includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 use Psr\Log\LoggerAwareInterface;
  26 use Psr\Log\LoggerInterface;
  27 use Psr\Log\NullLogger;
  28 use WrappedString\WrappedString;
  29
  30 /**
  31  * Dynamic JavaScript and CSS resource loading system.
  32  *
  33  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  34  *    https://www.mediawiki.org/wiki/ResourceLoader
  35  */
  36 class ResourceLoader implements LoggerAwareInterface {
  37         /** @var int */
  38         protected static $filterCacheVersion = 7;
  39
  40         /** @var bool */
  41         protected static $debugMode = null;
  42
  43         /** @var array */
  44         private static $lessVars = null;
  45
  46         /**
  47          * Module name/ResourceLoaderModule object pairs
  48          * @var array
  49          */
  50         protected $modules = array();
  51
  52         /**
  53          * Associative array mapping module name to info associative array
  54          * @var array
  55          */
  56         protected $moduleInfos = array();
  57
  58         /** @var Config $config */
  59         private $config;
  60
  61         /**
  62          * Associative array mapping framework ids to a list of names of test suite modules
  63          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  64          * @var array
  65          */
  66         protected $testModuleNames = array();
  67
  68         /**
  69          * E.g. array( 'source-id' => 'http://.../load.php' )
  70          * @var array
  71          */
  72         protected $sources = array();
  73
  74         /**
  75          * Errors accumulated during current respond() call.
  76          * @var array
  77          */
  78         protected $errors = array();
  79
  80         /**
  81          * @var MessageBlobStore
  82          */
  83         protected $blobStore;
  84
  85         /**
  86          * @var LoggerInterface
  87          */
  88         private $logger;
  89
  90         /** @var string JavaScript / CSS pragma to disable minification. **/
  91         const FILTER_NOMIN = ' /* @nomin */ ';
  92
  93         /**
  94          * Load information stored in the database about modules.
  95          *
  96          * This method grabs modules dependencies from the database and updates modules
  97          * objects.
  98          *
  99          * This is not inside the module code because it is much faster to
 100          * request all of the information at once than it is to have each module
 101          * requests its own information. This sacrifice of modularity yields a substantial
 102          * performance improvement.
 103          *
 104          * @param array $modules List of module names to preload information for
 105          * @param ResourceLoaderContext $context Context to load the information within
 106          */
 107         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
 108                 if ( !count( $modules ) ) {
 109                         // Or else Database*::select() will explode, plus it's cheaper!
 110                         return;
 111                 }
 112                 $dbr = wfGetDB( DB_SLAVE );
 113                 $skin = $context->getSkin();
 114                 $lang = $context->getLanguage();
 115
 116                 // Batched version of ResourceLoaderModule::getFileDependencies
 117                 $vary = "$skin|$lang";
 118                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 119                                 'md_module' => $modules,
 120                                 'md_skin' => $vary,
 121                         ), __METHOD__
 122                 );
 123                 // Prime in-object cache values for each module
 124                 $modulesWithDeps = array();
 125                 foreach ( $res as $row ) {
 126                         $module = $this->getModule( $row->md_module );
 127                         if ( $module ) {
 128                                 $module->setFileDependencies( $context, ResourceLoaderModule::expandRelativePaths(
 129                                         FormatJson::decode( $row->md_deps, true )
 130                                 ) );
 131                                 $modulesWithDeps[] = $row->md_module;
 132                         }
 133                 }
 134                 // Register the absence of a dependency row too
 135                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 136                         $module = $this->getModule( $name );
 137                         if ( $module ) {
 138                                 $this->getModule( $name )->setFileDependencies( $context, array() );
 139                         }
 140                 }
 141
 142                 // Get message blob mtimes. Only do this for modules with messages
 143                 $modulesWithMessages = array();
 144                 foreach ( $modules as $name ) {
 145                         $module = $this->getModule( $name );
 146                         if ( $module && count( $module->getMessages() ) ) {
 147                                 $modulesWithMessages[] = $name;
 148                         }
 149                 }
 150                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 151                 if ( count( $modulesWithMessages ) ) {
 152                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 153                                         'mr_resource' => $modulesWithMessages,
 154                                         'mr_lang' => $lang
 155                                 ), __METHOD__
 156                         );
 157                         foreach ( $res as $row ) {
 158                                 $module = $this->getModule( $row->mr_resource );
 159                                 if ( $module ) {
 160                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 161                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 162                                 }
 163                         }
 164                 }
 165                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 166                         $module = $this->getModule( $name );
 167                         if ( $module ) {
 168                                 $module->setMsgBlobMtime( $lang, 1 );
 169                         }
 170                 }
 171         }
 172
 173         /**
 174          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 175          *
 176          * Available filters are:
 177          *
 178          *    - minify-js \see JavaScriptMinifier::minify
 179          *    - minify-css \see CSSMin::minify
 180          *
 181          * If $data is empty, only contains whitespace or the filter was unknown,
 182          * $data is returned unmodified.
 183          *
 184          * @param string $filter Name of filter to run
 185          * @param string $data Text to filter, such as JavaScript or CSS text
 186          * @param array $options Keys:
 187          *  - (bool) cache: Whether to allow caching this data. Default: true.
 188          * @return string Filtered data, or a comment containing an error message
 189          */
 190         public static function filter( $filter, $data, Array $options = array() ) {
 191                 if ( strpos( $data, ResourceLoader::FILTER_NOMIN ) !== false ) {
 192                         return $data;
 193                 }
 194
 195                 if ( isset( $options['cache'] ) && $options['cache'] === false ) {
 196                         return self::applyFilter( $filter, $data );
 197                 }
 198
 199                 $stats = RequestContext::getMain()->getStats();
 200                 $cache = ObjectCache::newAccelerator( CACHE_ANYTHING );
 201
 202                 $key = $cache->makeGlobalKey(
 203                         'resourceloader',
 204                         'filter',
 205                         $filter,
 206                         self::$filterCacheVersion, md5( $data )
 207                 );
 208
 209                 $result = $cache->get( $key );
 210                 if ( $result === false ) {
 211                         $stats->increment( "resourceloader_cache.$filter.miss" );
 212                         $result = self::applyFilter( $filter, $data );
 213                         $cache->set( $key, $result, 24 * 3600 );
 214                 } else {
 215                         $stats->increment( "resourceloader_cache.$filter.hit" );
 216                 }
 217                 if ( $result === null ) {
 218                         // Cached failure
 219                         $result = $data;
 220                 }
 221
 222                 return $result;
 223         }
 224
 225         private static function applyFilter( $filter, $data ) {
 226                 $data = trim( $data );
 227                 if ( $data ) {
 228                         try {
 229                                 $data = ( $filter === 'minify-css' )
 230                                         ? CSSMin::minify( $data )
 231                                         : JavaScriptMinifier::minify( $data );
 232                         } catch ( Exception $e ) {
 233                                 MWExceptionHandler::logException( $e );
 234                                 return null;
 235                         }
 236                 }
 237                 return $data;
 238         }
 239
 240         /* Methods */
 241
 242         /**
 243          * Register core modules and runs registration hooks.
 244          * @param Config|null $config
 245          */
 246         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 247                 global $IP;
 248
 249                 if ( !$logger ) {
 250                         $logger = new NullLogger();
 251                 }
 252                 $this->setLogger( $logger );
 253
 254                 if ( !$config ) {
 255                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 256                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 257                 }
 258                 $this->config = $config;
 259
 260                 // Add 'local' source first
 261                 $this->addSource( 'local', wfScript( 'load' ) );
 262
 263                 // Add other sources
 264                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 265
 266                 // Register core modules
 267                 $this->register( include "$IP/resources/Resources.php" );
 268                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 269                 // Register extension modules
 270                 $this->register( $config->get( 'ResourceModules' ) );
 271                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 272
 273                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 274                         $this->registerTestModules();
 275                 }
 276
 277                 $this->setMessageBlobStore( new MessageBlobStore() );
 278         }
 279
 280         /**
 281          * @return Config
 282          */
 283         public function getConfig() {
 284                 return $this->config;
 285         }
 286
 287         public function setLogger( LoggerInterface $logger ) {
 288                 $this->logger = $logger;
 289         }
 290
 291         /**
 292          * @since 1.26
 293          * @return MessageBlobStore
 294          */
 295         public function getMessageBlobStore() {
 296                 return $this->blobStore;
 297         }
 298
 299         /**
 300          * @since 1.25
 301          * @param MessageBlobStore $blobStore
 302          */
 303         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 304                 $this->blobStore = $blobStore;
 305         }
 306
 307         /**
 308          * Register a module with the ResourceLoader system.
 309          *
 310          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 311          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 312          *   this may also be a ResourceLoaderModule object. Optional when using
 313          *   multiple-registration calling style.
 314          * @throws MWException If a duplicate module registration is attempted
 315          * @throws MWException If a module name contains illegal characters (pipes or commas)
 316          * @throws MWException If something other than a ResourceLoaderModule is being registered
 317          * @return bool False if there were any errors, in which case one or more modules were
 318          *   not registered
 319          */
 320         public function register( $name, $info = null ) {
 321
 322                 // Allow multiple modules to be registered in one call
 323                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 324                 foreach ( $registrations as $name => $info ) {
 325                         // Warn on duplicate registrations
 326                         if ( isset( $this->moduleInfos[$name] ) ) {
 327                                 // A module has already been registered by this name
 328                                 $this->logger->warning(
 329                                         'ResourceLoader duplicate registration warning. ' .
 330                                         'Another module has already been registered as ' . $name
 331                                 );
 332                         }
 333
 334                         // Check $name for validity
 335                         if ( !self::isValidModuleName( $name ) ) {
 336                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 337                                         . "see ResourceLoader::isValidModuleName()" );
 338                         }
 339
 340                         // Attach module
 341                         if ( $info instanceof ResourceLoaderModule ) {
 342                                 $this->moduleInfos[$name] = array( 'object' => $info );
 343                                 $info->setName( $name );
 344                                 $this->modules[$name] = $info;
 345                         } elseif ( is_array( $info ) ) {
 346                                 // New calling convention
 347                                 $this->moduleInfos[$name] = $info;
 348                         } else {
 349                                 throw new MWException(
 350                                         'ResourceLoader module info type error for module \'' . $name .
 351                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 352                                 );
 353                         }
 354
 355                         // Last-minute changes
 356
 357                         // Apply custom skin-defined styles to existing modules.
 358                         if ( $this->isFileModule( $name ) ) {
 359                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 360                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 361                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 362                                                 continue;
 363                                         }
 364
 365                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 366                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 367                                         if ( isset( $skinStyles[$name] ) ) {
 368                                                 $paths = (array)$skinStyles[$name];
 369                                                 $styleFiles = array();
 370                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 371                                                 $paths = (array)$skinStyles['+' . $name];
 372                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 373                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 374                                                         array();
 375                                         } else {
 376                                                 continue;
 377                                         }
 378
 379                                         // Add new file paths, remapping them to refer to our directories and not use settings
 380                                         // from the module we're modifying, which come from the base definition.
 381                                         list( $localBasePath, $remoteBasePath ) =
 382                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 383
 384                                         foreach ( $paths as $path ) {
 385                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 386                                         }
 387
 388                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 389                                 }
 390                         }
 391                 }
 392
 393         }
 394
 395         /**
 396          */
 397         public function registerTestModules() {
 398                 global $IP;
 399
 400                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 401                         throw new MWException( 'Attempt to register JavaScript test modules '
 402                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 403                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 404                 }
 405
 406                 // Get core test suites
 407                 $testModules = array();
 408                 $testModules['qunit'] = array();
 409                 // Get other test suites (e.g. from extensions)
 410                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 411
 412                 // Add the testrunner (which configures QUnit) to the dependencies.
 413                 // Since it must be ready before any of the test suites are executed.
 414                 foreach ( $testModules['qunit'] as &$module ) {
 415                         // Make sure all test modules are top-loading so that when QUnit starts
 416                         // on document-ready, it will run once and finish. If some tests arrive
 417                         // later (possibly after QUnit has already finished) they will be ignored.
 418                         $module['position'] = 'top';
 419                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 420                 }
 421
 422                 $testModules['qunit'] =
 423                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 424
 425                 foreach ( $testModules as $id => $names ) {
 426                         // Register test modules
 427                         $this->register( $testModules[$id] );
 428
 429                         // Keep track of their names so that they can be loaded together
 430                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 431                 }
 432
 433         }
 434
 435         /**
 436          * Add a foreign source of modules.
 437          *
 438          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 439          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 440          *  backwards-compatibility.
 441          * @throws MWException
 442          */
 443         public function addSource( $id, $loadUrl = null ) {
 444                 // Allow multiple sources to be registered in one call
 445                 if ( is_array( $id ) ) {
 446                         foreach ( $id as $key => $value ) {
 447                                 $this->addSource( $key, $value );
 448                         }
 449                         return;
 450                 }
 451
 452                 // Disallow duplicates
 453                 if ( isset( $this->sources[$id] ) ) {
 454                         throw new MWException(
 455                                 'ResourceLoader duplicate source addition error. ' .
 456                                 'Another source has already been registered as ' . $id
 457                         );
 458                 }
 459
 460                 // Pre 1.24 backwards-compatibility
 461                 if ( is_array( $loadUrl ) ) {
 462                         if ( !isset( $loadUrl['loadScript'] ) ) {
 463                                 throw new MWException(
 464                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 465                                 );
 466                         }
 467
 468                         $loadUrl = $loadUrl['loadScript'];
 469                 }
 470
 471                 $this->sources[$id] = $loadUrl;
 472         }
 473
 474         /**
 475          * Get a list of module names.
 476          *
 477          * @return array List of module names
 478          */
 479         public function getModuleNames() {
 480                 return array_keys( $this->moduleInfos );
 481         }
 482
 483         /**
 484          * Get a list of test module names for one (or all) frameworks.
 485          *
 486          * If the given framework id is unknkown, or if the in-object variable is not an array,
 487          * then it will return an empty array.
 488          *
 489          * @param string $framework Get only the test module names for one
 490          *   particular framework (optional)
 491          * @return array
 492          */
 493         public function getTestModuleNames( $framework = 'all' ) {
 494                 /** @todo api siteinfo prop testmodulenames modulenames */
 495                 if ( $framework == 'all' ) {
 496                         return $this->testModuleNames;
 497                 } elseif ( isset( $this->testModuleNames[$framework] )
 498                         && is_array( $this->testModuleNames[$framework] )
 499                 ) {
 500                         return $this->testModuleNames[$framework];
 501                 } else {
 502                         return array();
 503                 }
 504         }
 505
 506         /**
 507          * Check whether a ResourceLoader module is registered
 508          *
 509          * @since 1.25
 510          * @param string $name
 511          * @return bool
 512          */
 513         public function isModuleRegistered( $name ) {
 514                 return isset( $this->moduleInfos[$name] );
 515         }
 516
 517         /**
 518          * Get the ResourceLoaderModule object for a given module name.
 519          *
 520          * If an array of module parameters exists but a ResourceLoaderModule object has not
 521          * yet been instantiated, this method will instantiate and cache that object such that
 522          * subsequent calls simply return the same object.
 523          *
 524          * @param string $name Module name
 525          * @return ResourceLoaderModule|null If module has been registered, return a
 526          *  ResourceLoaderModule instance. Otherwise, return null.
 527          */
 528         public function getModule( $name ) {
 529                 if ( !isset( $this->modules[$name] ) ) {
 530                         if ( !isset( $this->moduleInfos[$name] ) ) {
 531                                 // No such module
 532                                 return null;
 533                         }
 534                         // Construct the requested object
 535                         $info = $this->moduleInfos[$name];
 536                         /** @var ResourceLoaderModule $object */
 537                         if ( isset( $info['object'] ) ) {
 538                                 // Object given in info array
 539                                 $object = $info['object'];
 540                         } else {
 541                                 if ( !isset( $info['class'] ) ) {
 542                                         $class = 'ResourceLoaderFileModule';
 543                                 } else {
 544                                         $class = $info['class'];
 545                                 }
 546                                 /** @var ResourceLoaderModule $object */
 547                                 $object = new $class( $info );
 548                                 $object->setConfig( $this->getConfig() );
 549                         }
 550                         $object->setName( $name );
 551                         $this->modules[$name] = $object;
 552                 }
 553
 554                 return $this->modules[$name];
 555         }
 556
 557         /**
 558          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 559          *
 560          * @param string $name Module name
 561          * @return bool
 562          */
 563         protected function isFileModule( $name ) {
 564                 if ( !isset( $this->moduleInfos[$name] ) ) {
 565                         return false;
 566                 }
 567                 $info = $this->moduleInfos[$name];
 568                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 569                         return false;
 570                 }
 571                 return true;
 572         }
 573
 574         /**
 575          * Get the list of sources.
 576          *
 577          * @return array Like array( id => load.php url, .. )
 578          */
 579         public function getSources() {
 580                 return $this->sources;
 581         }
 582
 583         /**
 584          * Get the URL to the load.php endpoint for the given
 585          * ResourceLoader source
 586          *
 587          * @since 1.24
 588          * @param string $source
 589          * @throws MWException On an invalid $source name
 590          * @return string
 591          */
 592         public function getLoadScript( $source ) {
 593                 if ( !isset( $this->sources[$source] ) ) {
 594                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 595                 }
 596                 return $this->sources[$source];
 597         }
 598
 599         /**
 600          * @since 1.26
 601          * @param string $value
 602          * @return string Hash
 603          */
 604         public static function makeHash( $value ) {
 605                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 606                 // The first 8 chars of a base64 encoded digest represent the same binary as
 607                 // the first 12 chars of a hex encoded digest.
 608                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 609         }
 610
 611         /**
 612          * Helper method to get and combine versions of multiple modules.
 613          *
 614          * @since 1.26
 615          * @param ResourceLoaderContext $context
 616          * @param array $modules List of ResourceLoaderModule objects
 617          * @return string Hash
 618          */
 619         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 620                 if ( !$modules ) {
 621                         return '';
 622                 }
 623                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 624                 // http://php.net/functions.anonymous
 625                 $rl = $this;
 626                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 627                         return $rl->getModule( $module )->getVersionHash( $context );
 628                 }, $modules );
 629                 return self::makeHash( implode( $hashes ) );
 630         }
 631
 632         /**
 633          * Output a response to a load request, including the content-type header.
 634          *
 635          * @param ResourceLoaderContext $context Context in which a response should be formed
 636          */
 637         public function respond( ResourceLoaderContext $context ) {
 638                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 639                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 640                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 641                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 642                 // the whole thing in our own output buffer to be sure the active buffer
 643                 // doesn't use ob_gzhandler.
 644                 // See http://bugs.php.net/bug.php?id=36514
 645                 ob_start();
 646
 647                 // Find out which modules are missing and instantiate the others
 648                 $modules = array();
 649                 $missing = array();
 650                 foreach ( $context->getModules() as $name ) {
 651                         $module = $this->getModule( $name );
 652                         if ( $module ) {
 653                                 // Do not allow private modules to be loaded from the web.
 654                                 // This is a security issue, see bug 34907.
 655                                 if ( $module->getGroup() === 'private' ) {
 656                                         $this->logger->debug( "Request for private module '$name' denied" );
 657                                         $this->errors[] = "Cannot show private module \"$name\"";
 658                                         continue;
 659                                 }
 660                                 $modules[$name] = $module;
 661                         } else {
 662                                 $missing[] = $name;
 663                         }
 664                 }
 665
 666                 try {
 667                         // Preload for getCombinedVersion()
 668                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 669                 } catch ( Exception $e ) {
 670                         MWExceptionHandler::logException( $e );
 671                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 672                                 'exception' => $e
 673                         ) );
 674                         $this->errors[] = self::formatExceptionNoComment( $e );
 675                 }
 676
 677                 // Combine versions to propagate cache invalidation
 678                 $versionHash = '';
 679                 try {
 680                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 681                 } catch ( Exception $e ) {
 682                         MWExceptionHandler::logException( $e );
 683                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 684                                 'exception' => $e
 685                         ) );
 686                         $this->errors[] = self::formatExceptionNoComment( $e );
 687                 }
 688
 689                 // See RFC 2616 § 3.11 Entity Tags
 690                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 691                 $etag = 'W/"' . $versionHash . '"';
 692
 693                 // Try the client-side cache first
 694                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 695                         return; // output handled (buffers cleared)
 696                 }
 697
 698                 // Use file cache if enabled and available...
 699                 if ( $this->config->get( 'UseFileCache' ) ) {
 700                         $fileCache = ResourceFileCache::newFromContext( $context );
 701                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 702                                 return; // output handled
 703                         }
 704                 }
 705
 706                 // Generate a response
 707                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 708
 709                 // Capture any PHP warnings from the output buffer and append them to the
 710                 // error list if we're in debug mode.
 711                 if ( $context->getDebug() ) {
 712                         $warnings = ob_get_contents();
 713                         if ( strlen( $warnings ) ) {
 714                                 $this->errors[] = $warnings;
 715                         }
 716                 }
 717
 718                 // Save response to file cache unless there are errors
 719                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 720                         // Cache single modules and images...and other requests if there are enough hits
 721                         if ( ResourceFileCache::useFileCache( $context ) ) {
 722                                 if ( $fileCache->isCacheWorthy() ) {
 723                                         $fileCache->saveText( $response );
 724                                 } else {
 725                                         $fileCache->incrMissesRecent( $context->getRequest() );
 726                                 }
 727                         }
 728                 }
 729
 730                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 731
 732                 // Remove the output buffer and output the response
 733                 ob_end_clean();
 734
 735                 if ( $context->getImageObj() && $this->errors ) {
 736                         // We can't show both the error messages and the response when it's an image.
 737                         $response = implode( "\n\n", $this->errors );
 738                 } elseif ( $this->errors ) {
 739                         $errorText = implode( "\n\n", $this->errors );
 740                         $errorResponse = self::makeComment( $errorText );
 741                         if ( $context->shouldIncludeScripts() ) {
 742                                 $errorResponse .= 'if (window.console && console.error) {'
 743                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 744                                         . "}\n";
 745                         }
 746
 747                         // Prepend error info to the response
 748                         $response = $errorResponse . $response;
 749                 }
 750
 751                 $this->errors = array();
 752                 echo $response;
 753
 754         }
 755
 756         /**
 757          * Send main response headers to the client.
 758          *
 759          * Deals with Content-Type, CORS (for stylesheets), and caching.
 760          *
 761          * @param ResourceLoaderContext $context
 762          * @param string $etag ETag header value
 763          * @param bool $errors Whether there are errors in the response
 764          * @return void
 765          */
 766         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 767                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 768                 // If a version wasn't specified we need a shorter expiry time for updates
 769                 // to propagate to clients quickly
 770                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 771                 if ( is_null( $context->getVersion() ) || $errors ) {
 772                         $maxage = $rlMaxage['unversioned']['client'];
 773                         $smaxage = $rlMaxage['unversioned']['server'];
 774                 // If a version was specified we can use a longer expiry time since changing
 775                 // version numbers causes cache misses
 776                 } else {
 777                         $maxage = $rlMaxage['versioned']['client'];
 778                         $smaxage = $rlMaxage['versioned']['server'];
 779                 }
 780                 if ( $context->getImageObj() ) {
 781                         // Output different headers if we're outputting textual errors.
 782                         if ( $errors ) {
 783                                 header( 'Content-Type: text/plain; charset=utf-8' );
 784                         } else {
 785                                 $context->getImageObj()->sendResponseHeaders( $context );
 786                         }
 787                 } elseif ( $context->getOnly() === 'styles' ) {
 788                         header( 'Content-Type: text/css; charset=utf-8' );
 789                         header( 'Access-Control-Allow-Origin: *' );
 790                 } else {
 791                         header( 'Content-Type: text/javascript; charset=utf-8' );
 792                 }
 793                 // See RFC 2616 § 14.19 ETag
 794                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 795                 header( 'ETag: ' . $etag );
 796                 if ( $context->getDebug() ) {
 797                         // Do not cache debug responses
 798                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 799                         header( 'Pragma: no-cache' );
 800                 } else {
 801                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 802                         $exp = min( $maxage, $smaxage );
 803                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 804                 }
 805
 806                 // Send the current time expressed as fractional seconds since epoch,
 807                 // with microsecond precision. This helps distinguish hits from misses
 808                 // in edge caches.
 809                 header( 'MediaWiki-Timestamp: ' . microtime( true ) );
 810         }
 811
 812         /**
 813          * Respond with HTTP 304 Not Modified if appropiate.
 814          *
 815          * If there's an If-None-Match header, respond with a 304 appropriately
 816          * and clear out the output buffer. If the client cache is too old then do nothing.
 817          *
 818          * @param ResourceLoaderContext $context
 819          * @param string $etag ETag header value
 820          * @return bool True if HTTP 304 was sent and output handled
 821          */
 822         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 823                 // See RFC 2616 § 14.26 If-None-Match
 824                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 825                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 826                 // Never send 304s in debug mode
 827                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 828                         // There's another bug in ob_gzhandler (see also the comment at
 829                         // the top of this function) that causes it to gzip even empty
 830                         // responses, meaning it's impossible to produce a truly empty
 831                         // response (because the gzip header is always there). This is
 832                         // a problem because 304 responses have to be completely empty
 833                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 834                         // See also http://bugs.php.net/bug.php?id=51579
 835                         // To work around this, we tear down all output buffering before
 836                         // sending the 304.
 837                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 838
 839                         HttpStatus::header( 304 );
 840
 841                         $this->sendResponseHeaders( $context, $etag, false );
 842                         return true;
 843                 }
 844                 return false;
 845         }
 846
 847         /**
 848          * Send out code for a response from file cache if possible.
 849          *
 850          * @param ResourceFileCache $fileCache Cache object for this request URL
 851          * @param ResourceLoaderContext $context Context in which to generate a response
 852          * @param string $etag ETag header value
 853          * @return bool If this found a cache file and handled the response
 854          */
 855         protected function tryRespondFromFileCache(
 856                 ResourceFileCache $fileCache,
 857                 ResourceLoaderContext $context,
 858                 $etag
 859         ) {
 860                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 861                 // Buffer output to catch warnings.
 862                 ob_start();
 863                 // Get the maximum age the cache can be
 864                 $maxage = is_null( $context->getVersion() )
 865                         ? $rlMaxage['unversioned']['server']
 866                         : $rlMaxage['versioned']['server'];
 867                 // Minimum timestamp the cache file must have
 868                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 869                 if ( !$good ) {
 870                         try { // RL always hits the DB on file cache miss...
 871                                 wfGetDB( DB_SLAVE );
 872                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 873                                 $good = $fileCache->isCacheGood(); // cache existence check
 874                         }
 875                 }
 876                 if ( $good ) {
 877                         $ts = $fileCache->cacheTimestamp();
 878                         // Send content type and cache headers
 879                         $this->sendResponseHeaders( $context, $etag, false );
 880                         $response = $fileCache->fetchText();
 881                         // Capture any PHP warnings from the output buffer and append them to the
 882                         // response in a comment if we're in debug mode.
 883                         if ( $context->getDebug() ) {
 884                                 $warnings = ob_get_contents();
 885                                 if ( strlen( $warnings ) ) {
 886                                         $response = self::makeComment( $warnings ) . $response;
 887                                 }
 888                         }
 889                         // Remove the output buffer and output the response
 890                         ob_end_clean();
 891                         echo $response . "\n/* Cached {$ts} */";
 892                         return true; // cache hit
 893                 }
 894                 // Clear buffer
 895                 ob_end_clean();
 896
 897                 return false; // cache miss
 898         }
 899
 900         /**
 901          * Generate a CSS or JS comment block.
 902          *
 903          * Only use this for public data, not error message details.
 904          *
 905          * @param string $text
 906          * @return string
 907          */
 908         public static function makeComment( $text ) {
 909                 $encText = str_replace( '*/', '* /', $text );
 910                 return "/*\n$encText\n*/\n";
 911         }
 912
 913         /**
 914          * Handle exception display.
 915          *
 916          * @param Exception $e Exception to be shown to the user
 917          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 918          */
 919         public static function formatException( $e ) {
 920                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 921         }
 922
 923         /**
 924          * Handle exception display.
 925          *
 926          * @since 1.25
 927          * @param Exception $e Exception to be shown to the user
 928          * @return string Sanitized text that can be returned to the user
 929          */
 930         protected static function formatExceptionNoComment( $e ) {
 931                 global $wgShowExceptionDetails;
 932
 933                 if ( !$wgShowExceptionDetails ) {
 934                         return MWExceptionHandler::getPublicLogMessage( $e );
 935                 }
 936
 937                 return MWExceptionHandler::getLogMessage( $e );
 938         }
 939
 940         /**
 941          * Generate code for a response.
 942          *
 943          * @param ResourceLoaderContext $context Context in which to generate a response
 944          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 945          * @param string[] $missing List of requested module names that are unregistered (optional)
 946          * @return string Response data
 947          */
 948         public function makeModuleResponse( ResourceLoaderContext $context,
 949                 array $modules, array $missing = array()
 950         ) {
 951                 $out = '';
 952                 $states = array();
 953
 954                 if ( !count( $modules ) && !count( $missing ) ) {
 955                         return <<<MESSAGE
 956 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 957    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 958    no modules were requested. Max made me put this here. */
 959 MESSAGE;
 960                 }
 961
 962                 $image = $context->getImageObj();
 963                 if ( $image ) {
 964                         $data = $image->getImageData( $context );
 965                         if ( $data === false ) {
 966                                 $data = '';
 967                                 $this->errors[] = 'Image generation failed';
 968                         }
 969                         return $data;
 970                 }
 971
 972                 // Pre-fetch blobs
 973                 if ( $context->shouldIncludeMessages() ) {
 974                         try {
 975                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 976                         } catch ( Exception $e ) {
 977                                 MWExceptionHandler::logException( $e );
 978                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 979                                         'exception' => $e
 980                                 ) );
 981                                 $this->errors[] = self::formatExceptionNoComment( $e );
 982                         }
 983                 }
 984
 985                 foreach ( $missing as $name ) {
 986                         $states[$name] = 'missing';
 987                 }
 988
 989                 // Generate output
 990                 $isRaw = false;
 991
 992                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
 993
 994                 foreach ( $modules as $name => $module ) {
 995                         try {
 996                                 $content = $module->getModuleContent( $context );
 997                                 $strContent = '';
 998
 999                                 // Append output
1000                                 switch ( $context->getOnly() ) {
1001                                         case 'scripts':
1002                                                 $scripts = $content['scripts'];
1003                                                 if ( is_string( $scripts ) ) {
1004                                                         // Load scripts raw...
1005                                                         $strContent = $scripts;
1006                                                 } elseif ( is_array( $scripts ) ) {
1007                                                         // ...except when $scripts is an array of URLs
1008                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
1009                                                 }
1010                                                 break;
1011                                         case 'styles':
1012                                                 $styles = $content['styles'];
1013                                                 // We no longer seperate into media, they are all combined now with
1014                                                 // custom media type groups into @media .. {} sections as part of the css string.
1015                                                 // Module returns either an empty array or a numerical array with css strings.
1016                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1017                                                 break;
1018                                         default:
1019                                                 $strContent = self::makeLoaderImplementScript(
1020                                                         $name,
1021                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1022                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1023                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1024                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1025                                                 );
1026                                                 break;
1027                                 }
1028
1029                                 if ( !$context->getDebug() ) {
1030                                         $strContent = self::filter( $filter, $strContent );
1031                                 }
1032
1033                                 $out .= $strContent;
1034
1035                         } catch ( Exception $e ) {
1036                                 MWExceptionHandler::logException( $e );
1037                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1038                                         'exception' => $e
1039                                 ) );
1040                                 $this->errors[] = self::formatExceptionNoComment( $e );
1041
1042                                 // Respond to client with error-state instead of module implementation
1043                                 $states[$name] = 'error';
1044                                 unset( $modules[$name] );
1045                         }
1046                         $isRaw |= $module->isRaw();
1047                 }
1048
1049                 // Update module states
1050                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1051                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1052                                 // Set the state of modules loaded as only scripts to ready as
1053                                 // they don't have an mw.loader.implement wrapper that sets the state
1054                                 foreach ( $modules as $name => $module ) {
1055                                         $states[$name] = 'ready';
1056                                 }
1057                         }
1058
1059                         // Set the state of modules we didn't respond to with mw.loader.implement
1060                         if ( count( $states ) ) {
1061                                 $stateScript = self::makeLoaderStateScript( $states );
1062                                 if ( !$context->getDebug() ) {
1063                                         $stateScript = self::filter( 'minify-js', $stateScript );
1064                                 }
1065                                 $out .= $stateScript;
1066                         }
1067                 } else {
1068                         if ( count( $states ) ) {
1069                                 $this->errors[] = 'Problematic modules: ' .
1070                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1071                         }
1072                 }
1073
1074                 return $out;
1075         }
1076
1077         /* Static Methods */
1078
1079         /**
1080          * Return JS code that calls mw.loader.implement with given module properties.
1081          *
1082          * @param string $name Module name
1083          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1084          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1085          *   to CSS files keyed by media type
1086          * @param mixed $messages List of messages associated with this module. May either be an
1087          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1088          *   the same data, wrapped in an XmlJsCode object.
1089          * @param array $templates Keys are name of templates and values are the source of
1090          *   the template.
1091          * @throws MWException
1092          * @return string
1093          */
1094         public static function makeLoaderImplementScript(
1095                 $name, $scripts, $styles, $messages, $templates
1096         ) {
1097                 if ( is_string( $scripts ) ) {
1098                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1099                         // Transportation as string instructs mw.loader.implement to use globalEval.
1100                         if ( $name === 'site' || $name === 'user' ) {
1101                                 // Minify manually because the general makeModuleResponse() minification won't be
1102                                 // effective here due to the script being a string instead of a function. (T107377)
1103                                 if ( !ResourceLoader::inDebugMode() ) {
1104                                         $scripts = self::filter( 'minify-js', $scripts );
1105                                 }
1106                         } else {
1107                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1108                         }
1109                 } elseif ( !is_array( $scripts ) ) {
1110                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1111                 }
1112                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1113                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1114                 // of "{}". Force them to objects.
1115                 $module = array(
1116                         $name,
1117                         $scripts,
1118                         (object)$styles,
1119                         (object)$messages,
1120                         (object)$templates,
1121                 );
1122                 self::trimArray( $module );
1123
1124                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1125         }
1126
1127         /**
1128          * Returns JS code which, when called, will register a given list of messages.
1129          *
1130          * @param mixed $messages Either an associative array mapping message key to value, or a
1131          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1132          * @return string
1133          */
1134         public static function makeMessageSetScript( $messages ) {
1135                 return Xml::encodeJsCall(
1136                         'mw.messages.set',
1137                         array( (object)$messages ),
1138                         ResourceLoader::inDebugMode()
1139                 );
1140         }
1141
1142         /**
1143          * Combines an associative array mapping media type to CSS into a
1144          * single stylesheet with "@media" blocks.
1145          *
1146          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1147          * @return array
1148          */
1149         public static function makeCombinedStyles( array $stylePairs ) {
1150                 $out = array();
1151                 foreach ( $stylePairs as $media => $styles ) {
1152                         // ResourceLoaderFileModule::getStyle can return the styles
1153                         // as a string or an array of strings. This is to allow separation in
1154                         // the front-end.
1155                         $styles = (array)$styles;
1156                         foreach ( $styles as $style ) {
1157                                 $style = trim( $style );
1158                                 // Don't output an empty "@media print { }" block (bug 40498)
1159                                 if ( $style !== '' ) {
1160                                         // Transform the media type based on request params and config
1161                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1162                                         $media = OutputPage::transformCssMedia( $media );
1163
1164                                         if ( $media === '' || $media == 'all' ) {
1165                                                 $out[] = $style;
1166                                         } elseif ( is_string( $media ) ) {
1167                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1168                                         }
1169                                         // else: skip
1170                                 }
1171                         }
1172                 }
1173                 return $out;
1174         }
1175
1176         /**
1177          * Returns a JS call to mw.loader.state, which sets the state of a
1178          * module or modules to a given value. Has two calling conventions:
1179          *
1180          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1181          *         Set the state of a single module called $name to $state
1182          *
1183          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1184          *         Set the state of modules with the given names to the given states
1185          *
1186          * @param string $name
1187          * @param string $state
1188          * @return string
1189          */
1190         public static function makeLoaderStateScript( $name, $state = null ) {
1191                 if ( is_array( $name ) ) {
1192                         return Xml::encodeJsCall(
1193                                 'mw.loader.state',
1194                                 array( $name ),
1195                                 ResourceLoader::inDebugMode()
1196                         );
1197                 } else {
1198                         return Xml::encodeJsCall(
1199                                 'mw.loader.state',
1200                                 array( $name, $state ),
1201                                 ResourceLoader::inDebugMode()
1202                         );
1203                 }
1204         }
1205
1206         /**
1207          * Returns JS code which calls the script given by $script. The script will
1208          * be called with local variables name, version, dependencies and group,
1209          * which will have values corresponding to $name, $version, $dependencies
1210          * and $group as supplied.
1211          *
1212          * @param string $name Module name
1213          * @param string $version Module version hash
1214          * @param array $dependencies List of module names on which this module depends
1215          * @param string $group Group which the module is in.
1216          * @param string $source Source of the module, or 'local' if not foreign.
1217          * @param string $script JavaScript code
1218          * @return string
1219          */
1220         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1221                 $group, $source, $script
1222         ) {
1223                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1224                 return Xml::encodeJsCall(
1225                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1226                         array( $name, $version, $dependencies, $group, $source ),
1227                         ResourceLoader::inDebugMode()
1228                 );
1229         }
1230
1231         private static function isEmptyObject( stdClass $obj ) {
1232                 foreach ( $obj as $key => $value ) {
1233                         return false;
1234                 }
1235                 return true;
1236         }
1237
1238         /**
1239          * Remove empty values from the end of an array.
1240          *
1241          * Values considered empty:
1242          *
1243          * - null
1244          * - array()
1245          * - new XmlJsCode( '{}' )
1246          * - new stdClass() // (object) array()
1247          *
1248          * @param Array $array
1249          */
1250         private static function trimArray( Array &$array ) {
1251                 $i = count( $array );
1252                 while ( $i-- ) {
1253                         if ( $array[$i] === null
1254                                 || $array[$i] === array()
1255                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1256                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1257                         ) {
1258                                 unset( $array[$i] );
1259                         } else {
1260                                 break;
1261                         }
1262                 }
1263         }
1264
1265         /**
1266          * Returns JS code which calls mw.loader.register with the given
1267          * parameters. Has three calling conventions:
1268          *
1269          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1270          *        $dependencies, $group, $source, $skip
1271          *     ):
1272          *        Register a single module.
1273          *
1274          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1275          *        Register modules with the given names.
1276          *
1277          *   - ResourceLoader::makeLoaderRegisterScript( array(
1278          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1279          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1280          *        ...
1281          *     ) ):
1282          *        Registers modules with the given names and parameters.
1283          *
1284          * @param string $name Module name
1285          * @param string $version Module version hash
1286          * @param array $dependencies List of module names on which this module depends
1287          * @param string $group Group which the module is in
1288          * @param string $source Source of the module, or 'local' if not foreign
1289          * @param string $skip Script body of the skip function
1290          * @return string
1291          */
1292         public static function makeLoaderRegisterScript( $name, $version = null,
1293                 $dependencies = null, $group = null, $source = null, $skip = null
1294         ) {
1295                 if ( is_array( $name ) ) {
1296                         // Build module name index
1297                         $index = array();
1298                         foreach ( $name as $i => &$module ) {
1299                                 $index[$module[0]] = $i;
1300                         }
1301
1302                         // Transform dependency names into indexes when possible, they will be resolved by
1303                         // mw.loader.register on the other end
1304                         foreach ( $name as &$module ) {
1305                                 if ( isset( $module[2] ) ) {
1306                                         foreach ( $module[2] as &$dependency ) {
1307                                                 if ( isset( $index[$dependency] ) ) {
1308                                                         $dependency = $index[$dependency];
1309                                                 }
1310                                         }
1311                                 }
1312                         }
1313
1314                         array_walk( $name, array( 'self', 'trimArray' ) );
1315
1316                         return Xml::encodeJsCall(
1317                                 'mw.loader.register',
1318                                 array( $name ),
1319                                 ResourceLoader::inDebugMode()
1320                         );
1321                 } else {
1322                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1323                         self::trimArray( $registration );
1324                         return Xml::encodeJsCall(
1325                                 'mw.loader.register',
1326                                 $registration,
1327                                 ResourceLoader::inDebugMode()
1328                         );
1329                 }
1330         }
1331
1332         /**
1333          * Returns JS code which calls mw.loader.addSource() with the given
1334          * parameters. Has two calling conventions:
1335          *
1336          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1337          *       Register a single source
1338          *
1339          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1340          *       Register sources with the given IDs and properties.
1341          *
1342          * @param string $id Source ID
1343          * @param array $properties Source properties (see addSource())
1344          * @return string
1345          */
1346         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1347                 if ( is_array( $id ) ) {
1348                         return Xml::encodeJsCall(
1349                                 'mw.loader.addSource',
1350                                 array( $id ),
1351                                 ResourceLoader::inDebugMode()
1352                         );
1353                 } else {
1354                         return Xml::encodeJsCall(
1355                                 'mw.loader.addSource',
1356                                 array( $id, $properties ),
1357                                 ResourceLoader::inDebugMode()
1358                         );
1359                 }
1360         }
1361
1362         /**
1363          * Returns JS code which runs given JS code if the client-side framework is
1364          * present.
1365          *
1366          * @deprecated since 1.25; use makeInlineScript instead
1367          * @param string $script JavaScript code
1368          * @return string
1369          */
1370         public static function makeLoaderConditionalScript( $script ) {
1371                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1372                         trim( $script ) . "\n} );";
1373         }
1374
1375         /**
1376          * Construct an inline script tag with given JS code.
1377          *
1378          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1379          * only if the client has adequate support for MediaWiki JavaScript code.
1380          *
1381          * @param string $script JavaScript code
1382          * @return WrappedString HTML
1383          */
1384         public static function makeInlineScript( $script ) {
1385                 $js = self::makeLoaderConditionalScript( $script );
1386                 return new WrappedString(
1387                         Html::inlineScript( $js ),
1388                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1389                         "\n} );</script>"
1390                 );
1391         }
1392
1393         /**
1394          * Returns JS code which will set the MediaWiki configuration array to
1395          * the given value.
1396          *
1397          * @param array $configuration List of configuration values keyed by variable name
1398          * @return string
1399          */
1400         public static function makeConfigSetScript( array $configuration ) {
1401                 return Xml::encodeJsCall(
1402                         'mw.config.set',
1403                         array( $configuration ),
1404                         ResourceLoader::inDebugMode()
1405                 ) . ResourceLoader::FILTER_NOMIN;
1406         }
1407
1408         /**
1409          * Convert an array of module names to a packed query string.
1410          *
1411          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1412          * becomes 'foo.bar,baz|bar.baz,quux'
1413          * @param array $modules List of module names (strings)
1414          * @return string Packed query string
1415          */
1416         public static function makePackedModulesString( $modules ) {
1417                 $groups = array(); // array( prefix => array( suffixes ) )
1418                 foreach ( $modules as $module ) {
1419                         $pos = strrpos( $module, '.' );
1420                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1421                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1422                         $groups[$prefix][] = $suffix;
1423                 }
1424
1425                 $arr = array();
1426                 foreach ( $groups as $prefix => $suffixes ) {
1427                         $p = $prefix === '' ? '' : $prefix . '.';
1428                         $arr[] = $p . implode( ',', $suffixes );
1429                 }
1430                 $str = implode( '|', $arr );
1431                 return $str;
1432         }
1433
1434         /**
1435          * Determine whether debug mode was requested
1436          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1437          * @return bool
1438          */
1439         public static function inDebugMode() {
1440                 if ( self::$debugMode === null ) {
1441                         global $wgRequest, $wgResourceLoaderDebug;
1442                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1443                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1444                         );
1445                 }
1446                 return self::$debugMode;
1447         }
1448
1449         /**
1450          * Reset static members used for caching.
1451          *
1452          * Global state and $wgRequest are evil, but we're using it right
1453          * now and sometimes we need to be able to force ResourceLoader to
1454          * re-evaluate the context because it has changed (e.g. in the test suite).
1455          */
1456         public static function clearCache() {
1457                 self::$debugMode = null;
1458         }
1459
1460         /**
1461          * Build a load.php URL
1462          *
1463          * @since 1.24
1464          * @param string $source Name of the ResourceLoader source
1465          * @param ResourceLoaderContext $context
1466          * @param array $extraQuery
1467          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1468          */
1469         public function createLoaderURL( $source, ResourceLoaderContext $context,
1470                 $extraQuery = array()
1471         ) {
1472                 $query = self::createLoaderQuery( $context, $extraQuery );
1473                 $script = $this->getLoadScript( $source );
1474
1475                 return wfAppendQuery( $script, $query );
1476         }
1477
1478         /**
1479          * Build a load.php URL
1480          * @deprecated since 1.24 Use createLoaderURL() instead
1481          * @param array $modules Array of module names (strings)
1482          * @param string $lang Language code
1483          * @param string $skin Skin name
1484          * @param string|null $user User name. If null, the &user= parameter is omitted
1485          * @param string|null $version Versioning timestamp
1486          * @param bool $debug Whether the request should be in debug mode
1487          * @param string|null $only &only= parameter
1488          * @param bool $printable Printable mode
1489          * @param bool $handheld Handheld mode
1490          * @param array $extraQuery Extra query parameters to add
1491          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1492          */
1493         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1494                 $version = null, $debug = false, $only = null, $printable = false,
1495                 $handheld = false, $extraQuery = array()
1496         ) {
1497                 global $wgLoadScript;
1498
1499                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1500                         $only, $printable, $handheld, $extraQuery
1501                 );
1502
1503                 return wfAppendQuery( $wgLoadScript, $query );
1504         }
1505
1506         /**
1507          * Helper for createLoaderURL()
1508          *
1509          * @since 1.24
1510          * @see makeLoaderQuery
1511          * @param ResourceLoaderContext $context
1512          * @param array $extraQuery
1513          * @return array
1514          */
1515         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1516                 return self::makeLoaderQuery(
1517                         $context->getModules(),
1518                         $context->getLanguage(),
1519                         $context->getSkin(),
1520                         $context->getUser(),
1521                         $context->getVersion(),
1522                         $context->getDebug(),
1523                         $context->getOnly(),
1524                         $context->getRequest()->getBool( 'printable' ),
1525                         $context->getRequest()->getBool( 'handheld' ),
1526                         $extraQuery
1527                 );
1528         }
1529
1530         /**
1531          * Build a query array (array representation of query string) for load.php. Helper
1532          * function for makeLoaderURL().
1533          *
1534          * @param array $modules
1535          * @param string $lang
1536          * @param string $skin
1537          * @param string $user
1538          * @param string $version
1539          * @param bool $debug
1540          * @param string $only
1541          * @param bool $printable
1542          * @param bool $handheld
1543          * @param array $extraQuery
1544          *
1545          * @return array
1546          */
1547         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1548                 $version = null, $debug = false, $only = null, $printable = false,
1549                 $handheld = false, $extraQuery = array()
1550         ) {
1551                 $query = array(
1552                         'modules' => self::makePackedModulesString( $modules ),
1553                         'lang' => $lang,
1554                         'skin' => $skin,
1555                         'debug' => $debug ? 'true' : 'false',
1556                 );
1557                 if ( $user !== null ) {
1558                         $query['user'] = $user;
1559                 }
1560                 if ( $version !== null ) {
1561                         $query['version'] = $version;
1562                 }
1563                 if ( $only !== null ) {
1564                         $query['only'] = $only;
1565                 }
1566                 if ( $printable ) {
1567                         $query['printable'] = 1;
1568                 }
1569                 if ( $handheld ) {
1570                         $query['handheld'] = 1;
1571                 }
1572                 $query += $extraQuery;
1573
1574                 // Make queries uniform in order
1575                 ksort( $query );
1576                 return $query;
1577         }
1578
1579         /**
1580          * Check a module name for validity.
1581          *
1582          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1583          * at most 255 bytes.
1584          *
1585          * @param string $moduleName Module name to check
1586          * @return bool Whether $moduleName is a valid module name
1587          */
1588         public static function isValidModuleName( $moduleName ) {
1589                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1590         }
1591
1592         /**
1593          * Returns LESS compiler set up for use with MediaWiki
1594          *
1595          * @since 1.22
1596          * @since 1.27 added $extraVars parameter
1597          * @param Config $config
1598          * @param array $extraVars Associative array of extra (i.e., other than the
1599          *   globally-configured ones) that should be used for compilation.
1600          * @throws MWException
1601          * @return Less_Parser
1602          */
1603         public static function getLessCompiler( Config $config, $extraVars = array() ) {
1604                 // When called from the installer, it is possible that a required PHP extension
1605                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1606                 // exception (caught by the installer) to prevent a fatal error later on.
1607                 if ( !class_exists( 'Less_Parser' ) ) {
1608                         throw new MWException( 'MediaWiki requires the less.php parser' );
1609                 }
1610
1611                 $parser = new Less_Parser;
1612                 $parser->ModifyVars( array_merge( self::getLessVars( $config ), $extraVars ) );
1613                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1614                 $parser->SetOption( 'relativeUrls', false );
1615                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1616
1617                 return $parser;
1618         }
1619
1620         /**
1621          * Get global LESS variables.
1622          *
1623          * @param Config $config
1624          * @since 1.22
1625          * @return array Map of variable names to string CSS values.
1626          */
1627         public static function getLessVars( Config $config ) {
1628                 if ( !self::$lessVars ) {
1629                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1630                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1631                         self::$lessVars = $lessVars;
1632                 }
1633                 return self::$lessVars;
1634         }
1635 }