         $context->getOnly(),
1520                         $context->getRequest()->getBool( 'printable' ),
1521                         $context->getRequest()->getBool( 'handheld' ),
1522                         $extraQuery
1523                 );
1524         }
1525
1526         /**
1527          * Build a query array (array representation of query string) for load.php. Helper
1528          * function for makeLoaderURL().
1529          *
1530          * @param array $modules
1531          * @param string $lang
1532          * @param string $skin
1533          * @param string $user
1534          * @param string $version
1535          * @param bool $debug
1536          * @param string $only
1537          * @param bool $printable
1538          * @param bool $handheld
1539          * @param array $extraQuery
1540          *
1541          * @return array
1542          */
1543         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1544                 $version = null, $debug = false, $only = null, $printable = false,
1545                 $handheld = false, $extraQuery = array()
1546         ) {
1547                 $query = array(
1548                         'modules' => self::makePackedModulesString( $modules ),
1549                         'lang' => $lang,
1550                         'skin' => $skin,
1551                         'debug' => $debug ? 'true' : 'false',
1552                 );
1553                 if ( $user !== null ) {
1554                         $query['user'] = $user;
1555                 }
1556                 if ( $version !== null ) {
1557                         $query['version'] = $version;
1558                 }
1559                 if ( $only !== null ) {
1560                         $query['only'] = $only;
1561                 }
1562                 if ( $printable ) {
1563                         $query['printable'] = 1;
1564                 }
1565                 if ( $handheld ) {
1566                         $query['handheld'] = 1;
1567                 }
1568                 $query += $extraQuery;
1569
1570                 // Make queries uniform in order
1571                 ksort( $query );
1572                 return $query;
1573         }
1574
1575         /**
1576          * Check a module name for validity.
1577          *
1578          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1579          * at most 255 bytes.
1580          *
1581          * @param string $moduleName Module name to check
1582          * @return bool Whether $moduleName is a valid module name
1583          */
1584         public static function isValidModuleName( $moduleName ) {
1585                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1586         }
1587
1588         /**
1589          * Returns LESS compiler set up for use with MediaWiki
1590          *
1591          * @since 1.22
1592          * @since 1.27 added $extraVars parameter
1593          * @param Config $config
1594          * @param array $extraVars Associative array of extra (i.e., other than the
1595          *   globally-configured ones) that should be used for compilation.
1596          * @throws MWException
1597          * @return Less_Parser
1598          */
1599         public static function getLessCompiler( Config $config, $extraVars = array() ) {
1600                 // When called from the installer, it is possible that a required PHP extension
1601                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1602                 // exception (caught by the installer) to prevent a fatal error later on.
1603                 if ( !class_exists( 'Less_Parser' ) ) {
1604                         throw new MWException( 'MediaWiki requires the less.php parser' );
1605                 }
1606
1607                 $parser = new Less_Parser;
1608                 $parser->ModifyVars( array_merge( self::getLessVars( $config ), $extraVars ) );
1609                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1610                 $parser->SetOption( 'relativeUrls', false );
1611                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1612
1613                 return $parser;
1614         }
1615
1616         /**
1617          * Get global LESS variables.
1618          *
1619          * @param Config $config
1620          * @since 1.22
1621          * @return array Map of variable names to string CSS values.
1622          */
1623         public static function getLessVars( Config $config ) {
1624                 if ( !self::$lessVars ) {
1625                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1626                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1627                         self::$lessVars = $lessVars;
1628                 }
1629                 return self::$lessVars;
1630         }
1631 }