includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 use Psr\Log\LoggerAwareInterface;
  26 use Psr\Log\LoggerInterface;
  27 use Psr\Log\NullLogger;
  28 use WrappedString\WrappedString;
  29
  30 /**
  31  * Dynamic JavaScript and CSS resource loading system.
  32  *
  33  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  34  *    https://www.mediawiki.org/wiki/ResourceLoader
  35  */
  36 class ResourceLoader implements LoggerAwareInterface {
  37         /** @var int */
  38         protected static $filterCacheVersion = 7;
  39
  40         /** @var bool */
  41         protected static $debugMode = null;
  42
  43         /** @var array */
  44         private $lessVars = null;
  45
  46         /**
  47          * Module name/ResourceLoaderModule object pairs
  48          * @var array
  49          */
  50         protected $modules = 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 $moduleNames List of module names to preload information for
 105          * @param ResourceLoaderContext $context Context to load the information within
 106          */
 107         public function preloadModuleInfo( array $moduleNames, ResourceLoaderContext $context ) {
 108                 if ( !$moduleNames ) {
 109                         // Or else Database*::select() will explode, plus it's cheaper!
 110                         return;
 111                 }
 112                 $dbr = wfGetDB( DB_SLAVE );
 113                 $skin = $context->getSkin();
 114                 $lang = $context->getLanguage();
 115
 116                 // Batched version of ResourceLoaderModule::getFileDependencies
 117                 $vary = "$skin|$lang";
 118                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 119                                 'md_module' => $moduleNames,
 120                                 'md_skin' => $vary,
 121                         ), __METHOD__
 122                 );
 123
 124                 // Prime in-object cache for file dependencies
 125                 $modulesWithDeps = array();
 126                 foreach ( $res as $row ) {
 127                         $module = $this->getModule( $row->md_module );
 128                         if ( $module ) {
 129                                 $module->setFileDependencies( $context, ResourceLoaderModule::expandRelativePaths(
 130                                         FormatJson::decode( $row->md_deps, true )
 131                                 ) );
 132                                 $modulesWithDeps[] = $row->md_module;
 133                         }
 134                 }
 135                 // Register the absence of a dependency row too
 136                 foreach ( array_diff( $moduleNames, $modulesWithDeps ) as $name ) {
 137                         $module = $this->getModule( $name );
 138                         if ( $module ) {
 139                                 $this->getModule( $name )->setFileDependencies( $context, array() );
 140                         }
 141                 }
 142
 143                 // Prime in-object cache for message blobs for modules with messages
 144                 $modules = array();
 145                 foreach ( $moduleNames as $name ) {
 146                         $module = $this->getModule( $name );
 147                         if ( $module && $module->getMessages() ) {
 148                                 $modules[$name] = $module;
 149                         }
 150                 }
 151                 $store = $this->getMessageBlobStore();
 152                 $blobs = $store->getBlobs( $modules, $lang );
 153                 foreach ( $blobs as $name => $blob ) {
 154                         $modules[$name]->setMessageBlob( $blob, $lang );
 155                 }
 156         }
 157
 158         /**
 159          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 160          *
 161          * Available filters are:
 162          *
 163          *    - minify-js \see JavaScriptMinifier::minify
 164          *    - minify-css \see CSSMin::minify
 165          *
 166          * If $data is empty, only contains whitespace or the filter was unknown,
 167          * $data is returned unmodified.
 168          *
 169          * @param string $filter Name of filter to run
 170          * @param string $data Text to filter, such as JavaScript or CSS text
 171          * @param array $options Keys:
 172          *  - (bool) cache: Whether to allow caching this data. Default: true.
 173          * @return string Filtered data, or a comment containing an error message
 174          */
 175         public static function filter( $filter, $data, Array $options = array() ) {
 176                 if ( strpos( $data, ResourceLoader::FILTER_NOMIN ) !== false ) {
 177                         return $data;
 178                 }
 179
 180                 if ( isset( $options['cache'] ) && $options['cache'] === false ) {
 181                         return self::applyFilter( $filter, $data );
 182                 }
 183
 184                 $stats = RequestContext::getMain()->getStats();
 185                 $cache = ObjectCache::getLocalServerInstance( CACHE_ANYTHING );
 186
 187                 $key = $cache->makeGlobalKey(
 188                         'resourceloader',
 189                         'filter',
 190                         $filter,
 191                         self::$filterCacheVersion, md5( $data )
 192                 );
 193
 194                 $result = $cache->get( $key );
 195                 if ( $result === false ) {
 196                         $stats->increment( "resourceloader_cache.$filter.miss" );
 197                         $result = self::applyFilter( $filter, $data );
 198                         $cache->set( $key, $result, 24 * 3600 );
 199                 } else {
 200                         $stats->increment( "resourceloader_cache.$filter.hit" );
 201                 }
 202                 if ( $result === null ) {
 203                         // Cached failure
 204                         $result = $data;
 205                 }
 206
 207                 return $result;
 208         }
 209
 210         private static function applyFilter( $filter, $data ) {
 211                 $data = trim( $data );
 212                 if ( $data ) {
 213                         try {
 214                                 $data = ( $filter === 'minify-css' )
 215                                         ? CSSMin::minify( $data )
 216                                         : JavaScriptMinifier::minify( $data );
 217                         } catch ( Exception $e ) {
 218                                 MWExceptionHandler::logException( $e );
 219                                 return null;
 220                         }
 221                 }
 222                 return $data;
 223         }
 224
 225         /* Methods */
 226
 227         /**
 228          * Register core modules and runs registration hooks.
 229          * @param Config $config [optional]
 230          * @param LoggerInterface $logger [optional]
 231          */
 232         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 233                 global $IP;
 234
 235                 $this->logger = $logger ?: new NullLogger();
 236
 237                 if ( !$config ) {
 238                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 239                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 240                 }
 241                 $this->config = $config;
 242
 243                 // Add 'local' source first
 244                 $this->addSource( 'local', wfScript( 'load' ) );
 245
 246                 // Add other sources
 247                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 248
 249                 // Register core modules
 250                 $this->register( include "$IP/resources/Resources.php" );
 251                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 252                 // Register extension modules
 253                 $this->register( $config->get( 'ResourceModules' ) );
 254                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 255
 256                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 257                         $this->registerTestModules();
 258                 }
 259
 260                 $this->setMessageBlobStore( new MessageBlobStore( $this, $this->logger ) );
 261         }
 262
 263         /**
 264          * @return Config
 265          */
 266         public function getConfig() {
 267                 return $this->config;
 268         }
 269
 270         /**
 271          * @since 1.26
 272          * @param LoggerInterface $logger
 273          */
 274         public function setLogger( LoggerInterface $logger ) {
 275                 $this->logger = $logger;
 276         }
 277
 278         /**
 279          * @since 1.27
 280          * @return LoggerInterface
 281          */
 282         public function getLogger() {
 283                 return $this->logger;
 284         }
 285
 286         /**
 287          * @since 1.26
 288          * @return MessageBlobStore
 289          */
 290         public function getMessageBlobStore() {
 291                 return $this->blobStore;
 292         }
 293
 294         /**
 295          * @since 1.25
 296          * @param MessageBlobStore $blobStore
 297          */
 298         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 299                 $this->blobStore = $blobStore;
 300         }
 301
 302         /**
 303          * Register a module with the ResourceLoader system.
 304          *
 305          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 306          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 307          *   this may also be a ResourceLoaderModule object. Optional when using
 308          *   multiple-registration calling style.
 309          * @throws MWException If a duplicate module registration is attempted
 310          * @throws MWException If a module name contains illegal characters (pipes or commas)
 311          * @throws MWException If something other than a ResourceLoaderModule is being registered
 312          * @return bool False if there were any errors, in which case one or more modules were
 313          *   not registered
 314          */
 315         public function register( $name, $info = null ) {
 316
 317                 // Allow multiple modules to be registered in one call
 318                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 319                 foreach ( $registrations as $name => $info ) {
 320                         // Warn on duplicate registrations
 321                         if ( isset( $this->moduleInfos[$name] ) ) {
 322                                 // A module has already been registered by this name
 323                                 $this->logger->warning(
 324                                         'ResourceLoader duplicate registration warning. ' .
 325                                         'Another module has already been registered as ' . $name
 326                                 );
 327                         }
 328
 329                         // Check $name for validity
 330                         if ( !self::isValidModuleName( $name ) ) {
 331                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 332                                         . "see ResourceLoader::isValidModuleName()" );
 333                         }
 334
 335                         // Attach module
 336                         if ( $info instanceof ResourceLoaderModule ) {
 337                                 $this->moduleInfos[$name] = array( 'object' => $info );
 338                                 $info->setName( $name );
 339                                 $this->modules[$name] = $info;
 340                         } elseif ( is_array( $info ) ) {
 341                                 // New calling convention
 342                                 $this->moduleInfos[$name] = $info;
 343                         } else {
 344                                 throw new MWException(
 345                                         'ResourceLoader module info type error for module \'' . $name .
 346                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 347                                 );
 348                         }
 349
 350                         // Last-minute changes
 351
 352                         // Apply custom skin-defined styles to existing modules.
 353                         if ( $this->isFileModule( $name ) ) {
 354                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 355                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 356                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 357                                                 continue;
 358                                         }
 359
 360                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 361                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 362                                         if ( isset( $skinStyles[$name] ) ) {
 363                                                 $paths = (array)$skinStyles[$name];
 364                                                 $styleFiles = array();
 365                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 366                                                 $paths = (array)$skinStyles['+' . $name];
 367                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 368                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 369                                                         array();
 370                                         } else {
 371                                                 continue;
 372                                         }
 373
 374                                         // Add new file paths, remapping them to refer to our directories and not use settings
 375                                         // from the module we're modifying, which come from the base definition.
 376                                         list( $localBasePath, $remoteBasePath ) =
 377                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 378
 379                                         foreach ( $paths as $path ) {
 380                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 381                                         }
 382
 383                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 384                                 }
 385                         }
 386                 }
 387
 388         }
 389
 390         /**
 391          */
 392         public function registerTestModules() {
 393                 global $IP;
 394
 395                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 396                         throw new MWException( 'Attempt to register JavaScript test modules '
 397                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 398                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 399                 }
 400
 401                 // Get core test suites
 402                 $testModules = array();
 403                 $testModules['qunit'] = array();
 404                 // Get other test suites (e.g. from extensions)
 405                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 406
 407                 // Add the testrunner (which configures QUnit) to the dependencies.
 408                 // Since it must be ready before any of the test suites are executed.
 409                 foreach ( $testModules['qunit'] as &$module ) {
 410                         // Make sure all test modules are top-loading so that when QUnit starts
 411                         // on document-ready, it will run once and finish. If some tests arrive
 412                         // later (possibly after QUnit has already finished) they will be ignored.
 413                         $module['position'] = 'top';
 414                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 415                 }
 416
 417                 $testModules['qunit'] =
 418                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 419
 420                 foreach ( $testModules as $id => $names ) {
 421                         // Register test modules
 422                         $this->register( $testModules[$id] );
 423
 424                         // Keep track of their names so that they can be loaded together
 425                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 426                 }
 427
 428         }
 429
 430         /**
 431          * Add a foreign source of modules.
 432          *
 433          * Source IDs are typically the same as the Wiki ID or database name (e.g. lowercase a-z).
 434          *
 435          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 436          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 437          *  backwards-compatibility.
 438          * @throws MWException
 439          */
 440         public function addSource( $id, $loadUrl = null ) {
 441                 // Allow multiple sources to be registered in one call
 442                 if ( is_array( $id ) ) {
 443                         foreach ( $id as $key => $value ) {
 444                                 $this->addSource( $key, $value );
 445                         }
 446                         return;
 447                 }
 448
 449                 // Disallow duplicates
 450                 if ( isset( $this->sources[$id] ) ) {
 451                         throw new MWException(
 452                                 'ResourceLoader duplicate source addition error. ' .
 453                                 'Another source has already been registered as ' . $id
 454                         );
 455                 }
 456
 457                 // Pre 1.24 backwards-compatibility
 458                 if ( is_array( $loadUrl ) ) {
 459                         if ( !isset( $loadUrl['loadScript'] ) ) {
 460                                 throw new MWException(
 461                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 462                                 );
 463                         }
 464
 465                         $loadUrl = $loadUrl['loadScript'];
 466                 }
 467
 468                 $this->sources[$id] = $loadUrl;
 469         }
 470
 471         /**
 472          * Get a list of module names.
 473          *
 474          * @return array List of module names
 475          */
 476         public function getModuleNames() {
 477                 return array_keys( $this->moduleInfos );
 478         }
 479
 480         /**
 481          * Get a list of test module names for one (or all) frameworks.
 482          *
 483          * If the given framework id is unknkown, or if the in-object variable is not an array,
 484          * then it will return an empty array.
 485          *
 486          * @param string $framework Get only the test module names for one
 487          *   particular framework (optional)
 488          * @return array
 489          */
 490         public function getTestModuleNames( $framework = 'all' ) {
 491                 /** @todo api siteinfo prop testmodulenames modulenames */
 492                 if ( $framework == 'all' ) {
 493                         return $this->testModuleNames;
 494                 } elseif ( isset( $this->testModuleNames[$framework] )
 495                         && is_array( $this->testModuleNames[$framework] )
 496                 ) {
 497                         return $this->testModuleNames[$framework];
 498                 } else {
 499                         return array();
 500                 }
 501         }
 502
 503         /**
 504          * Check whether a ResourceLoader module is registered
 505          *
 506          * @since 1.25
 507          * @param string $name
 508          * @return bool
 509          */
 510         public function isModuleRegistered( $name ) {
 511                 return isset( $this->moduleInfos[$name] );
 512         }
 513
 514         /**
 515          * Get the ResourceLoaderModule object for a given module name.
 516          *
 517          * If an array of module parameters exists but a ResourceLoaderModule object has not
 518          * yet been instantiated, this method will instantiate and cache that object such that
 519          * subsequent calls simply return the same object.
 520          *
 521          * @param string $name Module name
 522          * @return ResourceLoaderModule|null If module has been registered, return a
 523          *  ResourceLoaderModule instance. Otherwise, return null.
 524          */
 525         public function getModule( $name ) {
 526                 if ( !isset( $this->modules[$name] ) ) {
 527                         if ( !isset( $this->moduleInfos[$name] ) ) {
 528                                 // No such module
 529                                 return null;
 530                         }
 531                         // Construct the requested object
 532                         $info = $this->moduleInfos[$name];
 533                         /** @var ResourceLoaderModule $object */
 534                         if ( isset( $info['object'] ) ) {
 535                                 // Object given in info array
 536                                 $object = $info['object'];
 537                         } else {
 538                                 if ( !isset( $info['class'] ) ) {
 539                                         $class = 'ResourceLoaderFileModule';
 540                                 } else {
 541                                         $class = $info['class'];
 542                                 }
 543                                 /** @var ResourceLoaderModule $object */
 544                                 $object = new $class( $info );
 545                                 $object->setConfig( $this->getConfig() );
 546                                 $object->setLogger( $this->logger );
 547                         }
 548                         $object->setName( $name );
 549                         $this->modules[$name] = $object;
 550                 }
 551
 552                 return $this->modules[$name];
 553         }
 554
 555         /**
 556          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 557          *
 558          * @param string $name Module name
 559          * @return bool
 560          */
 561         protected function isFileModule( $name ) {
 562                 if ( !isset( $this->moduleInfos[$name] ) ) {
 563                         return false;
 564                 }
 565                 $info = $this->moduleInfos[$name];
 566                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 567                         return false;
 568                 }
 569                 return true;
 570         }
 571
 572         /**
 573          * Get the list of sources.
 574          *
 575          * @return array Like array( id => load.php url, .. )
 576          */
 577         public function getSources() {
 578                 return $this->sources;
 579         }
 580
 581         /**
 582          * Get the URL to the load.php endpoint for the given
 583          * ResourceLoader source
 584          *
 585          * @since 1.24
 586          * @param string $source
 587          * @throws MWException On an invalid $source name
 588          * @return string
 589          */
 590         public function getLoadScript( $source ) {
 591                 if ( !isset( $this->sources[$source] ) ) {
 592                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 593                 }
 594                 return $this->sources[$source];
 595         }
 596
 597         /**
 598          * @since 1.26
 599          * @param string $value
 600          * @return string Hash
 601          */
 602         public static function makeHash( $value ) {
 603                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 604                 // The first 8 chars of a base64 encoded digest represent the same binary as
 605                 // the first 12 chars of a hex encoded digest.
 606                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 607         }
 608
 609         /**
 610          * Helper method to get and combine versions of multiple modules.
 611          *
 612          * @since 1.26
 613          * @param ResourceLoaderContext $context
 614          * @param array $modules List of ResourceLoaderModule objects
 615          * @return string Hash
 616          */
 617         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 618                 if ( !$modules ) {
 619                         return '';
 620                 }
 621                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 622                 // http://php.net/functions.anonymous
 623                 $rl = $this;
 624                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 625                         return $rl->getModule( $module )->getVersionHash( $context );
 626                 }, $modules );
 627                 return self::makeHash( implode( $hashes ) );
 628         }
 629
 630         /**
 631          * Output a response to a load request, including the content-type header.
 632          *
 633          * @param ResourceLoaderContext $context Context in which a response should be formed
 634          */
 635         public function respond( ResourceLoaderContext $context ) {
 636                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 637                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 638                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 639                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 640                 // the whole thing in our own output buffer to be sure the active buffer
 641                 // doesn't use ob_gzhandler.
 642                 // See http://bugs.php.net/bug.php?id=36514
 643                 ob_start();
 644
 645                 // Find out which modules are missing and instantiate the others
 646                 $modules = array();
 647                 $missing = array();
 648                 foreach ( $context->getModules() as $name ) {
 649                         $module = $this->getModule( $name );
 650                         if ( $module ) {
 651                                 // Do not allow private modules to be loaded from the web.
 652                                 // This is a security issue, see bug 34907.
 653                                 if ( $module->getGroup() === 'private' ) {
 654                                         $this->logger->debug( "Request for private module '$name' denied" );
 655                                         $this->errors[] = "Cannot show private module \"$name\"";
 656                                         continue;
 657                                 }
 658                                 $modules[$name] = $module;
 659                         } else {
 660                                 $missing[] = $name;
 661                         }
 662                 }
 663
 664                 try {
 665                         // Preload for getCombinedVersion() and for batch makeModuleResponse()
 666                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 667                 } catch ( Exception $e ) {
 668                         MWExceptionHandler::logException( $e );
 669                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 670                                 'exception' => $e
 671                         ) );
 672                         $this->errors[] = self::formatExceptionNoComment( $e );
 673                 }
 674
 675                 // Combine versions to propagate cache invalidation
 676                 $versionHash = '';
 677                 try {
 678                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 679                 } catch ( Exception $e ) {
 680                         MWExceptionHandler::logException( $e );
 681                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 682                                 'exception' => $e
 683                         ) );
 684                         $this->errors[] = self::formatExceptionNoComment( $e );
 685                 }
 686
 687                 // See RFC 2616 § 3.11 Entity Tags
 688                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 689                 $etag = 'W/"' . $versionHash . '"';
 690
 691                 // Try the client-side cache first
 692                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 693                         return; // output handled (buffers cleared)
 694                 }
 695
 696                 // Use file cache if enabled and available...
 697                 if ( $this->config->get( 'UseFileCache' ) ) {
 698                         $fileCache = ResourceFileCache::newFromContext( $context );
 699                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 700                                 return; // output handled
 701                         }
 702                 }
 703
 704                 // Generate a response
 705                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 706
 707                 // Capture any PHP warnings from the output buffer and append them to the
 708                 // error list if we're in debug mode.
 709                 if ( $context->getDebug() ) {
 710                         $warnings = ob_get_contents();
 711                         if ( strlen( $warnings ) ) {
 712                                 $this->errors[] = $warnings;
 713                         }
 714                 }
 715
 716                 // Save response to file cache unless there are errors
 717                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 718                         // Cache single modules and images...and other requests if there are enough hits
 719                         if ( ResourceFileCache::useFileCache( $context ) ) {
 720                                 if ( $fileCache->isCacheWorthy() ) {
 721                                         $fileCache->saveText( $response );
 722                                 } else {
 723                                         $fileCache->incrMissesRecent( $context->getRequest() );
 724                                 }
 725                         }
 726                 }
 727
 728                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 729
 730                 // Remove the output buffer and output the response
 731                 ob_end_clean();
 732
 733                 if ( $context->getImageObj() && $this->errors ) {
 734                         // We can't show both the error messages and the response when it's an image.
 735                         $response = implode( "\n\n", $this->errors );
 736                 } elseif ( $this->errors ) {
 737                         $errorText = implode( "\n\n", $this->errors );
 738                         $errorResponse = self::makeComment( $errorText );
 739                         if ( $context->shouldIncludeScripts() ) {
 740                                 $errorResponse .= 'if (window.console && console.error) {'
 741                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 742                                         . "}\n";
 743                         }
 744
 745                         // Prepend error info to the response
 746                         $response = $errorResponse . $response;
 747                 }
 748
 749                 $this->errors = array();
 750                 echo $response;
 751
 752         }
 753
 754         /**
 755          * Send main response headers to the client.
 756          *
 757          * Deals with Content-Type, CORS (for stylesheets), and caching.
 758          *
 759          * @param ResourceLoaderContext $context
 760          * @param string $etag ETag header value
 761          * @param bool $errors Whether there are errors in the response
 762          * @return void
 763          */
 764         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 765                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 766                 // If a version wasn't specified we need a shorter expiry time for updates
 767                 // to propagate to clients quickly
 768                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 769                 if ( is_null( $context->getVersion() ) || $errors ) {
 770                         $maxage = $rlMaxage['unversioned']['client'];
 771                         $smaxage = $rlMaxage['unversioned']['server'];
 772                 // If a version was specified we can use a longer expiry time since changing
 773                 // version numbers causes cache misses
 774                 } else {
 775                         $maxage = $rlMaxage['versioned']['client'];
 776                         $smaxage = $rlMaxage['versioned']['server'];
 777                 }
 778                 if ( $context->getImageObj() ) {
 779                         // Output different headers if we're outputting textual errors.
 780                         if ( $errors ) {
 781                                 header( 'Content-Type: text/plain; charset=utf-8' );
 782                         } else {
 783                                 $context->getImageObj()->sendResponseHeaders( $context );
 784                         }
 785                 } elseif ( $context->getOnly() === 'styles' ) {
 786                         header( 'Content-Type: text/css; charset=utf-8' );
 787                         header( 'Access-Control-Allow-Origin: *' );
 788                 } else {
 789                         header( 'Content-Type: text/javascript; charset=utf-8' );
 790                 }
 791                 // See RFC 2616 § 14.19 ETag
 792                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 793                 header( 'ETag: ' . $etag );
 794                 if ( $context->getDebug() ) {
 795                         // Do not cache debug responses
 796                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 797                         header( 'Pragma: no-cache' );
 798                 } else {
 799                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 800                         $exp = min( $maxage, $smaxage );
 801                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 802                 }
 803         }
 804
 805         /**
 806          * Respond with HTTP 304 Not Modified if appropiate.
 807          *
 808          * If there's an If-None-Match header, respond with a 304 appropriately
 809          * and clear out the output buffer. If the client cache is too old then do nothing.
 810          *
 811          * @param ResourceLoaderContext $context
 812          * @param string $etag ETag header value
 813          * @return bool True if HTTP 304 was sent and output handled
 814          */
 815         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 816                 // See RFC 2616 § 14.26 If-None-Match
 817                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 818                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 819                 // Never send 304s in debug mode
 820                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 821                         // There's another bug in ob_gzhandler (see also the comment at
 822                         // the top of this function) that causes it to gzip even empty
 823                         // responses, meaning it's impossible to produce a truly empty
 824                         // response (because the gzip header is always there). This is
 825                         // a problem because 304 responses have to be completely empty
 826                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 827                         // See also http://bugs.php.net/bug.php?id=51579
 828                         // To work around this, we tear down all output buffering before
 829                         // sending the 304.
 830                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 831
 832                         HttpStatus::header( 304 );
 833
 834                         $this->sendResponseHeaders( $context, $etag, false );
 835                         return true;
 836                 }
 837                 return false;
 838         }
 839
 840         /**
 841          * Send out code for a response from file cache if possible.
 842          *
 843          * @param ResourceFileCache $fileCache Cache object for this request URL
 844          * @param ResourceLoaderContext $context Context in which to generate a response
 845          * @param string $etag ETag header value
 846          * @return bool If this found a cache file and handled the response
 847          */
 848         protected function tryRespondFromFileCache(
 849                 ResourceFileCache $fileCache,
 850                 ResourceLoaderContext $context,
 851                 $etag
 852         ) {
 853                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 854                 // Buffer output to catch warnings.
 855                 ob_start();
 856                 // Get the maximum age the cache can be
 857                 $maxage = is_null( $context->getVersion() )
 858                         ? $rlMaxage['unversioned']['server']
 859                         : $rlMaxage['versioned']['server'];
 860                 // Minimum timestamp the cache file must have
 861                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 862                 if ( !$good ) {
 863                         try { // RL always hits the DB on file cache miss...
 864                                 wfGetDB( DB_SLAVE );
 865                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 866                                 $good = $fileCache->isCacheGood(); // cache existence check
 867                         }
 868                 }
 869                 if ( $good ) {
 870                         $ts = $fileCache->cacheTimestamp();
 871                         // Send content type and cache headers
 872                         $this->sendResponseHeaders( $context, $etag, false );
 873                         $response = $fileCache->fetchText();
 874                         // Capture any PHP warnings from the output buffer and append them to the
 875                         // response in a comment if we're in debug mode.
 876                         if ( $context->getDebug() ) {
 877                                 $warnings = ob_get_contents();
 878                                 if ( strlen( $warnings ) ) {
 879                                         $response = self::makeComment( $warnings ) . $response;
 880                                 }
 881                         }
 882                         // Remove the output buffer and output the response
 883                         ob_end_clean();
 884                         echo $response . "\n/* Cached {$ts} */";
 885                         return true; // cache hit
 886                 }
 887                 // Clear buffer
 888                 ob_end_clean();
 889
 890                 return false; // cache miss
 891         }
 892
 893         /**
 894          * Generate a CSS or JS comment block.
 895          *
 896          * Only use this for public data, not error message details.
 897          *
 898          * @param string $text
 899          * @return string
 900          */
 901         public static function makeComment( $text ) {
 902                 $encText = str_replace( '*/', '* /', $text );
 903                 return "/*\n$encText\n*/\n";
 904         }
 905
 906         /**
 907          * Handle exception display.
 908          *
 909          * @param Exception $e Exception to be shown to the user
 910          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 911          */
 912         public static function formatException( $e ) {
 913                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 914         }
 915
 916         /**
 917          * Handle exception display.
 918          *
 919          * @since 1.25
 920          * @param Exception $e Exception to be shown to the user
 921          * @return string Sanitized text that can be returned to the user
 922          */
 923         protected static function formatExceptionNoComment( $e ) {
 924                 global $wgShowExceptionDetails;
 925
 926                 if ( !$wgShowExceptionDetails ) {
 927                         return MWExceptionHandler::getPublicLogMessage( $e );
 928                 }
 929
 930                 return MWExceptionHandler::getLogMessage( $e );
 931         }
 932
 933         /**
 934          * Generate code for a response.
 935          *
 936          * @param ResourceLoaderContext $context Context in which to generate a response
 937          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 938          * @param string[] $missing List of requested module names that are unregistered (optional)
 939          * @return string Response data
 940          */
 941         public function makeModuleResponse( ResourceLoaderContext $context,
 942                 array $modules, array $missing = array()
 943         ) {
 944                 $out = '';
 945                 $states = array();
 946
 947                 if ( !count( $modules ) && !count( $missing ) ) {
 948                         return <<<MESSAGE
 949 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 950    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 951    no modules were requested. Max made me put this here. */
 952 MESSAGE;
 953                 }
 954
 955                 $image = $context->getImageObj();
 956                 if ( $image ) {
 957                         $data = $image->getImageData( $context );
 958                         if ( $data === false ) {
 959                                 $data = '';
 960                                 $this->errors[] = 'Image generation failed';
 961                         }
 962                         return $data;
 963                 }
 964
 965                 foreach ( $missing as $name ) {
 966                         $states[$name] = 'missing';
 967                 }
 968
 969                 // Generate output
 970                 $isRaw = false;
 971
 972                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
 973
 974                 foreach ( $modules as $name => $module ) {
 975                         try {
 976                                 $content = $module->getModuleContent( $context );
 977                                 $strContent = '';
 978
 979                                 // Append output
 980                                 switch ( $context->getOnly() ) {
 981                                         case 'scripts':
 982                                                 $scripts = $content['scripts'];
 983                                                 if ( is_string( $scripts ) ) {
 984                                                         // Load scripts raw...
 985                                                         $strContent = $scripts;
 986                                                 } elseif ( is_array( $scripts ) ) {
 987                                                         // ...except when $scripts is an array of URLs
 988                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
 989                                                 }
 990                                                 break;
 991                                         case 'styles':
 992                                                 $styles = $content['styles'];
 993                                                 // We no longer seperate into media, they are all combined now with
 994                                                 // custom media type groups into @media .. {} sections as part of the css string.
 995                                                 // Module returns either an empty array or a numerical array with css strings.
 996                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 997                                                 break;
 998                                         default:
 999                                                 $strContent = self::makeLoaderImplementScript(
1000                                                         $name,
1001                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1002                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1003                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1004                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1005                                                 );
1006                                                 break;
1007                                 }
1008
1009                                 if ( !$context->getDebug() ) {
1010                                         $strContent = self::filter( $filter, $strContent );
1011                                 }
1012
1013                                 $out .= $strContent;
1014
1015                         } catch ( Exception $e ) {
1016                                 MWExceptionHandler::logException( $e );
1017                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1018                                         'exception' => $e
1019                                 ) );
1020                                 $this->errors[] = self::formatExceptionNoComment( $e );
1021
1022                                 // Respond to client with error-state instead of module implementation
1023                                 $states[$name] = 'error';
1024                                 unset( $modules[$name] );
1025                         }
1026                         $isRaw |= $module->isRaw();
1027                 }
1028
1029                 // Update module states
1030                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1031                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1032                                 // Set the state of modules loaded as only scripts to ready as
1033                                 // they don't have an mw.loader.implement wrapper that sets the state
1034                                 foreach ( $modules as $name => $module ) {
1035                                         $states[$name] = 'ready';
1036                                 }
1037                         }
1038
1039                         // Set the state of modules we didn't respond to with mw.loader.implement
1040                         if ( count( $states ) ) {
1041                                 $stateScript = self::makeLoaderStateScript( $states );
1042                                 if ( !$context->getDebug() ) {
1043                                         $stateScript = self::filter( 'minify-js', $stateScript );
1044                                 }
1045                                 $out .= $stateScript;
1046                         }
1047                 } else {
1048                         if ( count( $states ) ) {
1049                                 $this->errors[] = 'Problematic modules: ' .
1050                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1051                         }
1052                 }
1053
1054                 return $out;
1055         }
1056
1057         /**
1058          * Get names of modules that use a certain message.
1059          *
1060          * @param string $messageKey
1061          * @return array List of module names
1062          */
1063         public function getModulesByMessage( $messageKey ) {
1064                 $moduleNames = array();
1065                 foreach ( $this->getModuleNames() as $moduleName ) {
1066                         $module = $this->getModule( $moduleName );
1067                         if ( in_array( $messageKey, $module->getMessages() ) ) {
1068                                 $moduleNames[] = $moduleName;
1069                         }
1070                 }
1071                 return $moduleNames;
1072         }
1073
1074         /* Static Methods */
1075
1076         /**
1077          * Return JS code that calls mw.loader.implement with given module properties.
1078          *
1079          * @param string $name Module name
1080          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1081          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1082          *   to CSS files keyed by media type
1083          * @param mixed $messages List of messages associated with this module. May either be an
1084          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1085          *   the same data, wrapped in an XmlJsCode object.
1086          * @param array $templates Keys are name of templates and values are the source of
1087          *   the template.
1088          * @throws MWException
1089          * @return string
1090          */
1091         public static function makeLoaderImplementScript(
1092                 $name, $scripts, $styles, $messages, $templates
1093         ) {
1094                 if ( is_string( $scripts ) ) {
1095                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1096                         // Transportation as string instructs mw.loader.implement to use globalEval.
1097                         if ( $name === 'site' || $name === 'user' ) {
1098                                 // Minify manually because the general makeModuleResponse() minification won't be
1099                                 // effective here due to the script being a string instead of a function. (T107377)
1100                                 if ( !ResourceLoader::inDebugMode() ) {
1101                                         $scripts = self::filter( 'minify-js', $scripts );
1102                                 }
1103                         } else {
1104                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1105                         }
1106                 } elseif ( !is_array( $scripts ) ) {
1107                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1108                 }
1109                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1110                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1111                 // of "{}". Force them to objects.
1112                 $module = array(
1113                         $name,
1114                         $scripts,
1115                         (object)$styles,
1116                         (object)$messages,
1117                         (object)$templates,
1118                 );
1119                 self::trimArray( $module );
1120
1121                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1122         }
1123
1124         /**
1125          * Returns JS code which, when called, will register a given list of messages.
1126          *
1127          * @param mixed $messages Either an associative array mapping message key to value, or a
1128          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1129          * @return string
1130          */
1131         public static function makeMessageSetScript( $messages ) {
1132                 return Xml::encodeJsCall(
1133                         'mw.messages.set',
1134                         array( (object)$messages ),
1135                         ResourceLoader::inDebugMode()
1136                 );
1137         }
1138
1139         /**
1140          * Combines an associative array mapping media type to CSS into a
1141          * single stylesheet with "@media" blocks.
1142          *
1143          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1144          * @return array
1145          */
1146         public static function makeCombinedStyles( array $stylePairs ) {
1147                 $out = array();
1148                 foreach ( $stylePairs as $media => $styles ) {
1149                         // ResourceLoaderFileModule::getStyle can return the styles
1150                         // as a string or an array of strings. This is to allow separation in
1151                         // the front-end.
1152                         $styles = (array)$styles;
1153                         foreach ( $styles as $style ) {
1154                                 $style = trim( $style );
1155                                 // Don't output an empty "@media print { }" block (bug 40498)
1156                                 if ( $style !== '' ) {
1157                                         // Transform the media type based on request params and config
1158                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1159                                         $media = OutputPage::transformCssMedia( $media );
1160
1161                                         if ( $media === '' || $media == 'all' ) {
1162                                                 $out[] = $style;
1163                                         } elseif ( is_string( $media ) ) {
1164                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1165                                         }
1166                                         // else: skip
1167                                 }
1168                         }
1169                 }
1170                 return $out;
1171         }
1172
1173         /**
1174          * Returns a JS call to mw.loader.state, which sets the state of a
1175          * module or modules to a given value. Has two calling conventions:
1176          *
1177          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1178          *         Set the state of a single module called $name to $state
1179          *
1180          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1181          *         Set the state of modules with the given names to the given states
1182          *
1183          * @param string $name
1184          * @param string $state
1185          * @return string
1186          */
1187         public static function makeLoaderStateScript( $name, $state = null ) {
1188                 if ( is_array( $name ) ) {
1189                         return Xml::encodeJsCall(
1190                                 'mw.loader.state',
1191                                 array( $name ),
1192                                 ResourceLoader::inDebugMode()
1193                         );
1194                 } else {
1195                         return Xml::encodeJsCall(
1196                                 'mw.loader.state',
1197                                 array( $name, $state ),
1198                                 ResourceLoader::inDebugMode()
1199                         );
1200                 }
1201         }
1202
1203         /**
1204          * Returns JS code which calls the script given by $script. The script will
1205          * be called with local variables name, version, dependencies and group,
1206          * which will have values corresponding to $name, $version, $dependencies
1207          * and $group as supplied.
1208          *
1209          * @param string $name Module name
1210          * @param string $version Module version hash
1211          * @param array $dependencies List of module names on which this module depends
1212          * @param string $group Group which the module is in.
1213          * @param string $source Source of the module, or 'local' if not foreign.
1214          * @param string $script JavaScript code
1215          * @return string
1216          */
1217         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1218                 $group, $source, $script
1219         ) {
1220                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1221                 return Xml::encodeJsCall(
1222                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1223                         array( $name, $version, $dependencies, $group, $source ),
1224                         ResourceLoader::inDebugMode()
1225                 );
1226         }
1227
1228         private static function isEmptyObject( stdClass $obj ) {
1229                 foreach ( $obj as $key => $value ) {
1230                         return false;
1231                 }
1232                 return true;
1233         }
1234
1235         /**
1236          * Remove empty values from the end of an array.
1237          *
1238          * Values considered empty:
1239          *
1240          * - null
1241          * - array()
1242          * - new XmlJsCode( '{}' )
1243          * - new stdClass() // (object) array()
1244          *
1245          * @param Array $array
1246          */
1247         private static function trimArray( Array &$array ) {
1248                 $i = count( $array );
1249                 while ( $i-- ) {
1250                         if ( $array[$i] === null
1251                                 || $array[$i] === array()
1252                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1253                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1254                         ) {
1255                                 unset( $array[$i] );
1256                         } else {
1257                                 break;
1258                         }
1259                 }
1260         }
1261
1262         /**
1263          * Returns JS code which calls mw.loader.register with the given
1264          * parameters. Has three calling conventions:
1265          *
1266          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1267          *        $dependencies, $group, $source, $skip
1268          *     ):
1269          *        Register a single module.
1270          *
1271          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1272          *        Register modules with the given names.
1273          *
1274          *   - ResourceLoader::makeLoaderRegisterScript( array(
1275          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1276          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1277          *        ...
1278          *     ) ):
1279          *        Registers modules with the given names and parameters.
1280          *
1281          * @param string $name Module name
1282          * @param string $version Module version hash
1283          * @param array $dependencies List of module names on which this module depends
1284          * @param string $group Group which the module is in
1285          * @param string $source Source of the module, or 'local' if not foreign
1286          * @param string $skip Script body of the skip function
1287          * @return string
1288          */
1289         public static function makeLoaderRegisterScript( $name, $version = null,
1290                 $dependencies = null, $group = null, $source = null, $skip = null
1291         ) {
1292                 if ( is_array( $name ) ) {
1293                         // Build module name index
1294                         $index = array();
1295                         foreach ( $name as $i => &$module ) {
1296                                 $index[$module[0]] = $i;
1297                         }
1298
1299                         // Transform dependency names into indexes when possible, they will be resolved by
1300                         // mw.loader.register on the other end
1301                         foreach ( $name as &$module ) {
1302                                 if ( isset( $module[2] ) ) {
1303                                         foreach ( $module[2] as &$dependency ) {
1304                                                 if ( isset( $index[$dependency] ) ) {
1305                                                         $dependency = $index[$dependency];
1306                                                 }
1307                                         }
1308                                 }
1309                         }
1310
1311                         array_walk( $name, array( 'self', 'trimArray' ) );
1312
1313                         return Xml::encodeJsCall(
1314                                 'mw.loader.register',
1315                                 array( $name ),
1316                                 ResourceLoader::inDebugMode()
1317                         );
1318                 } else {
1319                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1320                         self::trimArray( $registration );
1321                         return Xml::encodeJsCall(
1322                                 'mw.loader.register',
1323                                 $registration,
1324                                 ResourceLoader::inDebugMode()
1325                         );
1326                 }
1327         }
1328
1329         /**
1330          * Returns JS code which calls mw.loader.addSource() with the given
1331          * parameters. Has two calling conventions:
1332          *
1333          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1334          *       Register a single source
1335          *
1336          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1337          *       Register sources with the given IDs and properties.
1338          *
1339          * @param string $id Source ID
1340          * @param array $properties Source properties (see addSource())
1341          * @return string
1342          */
1343         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1344                 if ( is_array( $id ) ) {
1345                         return Xml::encodeJsCall(
1346                                 'mw.loader.addSource',
1347                                 array( $id ),
1348                                 ResourceLoader::inDebugMode()
1349                         );
1350                 } else {
1351                         return Xml::encodeJsCall(
1352                                 'mw.loader.addSource',
1353                                 array( $id, $properties ),
1354                                 ResourceLoader::inDebugMode()
1355                         );
1356                 }
1357         }
1358
1359         /**
1360          * Returns JS code which runs given JS code if the client-side framework is
1361          * present.
1362          *
1363          * @deprecated since 1.25; use makeInlineScript instead
1364          * @param string $script JavaScript code
1365          * @return string
1366          */
1367         public static function makeLoaderConditionalScript( $script ) {
1368                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1369                         trim( $script ) . "\n} );";
1370         }
1371
1372         /**
1373          * Construct an inline script tag with given JS code.
1374          *
1375          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1376          * only if the client has adequate support for MediaWiki JavaScript code.
1377          *
1378          * @param string $script JavaScript code
1379          * @return WrappedString HTML
1380          */
1381         public static function makeInlineScript( $script ) {
1382                 $js = self::makeLoaderConditionalScript( $script );
1383                 return new WrappedString(
1384                         Html::inlineScript( $js ),
1385                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1386                         "\n} );</script>"
1387                 );
1388         }
1389
1390         /**
1391          * Returns JS code which will set the MediaWiki configuration array to
1392          * the given value.
1393          *
1394          * @param array $configuration List of configuration values keyed by variable name
1395          * @return string
1396          */
1397         public static function makeConfigSetScript( array $configuration ) {
1398                 return Xml::encodeJsCall(
1399                         'mw.config.set',
1400                         array( $configuration ),
1401                         ResourceLoader::inDebugMode()
1402                 ) . ResourceLoader::FILTER_NOMIN;
1403         }
1404
1405         /**
1406          * Convert an array of module names to a packed query string.
1407          *
1408          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1409          * becomes 'foo.bar,baz|bar.baz,quux'
1410          * @param array $modules List of module names (strings)
1411          * @return string Packed query string
1412          */
1413         public static function makePackedModulesString( $modules ) {
1414                 $groups = array(); // array( prefix => array( suffixes ) )
1415                 foreach ( $modules as $module ) {
1416                         $pos = strrpos( $module, '.' );
1417                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1418                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1419                         $groups[$prefix][] = $suffix;
1420                 }
1421
1422                 $arr = array();
1423                 foreach ( $groups as $prefix => $suffixes ) {
1424                         $p = $prefix === '' ? '' : $prefix . '.';
1425                         $arr[] = $p . implode( ',', $suffixes );
1426                 }
1427                 $str = implode( '|', $arr );
1428                 return $str;
1429         }
1430
1431         /**
1432          * Determine whether debug mode was requested
1433          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1434          * @return bool
1435          */
1436         public static function inDebugMode() {
1437                 if ( self::$debugMode === null ) {
1438                         global $wgRequest, $wgResourceLoaderDebug;
1439                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1440                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1441                         );
1442                 }
1443                 return self::$debugMode;
1444         }
1445
1446         /**
1447          * Reset static members used for caching.
1448          *
1449          * Global state and $wgRequest are evil, but we're using it right
1450          * now and sometimes we need to be able to force ResourceLoader to
1451          * re-evaluate the context because it has changed (e.g. in the test suite).
1452          */
1453         public static function clearCache() {
1454                 self::$debugMode = null;
1455         }
1456
1457         /**
1458          * Build a load.php URL
1459          *
1460          * @since 1.24
1461          * @param string $source Name of the ResourceLoader source
1462          * @param ResourceLoaderContext $context
1463          * @param array $extraQuery
1464          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1465          */
1466         public function createLoaderURL( $source, ResourceLoaderContext $context,
1467                 $extraQuery = array()
1468         ) {
1469                 $query = self::createLoaderQuery( $context, $extraQuery );
1470                 $script = $this->getLoadScript( $source );
1471
1472                 return wfAppendQuery( $script, $query );
1473         }
1474
1475         /**
1476          * Build a load.php URL
1477          * @deprecated since 1.24 Use createLoaderURL() instead
1478          * @param array $modules Array of module names (strings)
1479          * @param string $lang Language code
1480          * @param string $skin Skin name
1481          * @param string|null $user User name. If null, the &user= parameter is omitted
1482          * @param string|null $version Versioning timestamp
1483          * @param bool $debug Whether the request should be in debug mode
1484          * @param string|null $only &only= parameter
1485          * @param bool $printable Printable mode
1486          * @param bool $handheld Handheld mode
1487          * @param array $extraQuery Extra query parameters to add
1488          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1489          */
1490         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1491                 $version = null, $debug = false, $only = null, $printable = false,
1492                 $handheld = false, $extraQuery = array()
1493         ) {
1494                 global $wgLoadScript;
1495
1496                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1497                         $only, $printable, $handheld, $extraQuery
1498                 );
1499
1500                 return wfAppendQuery( $wgLoadScript, $query );
1501         }
1502
1503         /**
1504          * Helper for createLoaderURL()
1505          *
1506          * @since 1.24
1507          * @see makeLoaderQuery
1508          * @param ResourceLoaderContext $context
1509          * @param array $extraQuery
1510          * @return array
1511          */
1512         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1513                 return self::makeLoaderQuery(
1514                         $context->getModules(),
1515                         $context->getLanguage(),
1516                         $context->getSkin(),
1517                         $context->getUser(),
1518                         $context->getVersion(),
1519                         $context->getDebug(),
1520                         $context->getOnly(),
1521                         $context->getRequest()->getBool( 'printable' ),
1522                         $context->getRequest()->getBool( 'handheld' ),
1523                         $extraQuery
1524                 );
1525         }
1526
1527         /**
1528          * Build a query array (array representation of query string) for load.php. Helper
1529          * function for makeLoaderURL().
1530          *
1531          * @param array $modules
1532          * @param string $lang
1533          * @param string $skin
1534          * @param string $user
1535          * @param string $version
1536          * @param bool $debug
1537          * @param string $only
1538          * @param bool $printable
1539          * @param bool $handheld
1540          * @param array $extraQuery
1541          *
1542          * @return array
1543          */
1544         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1545                 $version = null, $debug = false, $only = null, $printable = false,
1546                 $handheld = false, $extraQuery = array()
1547         ) {
1548                 $query = array(
1549                         'modules' => self::makePackedModulesString( $modules ),
1550                         'lang' => $lang,
1551                         'skin' => $skin,
1552                         'debug' => $debug ? 'true' : 'false',
1553                 );
1554                 if ( $user !== null ) {
1555                         $query['user'] = $user;
1556                 }
1557                 if ( $version !== null ) {
1558                         $query['version'] = $version;
1559                 }
1560                 if ( $only !== null ) {
1561                         $query['only'] = $only;
1562                 }
1563                 if ( $printable ) {
1564                         $query['printable'] = 1;
1565                 }
1566                 if ( $handheld ) {
1567                         $query['handheld'] = 1;
1568                 }
1569                 $query += $extraQuery;
1570
1571                 // Make queries uniform in order
1572                 ksort( $query );
1573                 return $query;
1574         }
1575
1576         /**
1577          * Check a module name for validity.
1578          *
1579          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1580          * at most 255 bytes.
1581          *
1582          * @param string $moduleName Module name to check
1583          * @return bool Whether $moduleName is a valid module name
1584          */
1585         public static function isValidModuleName( $moduleName ) {
1586                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1587         }
1588
1589         /**
1590          * Returns LESS compiler set up for use with MediaWiki
1591          *
1592          * @since 1.27
1593          * @param array $extraVars Associative array of extra (i.e., other than the
1594          *   globally-configured ones) that should be used for compilation.
1595          * @throws MWException
1596          * @return Less_Parser
1597          */
1598         public function getLessCompiler( $extraVars = array() ) {
1599                 // When called from the installer, it is possible that a required PHP extension
1600                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1601                 // exception (caught by the installer) to prevent a fatal error later on.
1602                 if ( !class_exists( 'Less_Parser' ) ) {
1603                         throw new MWException( 'MediaWiki requires the less.php parser' );
1604                 }
1605
1606                 $parser = new Less_Parser;
1607                 $parser->ModifyVars( array_merge( $this->getLessVars(), $extraVars ) );
1608                 $parser->SetImportDirs(
1609                         array_fill_keys( $this->config->get( 'ResourceLoaderLESSImportPaths' ), '' )
1610                 );
1611                 $parser->SetOption( 'relativeUrls', false );
1612                 $parser->SetCacheDir( $this->config->get( 'CacheDirectory' ) ?: wfTempDir() );
1613
1614                 return $parser;
1615         }
1616
1617         /**
1618          * Get global LESS variables.
1619          *
1620          * @since 1.27
1621          * @return array Map of variable names to string CSS values.
1622          */
1623         public function getLessVars() {
1624                 if ( !$this->lessVars ) {
1625                         $lessVars = $this->config->get( 'ResourceLoaderLESSVars' );
1626                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1627                         $this->lessVars = $lessVars;
1628                 }
1629                 return $this->lessVars;
1630         }
1631 }