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::getLocalServerInstance( 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 $config [optional]
 245          * @param LoggerInterface $logger [optional]
 246          */
 247         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 248                 global $IP;
 249
 250                 if ( !$logger ) {
 251                         $logger = new NullLogger();
 252                 }
 253                 $this->setLogger( $logger );
 254
 255                 if ( !$config ) {
 256                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 257                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 258                 }
 259                 $this->config = $config;
 260
 261                 // Add 'local' source first
 262                 $this->addSource( 'local', wfScript( 'load' ) );
 263
 264                 // Add other sources
 265                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 266
 267                 // Register core modules
 268                 $this->register( include "$IP/resources/Resources.php" );
 269                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 270                 // Register extension modules
 271                 $this->register( $config->get( 'ResourceModules' ) );
 272                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 273
 274                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 275                         $this->registerTestModules();
 276                 }
 277
 278                 $this->setMessageBlobStore( new MessageBlobStore( $this ) );
 279         }
 280
 281         /**
 282          * @return Config
 283          */
 284         public function getConfig() {
 285                 return $this->config;
 286         }
 287
 288         /**
 289          * @since 1.26
 290          * @param LoggerInterface $logger
 291          */
 292         public function setLogger( LoggerInterface $logger ) {
 293                 $this->logger = $logger;
 294         }
 295
 296         /**
 297          * @since 1.27
 298          * @return LoggerInterface
 299          */
 300         public function getLogger() {
 301                 return $this->logger;
 302         }
 303
 304         /**
 305          * @since 1.26
 306          * @return MessageBlobStore
 307          */
 308         public function getMessageBlobStore() {
 309                 return $this->blobStore;
 310         }
 311
 312         /**
 313          * @since 1.25
 314          * @param MessageBlobStore $blobStore
 315          */
 316         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 317                 $this->blobStore = $blobStore;
 318         }
 319
 320         /**
 321          * Register a module with the ResourceLoader system.
 322          *
 323          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 324          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 325          *   this may also be a ResourceLoaderModule object. Optional when using
 326          *   multiple-registration calling style.
 327          * @throws MWException If a duplicate module registration is attempted
 328          * @throws MWException If a module name contains illegal characters (pipes or commas)
 329          * @throws MWException If something other than a ResourceLoaderModule is being registered
 330          * @return bool False if there were any errors, in which case one or more modules were
 331          *   not registered
 332          */
 333         public function register( $name, $info = null ) {
 334
 335                 // Allow multiple modules to be registered in one call
 336                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 337                 foreach ( $registrations as $name => $info ) {
 338                         // Warn on duplicate registrations
 339                         if ( isset( $this->moduleInfos[$name] ) ) {
 340                                 // A module has already been registered by this name
 341                                 $this->logger->warning(
 342                                         'ResourceLoader duplicate registration warning. ' .
 343                                         'Another module has already been registered as ' . $name
 344                                 );
 345                         }
 346
 347                         // Check $name for validity
 348                         if ( !self::isValidModuleName( $name ) ) {
 349                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 350                                         . "see ResourceLoader::isValidModuleName()" );
 351                         }
 352
 353                         // Attach module
 354                         if ( $info instanceof ResourceLoaderModule ) {
 355                                 $this->moduleInfos[$name] = array( 'object' => $info );
 356                                 $info->setName( $name );
 357                                 $this->modules[$name] = $info;
 358                         } elseif ( is_array( $info ) ) {
 359                                 // New calling convention
 360                                 $this->moduleInfos[$name] = $info;
 361                         } else {
 362                                 throw new MWException(
 363                                         'ResourceLoader module info type error for module \'' . $name .
 364                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 365                                 );
 366                         }
 367
 368                         // Last-minute changes
 369
 370                         // Apply custom skin-defined styles to existing modules.
 371                         if ( $this->isFileModule( $name ) ) {
 372                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 373                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 374                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 375                                                 continue;
 376                                         }
 377
 378                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 379                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 380                                         if ( isset( $skinStyles[$name] ) ) {
 381                                                 $paths = (array)$skinStyles[$name];
 382                                                 $styleFiles = array();
 383                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 384                                                 $paths = (array)$skinStyles['+' . $name];
 385                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 386                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 387                                                         array();
 388                                         } else {
 389                                                 continue;
 390                                         }
 391
 392                                         // Add new file paths, remapping them to refer to our directories and not use settings
 393                                         // from the module we're modifying, which come from the base definition.
 394                                         list( $localBasePath, $remoteBasePath ) =
 395                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 396
 397                                         foreach ( $paths as $path ) {
 398                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 399                                         }
 400
 401                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 402                                 }
 403                         }
 404                 }
 405
 406         }
 407
 408         /**
 409          */
 410         public function registerTestModules() {
 411                 global $IP;
 412
 413                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 414                         throw new MWException( 'Attempt to register JavaScript test modules '
 415                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 416                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 417                 }
 418
 419                 // Get core test suites
 420                 $testModules = array();
 421                 $testModules['qunit'] = array();
 422                 // Get other test suites (e.g. from extensions)
 423                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 424
 425                 // Add the testrunner (which configures QUnit) to the dependencies.
 426                 // Since it must be ready before any of the test suites are executed.
 427                 foreach ( $testModules['qunit'] as &$module ) {
 428                         // Make sure all test modules are top-loading so that when QUnit starts
 429                         // on document-ready, it will run once and finish. If some tests arrive
 430                         // later (possibly after QUnit has already finished) they will be ignored.
 431                         $module['position'] = 'top';
 432                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 433                 }
 434
 435                 $testModules['qunit'] =
 436                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 437
 438                 foreach ( $testModules as $id => $names ) {
 439                         // Register test modules
 440                         $this->register( $testModules[$id] );
 441
 442                         // Keep track of their names so that they can be loaded together
 443                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 444                 }
 445
 446         }
 447
 448         /**
 449          * Add a foreign source of modules.
 450          *
 451          * Source IDs are typically the same as the Wiki ID or database name (e.g. lowercase a-z).
 452          *
 453          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 454          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 455          *  backwards-compatibility.
 456          * @throws MWException
 457          */
 458         public function addSource( $id, $loadUrl = null ) {
 459                 // Allow multiple sources to be registered in one call
 460                 if ( is_array( $id ) ) {
 461                         foreach ( $id as $key => $value ) {
 462                                 $this->addSource( $key, $value );
 463                         }
 464                         return;
 465                 }
 466
 467                 // Disallow duplicates
 468                 if ( isset( $this->sources[$id] ) ) {
 469                         throw new MWException(
 470                                 'ResourceLoader duplicate source addition error. ' .
 471                                 'Another source has already been registered as ' . $id
 472                         );
 473                 }
 474
 475                 // Pre 1.24 backwards-compatibility
 476                 if ( is_array( $loadUrl ) ) {
 477                         if ( !isset( $loadUrl['loadScript'] ) ) {
 478                                 throw new MWException(
 479                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 480                                 );
 481                         }
 482
 483                         $loadUrl = $loadUrl['loadScript'];
 484                 }
 485
 486                 $this->sources[$id] = $loadUrl;
 487         }
 488
 489         /**
 490          * Get a list of module names.
 491          *
 492          * @return array List of module names
 493          */
 494         public function getModuleNames() {
 495                 return array_keys( $this->moduleInfos );
 496         }
 497
 498         /**
 499          * Get a list of test module names for one (or all) frameworks.
 500          *
 501          * If the given framework id is unknkown, or if the in-object variable is not an array,
 502          * then it will return an empty array.
 503          *
 504          * @param string $framework Get only the test module names for one
 505          *   particular framework (optional)
 506          * @return array
 507          */
 508         public function getTestModuleNames( $framework = 'all' ) {
 509                 /** @todo api siteinfo prop testmodulenames modulenames */
 510                 if ( $framework == 'all' ) {
 511                         return $this->testModuleNames;
 512                 } elseif ( isset( $this->testModuleNames[$framework] )
 513                         && is_array( $this->testModuleNames[$framework] )
 514                 ) {
 515                         return $this->testModuleNames[$framework];
 516                 } else {
 517                         return array();
 518                 }
 519         }
 520
 521         /**
 522          * Check whether a ResourceLoader module is registered
 523          *
 524          * @since 1.25
 525          * @param string $name
 526          * @return bool
 527          */
 528         public function isModuleRegistered( $name ) {
 529                 return isset( $this->moduleInfos[$name] );
 530         }
 531
 532         /**
 533          * Get the ResourceLoaderModule object for a given module name.
 534          *
 535          * If an array of module parameters exists but a ResourceLoaderModule object has not
 536          * yet been instantiated, this method will instantiate and cache that object such that
 537          * subsequent calls simply return the same object.
 538          *
 539          * @param string $name Module name
 540          * @return ResourceLoaderModule|null If module has been registered, return a
 541          *  ResourceLoaderModule instance. Otherwise, return null.
 542          */
 543         public function getModule( $name ) {
 544                 if ( !isset( $this->modules[$name] ) ) {
 545                         if ( !isset( $this->moduleInfos[$name] ) ) {
 546                                 // No such module
 547                                 return null;
 548                         }
 549                         // Construct the requested object
 550                         $info = $this->moduleInfos[$name];
 551                         /** @var ResourceLoaderModule $object */
 552                         if ( isset( $info['object'] ) ) {
 553                                 // Object given in info array
 554                                 $object = $info['object'];
 555                         } else {
 556                                 if ( !isset( $info['class'] ) ) {
 557                                         $class = 'ResourceLoaderFileModule';
 558                                 } else {
 559                                         $class = $info['class'];
 560                                 }
 561                                 /** @var ResourceLoaderModule $object */
 562                                 $object = new $class( $info );
 563                                 $object->setConfig( $this->getConfig() );
 564                         }
 565                         $object->setName( $name );
 566                         $this->modules[$name] = $object;
 567                 }
 568
 569                 return $this->modules[$name];
 570         }
 571
 572         /**
 573          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 574          *
 575          * @param string $name Module name
 576          * @return bool
 577          */
 578         protected function isFileModule( $name ) {
 579                 if ( !isset( $this->moduleInfos[$name] ) ) {
 580                         return false;
 581                 }
 582                 $info = $this->moduleInfos[$name];
 583                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 584                         return false;
 585                 }
 586                 return true;
 587         }
 588
 589         /**
 590          * Get the list of sources.
 591          *
 592          * @return array Like array( id => load.php url, .. )
 593          */
 594         public function getSources() {
 595                 return $this->sources;
 596         }
 597
 598         /**
 599          * Get the URL to the load.php endpoint for the given
 600          * ResourceLoader source
 601          *
 602          * @since 1.24
 603          * @param string $source
 604          * @throws MWException On an invalid $source name
 605          * @return string
 606          */
 607         public function getLoadScript( $source ) {
 608                 if ( !isset( $this->sources[$source] ) ) {
 609                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 610                 }
 611                 return $this->sources[$source];
 612         }
 613
 614         /**
 615          * @since 1.26
 616          * @param string $value
 617          * @return string Hash
 618          */
 619         public static function makeHash( $value ) {
 620                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 621                 // The first 8 chars of a base64 encoded digest represent the same binary as
 622                 // the first 12 chars of a hex encoded digest.
 623                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 624         }
 625
 626         /**
 627          * Helper method to get and combine versions of multiple modules.
 628          *
 629          * @since 1.26
 630          * @param ResourceLoaderContext $context
 631          * @param array $modules List of ResourceLoaderModule objects
 632          * @return string Hash
 633          */
 634         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 635                 if ( !$modules ) {
 636                         return '';
 637                 }
 638                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 639                 // http://php.net/functions.anonymous
 640                 $rl = $this;
 641                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 642                         return $rl->getModule( $module )->getVersionHash( $context );
 643                 }, $modules );
 644                 return self::makeHash( implode( $hashes ) );
 645         }
 646
 647         /**
 648          * Output a response to a load request, including the content-type header.
 649          *
 650          * @param ResourceLoaderContext $context Context in which a response should be formed
 651          */
 652         public function respond( ResourceLoaderContext $context ) {
 653                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 654                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 655                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 656                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 657                 // the whole thing in our own output buffer to be sure the active buffer
 658                 // doesn't use ob_gzhandler.
 659                 // See http://bugs.php.net/bug.php?id=36514
 660                 ob_start();
 661
 662                 // Find out which modules are missing and instantiate the others
 663                 $modules = array();
 664                 $missing = array();
 665                 foreach ( $context->getModules() as $name ) {
 666                         $module = $this->getModule( $name );
 667                         if ( $module ) {
 668                                 // Do not allow private modules to be loaded from the web.
 669                                 // This is a security issue, see bug 34907.
 670                                 if ( $module->getGroup() === 'private' ) {
 671                                         $this->logger->debug( "Request for private module '$name' denied" );
 672                                         $this->errors[] = "Cannot show private module \"$name\"";
 673                                         continue;
 674                                 }
 675                                 $modules[$name] = $module;
 676                         } else {
 677                                 $missing[] = $name;
 678                         }
 679                 }
 680
 681                 try {
 682                         // Preload for getCombinedVersion()
 683                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 684                 } catch ( Exception $e ) {
 685                         MWExceptionHandler::logException( $e );
 686                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 687                                 'exception' => $e
 688                         ) );
 689                         $this->errors[] = self::formatExceptionNoComment( $e );
 690                 }
 691
 692                 // Combine versions to propagate cache invalidation
 693                 $versionHash = '';
 694                 try {
 695                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 696                 } catch ( Exception $e ) {
 697                         MWExceptionHandler::logException( $e );
 698                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 699                                 'exception' => $e
 700                         ) );
 701                         $this->errors[] = self::formatExceptionNoComment( $e );
 702                 }
 703
 704                 // See RFC 2616 § 3.11 Entity Tags
 705                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 706                 $etag = 'W/"' . $versionHash . '"';
 707
 708                 // Try the client-side cache first
 709                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 710                         return; // output handled (buffers cleared)
 711                 }
 712
 713                 // Use file cache if enabled and available...
 714                 if ( $this->config->get( 'UseFileCache' ) ) {
 715                         $fileCache = ResourceFileCache::newFromContext( $context );
 716                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 717                                 return; // output handled
 718                         }
 719                 }
 720
 721                 // Generate a response
 722                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 723
 724                 // Capture any PHP warnings from the output buffer and append them to the
 725                 // error list if we're in debug mode.
 726                 if ( $context->getDebug() ) {
 727                         $warnings = ob_get_contents();
 728                         if ( strlen( $warnings ) ) {
 729                                 $this->errors[] = $warnings;
 730                         }
 731                 }
 732
 733                 // Save response to file cache unless there are errors
 734                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 735                         // Cache single modules and images...and other requests if there are enough hits
 736                         if ( ResourceFileCache::useFileCache( $context ) ) {
 737                                 if ( $fileCache->isCacheWorthy() ) {
 738                                         $fileCache->saveText( $response );
 739                                 } else {
 740                                         $fileCache->incrMissesRecent( $context->getRequest() );
 741                                 }
 742                         }
 743                 }
 744
 745                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 746
 747                 // Remove the output buffer and output the response
 748                 ob_end_clean();
 749
 750                 if ( $context->getImageObj() && $this->errors ) {
 751                         // We can't show both the error messages and the response when it's an image.
 752                         $response = implode( "\n\n", $this->errors );
 753                 } elseif ( $this->errors ) {
 754                         $errorText = implode( "\n\n", $this->errors );
 755                         $errorResponse = self::makeComment( $errorText );
 756                         if ( $context->shouldIncludeScripts() ) {
 757                                 $errorResponse .= 'if (window.console && console.error) {'
 758                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 759                                         . "}\n";
 760                         }
 761
 762                         // Prepend error info to the response
 763                         $response = $errorResponse . $response;
 764                 }
 765
 766                 $this->errors = array();
 767                 echo $response;
 768
 769         }
 770
 771         /**
 772          * Send main response headers to the client.
 773          *
 774          * Deals with Content-Type, CORS (for stylesheets), and caching.
 775          *
 776          * @param ResourceLoaderContext $context
 777          * @param string $etag ETag header value
 778          * @param bool $errors Whether there are errors in the response
 779          * @return void
 780          */
 781         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 782                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 783                 // If a version wasn't specified we need a shorter expiry time for updates
 784                 // to propagate to clients quickly
 785                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 786                 if ( is_null( $context->getVersion() ) || $errors ) {
 787                         $maxage = $rlMaxage['unversioned']['client'];
 788                         $smaxage = $rlMaxage['unversioned']['server'];
 789                 // If a version was specified we can use a longer expiry time since changing
 790                 // version numbers causes cache misses
 791                 } else {
 792                         $maxage = $rlMaxage['versioned']['client'];
 793                         $smaxage = $rlMaxage['versioned']['server'];
 794                 }
 795                 if ( $context->getImageObj() ) {
 796                         // Output different headers if we're outputting textual errors.
 797                         if ( $errors ) {
 798                                 header( 'Content-Type: text/plain; charset=utf-8' );
 799                         } else {
 800                                 $context->getImageObj()->sendResponseHeaders( $context );
 801                         }
 802                 } elseif ( $context->getOnly() === 'styles' ) {
 803                         header( 'Content-Type: text/css; charset=utf-8' );
 804                         header( 'Access-Control-Allow-Origin: *' );
 805                 } else {
 806                         header( 'Content-Type: text/javascript; charset=utf-8' );
 807                 }
 808                 // See RFC 2616 § 14.19 ETag
 809                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 810                 header( 'ETag: ' . $etag );
 811                 if ( $context->getDebug() ) {
 812                         // Do not cache debug responses
 813                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 814                         header( 'Pragma: no-cache' );
 815                 } else {
 816                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 817                         $exp = min( $maxage, $smaxage );
 818                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 819                 }
 820         }
 821
 822         /**
 823          * Respond with HTTP 304 Not Modified if appropiate.
 824          *
 825          * If there's an If-None-Match header, respond with a 304 appropriately
 826          * and clear out the output buffer. If the client cache is too old then do nothing.
 827          *
 828          * @param ResourceLoaderContext $context
 829          * @param string $etag ETag header value
 830          * @return bool True if HTTP 304 was sent and output handled
 831          */
 832         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 833                 // See RFC 2616 § 14.26 If-None-Match
 834                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 835                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 836                 // Never send 304s in debug mode
 837                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 838                         // There's another bug in ob_gzhandler (see also the comment at
 839                         // the top of this function) that causes it to gzip even empty
 840                         // responses, meaning it's impossible to produce a truly empty
 841                         // response (because the gzip header is always there). This is
 842                         // a problem because 304 responses have to be completely empty
 843                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 844                         // See also http://bugs.php.net/bug.php?id=51579
 845                         // To work around this, we tear down all output buffering before
 846                         // sending the 304.
 847                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 848
 849                         HttpStatus::header( 304 );
 850
 851                         $this->sendResponseHeaders( $context, $etag, false );
 852                         return true;
 853                 }
 854                 return false;
 855         }
 856
 857         /**
 858          * Send out code for a response from file cache if possible.
 859          *
 860          * @param ResourceFileCache $fileCache Cache object for this request URL
 861          * @param ResourceLoaderContext $context Context in which to generate a response
 862          * @param string $etag ETag header value
 863          * @return bool If this found a cache file and handled the response
 864          */
 865         protected function tryRespondFromFileCache(
 866                 ResourceFileCache $fileCache,
 867                 ResourceLoaderContext $context,
 868                 $etag
 869         ) {
 870                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 871                 // Buffer output to catch warnings.
 872                 ob_start();
 873                 // Get the maximum age the cache can be
 874                 $maxage = is_null( $context->getVersion() )
 875                         ? $rlMaxage['unversioned']['server']
 876                         : $rlMaxage['versioned']['server'];
 877                 // Minimum timestamp the cache file must have
 878                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 879                 if ( !$good ) {
 880                         try { // RL always hits the DB on file cache miss...
 881                                 wfGetDB( DB_SLAVE );
 882                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 883                                 $good = $fileCache->isCacheGood(); // cache existence check
 884                         }
 885                 }
 886                 if ( $good ) {
 887                         $ts = $fileCache->cacheTimestamp();
 888                         // Send content type and cache headers
 889                         $this->sendResponseHeaders( $context, $etag, false );
 890                         $response = $fileCache->fetchText();
 891                         // Capture any PHP warnings from the output buffer and append them to the
 892                         // response in a comment if we're in debug mode.
 893                         if ( $context->getDebug() ) {
 894                                 $warnings = ob_get_contents();
 895                                 if ( strlen( $warnings ) ) {
 896                                         $response = self::makeComment( $warnings ) . $response;
 897                                 }
 898                         }
 899                         // Remove the output buffer and output the response
 900                         ob_end_clean();
 901                         echo $response . "\n/* Cached {$ts} */";
 902                         return true; // cache hit
 903                 }
 904                 // Clear buffer
 905                 ob_end_clean();
 906
 907                 return false; // cache miss
 908         }
 909
 910         /**
 911          * Generate a CSS or JS comment block.
 912          *
 913          * Only use this for public data, not error message details.
 914          *
 915          * @param string $text
 916          * @return string
 917          */
 918         public static function makeComment( $text ) {
 919                 $encText = str_replace( '*/', '* /', $text );
 920                 return "/*\n$encText\n*/\n";
 921         }
 922
 923         /**
 924          * Handle exception display.
 925          *
 926          * @param Exception $e Exception to be shown to the user
 927          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 928          */
 929         public static function formatException( $e ) {
 930                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 931         }
 932
 933         /**
 934          * Handle exception display.
 935          *
 936          * @since 1.25
 937          * @param Exception $e Exception to be shown to the user
 938          * @return string Sanitized text that can be returned to the user
 939          */
 940         protected static function formatExceptionNoComment( $e ) {
 941                 global $wgShowExceptionDetails;
 942
 943                 if ( !$wgShowExceptionDetails ) {
 944                         return MWExceptionHandler::getPublicLogMessage( $e );
 945                 }
 946
 947                 return MWExceptionHandler::getLogMessage( $e );
 948         }
 949
 950         /**
 951          * Generate code for a response.
 952          *
 953          * @param ResourceLoaderContext $context Context in which to generate a response
 954          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 955          * @param string[] $missing List of requested module names that are unregistered (optional)
 956          * @return string Response data
 957          */
 958         public function makeModuleResponse( ResourceLoaderContext $context,
 959                 array $modules, array $missing = array()
 960         ) {
 961                 $out = '';
 962                 $states = array();
 963
 964                 if ( !count( $modules ) && !count( $missing ) ) {
 965                         return <<<MESSAGE
 966 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 967    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 968    no modules were requested. Max made me put this here. */
 969 MESSAGE;
 970                 }
 971
 972                 $image = $context->getImageObj();
 973                 if ( $image ) {
 974                         $data = $image->getImageData( $context );
 975                         if ( $data === false ) {
 976                                 $data = '';
 977                                 $this->errors[] = 'Image generation failed';
 978                         }
 979                         return $data;
 980                 }
 981
 982                 // Pre-fetch blobs
 983                 if ( $context->shouldIncludeMessages() ) {
 984                         try {
 985                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 986                         } catch ( Exception $e ) {
 987                                 MWExceptionHandler::logException( $e );
 988                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 989                                         'exception' => $e
 990                                 ) );
 991                                 $this->errors[] = self::formatExceptionNoComment( $e );
 992                         }
 993                 }
 994
 995                 foreach ( $missing as $name ) {
 996                         $states[$name] = 'missing';
 997                 }
 998
 999                 // Generate output
1000                 $isRaw = false;
1001
1002                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
1003
1004                 foreach ( $modules as $name => $module ) {
1005                         try {
1006                                 $content = $module->getModuleContent( $context );
1007                                 $strContent = '';
1008
1009                                 // Append output
1010                                 switch ( $context->getOnly() ) {
1011                                         case 'scripts':
1012                                                 $scripts = $content['scripts'];
1013                                                 if ( is_string( $scripts ) ) {
1014                                                         // Load scripts raw...
1015                                                         $strContent = $scripts;
1016                                                 } elseif ( is_array( $scripts ) ) {
1017                                                         // ...except when $scripts is an array of URLs
1018                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
1019                                                 }
1020                                                 break;
1021                                         case 'styles':
1022                                                 $styles = $content['styles'];
1023                                                 // We no longer seperate into media, they are all combined now with
1024                                                 // custom media type groups into @media .. {} sections as part of the css string.
1025                                                 // Module returns either an empty array or a numerical array with css strings.
1026                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1027                                                 break;
1028                                         default:
1029                                                 $strContent = self::makeLoaderImplementScript(
1030                                                         $name,
1031                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1032                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1033                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1034                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1035                                                 );
1036                                                 break;
1037                                 }
1038
1039                                 if ( !$context->getDebug() ) {
1040                                         $strContent = self::filter( $filter, $strContent );
1041                                 }
1042
1043                                 $out .= $strContent;
1044
1045                         } catch ( Exception $e ) {
1046                                 MWExceptionHandler::logException( $e );
1047                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1048                                         'exception' => $e
1049                                 ) );
1050                                 $this->errors[] = self::formatExceptionNoComment( $e );
1051
1052                                 // Respond to client with error-state instead of module implementation
1053                                 $states[$name] = 'error';
1054                                 unset( $modules[$name] );
1055                         }
1056                         $isRaw |= $module->isRaw();
1057                 }
1058
1059                 // Update module states
1060                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1061                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1062                                 // Set the state of modules loaded as only scripts to ready as
1063                                 // they don't have an mw.loader.implement wrapper that sets the state
1064                                 foreach ( $modules as $name => $module ) {
1065                                         $states[$name] = 'ready';
1066                                 }
1067                         }
1068
1069                         // Set the state of modules we didn't respond to with mw.loader.implement
1070                         if ( count( $states ) ) {
1071                                 $stateScript = self::makeLoaderStateScript( $states );
1072                                 if ( !$context->getDebug() ) {
1073                                         $stateScript = self::filter( 'minify-js', $stateScript );
1074                                 }
1075                                 $out .= $stateScript;
1076                         }
1077                 } else {
1078                         if ( count( $states ) ) {
1079                                 $this->errors[] = 'Problematic modules: ' .
1080                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1081                         }
1082                 }
1083
1084                 return $out;
1085         }
1086
1087         /**
1088          * Get names of modules that use a certain message.
1089          *
1090          * @param string $messageKey
1091          * @return array List of module names
1092          */
1093         public function getModulesByMessage( $messageKey ) {
1094                 $moduleNames = array();
1095                 foreach ( $this->getModuleNames() as $moduleName ) {
1096                         $module = $this->getModule( $moduleName );
1097                         if ( in_array( $messageKey, $module->getMessages() ) ) {
1098                                 $moduleNames[] = $moduleName;
1099                         }
1100                 }
1101                 return $moduleNames;
1102         }
1103
1104         /* Static Methods */
1105
1106         /**
1107          * Return JS code that calls mw.loader.implement with given module properties.
1108          *
1109          * @param string $name Module name
1110          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1111          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1112          *   to CSS files keyed by media type
1113          * @param mixed $messages List of messages associated with this module. May either be an
1114          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1115          *   the same data, wrapped in an XmlJsCode object.
1116          * @param array $templates Keys are name of templates and values are the source of
1117          *   the template.
1118          * @throws MWException
1119          * @return string
1120          */
1121         public static function makeLoaderImplementScript(
1122                 $name, $scripts, $styles, $messages, $templates
1123         ) {
1124                 if ( is_string( $scripts ) ) {
1125                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1126                         // Transportation as string instructs mw.loader.implement to use globalEval.
1127                         if ( $name === 'site' || $name === 'user' ) {
1128                                 // Minify manually because the general makeModuleResponse() minification won't be
1129                                 // effective here due to the script being a string instead of a function. (T107377)
1130                                 if ( !ResourceLoader::inDebugMode() ) {
1131                                         $scripts = self::filter( 'minify-js', $scripts );
1132                                 }
1133                         } else {
1134                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1135                         }
1136                 } elseif ( !is_array( $scripts ) ) {
1137                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1138                 }
1139                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1140                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1141                 // of "{}". Force them to objects.
1142                 $module = array(
1143                         $name,
1144                         $scripts,
1145                         (object)$styles,
1146                         (object)$messages,
1147                         (object)$templates,
1148                 );
1149                 self::trimArray( $module );
1150
1151                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1152         }
1153
1154         /**
1155          * Returns JS code which, when called, will register a given list of messages.
1156          *
1157          * @param mixed $messages Either an associative array mapping message key to value, or a
1158          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1159          * @return string
1160          */
1161         public static function makeMessageSetScript( $messages ) {
1162                 return Xml::encodeJsCall(
1163                         'mw.messages.set',
1164                         array( (object)$messages ),
1165                         ResourceLoader::inDebugMode()
1166                 );
1167         }
1168
1169         /**
1170          * Combines an associative array mapping media type to CSS into a
1171          * single stylesheet with "@media" blocks.
1172          *
1173          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1174          * @return array
1175          */
1176         public static function makeCombinedStyles( array $stylePairs ) {
1177                 $out = array();
1178                 foreach ( $stylePairs as $media => $styles ) {
1179                         // ResourceLoaderFileModule::getStyle can return the styles
1180                         // as a string or an array of strings. This is to allow separation in
1181                         // the front-end.
1182                         $styles = (array)$styles;
1183                         foreach ( $styles as $style ) {
1184                                 $style = trim( $style );
1185                                 // Don't output an empty "@media print { }" block (bug 40498)
1186                                 if ( $style !== '' ) {
1187                                         // Transform the media type based on request params and config
1188                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1189                                         $media = OutputPage::transformCssMedia( $media );
1190
1191                                         if ( $media === '' || $media == 'all' ) {
1192                                                 $out[] = $style;
1193                                         } elseif ( is_string( $media ) ) {
1194                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1195                                         }
1196                                         // else: skip
1197                                 }
1198                         }
1199                 }
1200                 return $out;
1201         }
1202
1203         /**
1204          * Returns a JS call to mw.loader.state, which sets the state of a
1205          * module or modules to a given value. Has two calling conventions:
1206          *
1207          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1208          *         Set the state of a single module called $name to $state
1209          *
1210          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1211          *         Set the state of modules with the given names to the given states
1212          *
1213          * @param string $name
1214          * @param string $state
1215          * @return string
1216          */
1217         public static function makeLoaderStateScript( $name, $state = null ) {
1218                 if ( is_array( $name ) ) {
1219                         return Xml::encodeJsCall(
1220                                 'mw.loader.state',
1221                                 array( $name ),
1222                                 ResourceLoader::inDebugMode()
1223                         );
1224                 } else {
1225                         return Xml::encodeJsCall(
1226                                 'mw.loader.state',
1227                                 array( $name, $state ),
1228                                 ResourceLoader::inDebugMode()
1229                         );
1230                 }
1231         }
1232
1233         /**
1234          * Returns JS code which calls the script given by $script. The script will
1235          * be called with local variables name, version, dependencies and group,
1236          * which will have values corresponding to $name, $version, $dependencies
1237          * and $group as supplied.
1238          *
1239          * @param string $name Module name
1240          * @param string $version Module version hash
1241          * @param array $dependencies List of module names on which this module depends
1242          * @param string $group Group which the module is in.
1243          * @param string $source Source of the module, or 'local' if not foreign.
1244          * @param string $script JavaScript code
1245          * @return string
1246          */
1247         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1248                 $group, $source, $script
1249         ) {
1250                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1251                 return Xml::encodeJsCall(
1252                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1253                         array( $name, $version, $dependencies, $group, $source ),
1254                         ResourceLoader::inDebugMode()
1255                 );
1256         }
1257
1258         private static function isEmptyObject( stdClass $obj ) {
1259                 foreach ( $obj as $key => $value ) {
1260                         return false;
1261                 }
1262                 return true;
1263         }
1264
1265         /**
1266          * Remove empty values from the end of an array.
1267          *
1268          * Values considered empty:
1269          *
1270          * - null
1271          * - array()
1272          * - new XmlJsCode( '{}' )
1273          * - new stdClass() // (object) array()
1274          *
1275          * @param Array $array
1276          */
1277         private static function trimArray( Array &$array ) {
1278                 $i = count( $array );
1279                 while ( $i-- ) {
1280                         if ( $array[$i] === null
1281                                 || $array[$i] === array()
1282                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1283                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1284                         ) {
1285                                 unset( $array[$i] );
1286                         } else {
1287                                 break;
1288                         }
1289                 }
1290         }
1291
1292         /**
1293          * Returns JS code which calls mw.loader.register with the given
1294          * parameters. Has three calling conventions:
1295          *
1296          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1297          *        $dependencies, $group, $source, $skip
1298          *     ):
1299          *        Register a single module.
1300          *
1301          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1302          *        Register modules with the given names.
1303          *
1304          *   - ResourceLoader::makeLoaderRegisterScript( array(
1305          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1306          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1307          *        ...
1308          *     ) ):
1309          *        Registers modules with the given names and parameters.
1310          *
1311          * @param string $name Module name
1312          * @param string $version Module version hash
1313          * @param array $dependencies List of module names on which this module depends
1314          * @param string $group Group which the module is in
1315          * @param string $source Source of the module, or 'local' if not foreign
1316          * @param string $skip Script body of the skip function
1317          * @return string
1318          */
1319         public static function makeLoaderRegisterScript( $name, $version = null,
1320                 $dependencies = null, $group = null, $source = null, $skip = null
1321         ) {
1322                 if ( is_array( $name ) ) {
1323                         // Build module name index
1324                         $index = array();
1325                         foreach ( $name as $i => &$module ) {
1326                                 $index[$module[0]] = $i;
1327                         }
1328
1329                         // Transform dependency names into indexes when possible, they will be resolved by
1330                         // mw.loader.register on the other end
1331                         foreach ( $name as &$module ) {
1332                                 if ( isset( $module[2] ) ) {
1333                                         foreach ( $module[2] as &$dependency ) {
1334                                                 if ( isset( $index[$dependency] ) ) {
1335                                                         $dependency = $index[$dependency];
1336                                                 }
1337                                         }
1338                                 }
1339                         }
1340
1341                         array_walk( $name, array( 'self', 'trimArray' ) );
1342
1343                         return Xml::encodeJsCall(
1344                                 'mw.loader.register',
1345                                 array( $name ),
1346                                 ResourceLoader::inDebugMode()
1347                         );
1348                 } else {
1349                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1350                         self::trimArray( $registration );
1351                         return Xml::encodeJsCall(
1352                                 'mw.loader.register',
1353                                 $registration,
1354                                 ResourceLoader::inDebugMode()
1355                         );
1356                 }
1357         }
1358
1359         /**
1360          * Returns JS code which calls mw.loader.addSource() with the given
1361          * parameters. Has two calling conventions:
1362          *
1363          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1364          *       Register a single source
1365          *
1366          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1367          *       Register sources with the given IDs and properties.
1368          *
1369          * @param string $id Source ID
1370          * @param array $properties Source properties (see addSource())
1371          * @return string
1372          */
1373         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1374                 if ( is_array( $id ) ) {
1375                         return Xml::encodeJsCall(
1376                                 'mw.loader.addSource',
1377                                 array( $id ),
1378                                 ResourceLoader::inDebugMode()
1379                         );
1380                 } else {
1381                         return Xml::encodeJsCall(
1382                                 'mw.loader.addSource',
1383                                 array( $id, $properties ),
1384                                 ResourceLoader::inDebugMode()
1385                         );
1386                 }
1387         }
1388
1389         /**
1390          * Returns JS code which runs given JS code if the client-side framework is
1391          * present.
1392          *
1393          * @deprecated since 1.25; use makeInlineScript instead
1394          * @param string $script JavaScript code
1395          * @return string
1396          */
1397         public static function makeLoaderConditionalScript( $script ) {
1398                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1399                         trim( $script ) . "\n} );";
1400         }
1401
1402         /**
1403          * Construct an inline script tag with given JS code.
1404          *
1405          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1406          * only if the client has adequate support for MediaWiki JavaScript code.
1407          *
1408          * @param string $script JavaScript code
1409          * @return WrappedString HTML
1410          */
1411         public static function makeInlineScript( $script ) {
1412                 $js = self::makeLoaderConditionalScript( $script );
1413                 return new WrappedString(
1414                         Html::inlineScript( $js ),
1415                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1416                         "\n} );</script>"
1417                 );
1418         }
1419
1420         /**
1421          * Returns JS code which will set the MediaWiki configuration array to
1422          * the given value.
1423          *
1424          * @param array $configuration List of configuration values keyed by variable name
1425          * @return string
1426          */
1427         public static function makeConfigSetScript( array $configuration ) {
1428                 return Xml::encodeJsCall(
1429                         'mw.config.set',
1430                         array( $configuration ),
1431                         ResourceLoader::inDebugMode()
1432                 ) . ResourceLoader::FILTER_NOMIN;
1433         }
1434
1435         /**
1436          * Convert an array of module names to a packed query string.
1437          *
1438          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1439          * becomes 'foo.bar,baz|bar.baz,quux'
1440          * @param array $modules List of module names (strings)
1441          * @return string Packed query string
1442          */
1443         public static function makePackedModulesString( $modules ) {
1444                 $groups = array(); // array( prefix => array( suffixes ) )
1445                 foreach ( $modules as $module ) {
1446                         $pos = strrpos( $module, '.' );
1447                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1448                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1449                         $groups[$prefix][] = $suffix;
1450                 }
1451
1452                 $arr = array();
1453                 foreach ( $groups as $prefix => $suffixes ) {
1454                         $p = $prefix === '' ? '' : $prefix . '.';
1455                         $arr[] = $p . implode( ',', $suffixes );
1456                 }
1457                 $str = implode( '|', $arr );
1458                 return $str;
1459         }
1460
1461         /**
1462          * Determine whether debug mode was requested
1463          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1464          * @return bool
1465          */
1466         public static function inDebugMode() {
1467                 if ( self::$debugMode === null ) {
1468                         global $wgRequest, $wgResourceLoaderDebug;
1469                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1470                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1471                         );
1472                 }
1473                 return self::$debugMode;
1474         }
1475
1476         /**
1477          * Reset static members used for caching.
1478          *
1479          * Global state and $wgRequest are evil, but we're using it right
1480          * now and sometimes we need to be able to force ResourceLoader to
1481          * re-evaluate the context because it has changed (e.g. in the test suite).
1482          */
1483         public static function clearCache() {
1484                 self::$debugMode = null;
1485         }
1486
1487         /**
1488          * Build a load.php URL
1489          *
1490          * @since 1.24
1491          * @param string $source Name of the ResourceLoader source
1492          * @param ResourceLoaderContext $context
1493          * @param array $extraQuery
1494          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1495          */
1496         public function createLoaderURL( $source, ResourceLoaderContext $context,
1497                 $extraQuery = array()
1498         ) {
1499                 $query = self::createLoaderQuery( $context, $extraQuery );
1500                 $script = $this->getLoadScript( $source );
1501
1502                 return wfAppendQuery( $script, $query );
1503         }
1504
1505         /**
1506          * Build a load.php URL
1507          * @deprecated since 1.24 Use createLoaderURL() instead
1508          * @param array $modules Array of module names (strings)
1509          * @param string $lang Language code
1510          * @param string $skin Skin name
1511          * @param string|null $user User name. If null, the &user= parameter is omitted
1512          * @param string|null $version Versioning timestamp
1513          * @param bool $debug Whether the request should be in debug mode
1514          * @param string|null $only &only= parameter
1515          * @param bool $printable Printable mode
1516          * @param bool $handheld Handheld mode
1517          * @param array $extraQuery Extra query parameters to add
1518          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1519          */
1520         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1521                 $version = null, $debug = false, $only = null, $printable = false,
1522                 $handheld = false, $extraQuery = array()
1523         ) {
1524                 global $wgLoadScript;
1525
1526                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1527                         $only, $printable, $handheld, $extraQuery
1528                 );
1529
1530                 return wfAppendQuery( $wgLoadScript, $query );
1531         }
1532
1533         /**
1534          * Helper for createLoaderURL()
1535          *
1536          * @since 1.24
1537          * @see makeLoaderQuery
1538          * @param ResourceLoaderContext $context
1539          * @param array $extraQuery
1540          * @return array
1541          */
1542         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1543                 return self::makeLoaderQuery(
1544                         $context->getModules(),
1545                         $context->getLanguage(),
1546                         $context->getSkin(),
1547                         $context->getUser(),
1548                         $context->getVersion(),
1549                         $context->getDebug(),
1550                         $context->getOnly(),
1551                         $context->getRequest()->getBool( 'printable' ),
1552                         $context->getRequest()->getBool( 'handheld' ),
1553                         $extraQuery
1554                 );
1555         }
1556
1557         /**
1558          * Build a query array (array representation of query string) for load.php. Helper
1559          * function for makeLoaderURL().
1560          *
1561          * @param array $modules
1562          * @param string $lang
1563          * @param string $skin
1564          * @param string $user
1565          * @param string $version
1566          * @param bool $debug
1567          * @param string $only
1568          * @param bool $printable
1569          * @param bool $handheld
1570          * @param array $extraQuery
1571          *
1572          * @return array
1573          */
1574         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1575                 $version = null, $debug = false, $only = null, $printable = false,
1576                 $handheld = false, $extraQuery = array()
1577         ) {
1578                 $query = array(
1579                         'modules' => self::makePackedModulesString( $modules ),
1580                         'lang' => $lang,
1581                         'skin' => $skin,
1582                         'debug' => $debug ? 'true' : 'false',
1583                 );
1584                 if ( $user !== null ) {
1585                         $query['user'] = $user;
1586                 }
1587                 if ( $version !== null ) {
1588                         $query['version'] = $version;
1589                 }
1590                 if ( $only !== null ) {
1591                         $query['only'] = $only;
1592                 }
1593                 if ( $printable ) {
1594                         $query['printable'] = 1;
1595                 }
1596                 if ( $handheld ) {
1597                         $query['handheld'] = 1;
1598                 }
1599                 $query += $extraQuery;
1600
1601                 // Make queries uniform in order
1602                 ksort( $query );
1603                 return $query;
1604         }
1605
1606         /**
1607          * Check a module name for validity.
1608          *
1609          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1610          * at most 255 bytes.
1611          *
1612          * @param string $moduleName Module name to check
1613          * @return bool Whether $moduleName is a valid module name
1614          */
1615         public static function isValidModuleName( $moduleName ) {
1616                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1617         }
1618
1619         /**
1620          * Returns LESS compiler set up for use with MediaWiki
1621          *
1622          * @since 1.22
1623          * @since 1.27 added $extraVars parameter
1624          * @param Config $config
1625          * @param array $extraVars Associative array of extra (i.e., other than the
1626          *   globally-configured ones) that should be used for compilation.
1627          * @throws MWException
1628          * @return Less_Parser
1629          */
1630         public static function getLessCompiler( Config $config, $extraVars = array() ) {
1631                 // When called from the installer, it is possible that a required PHP extension
1632                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1633                 // exception (caught by the installer) to prevent a fatal error later on.
1634                 if ( !class_exists( 'Less_Parser' ) ) {
1635                         throw new MWException( 'MediaWiki requires the less.php parser' );
1636                 }
1637
1638                 $parser = new Less_Parser;
1639                 $parser->ModifyVars( array_merge( self::getLessVars( $config ), $extraVars ) );
1640                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1641                 $parser->SetOption( 'relativeUrls', false );
1642                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1643
1644                 return $parser;
1645         }
1646
1647         /**
1648          * Get global LESS variables.
1649          *
1650          * @param Config $config
1651          * @since 1.22
1652          * @return array Map of variable names to string CSS values.
1653          */
1654         public static function getLessVars( Config $config ) {
1655                 if ( !self::$lessVars ) {
1656                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1657                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1658                         self::$lessVars = $lessVars;
1659                 }
1660                 return self::$lessVars;
1661         }
1662 }