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         /**
  91          * Load information stored in the database about modules.
  92          *
  93          * This method grabs modules dependencies from the database and updates modules
  94          * objects.
  95          *
  96          * This is not inside the module code because it is much faster to
  97          * request all of the information at once than it is to have each module
  98          * requests its own information. This sacrifice of modularity yields a substantial
  99          * performance improvement.
 100          *
 101          * @param array $modules List of module names to preload information for
 102          * @param ResourceLoaderContext $context Context to load the information within
 103          */
 104         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
 105                 if ( !count( $modules ) ) {
 106                         // Or else Database*::select() will explode, plus it's cheaper!
 107                         return;
 108                 }
 109                 $dbr = wfGetDB( DB_SLAVE );
 110                 $skin = $context->getSkin();
 111                 $lang = $context->getLanguage();
 112
 113                 // Get file dependency information
 114                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 115                                 'md_module' => $modules,
 116                                 'md_skin' => $skin
 117                         ), __METHOD__
 118                 );
 119
 120                 // Set modules' dependencies
 121                 $modulesWithDeps = array();
 122                 foreach ( $res as $row ) {
 123                         $module = $this->getModule( $row->md_module );
 124                         if ( $module ) {
 125                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 126                                 $modulesWithDeps[] = $row->md_module;
 127                         }
 128                 }
 129
 130                 // Register the absence of a dependency row too
 131                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 132                         $module = $this->getModule( $name );
 133                         if ( $module ) {
 134                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 135                         }
 136                 }
 137
 138                 // Get message blob mtimes. Only do this for modules with messages
 139                 $modulesWithMessages = array();
 140                 foreach ( $modules as $name ) {
 141                         $module = $this->getModule( $name );
 142                         if ( $module && count( $module->getMessages() ) ) {
 143                                 $modulesWithMessages[] = $name;
 144                         }
 145                 }
 146                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 147                 if ( count( $modulesWithMessages ) ) {
 148                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 149                                         'mr_resource' => $modulesWithMessages,
 150                                         'mr_lang' => $lang
 151                                 ), __METHOD__
 152                         );
 153                         foreach ( $res as $row ) {
 154                                 $module = $this->getModule( $row->mr_resource );
 155                                 if ( $module ) {
 156                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 157                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 158                                 }
 159                         }
 160                 }
 161                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 162                         $module = $this->getModule( $name );
 163                         if ( $module ) {
 164                                 $module->setMsgBlobMtime( $lang, 1 );
 165                         }
 166                 }
 167         }
 168
 169         /**
 170          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 171          *
 172          * Available filters are:
 173          *
 174          *    - minify-js \see JavaScriptMinifier::minify
 175          *    - minify-css \see CSSMin::minify
 176          *
 177          * If $data is empty, only contains whitespace or the filter was unknown,
 178          * $data is returned unmodified.
 179          *
 180          * @param string $filter Name of filter to run
 181          * @param string $data Text to filter, such as JavaScript or CSS text
 182          * @param array $options For back-compat, can also be the boolean value for "cacheReport". Keys:
 183          *  - (bool) cache: Whether to allow caching this data. Default: true.
 184          *  - (bool) cacheReport: Whether to include the "cache key" report comment. Default: false.
 185          * @return string Filtered data, or a comment containing an error message
 186          */
 187         public function filter( $filter, $data, $options = array() ) {
 188                 // Back-compat
 189                 if ( is_bool( $options ) ) {
 190                         $options = array( 'cacheReport' => $options );
 191                 }
 192                 // Defaults
 193                 $options += array( 'cache' => true, 'cacheReport' => false );
 194                 $stats = RequestContext::getMain()->getStats();
 195
 196                 // Don't filter empty content
 197                 if ( trim( $data ) === '' ) {
 198                         return $data;
 199                 }
 200
 201                 if ( !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 202                         $this->logger->warning( 'Invalid filter {filter}', array(
 203                                 'filter' => $filter
 204                         ) );
 205                         return $data;
 206                 }
 207
 208                 if ( !$options['cache'] ) {
 209                         $result = self::applyFilter( $filter, $data, $this->config );
 210                 } else {
 211                         $key = wfGlobalCacheKey(
 212                                 'resourceloader',
 213                                 'filter',
 214                                 $filter,
 215                                 self::$filterCacheVersion, md5( $data )
 216                         );
 217                         $cache = wfGetCache( wfIsHHVM() ? CACHE_ACCEL : CACHE_ANYTHING );
 218                         $cacheEntry = $cache->get( $key );
 219                         if ( is_string( $cacheEntry ) ) {
 220                                 $stats->increment( "resourceloader_cache.$filter.hit" );
 221                                 return $cacheEntry;
 222                         }
 223                         $result = '';
 224                         try {
 225                                 $statStart = microtime( true );
 226                                 $result = self::applyFilter( $filter, $data, $this->config );
 227                                 $statTiming = microtime( true ) - $statStart;
 228                                 $stats->increment( "resourceloader_cache.$filter.miss" );
 229                                 $stats->timing( "resourceloader_cache.$filter.timing", 1000 * $statTiming );
 230                                 if ( $options['cacheReport'] ) {
 231                                         $result .= "\n/* cache key: $key */";
 232                                 }
 233                                 // Set a TTL since HHVM's APC doesn't have any limitation or eviction logic.
 234                                 $cache->set( $key, $result, 24 * 3600 );
 235                         } catch ( Exception $e ) {
 236                                 MWExceptionHandler::logException( $e );
 237                                 $this->logger->warning( 'Minification failed: {exception}', array(
 238                                         'exception' => $e
 239                                 ) );
 240                                 $this->errors[] = self::formatExceptionNoComment( $e );
 241                         }
 242                 }
 243
 244                 return $result;
 245         }
 246
 247         private static function applyFilter( $filter, $data, Config $config ) {
 248                 switch ( $filter ) {
 249                         case 'minify-js':
 250                                 return JavaScriptMinifier::minify( $data,
 251                                         $config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 252                                         $config->get( 'ResourceLoaderMinifierMaxLineLength' )
 253                                 );
 254                         case 'minify-css':
 255                                 return CSSMin::minify( $data );
 256                 }
 257
 258                 return $data;
 259         }
 260
 261         /* Methods */
 262
 263         /**
 264          * Register core modules and runs registration hooks.
 265          * @param Config|null $config
 266          */
 267         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 268                 global $IP;
 269
 270                 if ( !$logger ) {
 271                         $logger = new NullLogger();
 272                 }
 273                 $this->setLogger( $logger );
 274
 275                 if ( !$config ) {
 276                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 277                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 278                 }
 279                 $this->config = $config;
 280
 281                 // Add 'local' source first
 282                 $this->addSource( 'local', wfScript( 'load' ) );
 283
 284                 // Add other sources
 285                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 286
 287                 // Register core modules
 288                 $this->register( include "$IP/resources/Resources.php" );
 289                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 290                 // Register extension modules
 291                 $this->register( $config->get( 'ResourceModules' ) );
 292                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 293
 294                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 295                         $this->registerTestModules();
 296                 }
 297
 298                 $this->setMessageBlobStore( new MessageBlobStore() );
 299         }
 300
 301         /**
 302          * @return Config
 303          */
 304         public function getConfig() {
 305                 return $this->config;
 306         }
 307
 308         public function setLogger( LoggerInterface $logger ) {
 309                 $this->logger = $logger;
 310         }
 311
 312         /**
 313          * @since 1.26
 314          * @return MessageBlobStore
 315          */
 316         public function getMessageBlobStore() {
 317                 return $this->blobStore;
 318         }
 319
 320         /**
 321          * @since 1.25
 322          * @param MessageBlobStore $blobStore
 323          */
 324         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 325                 $this->blobStore = $blobStore;
 326         }
 327
 328         /**
 329          * Register a module with the ResourceLoader system.
 330          *
 331          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 332          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 333          *   this may also be a ResourceLoaderModule object. Optional when using
 334          *   multiple-registration calling style.
 335          * @throws MWException If a duplicate module registration is attempted
 336          * @throws MWException If a module name contains illegal characters (pipes or commas)
 337          * @throws MWException If something other than a ResourceLoaderModule is being registered
 338          * @return bool False if there were any errors, in which case one or more modules were
 339          *   not registered
 340          */
 341         public function register( $name, $info = null ) {
 342
 343                 // Allow multiple modules to be registered in one call
 344                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 345                 foreach ( $registrations as $name => $info ) {
 346                         // Disallow duplicate registrations
 347                         if ( isset( $this->moduleInfos[$name] ) ) {
 348                                 // A module has already been registered by this name
 349                                 throw new MWException(
 350                                         'ResourceLoader duplicate registration error. ' .
 351                                         'Another module has already been registered as ' . $name
 352                                 );
 353                         }
 354
 355                         // Check $name for validity
 356                         if ( !self::isValidModuleName( $name ) ) {
 357                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 358                                         . "see ResourceLoader::isValidModuleName()" );
 359                         }
 360
 361                         // Attach module
 362                         if ( $info instanceof ResourceLoaderModule ) {
 363                                 $this->moduleInfos[$name] = array( 'object' => $info );
 364                                 $info->setName( $name );
 365                                 $this->modules[$name] = $info;
 366                         } elseif ( is_array( $info ) ) {
 367                                 // New calling convention
 368                                 $this->moduleInfos[$name] = $info;
 369                         } else {
 370                                 throw new MWException(
 371                                         'ResourceLoader module info type error for module \'' . $name .
 372                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 373                                 );
 374                         }
 375
 376                         // Last-minute changes
 377
 378                         // Apply custom skin-defined styles to existing modules.
 379                         if ( $this->isFileModule( $name ) ) {
 380                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 381                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 382                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 383                                                 continue;
 384                                         }
 385
 386                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 387                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 388                                         if ( isset( $skinStyles[$name] ) ) {
 389                                                 $paths = (array)$skinStyles[$name];
 390                                                 $styleFiles = array();
 391                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 392                                                 $paths = (array)$skinStyles['+' . $name];
 393                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 394                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 395                                                         array();
 396                                         } else {
 397                                                 continue;
 398                                         }
 399
 400                                         // Add new file paths, remapping them to refer to our directories and not use settings
 401                                         // from the module we're modifying, which come from the base definition.
 402                                         list( $localBasePath, $remoteBasePath ) =
 403                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 404
 405                                         foreach ( $paths as $path ) {
 406                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 407                                         }
 408
 409                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 410                                 }
 411                         }
 412                 }
 413
 414         }
 415
 416         /**
 417          */
 418         public function registerTestModules() {
 419                 global $IP;
 420
 421                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 422                         throw new MWException( 'Attempt to register JavaScript test modules '
 423                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 424                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 425                 }
 426
 427                 // Get core test suites
 428                 $testModules = array();
 429                 $testModules['qunit'] = array();
 430                 // Get other test suites (e.g. from extensions)
 431                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 432
 433                 // Add the testrunner (which configures QUnit) to the dependencies.
 434                 // Since it must be ready before any of the test suites are executed.
 435                 foreach ( $testModules['qunit'] as &$module ) {
 436                         // Make sure all test modules are top-loading so that when QUnit starts
 437                         // on document-ready, it will run once and finish. If some tests arrive
 438                         // later (possibly after QUnit has already finished) they will be ignored.
 439                         $module['position'] = 'top';
 440                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 441                 }
 442
 443                 $testModules['qunit'] =
 444                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 445
 446                 foreach ( $testModules as $id => $names ) {
 447                         // Register test modules
 448                         $this->register( $testModules[$id] );
 449
 450                         // Keep track of their names so that they can be loaded together
 451                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 452                 }
 453
 454         }
 455
 456         /**
 457          * Add a foreign source of modules.
 458          *
 459          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 460          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 461          *  backwards-compatibility.
 462          * @throws MWException
 463          */
 464         public function addSource( $id, $loadUrl = null ) {
 465                 // Allow multiple sources to be registered in one call
 466                 if ( is_array( $id ) ) {
 467                         foreach ( $id as $key => $value ) {
 468                                 $this->addSource( $key, $value );
 469                         }
 470                         return;
 471                 }
 472
 473                 // Disallow duplicates
 474                 if ( isset( $this->sources[$id] ) ) {
 475                         throw new MWException(
 476                                 'ResourceLoader duplicate source addition error. ' .
 477                                 'Another source has already been registered as ' . $id
 478                         );
 479                 }
 480
 481                 // Pre 1.24 backwards-compatibility
 482                 if ( is_array( $loadUrl ) ) {
 483                         if ( !isset( $loadUrl['loadScript'] ) ) {
 484                                 throw new MWException(
 485                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 486                                 );
 487                         }
 488
 489                         $loadUrl = $loadUrl['loadScript'];
 490                 }
 491
 492                 $this->sources[$id] = $loadUrl;
 493         }
 494
 495         /**
 496          * Get a list of module names.
 497          *
 498          * @return array List of module names
 499          */
 500         public function getModuleNames() {
 501                 return array_keys( $this->moduleInfos );
 502         }
 503
 504         /**
 505          * Get a list of test module names for one (or all) frameworks.
 506          *
 507          * If the given framework id is unknkown, or if the in-object variable is not an array,
 508          * then it will return an empty array.
 509          *
 510          * @param string $framework Get only the test module names for one
 511          *   particular framework (optional)
 512          * @return array
 513          */
 514         public function getTestModuleNames( $framework = 'all' ) {
 515                 /** @todo api siteinfo prop testmodulenames modulenames */
 516                 if ( $framework == 'all' ) {
 517                         return $this->testModuleNames;
 518                 } elseif ( isset( $this->testModuleNames[$framework] )
 519                         && is_array( $this->testModuleNames[$framework] )
 520                 ) {
 521                         return $this->testModuleNames[$framework];
 522                 } else {
 523                         return array();
 524                 }
 525         }
 526
 527         /**
 528          * Check whether a ResourceLoader module is registered
 529          *
 530          * @since 1.25
 531          * @param string $name
 532          * @return bool
 533          */
 534         public function isModuleRegistered( $name ) {
 535                 return isset( $this->moduleInfos[$name] );
 536         }
 537
 538         /**
 539          * Get the ResourceLoaderModule object for a given module name.
 540          *
 541          * If an array of module parameters exists but a ResourceLoaderModule object has not
 542          * yet been instantiated, this method will instantiate and cache that object such that
 543          * subsequent calls simply return the same object.
 544          *
 545          * @param string $name Module name
 546          * @return ResourceLoaderModule|null If module has been registered, return a
 547          *  ResourceLoaderModule instance. Otherwise, return null.
 548          */
 549         public function getModule( $name ) {
 550                 if ( !isset( $this->modules[$name] ) ) {
 551                         if ( !isset( $this->moduleInfos[$name] ) ) {
 552                                 // No such module
 553                                 return null;
 554                         }
 555                         // Construct the requested object
 556                         $info = $this->moduleInfos[$name];
 557                         /** @var ResourceLoaderModule $object */
 558                         if ( isset( $info['object'] ) ) {
 559                                 // Object given in info array
 560                                 $object = $info['object'];
 561                         } else {
 562                                 if ( !isset( $info['class'] ) ) {
 563                                         $class = 'ResourceLoaderFileModule';
 564                                 } else {
 565                                         $class = $info['class'];
 566                                 }
 567                                 /** @var ResourceLoaderModule $object */
 568                                 $object = new $class( $info );
 569                                 $object->setConfig( $this->getConfig() );
 570                         }
 571                         $object->setName( $name );
 572                         $this->modules[$name] = $object;
 573                 }
 574
 575                 return $this->modules[$name];
 576         }
 577
 578         /**
 579          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 580          *
 581          * @param string $name Module name
 582          * @return bool
 583          */
 584         protected function isFileModule( $name ) {
 585                 if ( !isset( $this->moduleInfos[$name] ) ) {
 586                         return false;
 587                 }
 588                 $info = $this->moduleInfos[$name];
 589                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 590                         return false;
 591                 }
 592                 return true;
 593         }
 594
 595         /**
 596          * Get the list of sources.
 597          *
 598          * @return array Like array( id => load.php url, .. )
 599          */
 600         public function getSources() {
 601                 return $this->sources;
 602         }
 603
 604         /**
 605          * Get the URL to the load.php endpoint for the given
 606          * ResourceLoader source
 607          *
 608          * @since 1.24
 609          * @param string $source
 610          * @throws MWException On an invalid $source name
 611          * @return string
 612          */
 613         public function getLoadScript( $source ) {
 614                 if ( !isset( $this->sources[$source] ) ) {
 615                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 616                 }
 617                 return $this->sources[$source];
 618         }
 619
 620         /**
 621          * @since 1.26
 622          * @param string $value
 623          * @return string Hash
 624          */
 625         public static function makeHash( $value ) {
 626                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 627                 // The first 8 chars of a base64 encoded digest represent the same binary as
 628                 // the first 12 chars of a hex encoded digest.
 629                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 630         }
 631
 632         /**
 633          * Helper method to get and combine versions of multiple modules.
 634          *
 635          * @since 1.26
 636          * @param ResourceLoaderContext $context
 637          * @param array $modules List of ResourceLoaderModule objects
 638          * @return string Hash
 639          */
 640         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 641                 if ( !$modules ) {
 642                         return '';
 643                 }
 644                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 645                 // http://php.net/functions.anonymous
 646                 $rl = $this;
 647                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 648                         return $rl->getModule( $module )->getVersionHash( $context );
 649                 }, $modules );
 650                 return self::makeHash( implode( $hashes ) );
 651         }
 652
 653         /**
 654          * Output a response to a load request, including the content-type header.
 655          *
 656          * @param ResourceLoaderContext $context Context in which a response should be formed
 657          */
 658         public function respond( ResourceLoaderContext $context ) {
 659                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 660                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 661                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 662                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 663                 // the whole thing in our own output buffer to be sure the active buffer
 664                 // doesn't use ob_gzhandler.
 665                 // See http://bugs.php.net/bug.php?id=36514
 666                 ob_start();
 667
 668                 // Find out which modules are missing and instantiate the others
 669                 $modules = array();
 670                 $missing = array();
 671                 foreach ( $context->getModules() as $name ) {
 672                         $module = $this->getModule( $name );
 673                         if ( $module ) {
 674                                 // Do not allow private modules to be loaded from the web.
 675                                 // This is a security issue, see bug 34907.
 676                                 if ( $module->getGroup() === 'private' ) {
 677                                         $this->logger->debug( "Request for private module '$name' denied" );
 678                                         $this->errors[] = "Cannot show private module \"$name\"";
 679                                         continue;
 680                                 }
 681                                 $modules[$name] = $module;
 682                         } else {
 683                                 $missing[] = $name;
 684                         }
 685                 }
 686
 687                 try {
 688                         // Preload for getCombinedVersion()
 689                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 690                 } catch ( Exception $e ) {
 691                         MWExceptionHandler::logException( $e );
 692                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 693                                 'exception' => $e
 694                         ) );
 695                         $this->errors[] = self::formatExceptionNoComment( $e );
 696                 }
 697
 698                 // Combine versions to propagate cache invalidation
 699                 $versionHash = '';
 700                 try {
 701                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 702                 } catch ( Exception $e ) {
 703                         MWExceptionHandler::logException( $e );
 704                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 705                                 'exception' => $e
 706                         ) );
 707                         $this->errors[] = self::formatExceptionNoComment( $e );
 708                 }
 709
 710                 // See RFC 2616 § 3.11 Entity Tags
 711                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 712                 $etag = 'W/"' . $versionHash . '"';
 713
 714                 // Try the client-side cache first
 715                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 716                         return; // output handled (buffers cleared)
 717                 }
 718
 719                 // Use file cache if enabled and available...
 720                 if ( $this->config->get( 'UseFileCache' ) ) {
 721                         $fileCache = ResourceFileCache::newFromContext( $context );
 722                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 723                                 return; // output handled
 724                         }
 725                 }
 726
 727                 // Generate a response
 728                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 729
 730                 // Capture any PHP warnings from the output buffer and append them to the
 731                 // error list if we're in debug mode.
 732                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 733                         $this->errors[] = $warnings;
 734                 }
 735
 736                 // Save response to file cache unless there are errors
 737                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 738                         // Cache single modules and images...and other requests if there are enough hits
 739                         if ( ResourceFileCache::useFileCache( $context ) ) {
 740                                 if ( $fileCache->isCacheWorthy() ) {
 741                                         $fileCache->saveText( $response );
 742                                 } else {
 743                                         $fileCache->incrMissesRecent( $context->getRequest() );
 744                                 }
 745                         }
 746                 }
 747
 748                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 749
 750                 // Remove the output buffer and output the response
 751                 ob_end_clean();
 752
 753                 if ( $context->getImageObj() && $this->errors ) {
 754                         // We can't show both the error messages and the response when it's an image.
 755                         $response = implode( "\n\n", $this->errors );
 756                 } elseif ( $this->errors ) {
 757                         $errorText = implode( "\n\n", $this->errors );
 758                         $errorResponse = self::makeComment( $errorText );
 759                         if ( $context->shouldIncludeScripts() ) {
 760                                 $errorResponse .= 'if (window.console && console.error) {'
 761                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 762                                         . "}\n";
 763                         }
 764
 765                         // Prepend error info to the response
 766                         $response = $errorResponse . $response;
 767                 }
 768
 769                 $this->errors = array();
 770                 echo $response;
 771
 772         }
 773
 774         /**
 775          * Send main response headers to the client.
 776          *
 777          * Deals with Content-Type, CORS (for stylesheets), and caching.
 778          *
 779          * @param ResourceLoaderContext $context
 780          * @param string $etag ETag header value
 781          * @param bool $errors Whether there are errors in the response
 782          * @return void
 783          */
 784         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 785                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 786                 // If a version wasn't specified we need a shorter expiry time for updates
 787                 // to propagate to clients quickly
 788                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 789                 if ( is_null( $context->getVersion() ) || $errors ) {
 790                         $maxage = $rlMaxage['unversioned']['client'];
 791                         $smaxage = $rlMaxage['unversioned']['server'];
 792                 // If a version was specified we can use a longer expiry time since changing
 793                 // version numbers causes cache misses
 794                 } else {
 795                         $maxage = $rlMaxage['versioned']['client'];
 796                         $smaxage = $rlMaxage['versioned']['server'];
 797                 }
 798                 if ( $context->getImageObj() ) {
 799                         // Output different headers if we're outputting textual errors.
 800                         if ( $errors ) {
 801                                 header( 'Content-Type: text/plain; charset=utf-8' );
 802                         } else {
 803                                 $context->getImageObj()->sendResponseHeaders( $context );
 804                         }
 805                 } elseif ( $context->getOnly() === 'styles' ) {
 806                         header( 'Content-Type: text/css; charset=utf-8' );
 807                         header( 'Access-Control-Allow-Origin: *' );
 808                 } else {
 809                         header( 'Content-Type: text/javascript; charset=utf-8' );
 810                 }
 811                 // See RFC 2616 § 14.19 ETag
 812                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 813                 header( 'ETag: ' . $etag );
 814                 if ( $context->getDebug() ) {
 815                         // Do not cache debug responses
 816                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 817                         header( 'Pragma: no-cache' );
 818                 } else {
 819                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 820                         $exp = min( $maxage, $smaxage );
 821                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 822                 }
 823
 824                 // Send the current time expressed as fractional seconds since epoch,
 825                 // with microsecond precision. This helps distinguish hits from misses
 826                 // in edge caches.
 827                 header( 'MediaWiki-Timestamp: ' . microtime( true ) );
 828         }
 829
 830         /**
 831          * Respond with HTTP 304 Not Modified if appropiate.
 832          *
 833          * If there's an If-None-Match header, respond with a 304 appropriately
 834          * and clear out the output buffer. If the client cache is too old then do nothing.
 835          *
 836          * @param ResourceLoaderContext $context
 837          * @param string $etag ETag header value
 838          * @return bool True if HTTP 304 was sent and output handled
 839          */
 840         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 841                 // See RFC 2616 § 14.26 If-None-Match
 842                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 843                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 844                 // Never send 304s in debug mode
 845                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 846                         // There's another bug in ob_gzhandler (see also the comment at
 847                         // the top of this function) that causes it to gzip even empty
 848                         // responses, meaning it's impossible to produce a truly empty
 849                         // response (because the gzip header is always there). This is
 850                         // a problem because 304 responses have to be completely empty
 851                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 852                         // See also http://bugs.php.net/bug.php?id=51579
 853                         // To work around this, we tear down all output buffering before
 854                         // sending the 304.
 855                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 856
 857                         HttpStatus::header( 304 );
 858
 859                         $this->sendResponseHeaders( $context, $etag, false );
 860                         return true;
 861                 }
 862                 return false;
 863         }
 864
 865         /**
 866          * Send out code for a response from file cache if possible.
 867          *
 868          * @param ResourceFileCache $fileCache Cache object for this request URL
 869          * @param ResourceLoaderContext $context Context in which to generate a response
 870          * @param string $etag ETag header value
 871          * @return bool If this found a cache file and handled the response
 872          */
 873         protected function tryRespondFromFileCache(
 874                 ResourceFileCache $fileCache,
 875                 ResourceLoaderContext $context,
 876                 $etag
 877         ) {
 878                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 879                 // Buffer output to catch warnings.
 880                 ob_start();
 881                 // Get the maximum age the cache can be
 882                 $maxage = is_null( $context->getVersion() )
 883                         ? $rlMaxage['unversioned']['server']
 884                         : $rlMaxage['versioned']['server'];
 885                 // Minimum timestamp the cache file must have
 886                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 887                 if ( !$good ) {
 888                         try { // RL always hits the DB on file cache miss...
 889                                 wfGetDB( DB_SLAVE );
 890                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 891                                 $good = $fileCache->isCacheGood(); // cache existence check
 892                         }
 893                 }
 894                 if ( $good ) {
 895                         $ts = $fileCache->cacheTimestamp();
 896                         // Send content type and cache headers
 897                         $this->sendResponseHeaders( $context, $etag, false );
 898                         $response = $fileCache->fetchText();
 899                         // Capture any PHP warnings from the output buffer and append them to the
 900                         // response in a comment if we're in debug mode.
 901                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 902                                 $response = self::makeComment( $warnings ) . $response;
 903                         }
 904                         // Remove the output buffer and output the response
 905                         ob_end_clean();
 906                         echo $response . "\n/* Cached {$ts} */";
 907                         return true; // cache hit
 908                 }
 909                 // Clear buffer
 910                 ob_end_clean();
 911
 912                 return false; // cache miss
 913         }
 914
 915         /**
 916          * Generate a CSS or JS comment block.
 917          *
 918          * Only use this for public data, not error message details.
 919          *
 920          * @param string $text
 921          * @return string
 922          */
 923         public static function makeComment( $text ) {
 924                 $encText = str_replace( '*/', '* /', $text );
 925                 return "/*\n$encText\n*/\n";
 926         }
 927
 928         /**
 929          * Handle exception display.
 930          *
 931          * @param Exception $e Exception to be shown to the user
 932          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 933          */
 934         public static function formatException( $e ) {
 935                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 936         }
 937
 938         /**
 939          * Handle exception display.
 940          *
 941          * @since 1.25
 942          * @param Exception $e Exception to be shown to the user
 943          * @return string Sanitized text that can be returned to the user
 944          */
 945         protected static function formatExceptionNoComment( $e ) {
 946                 global $wgShowExceptionDetails;
 947
 948                 if ( !$wgShowExceptionDetails ) {
 949                         return MWExceptionHandler::getPublicLogMessage( $e );
 950                 }
 951
 952                 return MWExceptionHandler::getLogMessage( $e );
 953         }
 954
 955         /**
 956          * Generate code for a response.
 957          *
 958          * @param ResourceLoaderContext $context Context in which to generate a response
 959          * @param array $modules List of module objects keyed by module name
 960          * @param array $missing List of requested module names that are unregistered (optional)
 961          * @return string Response data
 962          */
 963         public function makeModuleResponse( ResourceLoaderContext $context,
 964                 array $modules, array $missing = array()
 965         ) {
 966                 $out = '';
 967                 $states = array();
 968
 969                 if ( !count( $modules ) && !count( $missing ) ) {
 970                         return <<<MESSAGE
 971 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 972    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 973    no modules were requested. Max made me put this here. */
 974 MESSAGE;
 975                 }
 976
 977                 $image = $context->getImageObj();
 978                 if ( $image ) {
 979                         $data = $image->getImageData( $context );
 980                         if ( $data === false ) {
 981                                 $data = '';
 982                                 $this->errors[] = 'Image generation failed';
 983                         }
 984                         return $data;
 985                 }
 986
 987                 // Pre-fetch blobs
 988                 if ( $context->shouldIncludeMessages() ) {
 989                         try {
 990                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 991                         } catch ( Exception $e ) {
 992                                 MWExceptionHandler::logException( $e );
 993                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 994                                         'exception' => $e
 995                                 ) );
 996                                 $this->errors[] = self::formatExceptionNoComment( $e );
 997                         }
 998                 }
 999
1000                 foreach ( $missing as $name ) {
1001                         $states[$name] = 'missing';
1002                 }
1003
1004                 // Generate output
1005                 $isRaw = false;
1006                 foreach ( $modules as $name => $module ) {
1007                         try {
1008                                 $content = $module->getModuleContent( $context );
1009
1010                                 // Append output
1011                                 switch ( $context->getOnly() ) {
1012                                         case 'scripts':
1013                                                 $scripts = $content['scripts'];
1014                                                 if ( is_string( $scripts ) ) {
1015                                                         // Load scripts raw...
1016                                                         $out .= $scripts;
1017                                                 } elseif ( is_array( $scripts ) ) {
1018                                                         // ...except when $scripts is an array of URLs
1019                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
1020                                                 }
1021                                                 break;
1022                                         case 'styles':
1023                                                 $styles = $content['styles'];
1024                                                 // We no longer seperate into media, they are all combined now with
1025                                                 // custom media type groups into @media .. {} sections as part of the css string.
1026                                                 // Module returns either an empty array or a numerical array with css strings.
1027                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1028                                                 break;
1029                                         default:
1030                                                 $out .= self::makeLoaderImplementScript(
1031                                                         $name,
1032                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1033                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1034                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1035                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1036                                                 );
1037                                                 break;
1038                                 }
1039                         } catch ( Exception $e ) {
1040                                 MWExceptionHandler::logException( $e );
1041                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1042                                         'exception' => $e
1043                                 ) );
1044                                 $this->errors[] = self::formatExceptionNoComment( $e );
1045
1046                                 // Respond to client with error-state instead of module implementation
1047                                 $states[$name] = 'error';
1048                                 unset( $modules[$name] );
1049                         }
1050                         $isRaw |= $module->isRaw();
1051                 }
1052
1053                 // Update module states
1054                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1055                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1056                                 // Set the state of modules loaded as only scripts to ready as
1057                                 // they don't have an mw.loader.implement wrapper that sets the state
1058                                 foreach ( $modules as $name => $module ) {
1059                                         $states[$name] = 'ready';
1060                                 }
1061                         }
1062
1063                         // Set the state of modules we didn't respond to with mw.loader.implement
1064                         if ( count( $states ) ) {
1065                                 $out .= self::makeLoaderStateScript( $states );
1066                         }
1067                 } else {
1068                         if ( count( $states ) ) {
1069                                 $this->errors[] = 'Problematic modules: ' .
1070                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1071                         }
1072                 }
1073
1074                 $enableFilterCache = true;
1075                 if ( count( $modules ) === 1 && reset( $modules ) instanceof ResourceLoaderUserTokensModule ) {
1076                         // If we're building the embedded user.tokens, don't cache (T84960)
1077                         $enableFilterCache = false;
1078                 }
1079
1080                 if ( !$context->getDebug() ) {
1081                         if ( $context->getOnly() === 'styles' ) {
1082                                 $out = $this->filter( 'minify-css', $out );
1083                         } else {
1084                                 $out = $this->filter( 'minify-js', $out, array(
1085                                         'cache' => $enableFilterCache
1086                                 ) );
1087                         }
1088                 }
1089
1090                 return $out;
1091         }
1092
1093         /* Static Methods */
1094
1095         /**
1096          * Return JS code that calls mw.loader.implement with given module properties.
1097          *
1098          * @param string $name Module name
1099          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1100          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1101          *   to CSS files keyed by media type
1102          * @param mixed $messages List of messages associated with this module. May either be an
1103          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1104          *   the same data, wrapped in an XmlJsCode object.
1105          * @param array $templates Keys are name of templates and values are the source of
1106          *   the template.
1107          * @throws MWException
1108          * @return string
1109          */
1110         public static function makeLoaderImplementScript(
1111                 $name, $scripts, $styles, $messages, $templates
1112         ) {
1113                 if ( is_string( $scripts ) ) {
1114                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1115                         // Transportation as string instructs mw.loader.implement to use globalEval.
1116                         if ( $name === 'site' || $name === 'user' ) {
1117                                 // Minify manually because the general makeModuleResponse() minification won't be
1118                                 // effective here due to the script being a string instead of a function. (T107377)
1119                                 if ( !ResourceLoader::inDebugMode() ) {
1120                                         $scripts = self::applyFilter( 'minify-js', $scripts,
1121                                                 ConfigFactory::getDefaultInstance()->makeConfig( 'main' ) );
1122                                 }
1123                         } else {
1124                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1125                         }
1126                 } elseif ( !is_array( $scripts ) ) {
1127                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1128                 }
1129                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1130                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1131                 // of "{}". Force them to objects.
1132                 $module = array(
1133                         $name,
1134                         $scripts,
1135                         (object)$styles,
1136                         (object)$messages,
1137                         (object)$templates,
1138                 );
1139                 self::trimArray( $module );
1140
1141                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1142         }
1143
1144         /**
1145          * Returns JS code which, when called, will register a given list of messages.
1146          *
1147          * @param mixed $messages Either an associative array mapping message key to value, or a
1148          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1149          * @return string
1150          */
1151         public static function makeMessageSetScript( $messages ) {
1152                 return Xml::encodeJsCall(
1153                         'mw.messages.set',
1154                         array( (object)$messages ),
1155                         ResourceLoader::inDebugMode()
1156                 );
1157         }
1158
1159         /**
1160          * Combines an associative array mapping media type to CSS into a
1161          * single stylesheet with "@media" blocks.
1162          *
1163          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1164          * @return array
1165          */
1166         public static function makeCombinedStyles( array $stylePairs ) {
1167                 $out = array();
1168                 foreach ( $stylePairs as $media => $styles ) {
1169                         // ResourceLoaderFileModule::getStyle can return the styles
1170                         // as a string or an array of strings. This is to allow separation in
1171                         // the front-end.
1172                         $styles = (array)$styles;
1173                         foreach ( $styles as $style ) {
1174                                 $style = trim( $style );
1175                                 // Don't output an empty "@media print { }" block (bug 40498)
1176                                 if ( $style !== '' ) {
1177                                         // Transform the media type based on request params and config
1178                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1179                                         $media = OutputPage::transformCssMedia( $media );
1180
1181                                         if ( $media === '' || $media == 'all' ) {
1182                                                 $out[] = $style;
1183                                         } elseif ( is_string( $media ) ) {
1184                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1185                                         }
1186                                         // else: skip
1187                                 }
1188                         }
1189                 }
1190                 return $out;
1191         }
1192
1193         /**
1194          * Returns a JS call to mw.loader.state, which sets the state of a
1195          * module or modules to a given value. Has two calling conventions:
1196          *
1197          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1198          *         Set the state of a single module called $name to $state
1199          *
1200          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1201          *         Set the state of modules with the given names to the given states
1202          *
1203          * @param string $name
1204          * @param string $state
1205          * @return string
1206          */
1207         public static function makeLoaderStateScript( $name, $state = null ) {
1208                 if ( is_array( $name ) ) {
1209                         return Xml::encodeJsCall(
1210                                 'mw.loader.state',
1211                                 array( $name ),
1212                                 ResourceLoader::inDebugMode()
1213                         );
1214                 } else {
1215                         return Xml::encodeJsCall(
1216                                 'mw.loader.state',
1217                                 array( $name, $state ),
1218                                 ResourceLoader::inDebugMode()
1219                         );
1220                 }
1221         }
1222
1223         /**
1224          * Returns JS code which calls the script given by $script. The script will
1225          * be called with local variables name, version, dependencies and group,
1226          * which will have values corresponding to $name, $version, $dependencies
1227          * and $group as supplied.
1228          *
1229          * @param string $name Module name
1230          * @param string $version Module version hash
1231          * @param array $dependencies List of module names on which this module depends
1232          * @param string $group Group which the module is in.
1233          * @param string $source Source of the module, or 'local' if not foreign.
1234          * @param string $script JavaScript code
1235          * @return string
1236          */
1237         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1238                 $group, $source, $script
1239         ) {
1240                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1241                 return Xml::encodeJsCall(
1242                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1243                         array( $name, $version, $dependencies, $group, $source ),
1244                         ResourceLoader::inDebugMode()
1245                 );
1246         }
1247
1248         private static function isEmptyObject( stdClass $obj ) {
1249                 foreach ( $obj as $key => &$value ) {
1250                         return false;
1251                 }
1252                 return true;
1253         }
1254
1255         /**
1256          * Remove empty values from the end of an array.
1257          *
1258          * Values considered empty:
1259          *
1260          * - null
1261          * - array()
1262          * - new XmlJsCode( '{}' )
1263          * - new stdClass() // (object) array()
1264          *
1265          * @param Array $array
1266          */
1267         private static function trimArray( Array &$array ) {
1268                 $i = count( $array );
1269                 while ( $i-- ) {
1270                         if ( $array[$i] === null
1271                                 || $array[$i] === array()
1272                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1273                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1274                         ) {
1275                                 unset( $array[$i] );
1276                         } else {
1277                                 break;
1278                         }
1279                 }
1280         }
1281
1282         /**
1283          * Returns JS code which calls mw.loader.register with the given
1284          * parameters. Has three calling conventions:
1285          *
1286          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1287          *        $dependencies, $group, $source, $skip
1288          *     ):
1289          *        Register a single module.
1290          *
1291          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1292          *        Register modules with the given names.
1293          *
1294          *   - ResourceLoader::makeLoaderRegisterScript( array(
1295          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1296          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1297          *        ...
1298          *     ) ):
1299          *        Registers modules with the given names and parameters.
1300          *
1301          * @param string $name Module name
1302          * @param string $version Module version hash
1303          * @param array $dependencies List of module names on which this module depends
1304          * @param string $group Group which the module is in
1305          * @param string $source Source of the module, or 'local' if not foreign
1306          * @param string $skip Script body of the skip function
1307          * @return string
1308          */
1309         public static function makeLoaderRegisterScript( $name, $version = null,
1310                 $dependencies = null, $group = null, $source = null, $skip = null
1311         ) {
1312                 if ( is_array( $name ) ) {
1313                         // Build module name index
1314                         $index = array();
1315                         foreach ( $name as $i => &$module ) {
1316                                 $index[$module[0]] = $i;
1317                         }
1318
1319                         // Transform dependency names into indexes when possible, they will be resolved by
1320                         // mw.loader.register on the other end
1321                         foreach ( $name as &$module ) {
1322                                 if ( isset( $module[2] ) ) {
1323                                         foreach ( $module[2] as &$dependency ) {
1324                                                 if ( isset( $index[$dependency] ) ) {
1325                                                         $dependency = $index[$dependency];
1326                                                 }
1327                                         }
1328                                 }
1329                         }
1330
1331                         array_walk( $name, array( 'self', 'trimArray' ) );
1332
1333                         return Xml::encodeJsCall(
1334                                 'mw.loader.register',
1335                                 array( $name ),
1336                                 ResourceLoader::inDebugMode()
1337                         );
1338                 } else {
1339                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1340                         self::trimArray( $registration );
1341                         return Xml::encodeJsCall(
1342                                 'mw.loader.register',
1343                                 $registration,
1344                                 ResourceLoader::inDebugMode()
1345                         );
1346                 }
1347         }
1348
1349         /**
1350          * Returns JS code which calls mw.loader.addSource() with the given
1351          * parameters. Has two calling conventions:
1352          *
1353          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1354          *       Register a single source
1355          *
1356          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1357          *       Register sources with the given IDs and properties.
1358          *
1359          * @param string $id Source ID
1360          * @param array $properties Source properties (see addSource())
1361          * @return string
1362          */
1363         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1364                 if ( is_array( $id ) ) {
1365                         return Xml::encodeJsCall(
1366                                 'mw.loader.addSource',
1367                                 array( $id ),
1368                                 ResourceLoader::inDebugMode()
1369                         );
1370                 } else {
1371                         return Xml::encodeJsCall(
1372                                 'mw.loader.addSource',
1373                                 array( $id, $properties ),
1374                                 ResourceLoader::inDebugMode()
1375                         );
1376                 }
1377         }
1378
1379         /**
1380          * Returns JS code which runs given JS code if the client-side framework is
1381          * present.
1382          *
1383          * @deprecated since 1.25; use makeInlineScript instead
1384          * @param string $script JavaScript code
1385          * @return string
1386          */
1387         public static function makeLoaderConditionalScript( $script ) {
1388                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1389                         trim( $script ) . "\n} );";
1390         }
1391
1392         /**
1393          * Construct an inline script tag with given JS code.
1394          *
1395          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1396          * only if the client has adequate support for MediaWiki JavaScript code.
1397          *
1398          * @param string $script JavaScript code
1399          * @return WrappedString HTML
1400          */
1401         public static function makeInlineScript( $script ) {
1402                 $js = self::makeLoaderConditionalScript( $script );
1403                 return new WrappedString(
1404                         Html::inlineScript( $js ),
1405                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1406                         "\n} );</script>"
1407                 );
1408         }
1409
1410         /**
1411          * Returns JS code which will set the MediaWiki configuration array to
1412          * the given value.
1413          *
1414          * @param array $configuration List of configuration values keyed by variable name
1415          * @return string
1416          */
1417         public static function makeConfigSetScript( array $configuration ) {
1418                 if ( ResourceLoader::inDebugMode() ) {
1419                         return Xml::encodeJsCall( 'mw.config.set', array( $configuration ), true );
1420                 }
1421
1422                 $config = RequestContext::getMain()->getConfig();
1423                 $js = Xml::encodeJsCall( 'mw.config.set', array( $configuration ), false );
1424                 return self::applyFilter( 'minify-js', $js, $config );
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, too.
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                 return wfAppendQuery( $script, $query );
1495         }
1496
1497         /**
1498          * Build a load.php URL
1499          * @deprecated since 1.24 Use createLoaderURL() instead
1500          * @param array $modules Array of module names (strings)
1501          * @param string $lang Language code
1502          * @param string $skin Skin name
1503          * @param string|null $user User name. If null, the &user= parameter is omitted
1504          * @param string|null $version Versioning timestamp
1505          * @param bool $debug Whether the request should be in debug mode
1506          * @param string|null $only &only= parameter
1507          * @param bool $printable Printable mode
1508          * @param bool $handheld Handheld mode
1509          * @param array $extraQuery Extra query parameters to add
1510          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1511          */
1512         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1513                 $version = null, $debug = false, $only = null, $printable = false,
1514                 $handheld = false, $extraQuery = array()
1515         ) {
1516                 global $wgLoadScript;
1517
1518                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1519                         $only, $printable, $handheld, $extraQuery
1520                 );
1521
1522                 return wfAppendQuery( $wgLoadScript, $query );
1523         }
1524
1525         /**
1526          * Helper for createLoaderURL()
1527          *
1528          * @since 1.24
1529          * @see makeLoaderQuery
1530          * @param ResourceLoaderContext $context
1531          * @param array $extraQuery
1532          * @return array
1533          */
1534         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1535                 return self::makeLoaderQuery(
1536                         $context->getModules(),
1537                         $context->getLanguage(),
1538                         $context->getSkin(),
1539                         $context->getUser(),
1540                         $context->getVersion(),
1541                         $context->getDebug(),
1542                         $context->getOnly(),
1543                         $context->getRequest()->getBool( 'printable' ),
1544                         $context->getRequest()->getBool( 'handheld' ),
1545                         $extraQuery
1546                 );
1547         }
1548
1549         /**
1550          * Build a query array (array representation of query string) for load.php. Helper
1551          * function for makeLoaderURL().
1552          *
1553          * @param array $modules
1554          * @param string $lang
1555          * @param string $skin
1556          * @param string $user
1557          * @param string $version
1558          * @param bool $debug
1559          * @param string $only
1560          * @param bool $printable
1561          * @param bool $handheld
1562          * @param array $extraQuery
1563          *
1564          * @return array
1565          */
1566         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1567                 $version = null, $debug = false, $only = null, $printable = false,
1568                 $handheld = false, $extraQuery = array()
1569         ) {
1570                 $query = array(
1571                         'modules' => self::makePackedModulesString( $modules ),
1572                         'lang' => $lang,
1573                         'skin' => $skin,
1574                         'debug' => $debug ? 'true' : 'false',
1575                 );
1576                 if ( $user !== null ) {
1577                         $query['user'] = $user;
1578                 }
1579                 if ( $version !== null ) {
1580                         $query['version'] = $version;
1581                 }
1582                 if ( $only !== null ) {
1583                         $query['only'] = $only;
1584                 }
1585                 if ( $printable ) {
1586                         $query['printable'] = 1;
1587                 }
1588                 if ( $handheld ) {
1589                         $query['handheld'] = 1;
1590                 }
1591                 $query += $extraQuery;
1592
1593                 // Make queries uniform in order
1594                 ksort( $query );
1595                 return $query;
1596         }
1597
1598         /**
1599          * Check a module name for validity.
1600          *
1601          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1602          * at most 255 bytes.
1603          *
1604          * @param string $moduleName Module name to check
1605          * @return bool Whether $moduleName is a valid module name
1606          */
1607         public static function isValidModuleName( $moduleName ) {
1608                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1609         }
1610
1611         /**
1612          * Returns LESS compiler set up for use with MediaWiki
1613          *
1614          * @param Config $config
1615          * @throws MWException
1616          * @since 1.22
1617          * @return Less_Parser
1618          */
1619         public static function getLessCompiler( Config $config ) {
1620                 // When called from the installer, it is possible that a required PHP extension
1621                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1622                 // exception (caught by the installer) to prevent a fatal error later on.
1623                 if ( !class_exists( 'Less_Parser' ) ) {
1624                         throw new MWException( 'MediaWiki requires the less.php parser' );
1625                 }
1626
1627                 $parser = new Less_Parser;
1628                 $parser->ModifyVars( self::getLessVars( $config ) );
1629                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1630                 $parser->SetOption( 'relativeUrls', false );
1631                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1632
1633                 return $parser;
1634         }
1635
1636         /**
1637          * Get global LESS variables.
1638          *
1639          * @param Config $config
1640          * @since 1.22
1641          * @return array Map of variable names to string CSS values.
1642          */
1643         public static function getLessVars( Config $config ) {
1644                 if ( !self::$lessVars ) {
1645                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1646                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1647                         // Sort by key to ensure consistent hashing for cache lookups.
1648                         ksort( $lessVars );
1649                         self::$lessVars = $lessVars;
1650                 }
1651                 return self::$lessVars;
1652         }
1653 }