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 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /** @var array */
  39         private static $lessVars = null;
  40
  41         /**
  42          * Module name/ResourceLoaderModule object pairs
  43          * @var array
  44          */
  45         protected $modules = array();
  46
  47         /**
  48          * Associative array mapping module name to info associative array
  49          * @var array
  50          */
  51         protected $moduleInfos = array();
  52
  53         /** @var Config $config */
  54         private $config;
  55
  56         /**
  57          * Associative array mapping framework ids to a list of names of test suite modules
  58          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  59          * @var array
  60          */
  61         protected $testModuleNames = array();
  62
  63         /**
  64          * E.g. array( 'source-id' => 'http://.../load.php' )
  65          * @var array
  66          */
  67         protected $sources = array();
  68
  69         /**
  70          * Errors accumulated during current respond() call.
  71          * @var array
  72          */
  73         protected $errors = array();
  74
  75         /**
  76          * @var MessageBlobStore
  77          */
  78         protected $blobStore;
  79
  80         /**
  81          * Load information stored in the database about modules.
  82          *
  83          * This method grabs modules dependencies from the database and updates modules
  84          * objects.
  85          *
  86          * This is not inside the module code because it is much faster to
  87          * request all of the information at once than it is to have each module
  88          * requests its own information. This sacrifice of modularity yields a substantial
  89          * performance improvement.
  90          *
  91          * @param array $modules List of module names to preload information for
  92          * @param ResourceLoaderContext $context Context to load the information within
  93          */
  94         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  95                 if ( !count( $modules ) ) {
  96                         // Or else Database*::select() will explode, plus it's cheaper!
  97                         return;
  98                 }
  99                 $dbr = wfGetDB( DB_SLAVE );
 100                 $skin = $context->getSkin();
 101                 $lang = $context->getLanguage();
 102
 103                 // Get file dependency information
 104                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 105                                 'md_module' => $modules,
 106                                 'md_skin' => $skin
 107                         ), __METHOD__
 108                 );
 109
 110                 // Set modules' dependencies
 111                 $modulesWithDeps = array();
 112                 foreach ( $res as $row ) {
 113                         $module = $this->getModule( $row->md_module );
 114                         if ( $module ) {
 115                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 116                                 $modulesWithDeps[] = $row->md_module;
 117                         }
 118                 }
 119
 120                 // Register the absence of a dependency row too
 121                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 122                         $module = $this->getModule( $name );
 123                         if ( $module ) {
 124                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 125                         }
 126                 }
 127
 128                 // Get message blob mtimes. Only do this for modules with messages
 129                 $modulesWithMessages = array();
 130                 foreach ( $modules as $name ) {
 131                         $module = $this->getModule( $name );
 132                         if ( $module && count( $module->getMessages() ) ) {
 133                                 $modulesWithMessages[] = $name;
 134                         }
 135                 }
 136                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 137                 if ( count( $modulesWithMessages ) ) {
 138                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 139                                         'mr_resource' => $modulesWithMessages,
 140                                         'mr_lang' => $lang
 141                                 ), __METHOD__
 142                         );
 143                         foreach ( $res as $row ) {
 144                                 $module = $this->getModule( $row->mr_resource );
 145                                 if ( $module ) {
 146                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 147                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 148                                 }
 149                         }
 150                 }
 151                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 152                         $module = $this->getModule( $name );
 153                         if ( $module ) {
 154                                 $module->setMsgBlobMtime( $lang, 1 );
 155                         }
 156                 }
 157         }
 158
 159         /**
 160          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 161          *
 162          * Available filters are:
 163          *
 164          *    - minify-js \see JavaScriptMinifier::minify
 165          *    - minify-css \see CSSMin::minify
 166          *
 167          * If $data is empty, only contains whitespace or the filter was unknown,
 168          * $data is returned unmodified.
 169          *
 170          * @param string $filter Name of filter to run
 171          * @param string $data Text to filter, such as JavaScript or CSS text
 172          * @param array $options For back-compat, can also be the boolean value for "cacheReport". Keys:
 173          *  - (bool) cache: Whether to allow caching this data. Default: true.
 174          *  - (bool) cacheReport: Whether to include the "cache key" report comment. Default: true.
 175          * @return string Filtered data, or a comment containing an error message
 176          */
 177         public function filter( $filter, $data, $options = array() ) {
 178                 // Back-compat
 179                 if ( is_bool( $options ) ) {
 180                         $options = array( 'cacheReport' => $options );
 181                 }
 182                 // Defaults
 183                 $options += array( 'cache' => true, 'cacheReport' => true );
 184
 185                 // Don't filter empty content
 186                 if ( trim( $data ) === '' ) {
 187                         return $data;
 188                 }
 189
 190                 if ( !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 191                         wfDebugLog( 'resourceloader', __METHOD__ . ": Invalid filter: $filter" );
 192                         return $data;
 193                 }
 194
 195                 if ( !$options['cache'] ) {
 196                         $result = $this->applyFilter( $filter, $data );
 197                 } else {
 198                         // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 199                         $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 200                         $cache = wfGetCache( CACHE_ANYTHING );
 201                         $cacheEntry = $cache->get( $key );
 202                         if ( is_string( $cacheEntry ) ) {
 203                                 wfIncrStats( "rl-$filter-cache-hits" );
 204                                 return $cacheEntry;
 205                         }
 206                         $result = '';
 207                         try {
 208                                 wfIncrStats( "rl-$filter-cache-misses" );
 209                                 $result = $this->applyFilter( $filter, $data );
 210                                 if ( $options['cacheReport'] ) {
 211                                         $result .= "\n/* cache key: $key */";
 212                                 }
 213                                 $cache->set( $key, $result );
 214                         } catch ( Exception $e ) {
 215                                 MWExceptionHandler::logException( $e );
 216                                 wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 217                                 $this->errors[] = self::formatExceptionNoComment( $e );
 218                         }
 219                 }
 220
 221                 return $result;
 222         }
 223
 224         private function applyFilter( $filter, $data ) {
 225                         switch ( $filter ) {
 226                                 case 'minify-js':
 227                                         return JavaScriptMinifier::minify( $data,
 228                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 229                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 230                                         );
 231                                 case 'minify-css':
 232                                         return CSSMin::minify( $data );
 233                         }
 234                         return $data;
 235         }
 236
 237         /* Methods */
 238
 239         /**
 240          * Register core modules and runs registration hooks.
 241          * @param Config|null $config
 242          */
 243         public function __construct( Config $config = null ) {
 244                 global $IP;
 245
 246                 if ( $config === null ) {
 247                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 248                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 249                 }
 250
 251                 $this->config = $config;
 252
 253                 // Add 'local' source first
 254                 $this->addSource( 'local', wfScript( 'load' ) );
 255
 256                 // Add other sources
 257                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 258
 259                 // Register core modules
 260                 $this->register( include "$IP/resources/Resources.php" );
 261                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 262                 // Register extension modules
 263                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 264                 $this->register( $config->get( 'ResourceModules' ) );
 265
 266                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 267                         $this->registerTestModules();
 268                 }
 269
 270                 $this->setMessageBlobStore( new MessageBlobStore() );
 271         }
 272
 273         /**
 274          * @return Config
 275          */
 276         public function getConfig() {
 277                 return $this->config;
 278         }
 279
 280         /**
 281          * @param MessageBlobStore $blobStore
 282          * @since 1.25
 283          */
 284         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 285                 $this->blobStore = $blobStore;
 286         }
 287
 288         /**
 289          * Register a module with the ResourceLoader system.
 290          *
 291          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 292          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 293          *   this may also be a ResourceLoaderModule object. Optional when using
 294          *   multiple-registration calling style.
 295          * @throws MWException If a duplicate module registration is attempted
 296          * @throws MWException If a module name contains illegal characters (pipes or commas)
 297          * @throws MWException If something other than a ResourceLoaderModule is being registered
 298          * @return bool False if there were any errors, in which case one or more modules were
 299          *   not registered
 300          */
 301         public function register( $name, $info = null ) {
 302
 303                 // Allow multiple modules to be registered in one call
 304                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 305                 foreach ( $registrations as $name => $info ) {
 306                         // Disallow duplicate registrations
 307                         if ( isset( $this->moduleInfos[$name] ) ) {
 308                                 // A module has already been registered by this name
 309                                 throw new MWException(
 310                                         'ResourceLoader duplicate registration error. ' .
 311                                         'Another module has already been registered as ' . $name
 312                                 );
 313                         }
 314
 315                         // Check $name for validity
 316                         if ( !self::isValidModuleName( $name ) ) {
 317                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 318                                         . "see ResourceLoader::isValidModuleName()" );
 319                         }
 320
 321                         // Attach module
 322                         if ( $info instanceof ResourceLoaderModule ) {
 323                                 $this->moduleInfos[$name] = array( 'object' => $info );
 324                                 $info->setName( $name );
 325                                 $this->modules[$name] = $info;
 326                         } elseif ( is_array( $info ) ) {
 327                                 // New calling convention
 328                                 $this->moduleInfos[$name] = $info;
 329                         } else {
 330                                 throw new MWException(
 331                                         'ResourceLoader module info type error for module \'' . $name .
 332                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 333                                 );
 334                         }
 335
 336                         // Last-minute changes
 337
 338                         // Apply custom skin-defined styles to existing modules.
 339                         if ( $this->isFileModule( $name ) ) {
 340                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 341                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 342                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 343                                                 continue;
 344                                         }
 345
 346                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 347                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 348                                         if ( isset( $skinStyles[$name] ) ) {
 349                                                 $paths = (array)$skinStyles[$name];
 350                                                 $styleFiles = array();
 351                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 352                                                 $paths = (array)$skinStyles['+' . $name];
 353                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 354                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 355                                                         array();
 356                                         } else {
 357                                                 continue;
 358                                         }
 359
 360                                         // Add new file paths, remapping them to refer to our directories and not use settings
 361                                         // from the module we're modifying, which come from the base definition.
 362                                         list( $localBasePath, $remoteBasePath ) =
 363                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 364
 365                                         foreach ( $paths as $path ) {
 366                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 367                                         }
 368
 369                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 370                                 }
 371                         }
 372                 }
 373
 374         }
 375
 376         /**
 377          */
 378         public function registerTestModules() {
 379                 global $IP;
 380
 381                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 382                         throw new MWException( 'Attempt to register JavaScript test modules '
 383                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 384                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 385                 }
 386
 387                 // Get core test suites
 388                 $testModules = array();
 389                 $testModules['qunit'] = array();
 390                 // Get other test suites (e.g. from extensions)
 391                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 392
 393                 // Add the testrunner (which configures QUnit) to the dependencies.
 394                 // Since it must be ready before any of the test suites are executed.
 395                 foreach ( $testModules['qunit'] as &$module ) {
 396                         // Make sure all test modules are top-loading so that when QUnit starts
 397                         // on document-ready, it will run once and finish. If some tests arrive
 398                         // later (possibly after QUnit has already finished) they will be ignored.
 399                         $module['position'] = 'top';
 400                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 401                 }
 402
 403                 $testModules['qunit'] =
 404                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 405
 406                 foreach ( $testModules as $id => $names ) {
 407                         // Register test modules
 408                         $this->register( $testModules[$id] );
 409
 410                         // Keep track of their names so that they can be loaded together
 411                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 412                 }
 413
 414         }
 415
 416         /**
 417          * Add a foreign source of modules.
 418          *
 419          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 420          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 421          *  backwards-compatibility.
 422          * @throws MWException
 423          */
 424         public function addSource( $id, $loadUrl = null ) {
 425                 // Allow multiple sources to be registered in one call
 426                 if ( is_array( $id ) ) {
 427                         foreach ( $id as $key => $value ) {
 428                                 $this->addSource( $key, $value );
 429                         }
 430                         return;
 431                 }
 432
 433                 // Disallow duplicates
 434                 if ( isset( $this->sources[$id] ) ) {
 435                         throw new MWException(
 436                                 'ResourceLoader duplicate source addition error. ' .
 437                                 'Another source has already been registered as ' . $id
 438                         );
 439                 }
 440
 441                 // Pre 1.24 backwards-compatibility
 442                 if ( is_array( $loadUrl ) ) {
 443                         if ( !isset( $loadUrl['loadScript'] ) ) {
 444                                 throw new MWException(
 445                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 446                                 );
 447                         }
 448
 449                         $loadUrl = $loadUrl['loadScript'];
 450                 }
 451
 452                 $this->sources[$id] = $loadUrl;
 453         }
 454
 455         /**
 456          * Get a list of module names.
 457          *
 458          * @return array List of module names
 459          */
 460         public function getModuleNames() {
 461                 return array_keys( $this->moduleInfos );
 462         }
 463
 464         /**
 465          * Get a list of test module names for one (or all) frameworks.
 466          *
 467          * If the given framework id is unknkown, or if the in-object variable is not an array,
 468          * then it will return an empty array.
 469          *
 470          * @param string $framework Get only the test module names for one
 471          *   particular framework (optional)
 472          * @return array
 473          */
 474         public function getTestModuleNames( $framework = 'all' ) {
 475                 /** @todo api siteinfo prop testmodulenames modulenames */
 476                 if ( $framework == 'all' ) {
 477                         return $this->testModuleNames;
 478                 } elseif ( isset( $this->testModuleNames[$framework] )
 479                         && is_array( $this->testModuleNames[$framework] )
 480                 ) {
 481                         return $this->testModuleNames[$framework];
 482                 } else {
 483                         return array();
 484                 }
 485         }
 486
 487         /**
 488          * Check whether a ResourceLoader module is registered
 489          *
 490          * @since 1.25
 491          * @param string $name
 492          * @return bool
 493          */
 494         public function isModuleRegistered( $name ) {
 495                 return isset( $this->moduleInfos[$name] );
 496         }
 497
 498         /**
 499          * Get the ResourceLoaderModule object for a given module name.
 500          *
 501          * If an array of module parameters exists but a ResourceLoaderModule object has not
 502          * yet been instantiated, this method will instantiate and cache that object such that
 503          * subsequent calls simply return the same object.
 504          *
 505          * @param string $name Module name
 506          * @return ResourceLoaderModule|null If module has been registered, return a
 507          *  ResourceLoaderModule instance. Otherwise, return null.
 508          */
 509         public function getModule( $name ) {
 510                 if ( !isset( $this->modules[$name] ) ) {
 511                         if ( !isset( $this->moduleInfos[$name] ) ) {
 512                                 // No such module
 513                                 return null;
 514                         }
 515                         // Construct the requested object
 516                         $info = $this->moduleInfos[$name];
 517                         /** @var ResourceLoaderModule $object */
 518                         if ( isset( $info['object'] ) ) {
 519                                 // Object given in info array
 520                                 $object = $info['object'];
 521                         } else {
 522                                 if ( !isset( $info['class'] ) ) {
 523                                         $class = 'ResourceLoaderFileModule';
 524                                 } else {
 525                                         $class = $info['class'];
 526                                 }
 527                                 /** @var ResourceLoaderModule $object */
 528                                 $object = new $class( $info );
 529                                 $object->setConfig( $this->getConfig() );
 530                         }
 531                         $object->setName( $name );
 532                         $this->modules[$name] = $object;
 533                 }
 534
 535                 return $this->modules[$name];
 536         }
 537
 538         /**
 539          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 540          *
 541          * @param string $name Module name
 542          * @return bool
 543          */
 544         protected function isFileModule( $name ) {
 545                 if ( !isset( $this->moduleInfos[$name] ) ) {
 546                         return false;
 547                 }
 548                 $info = $this->moduleInfos[$name];
 549                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 550                         return false;
 551                 }
 552                 return true;
 553         }
 554
 555         /**
 556          * Get the list of sources.
 557          *
 558          * @return array Like array( id => load.php url, .. )
 559          */
 560         public function getSources() {
 561                 return $this->sources;
 562         }
 563
 564         /**
 565          * Get the URL to the load.php endpoint for the given
 566          * ResourceLoader source
 567          *
 568          * @since 1.24
 569          * @param string $source
 570          * @throws MWException On an invalid $source name
 571          * @return string
 572          */
 573         public function getLoadScript( $source ) {
 574                 if ( !isset( $this->sources[$source] ) ) {
 575                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 576                 }
 577                 return $this->sources[$source];
 578         }
 579
 580         /**
 581          * @since 1.26
 582          * @param string $value
 583          * @return string Hash
 584          */
 585         public static function makeHash( $value ) {
 586                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 587                 // The first 8 chars of a base64 encoded digest represent the same binary as
 588                 // the first 12 chars of a hex encoded digest.
 589                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 590         }
 591
 592         /**
 593          * Helper method to get and combine versions of multiple modules.
 594          *
 595          * @since 1.26
 596          * @param ResourceLoaderContext $context
 597          * @param array $modules List of ResourceLoaderModule objects
 598          * @return string Hash
 599          */
 600         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 601                 if ( !$modules ) {
 602                         return '';
 603                 }
 604                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 605                 // http://php.net/functions.anonymous
 606                 $rl = $this;
 607                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 608                         return $rl->getModule( $module )->getVersionHash( $context );
 609                 }, $modules );
 610                 return self::makeHash( implode( $hashes ) );
 611         }
 612
 613         /**
 614          * Output a response to a load request, including the content-type header.
 615          *
 616          * @param ResourceLoaderContext $context Context in which a response should be formed
 617          */
 618         public function respond( ResourceLoaderContext $context ) {
 619                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 620                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 621                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 622                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 623                 // the whole thing in our own output buffer to be sure the active buffer
 624                 // doesn't use ob_gzhandler.
 625                 // See http://bugs.php.net/bug.php?id=36514
 626                 ob_start();
 627
 628                 // Find out which modules are missing and instantiate the others
 629                 $modules = array();
 630                 $missing = array();
 631                 foreach ( $context->getModules() as $name ) {
 632                         $module = $this->getModule( $name );
 633                         if ( $module ) {
 634                                 // Do not allow private modules to be loaded from the web.
 635                                 // This is a security issue, see bug 34907.
 636                                 if ( $module->getGroup() === 'private' ) {
 637                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 638                                         $this->errors[] = "Cannot show private module \"$name\"";
 639                                         continue;
 640                                 }
 641                                 $modules[$name] = $module;
 642                         } else {
 643                                 $missing[] = $name;
 644                         }
 645                 }
 646
 647                 try {
 648                         // Preload for getCombinedVersion()
 649                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 650                 } catch ( Exception $e ) {
 651                         MWExceptionHandler::logException( $e );
 652                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 653                         $this->errors[] = self::formatExceptionNoComment( $e );
 654                 }
 655
 656                 // Combine versions to propagate cache invalidation
 657                 $versionHash = '';
 658                 try {
 659                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 660                 } catch ( Exception $e ) {
 661                         MWExceptionHandler::logException( $e );
 662                         wfDebugLog( 'resourceloader', __METHOD__ . ": calculating version hash failed: $e" );
 663                         $this->errors[] = self::formatExceptionNoComment( $e );
 664                 }
 665
 666                 // See RFC 2616 § 3.11 Entity Tags
 667                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 668                 $etag = 'W/"' . $versionHash . '"';
 669
 670                 // Try the client-side cache first
 671                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 672                         return; // output handled (buffers cleared)
 673                 }
 674
 675                 // Use file cache if enabled and available...
 676                 if ( $this->config->get( 'UseFileCache' ) ) {
 677                         $fileCache = ResourceFileCache::newFromContext( $context );
 678                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 679                                 return; // output handled
 680                         }
 681                 }
 682
 683                 // Generate a response
 684                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 685
 686                 // Capture any PHP warnings from the output buffer and append them to the
 687                 // error list if we're in debug mode.
 688                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 689                         $this->errors[] = $warnings;
 690                 }
 691
 692                 // Save response to file cache unless there are errors
 693                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 694                         // Cache single modules and images...and other requests if there are enough hits
 695                         if ( ResourceFileCache::useFileCache( $context ) ) {
 696                                 if ( $fileCache->isCacheWorthy() ) {
 697                                         $fileCache->saveText( $response );
 698                                 } else {
 699                                         $fileCache->incrMissesRecent( $context->getRequest() );
 700                                 }
 701                         }
 702                 }
 703
 704                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 705
 706                 // Remove the output buffer and output the response
 707                 ob_end_clean();
 708
 709                 if ( $context->getImageObj() && $this->errors ) {
 710                         // We can't show both the error messages and the response when it's an image.
 711                         $errorText = '';
 712                         foreach ( $this->errors as $error ) {
 713                                 $errorText .= $error . "\n";
 714                         }
 715                         $response = $errorText;
 716                 } elseif ( $this->errors ) {
 717                         // Prepend comments indicating errors
 718                         $errorText = '';
 719                         foreach ( $this->errors as $error ) {
 720                                 $errorText .= self::makeComment( $error );
 721                         }
 722                         $response = $errorText . $response;
 723                 }
 724
 725                 $this->errors = array();
 726                 echo $response;
 727
 728         }
 729
 730         /**
 731          * Send main response headers to the client.
 732          *
 733          * Deals with Content-Type, CORS (for stylesheets), and caching.
 734          *
 735          * @param ResourceLoaderContext $context
 736          * @param string $etag ETag header value
 737          * @param bool $errors Whether there are errors in the response
 738          * @return void
 739          */
 740         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 741                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 742                 // If a version wasn't specified we need a shorter expiry time for updates
 743                 // to propagate to clients quickly
 744                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 745                 if ( is_null( $context->getVersion() ) || $errors ) {
 746                         $maxage = $rlMaxage['unversioned']['client'];
 747                         $smaxage = $rlMaxage['unversioned']['server'];
 748                 // If a version was specified we can use a longer expiry time since changing
 749                 // version numbers causes cache misses
 750                 } else {
 751                         $maxage = $rlMaxage['versioned']['client'];
 752                         $smaxage = $rlMaxage['versioned']['server'];
 753                 }
 754                 if ( $context->getImageObj() ) {
 755                         // Output different headers if we're outputting textual errors.
 756                         if ( $errors ) {
 757                                 header( 'Content-Type: text/plain; charset=utf-8' );
 758                         } else {
 759                                 $context->getImageObj()->sendResponseHeaders( $context );
 760                         }
 761                 } elseif ( $context->getOnly() === 'styles' ) {
 762                         header( 'Content-Type: text/css; charset=utf-8' );
 763                         header( 'Access-Control-Allow-Origin: *' );
 764                 } else {
 765                         header( 'Content-Type: text/javascript; charset=utf-8' );
 766                 }
 767                 // See RFC 2616 § 14.19 ETag
 768                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 769                 header( 'ETag: ' . $etag );
 770                 if ( $context->getDebug() ) {
 771                         // Do not cache debug responses
 772                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 773                         header( 'Pragma: no-cache' );
 774                 } else {
 775                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 776                         $exp = min( $maxage, $smaxage );
 777                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 778                 }
 779         }
 780
 781         /**
 782          * Respond with HTTP 304 Not Modified if appropiate.
 783          *
 784          * If there's an If-None-Match header, respond with a 304 appropriately
 785          * and clear out the output buffer. If the client cache is too old then do nothing.
 786          *
 787          * @param ResourceLoaderContext $context
 788          * @param string $etag ETag header value
 789          * @return bool True if HTTP 304 was sent and output handled
 790          */
 791         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 792                 // See RFC 2616 § 14.26 If-None-Match
 793                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 794                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 795                 // Never send 304s in debug mode
 796                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 797                         // There's another bug in ob_gzhandler (see also the comment at
 798                         // the top of this function) that causes it to gzip even empty
 799                         // responses, meaning it's impossible to produce a truly empty
 800                         // response (because the gzip header is always there). This is
 801                         // a problem because 304 responses have to be completely empty
 802                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 803                         // See also http://bugs.php.net/bug.php?id=51579
 804                         // To work around this, we tear down all output buffering before
 805                         // sending the 304.
 806                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 807
 808                         header( 'HTTP/1.0 304 Not Modified' );
 809                         header( 'Status: 304 Not Modified' );
 810
 811                         $this->sendResponseHeaders( $context, $etag, false );
 812                         return true;
 813                 }
 814                 return false;
 815         }
 816
 817         /**
 818          * Send out code for a response from file cache if possible.
 819          *
 820          * @param ResourceFileCache $fileCache Cache object for this request URL
 821          * @param ResourceLoaderContext $context Context in which to generate a response
 822          * @param string $etag ETag header value
 823          * @return bool If this found a cache file and handled the response
 824          */
 825         protected function tryRespondFromFileCache(
 826                 ResourceFileCache $fileCache,
 827                 ResourceLoaderContext $context,
 828                 $etag
 829         ) {
 830                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 831                 // Buffer output to catch warnings.
 832                 ob_start();
 833                 // Get the maximum age the cache can be
 834                 $maxage = is_null( $context->getVersion() )
 835                         ? $rlMaxage['unversioned']['server']
 836                         : $rlMaxage['versioned']['server'];
 837                 // Minimum timestamp the cache file must have
 838                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 839                 if ( !$good ) {
 840                         try { // RL always hits the DB on file cache miss...
 841                                 wfGetDB( DB_SLAVE );
 842                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 843                                 $good = $fileCache->isCacheGood(); // cache existence check
 844                         }
 845                 }
 846                 if ( $good ) {
 847                         $ts = $fileCache->cacheTimestamp();
 848                         // Send content type and cache headers
 849                         $this->sendResponseHeaders( $context, $etag, false );
 850                         $response = $fileCache->fetchText();
 851                         // Capture any PHP warnings from the output buffer and append them to the
 852                         // response in a comment if we're in debug mode.
 853                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 854                                 $response = self::makeComment( $warnings ) . $response;
 855                         }
 856                         // Remove the output buffer and output the response
 857                         ob_end_clean();
 858                         echo $response . "\n/* Cached {$ts} */";
 859                         return true; // cache hit
 860                 }
 861                 // Clear buffer
 862                 ob_end_clean();
 863
 864                 return false; // cache miss
 865         }
 866
 867         /**
 868          * Generate a CSS or JS comment block.
 869          *
 870          * Only use this for public data, not error message details.
 871          *
 872          * @param string $text
 873          * @return string
 874          */
 875         public static function makeComment( $text ) {
 876                 $encText = str_replace( '*/', '* /', $text );
 877                 return "/*\n$encText\n*/\n";
 878         }
 879
 880         /**
 881          * Handle exception display.
 882          *
 883          * @param Exception $e Exception to be shown to the user
 884          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 885          */
 886         public static function formatException( $e ) {
 887                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 888         }
 889
 890         /**
 891          * Handle exception display.
 892          *
 893          * @since 1.25
 894          * @param Exception $e Exception to be shown to the user
 895          * @return string Sanitized text that can be returned to the user
 896          */
 897         protected static function formatExceptionNoComment( $e ) {
 898                 global $wgShowExceptionDetails;
 899
 900                 if ( $wgShowExceptionDetails ) {
 901                         return $e->__toString();
 902                 } else {
 903                         return wfMessage( 'internalerror' )->text();
 904                 }
 905         }
 906
 907         /**
 908          * Generate code for a response.
 909          *
 910          * @param ResourceLoaderContext $context Context in which to generate a response
 911          * @param array $modules List of module objects keyed by module name
 912          * @param array $missing List of requested module names that are unregistered (optional)
 913          * @return string Response data
 914          */
 915         public function makeModuleResponse( ResourceLoaderContext $context,
 916                 array $modules, array $missing = array()
 917         ) {
 918                 $out = '';
 919                 $states = array();
 920
 921                 if ( !count( $modules ) && !count( $missing ) ) {
 922                         return <<<MESSAGE
 923 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 924    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 925    no modules were requested. Max made me put this here. */
 926 MESSAGE;
 927                 }
 928
 929                 $image = $context->getImageObj();
 930                 if ( $image ) {
 931                         $data = $image->getImageData( $context );
 932                         if ( $data === false ) {
 933                                 $data = '';
 934                                 $this->errors[] = 'Image generation failed';
 935                         }
 936                         return $data;
 937                 }
 938
 939                 // Pre-fetch blobs
 940                 if ( $context->shouldIncludeMessages() ) {
 941                         try {
 942                                 $blobs = $this->blobStore->get( $this, $modules, $context->getLanguage() );
 943                         } catch ( Exception $e ) {
 944                                 MWExceptionHandler::logException( $e );
 945                                 wfDebugLog(
 946                                         'resourceloader',
 947                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 948                                 );
 949                                 $this->errors[] = self::formatExceptionNoComment( $e );
 950                         }
 951                 } else {
 952                         $blobs = array();
 953                 }
 954
 955                 foreach ( $missing as $name ) {
 956                         $states[$name] = 'missing';
 957                 }
 958
 959                 // Generate output
 960                 $isRaw = false;
 961                 foreach ( $modules as $name => $module ) {
 962                         /**
 963                          * @var $module ResourceLoaderModule
 964                          */
 965
 966                         try {
 967                                 $scripts = '';
 968                                 if ( $context->shouldIncludeScripts() ) {
 969                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 970                                         // However, we can't do this if the module doesn't support it
 971                                         // We also can't do this if there is an only= parameter, because we have to give
 972                                         // the module a way to return a load.php URL without causing an infinite loop
 973                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 974                                                 $scripts = $module->getScriptURLsForDebug( $context );
 975                                         } else {
 976                                                 $scripts = $module->getScript( $context );
 977                                                 // rtrim() because there are usually a few line breaks
 978                                                 // after the last ';'. A new line at EOF, a new line
 979                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 980                                                 if ( is_string( $scripts )
 981                                                         && strlen( $scripts )
 982                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 983                                                 ) {
 984                                                         // Append semicolon to prevent weird bugs caused by files not
 985                                                         // terminating their statements right (bug 27054)
 986                                                         $scripts .= ";\n";
 987                                                 }
 988                                         }
 989                                 }
 990                                 // Styles
 991                                 $styles = array();
 992                                 if ( $context->shouldIncludeStyles() ) {
 993                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 994                                         // that don't *have* any stylesheets (bug 38024).
 995                                         $stylePairs = $module->getStyles( $context );
 996                                         if ( count( $stylePairs ) ) {
 997                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 998                                                 // See comment near shouldIncludeScripts() for more details
 999                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
1000                                                         $styles = array(
1001                                                                 'url' => $module->getStyleURLsForDebug( $context )
1002                                                         );
1003                                                 } else {
1004                                                         // Minify CSS before embedding in mw.loader.implement call
1005                                                         // (unless in debug mode)
1006                                                         if ( !$context->getDebug() ) {
1007                                                                 foreach ( $stylePairs as $media => $style ) {
1008                                                                         // Can be either a string or an array of strings.
1009                                                                         if ( is_array( $style ) ) {
1010                                                                                 $stylePairs[$media] = array();
1011                                                                                 foreach ( $style as $cssText ) {
1012                                                                                         if ( is_string( $cssText ) ) {
1013                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
1014                                                                                         }
1015                                                                                 }
1016                                                                         } elseif ( is_string( $style ) ) {
1017                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
1018                                                                         }
1019                                                                 }
1020                                                         }
1021                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
1022                                                         $styles = array(
1023                                                                 'css' => self::makeCombinedStyles( $stylePairs )
1024                                                         );
1025                                                 }
1026                                         }
1027                                 }
1028
1029                                 // Messages
1030                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
1031
1032                                 // Append output
1033                                 switch ( $context->getOnly() ) {
1034                                         case 'scripts':
1035                                                 if ( is_string( $scripts ) ) {
1036                                                         // Load scripts raw...
1037                                                         $out .= $scripts;
1038                                                 } elseif ( is_array( $scripts ) ) {
1039                                                         // ...except when $scripts is an array of URLs
1040                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
1041                                                 }
1042                                                 break;
1043                                         case 'styles':
1044                                                 // We no longer seperate into media, they are all combined now with
1045                                                 // custom media type groups into @media .. {} sections as part of the css string.
1046                                                 // Module returns either an empty array or a numerical array with css strings.
1047                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1048                                                 break;
1049                                         default:
1050                                                 $out .= self::makeLoaderImplementScript(
1051                                                         $name,
1052                                                         $scripts,
1053                                                         $styles,
1054                                                         new XmlJsCode( $messagesBlob ),
1055                                                         $module->getTemplates()
1056                                                 );
1057                                                 break;
1058                                 }
1059                         } catch ( Exception $e ) {
1060                                 MWExceptionHandler::logException( $e );
1061                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1062                                 $this->errors[] = self::formatExceptionNoComment( $e );
1063
1064                                 // Respond to client with error-state instead of module implementation
1065                                 $states[$name] = 'error';
1066                                 unset( $modules[$name] );
1067                         }
1068                         $isRaw |= $module->isRaw();
1069                 }
1070
1071                 // Update module states
1072                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1073                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1074                                 // Set the state of modules loaded as only scripts to ready as
1075                                 // they don't have an mw.loader.implement wrapper that sets the state
1076                                 foreach ( $modules as $name => $module ) {
1077                                         $states[$name] = 'ready';
1078                                 }
1079                         }
1080
1081                         // Set the state of modules we didn't respond to with mw.loader.implement
1082                         if ( count( $states ) ) {
1083                                 $out .= self::makeLoaderStateScript( $states );
1084                         }
1085                 } else {
1086                         if ( count( $states ) ) {
1087                                 $this->errors[] = 'Problematic modules: ' .
1088                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1089                         }
1090                 }
1091
1092                 $enableFilterCache = true;
1093                 if ( count( $modules ) === 1 && reset( $modules ) instanceof ResourceLoaderUserTokensModule ) {
1094                         // If we're building the embedded user.tokens, don't cache (T84960)
1095                         $enableFilterCache = false;
1096                 }
1097
1098                 if ( !$context->getDebug() ) {
1099                         if ( $context->getOnly() === 'styles' ) {
1100                                 $out = $this->filter( 'minify-css', $out );
1101                         } else {
1102                                 $out = $this->filter( 'minify-js', $out, array(
1103                                         'cache' => $enableFilterCache
1104                                 ) );
1105                         }
1106                 }
1107
1108                 return $out;
1109         }
1110
1111         /* Static Methods */
1112
1113         /**
1114          * Return JS code that calls mw.loader.implement with given module properties.
1115          *
1116          * @param string $name Module name
1117          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1118          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1119          *   to CSS files keyed by media type
1120          * @param mixed $messages List of messages associated with this module. May either be an
1121          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1122          *   the same data, wrapped in an XmlJsCode object.
1123          * @param array $templates Keys are name of templates and values are the source of
1124          *   the template.
1125          * @throws MWException
1126          * @return string
1127          */
1128         public static function makeLoaderImplementScript(
1129                 $name, $scripts, $styles, $messages, $templates
1130         ) {
1131                 if ( is_string( $scripts ) ) {
1132                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1133                 } elseif ( !is_array( $scripts ) ) {
1134                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1135                 }
1136                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1137                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1138                 // of "{}". Force them to objects.
1139                 $module = array(
1140                         $name,
1141                         $scripts,
1142                         (object) $styles,
1143                         (object) $messages,
1144                         (object) $templates,
1145                 );
1146                 self::trimArray( $module );
1147
1148                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1149         }
1150
1151         /**
1152          * Returns JS code which, when called, will register a given list of messages.
1153          *
1154          * @param mixed $messages Either an associative array mapping message key to value, or a
1155          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1156          * @return string
1157          */
1158         public static function makeMessageSetScript( $messages ) {
1159                 return Xml::encodeJsCall(
1160                         'mw.messages.set',
1161                         array( (object)$messages ),
1162                         ResourceLoader::inDebugMode()
1163                 );
1164         }
1165
1166         /**
1167          * Combines an associative array mapping media type to CSS into a
1168          * single stylesheet with "@media" blocks.
1169          *
1170          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1171          * @return array
1172          */
1173         public static function makeCombinedStyles( array $stylePairs ) {
1174                 $out = array();
1175                 foreach ( $stylePairs as $media => $styles ) {
1176                         // ResourceLoaderFileModule::getStyle can return the styles
1177                         // as a string or an array of strings. This is to allow separation in
1178                         // the front-end.
1179                         $styles = (array)$styles;
1180                         foreach ( $styles as $style ) {
1181                                 $style = trim( $style );
1182                                 // Don't output an empty "@media print { }" block (bug 40498)
1183                                 if ( $style !== '' ) {
1184                                         // Transform the media type based on request params and config
1185                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1186                                         $media = OutputPage::transformCssMedia( $media );
1187
1188                                         if ( $media === '' || $media == 'all' ) {
1189                                                 $out[] = $style;
1190                                         } elseif ( is_string( $media ) ) {
1191                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1192                                         }
1193                                         // else: skip
1194                                 }
1195                         }
1196                 }
1197                 return $out;
1198         }
1199
1200         /**
1201          * Returns a JS call to mw.loader.state, which sets the state of a
1202          * module or modules to a given value. Has two calling conventions:
1203          *
1204          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1205          *         Set the state of a single module called $name to $state
1206          *
1207          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1208          *         Set the state of modules with the given names to the given states
1209          *
1210          * @param string $name
1211          * @param string $state
1212          * @return string
1213          */
1214         public static function makeLoaderStateScript( $name, $state = null ) {
1215                 if ( is_array( $name ) ) {
1216                         return Xml::encodeJsCall(
1217                                 'mw.loader.state',
1218                                 array( $name ),
1219                                 ResourceLoader::inDebugMode()
1220                         );
1221                 } else {
1222                         return Xml::encodeJsCall(
1223                                 'mw.loader.state',
1224                                 array( $name, $state ),
1225                                 ResourceLoader::inDebugMode()
1226                         );
1227                 }
1228         }
1229
1230         /**
1231          * Returns JS code which calls the script given by $script. The script will
1232          * be called with local variables name, version, dependencies and group,
1233          * which will have values corresponding to $name, $version, $dependencies
1234          * and $group as supplied.
1235          *
1236          * @param string $name Module name
1237          * @param string $version Module version hash
1238          * @param array $dependencies List of module names on which this module depends
1239          * @param string $group Group which the module is in.
1240          * @param string $source Source of the module, or 'local' if not foreign.
1241          * @param string $script JavaScript code
1242          * @return string
1243          */
1244         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1245                 $group, $source, $script
1246         ) {
1247                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1248                 return Xml::encodeJsCall(
1249                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1250                         array( $name, $version, $dependencies, $group, $source ),
1251                         ResourceLoader::inDebugMode()
1252                 );
1253         }
1254
1255         private static function isEmptyObject( stdClass $obj ) {
1256                 foreach ( $obj as $key => &$value ) {
1257                         return false;
1258                 }
1259                 return true;
1260         }
1261
1262         /**
1263          * Remove empty values from the end of an array.
1264          *
1265          * Values considered empty:
1266          *
1267          * - null
1268          * - array()
1269          * - new XmlJsCode( '{}' )
1270          * - new stdClass() // (object) array()
1271          *
1272          * @param Array $array
1273          */
1274         private static function trimArray( Array &$array ) {
1275                 $i = count( $array );
1276                 while ( $i-- ) {
1277                         if ( $array[$i] === null
1278                                 || $array[$i] === array()
1279                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1280                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1281                         ) {
1282                                 unset( $array[$i] );
1283                         } else {
1284                                 break;
1285                         }
1286                 }
1287         }
1288
1289         /**
1290          * Returns JS code which calls mw.loader.register with the given
1291          * parameters. Has three calling conventions:
1292          *
1293          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1294          *        $dependencies, $group, $source, $skip
1295          *     ):
1296          *        Register a single module.
1297          *
1298          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1299          *        Register modules with the given names.
1300          *
1301          *   - ResourceLoader::makeLoaderRegisterScript( array(
1302          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1303          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1304          *        ...
1305          *     ) ):
1306          *        Registers modules with the given names and parameters.
1307          *
1308          * @param string $name Module name
1309          * @param string $version Module version hash
1310          * @param array $dependencies List of module names on which this module depends
1311          * @param string $group Group which the module is in
1312          * @param string $source Source of the module, or 'local' if not foreign
1313          * @param string $skip Script body of the skip function
1314          * @return string
1315          */
1316         public static function makeLoaderRegisterScript( $name, $version = null,
1317                 $dependencies = null, $group = null, $source = null, $skip = null
1318         ) {
1319                 if ( is_array( $name ) ) {
1320                         // Build module name index
1321                         $index = array();
1322                         foreach ( $name as $i => &$module ) {
1323                                 $index[$module[0]] = $i;
1324                         }
1325
1326                         // Transform dependency names into indexes when possible, they will be resolved by
1327                         // mw.loader.register on the other end
1328                         foreach ( $name as &$module ) {
1329                                 if ( isset( $module[2] ) ) {
1330                                         foreach ( $module[2] as &$dependency ) {
1331                                                 if ( isset( $index[$dependency] ) ) {
1332                                                         $dependency = $index[$dependency];
1333                                                 }
1334                                         }
1335                                 }
1336                         }
1337
1338                         array_walk( $name, array( 'self', 'trimArray' ) );
1339
1340                         return Xml::encodeJsCall(
1341                                 'mw.loader.register',
1342                                 array( $name ),
1343                                 ResourceLoader::inDebugMode()
1344                         );
1345                 } else {
1346                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1347                         self::trimArray( $registration );
1348                         return Xml::encodeJsCall(
1349                                 'mw.loader.register',
1350                                 $registration,
1351                                 ResourceLoader::inDebugMode()
1352                         );
1353                 }
1354         }
1355
1356         /**
1357          * Returns JS code which calls mw.loader.addSource() with the given
1358          * parameters. Has two calling conventions:
1359          *
1360          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1361          *       Register a single source
1362          *
1363          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1364          *       Register sources with the given IDs and properties.
1365          *
1366          * @param string $id Source ID
1367          * @param array $properties Source properties (see addSource())
1368          * @return string
1369          */
1370         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1371                 if ( is_array( $id ) ) {
1372                         return Xml::encodeJsCall(
1373                                 'mw.loader.addSource',
1374                                 array( $id ),
1375                                 ResourceLoader::inDebugMode()
1376                         );
1377                 } else {
1378                         return Xml::encodeJsCall(
1379                                 'mw.loader.addSource',
1380                                 array( $id, $properties ),
1381                                 ResourceLoader::inDebugMode()
1382                         );
1383                 }
1384         }
1385
1386         /**
1387          * Returns JS code which runs given JS code if the client-side framework is
1388          * present.
1389          *
1390          * @deprecated since 1.25; use makeInlineScript instead
1391          * @param string $script JavaScript code
1392          * @return string
1393          */
1394         public static function makeLoaderConditionalScript( $script ) {
1395                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1396         }
1397
1398         /**
1399          * Construct an inline script tag with given JS code.
1400          *
1401          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1402          * only if the client has adequate support for MediaWiki JavaScript code.
1403          *
1404          * @param string $script JavaScript code
1405          * @return string HTML
1406          */
1407         public static function makeInlineScript( $script ) {
1408                 $js = self::makeLoaderConditionalScript( $script );
1409                 return Html::inlineScript( $js );
1410         }
1411
1412         /**
1413          * Returns JS code which will set the MediaWiki configuration array to
1414          * the given value.
1415          *
1416          * @param array $configuration List of configuration values keyed by variable name
1417          * @return string
1418          */
1419         public static function makeConfigSetScript( array $configuration ) {
1420                 return Xml::encodeJsCall(
1421                         'mw.config.set',
1422                         array( $configuration ),
1423                         ResourceLoader::inDebugMode()
1424                 );
1425         }
1426
1427         /**
1428          * Convert an array of module names to a packed query string.
1429          *
1430          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1431          * becomes 'foo.bar,baz|bar.baz,quux'
1432          * @param array $modules List of module names (strings)
1433          * @return string Packed query string
1434          */
1435         public static function makePackedModulesString( $modules ) {
1436                 $groups = array(); // array( prefix => array( suffixes ) )
1437                 foreach ( $modules as $module ) {
1438                         $pos = strrpos( $module, '.' );
1439                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1440                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1441                         $groups[$prefix][] = $suffix;
1442                 }
1443
1444                 $arr = array();
1445                 foreach ( $groups as $prefix => $suffixes ) {
1446                         $p = $prefix === '' ? '' : $prefix . '.';
1447                         $arr[] = $p . implode( ',', $suffixes );
1448                 }
1449                 $str = implode( '|', $arr );
1450                 return $str;
1451         }
1452
1453         /**
1454          * Determine whether debug mode was requested
1455          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1456          * @return bool
1457          */
1458         public static function inDebugMode() {
1459                 if ( self::$debugMode === null ) {
1460                         global $wgRequest, $wgResourceLoaderDebug;
1461                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1462                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1463                         );
1464                 }
1465                 return self::$debugMode;
1466         }
1467
1468         /**
1469          * Reset static members used for caching.
1470          *
1471          * Global state and $wgRequest are evil, but we're using it right
1472          * now and sometimes we need to be able to force ResourceLoader to
1473          * re-evaluate the context because it has changed (e.g. in the test suite).
1474          */
1475         public static function clearCache() {
1476                 self::$debugMode = null;
1477         }
1478
1479         /**
1480          * Build a load.php URL
1481          *
1482          * @since 1.24
1483          * @param string $source Name of the ResourceLoader source
1484          * @param ResourceLoaderContext $context
1485          * @param array $extraQuery
1486          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1487          */
1488         public function createLoaderURL( $source, ResourceLoaderContext $context,
1489                 $extraQuery = array()
1490         ) {
1491                 $query = self::createLoaderQuery( $context, $extraQuery );
1492                 $script = $this->getLoadScript( $source );
1493
1494                 // Prevent the IE6 extension check from being triggered (bug 28840)
1495                 // by appending a character that's invalid in Windows extensions ('*')
1496                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1497         }
1498
1499         /**
1500          * Build a load.php URL
1501          * @deprecated since 1.24 Use createLoaderURL() instead
1502          * @param array $modules Array of module names (strings)
1503          * @param string $lang Language code
1504          * @param string $skin Skin name
1505          * @param string|null $user User name. If null, the &user= parameter is omitted
1506          * @param string|null $version Versioning timestamp
1507          * @param bool $debug Whether the request should be in debug mode
1508          * @param string|null $only &only= parameter
1509          * @param bool $printable Printable mode
1510          * @param bool $handheld Handheld mode
1511          * @param array $extraQuery Extra query parameters to add
1512          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1513          */
1514         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1515                 $version = null, $debug = false, $only = null, $printable = false,
1516                 $handheld = false, $extraQuery = array()
1517         ) {
1518                 global $wgLoadScript;
1519
1520                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1521                         $only, $printable, $handheld, $extraQuery
1522                 );
1523
1524                 // Prevent the IE6 extension check from being triggered (bug 28840)
1525                 // by appending a character that's invalid in Windows extensions ('*')
1526                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1527         }
1528
1529         /**
1530          * Helper for createLoaderURL()
1531          *
1532          * @since 1.24
1533          * @see makeLoaderQuery
1534          * @param ResourceLoaderContext $context
1535          * @param array $extraQuery
1536          * @return array
1537          */
1538         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1539                 return self::makeLoaderQuery(
1540                         $context->getModules(),
1541                         $context->getLanguage(),
1542                         $context->getSkin(),
1543                         $context->getUser(),
1544                         $context->getVersion(),
1545                         $context->getDebug(),
1546                         $context->getOnly(),
1547                         $context->getRequest()->getBool( 'printable' ),
1548                         $context->getRequest()->getBool( 'handheld' ),
1549                         $extraQuery
1550                 );
1551         }
1552
1553         /**
1554          * Build a query array (array representation of query string) for load.php. Helper
1555          * function for makeLoaderURL().
1556          *
1557          * @param array $modules
1558          * @param string $lang
1559          * @param string $skin
1560          * @param string $user
1561          * @param string $version
1562          * @param bool $debug
1563          * @param string $only
1564          * @param bool $printable
1565          * @param bool $handheld
1566          * @param array $extraQuery
1567          *
1568          * @return array
1569          */
1570         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1571                 $version = null, $debug = false, $only = null, $printable = false,
1572                 $handheld = false, $extraQuery = array()
1573         ) {
1574                 $query = array(
1575                         'modules' => self::makePackedModulesString( $modules ),
1576                         'lang' => $lang,
1577                         'skin' => $skin,
1578                         'debug' => $debug ? 'true' : 'false',
1579                 );
1580                 if ( $user !== null ) {
1581                         $query['user'] = $user;
1582                 }
1583                 if ( $version !== null ) {
1584                         $query['version'] = $version;
1585                 }
1586                 if ( $only !== null ) {
1587                         $query['only'] = $only;
1588                 }
1589                 if ( $printable ) {
1590                         $query['printable'] = 1;
1591                 }
1592                 if ( $handheld ) {
1593                         $query['handheld'] = 1;
1594                 }
1595                 $query += $extraQuery;
1596
1597                 // Make queries uniform in order
1598                 ksort( $query );
1599                 return $query;
1600         }
1601
1602         /**
1603          * Check a module name for validity.
1604          *
1605          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1606          * at most 255 bytes.
1607          *
1608          * @param string $moduleName Module name to check
1609          * @return bool Whether $moduleName is a valid module name
1610          */
1611         public static function isValidModuleName( $moduleName ) {
1612                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1613         }
1614
1615         /**
1616          * Returns LESS compiler set up for use with MediaWiki
1617          *
1618          * @param Config $config
1619          * @throws MWException
1620          * @since 1.22
1621          * @return lessc
1622          */
1623         public static function getLessCompiler( Config $config ) {
1624                 // When called from the installer, it is possible that a required PHP extension
1625                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1626                 // exception (caught by the installer) to prevent a fatal error later on.
1627                 if ( !class_exists( 'lessc' ) ) {
1628                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1629                 }
1630                 if ( !function_exists( 'ctype_digit' ) ) {
1631                         throw new MWException( 'lessc requires the Ctype extension' );
1632                 }
1633
1634                 $less = new lessc();
1635                 $less->setPreserveComments( true );
1636                 $less->setVariables( self::getLessVars( $config ) );
1637                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1638                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1639                         $less->registerFunction( $name, $func );
1640                 }
1641                 return $less;
1642         }
1643
1644         /**
1645          * Get global LESS variables.
1646          *
1647          * @param Config $config
1648          * @since 1.22
1649          * @return array Map of variable names to string CSS values.
1650          */
1651         public static function getLessVars( Config $config ) {
1652                 if ( !self::$lessVars ) {
1653                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1654                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1655                         // Sort by key to ensure consistent hashing for cache lookups.
1656                         ksort( $lessVars );
1657                         self::$lessVars = $lessVars;
1658                 }
1659                 return self::$lessVars;
1660         }
1661 }