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                 // Batched version of ResourceLoaderModule::getFileDependencies
 114                 $vary = "$skin|$lang";
 115                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 116                                 'md_module' => $modules,
 117                                 'md_skin' => $vary,
 118                         ), __METHOD__
 119                 );
 120                 // Prime in-object cache values for each module
 121                 $modulesWithDeps = array();
 122                 foreach ( $res as $row ) {
 123                         $module = $this->getModule( $row->md_module );
 124                         if ( $module ) {
 125                                 $module->setFileDependencies( $context, ResourceLoader::expandRelativePaths(
 126                                         FormatJson::decode( $row->md_deps, true )
 127                                 ) );
 128                                 $modulesWithDeps[] = $row->md_module;
 129                         }
 130                 }
 131                 // Register the absence of a dependency row too
 132                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 133                         $module = $this->getModule( $name );
 134                         if ( $module ) {
 135                                 $this->getModule( $name )->setFileDependencies( $context, array() );
 136                         }
 137                 }
 138
 139                 // Get message blob mtimes. Only do this for modules with messages
 140                 $modulesWithMessages = array();
 141                 foreach ( $modules as $name ) {
 142                         $module = $this->getModule( $name );
 143                         if ( $module && count( $module->getMessages() ) ) {
 144                                 $modulesWithMessages[] = $name;
 145                         }
 146                 }
 147                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 148                 if ( count( $modulesWithMessages ) ) {
 149                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 150                                         'mr_resource' => $modulesWithMessages,
 151                                         'mr_lang' => $lang
 152                                 ), __METHOD__
 153                         );
 154                         foreach ( $res as $row ) {
 155                                 $module = $this->getModule( $row->mr_resource );
 156                                 if ( $module ) {
 157                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 158                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 159                                 }
 160                         }
 161                 }
 162                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 163                         $module = $this->getModule( $name );
 164                         if ( $module ) {
 165                                 $module->setMsgBlobMtime( $lang, 1 );
 166                         }
 167                 }
 168         }
 169
 170         /**
 171          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 172          *
 173          * Available filters are:
 174          *
 175          *    - minify-js \see JavaScriptMinifier::minify
 176          *    - minify-css \see CSSMin::minify
 177          *
 178          * If $data is empty, only contains whitespace or the filter was unknown,
 179          * $data is returned unmodified.
 180          *
 181          * @param string $filter Name of filter to run
 182          * @param string $data Text to filter, such as JavaScript or CSS text
 183          * @param array $options For back-compat, can also be the boolean value for "cacheReport". Keys:
 184          *  - (bool) cache: Whether to allow caching this data. Default: true.
 185          *  - (bool) cacheReport: Whether to include the "cache key" report comment. Default: false.
 186          * @return string Filtered data, or a comment containing an error message
 187          */
 188         public function filter( $filter, $data, $options = array() ) {
 189                 // Back-compat
 190                 if ( is_bool( $options ) ) {
 191                         $options = array( 'cacheReport' => $options );
 192                 }
 193                 // Defaults
 194                 $options += array( 'cache' => true, 'cacheReport' => false );
 195                 $stats = RequestContext::getMain()->getStats();
 196
 197                 // Don't filter empty content
 198                 if ( trim( $data ) === '' ) {
 199                         return $data;
 200                 }
 201
 202                 if ( !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 203                         $this->logger->warning( 'Invalid filter {filter}', array(
 204                                 'filter' => $filter
 205                         ) );
 206                         return $data;
 207                 }
 208
 209                 if ( !$options['cache'] ) {
 210                         $result = self::applyFilter( $filter, $data, $this->config );
 211                 } else {
 212                         $key = wfGlobalCacheKey(
 213                                 'resourceloader',
 214                                 'filter',
 215                                 $filter,
 216                                 self::$filterCacheVersion, md5( $data )
 217                         );
 218                         $cache = wfGetCache( wfIsHHVM() ? CACHE_ACCEL : CACHE_ANYTHING );
 219                         $cacheEntry = $cache->get( $key );
 220                         if ( is_string( $cacheEntry ) ) {
 221                                 $stats->increment( "resourceloader_cache.$filter.hit" );
 222                                 return $cacheEntry;
 223                         }
 224                         $result = '';
 225                         try {
 226                                 $statStart = microtime( true );
 227                                 $result = self::applyFilter( $filter, $data, $this->config );
 228                                 $statTiming = microtime( true ) - $statStart;
 229                                 $stats->increment( "resourceloader_cache.$filter.miss" );
 230                                 $stats->timing( "resourceloader_cache.$filter.timing", 1000 * $statTiming );
 231                                 if ( $options['cacheReport'] ) {
 232                                         $result .= "\n/* cache key: $key */";
 233                                 }
 234                                 // Set a TTL since HHVM's APC doesn't have any limitation or eviction logic.
 235                                 $cache->set( $key, $result, 24 * 3600 );
 236                         } catch ( Exception $e ) {
 237                                 MWExceptionHandler::logException( $e );
 238                                 $this->logger->warning( 'Minification failed: {exception}', array(
 239                                         'exception' => $e
 240                                 ) );
 241                                 $this->errors[] = self::formatExceptionNoComment( $e );
 242                         }
 243                 }
 244
 245                 return $result;
 246         }
 247
 248         private static function applyFilter( $filter, $data, Config $config ) {
 249                 switch ( $filter ) {
 250                         case 'minify-js':
 251                                 return JavaScriptMinifier::minify( $data );
 252                         case 'minify-css':
 253                                 return CSSMin::minify( $data );
 254                 }
 255
 256                 return $data;
 257         }
 258
 259         /* Methods */
 260
 261         /**
 262          * Register core modules and runs registration hooks.
 263          * @param Config|null $config
 264          */
 265         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 266                 global $IP;
 267
 268                 if ( !$logger ) {
 269                         $logger = new NullLogger();
 270                 }
 271                 $this->setLogger( $logger );
 272
 273                 if ( !$config ) {
 274                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 275                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 276                 }
 277                 $this->config = $config;
 278
 279                 // Add 'local' source first
 280                 $this->addSource( 'local', wfScript( 'load' ) );
 281
 282                 // Add other sources
 283                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 284
 285                 // Register core modules
 286                 $this->register( include "$IP/resources/Resources.php" );
 287                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 288                 // Register extension modules
 289                 $this->register( $config->get( 'ResourceModules' ) );
 290                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 291
 292                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 293                         $this->registerTestModules();
 294                 }
 295
 296                 $this->setMessageBlobStore( new MessageBlobStore() );
 297         }
 298
 299         /**
 300          * @return Config
 301          */
 302         public function getConfig() {
 303                 return $this->config;
 304         }
 305
 306         public function setLogger( LoggerInterface $logger ) {
 307                 $this->logger = $logger;
 308         }
 309
 310         /**
 311          * @since 1.26
 312          * @return MessageBlobStore
 313          */
 314         public function getMessageBlobStore() {
 315                 return $this->blobStore;
 316         }
 317
 318         /**
 319          * @since 1.25
 320          * @param MessageBlobStore $blobStore
 321          */
 322         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 323                 $this->blobStore = $blobStore;
 324         }
 325
 326         /**
 327          * Register a module with the ResourceLoader system.
 328          *
 329          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 330          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 331          *   this may also be a ResourceLoaderModule object. Optional when using
 332          *   multiple-registration calling style.
 333          * @throws MWException If a duplicate module registration is attempted
 334          * @throws MWException If a module name contains illegal characters (pipes or commas)
 335          * @throws MWException If something other than a ResourceLoaderModule is being registered
 336          * @return bool False if there were any errors, in which case one or more modules were
 337          *   not registered
 338          */
 339         public function register( $name, $info = null ) {
 340
 341                 // Allow multiple modules to be registered in one call
 342                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 343                 foreach ( $registrations as $name => $info ) {
 344                         // Disallow duplicate registrations
 345                         if ( isset( $this->moduleInfos[$name] ) ) {
 346                                 // A module has already been registered by this name
 347                                 throw new MWException(
 348                                         'ResourceLoader duplicate registration error. ' .
 349                                         'Another module has already been registered as ' . $name
 350                                 );
 351                         }
 352
 353                         // Check $name for validity
 354                         if ( !self::isValidModuleName( $name ) ) {
 355                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 356                                         . "see ResourceLoader::isValidModuleName()" );
 357                         }
 358
 359                         // Attach module
 360                         if ( $info instanceof ResourceLoaderModule ) {
 361                                 $this->moduleInfos[$name] = array( 'object' => $info );
 362                                 $info->setName( $name );
 363                                 $this->modules[$name] = $info;
 364                         } elseif ( is_array( $info ) ) {
 365                                 // New calling convention
 366                                 $this->moduleInfos[$name] = $info;
 367                         } else {
 368                                 throw new MWException(
 369                                         'ResourceLoader module info type error for module \'' . $name .
 370                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 371                                 );
 372                         }
 373
 374                         // Last-minute changes
 375
 376                         // Apply custom skin-defined styles to existing modules.
 377                         if ( $this->isFileModule( $name ) ) {
 378                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 379                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 380                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 381                                                 continue;
 382                                         }
 383
 384                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 385                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 386                                         if ( isset( $skinStyles[$name] ) ) {
 387                                                 $paths = (array)$skinStyles[$name];
 388                                                 $styleFiles = array();
 389                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 390                                                 $paths = (array)$skinStyles['+' . $name];
 391                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 392                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 393                                                         array();
 394                                         } else {
 395                                                 continue;
 396                                         }
 397
 398                                         // Add new file paths, remapping them to refer to our directories and not use settings
 399                                         // from the module we're modifying, which come from the base definition.
 400                                         list( $localBasePath, $remoteBasePath ) =
 401                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 402
 403                                         foreach ( $paths as $path ) {
 404                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 405                                         }
 406
 407                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 408                                 }
 409                         }
 410                 }
 411
 412         }
 413
 414         /**
 415          */
 416         public function registerTestModules() {
 417                 global $IP;
 418
 419                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 420                         throw new MWException( 'Attempt to register JavaScript test modules '
 421                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 422                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 423                 }
 424
 425                 // Get core test suites
 426                 $testModules = array();
 427                 $testModules['qunit'] = array();
 428                 // Get other test suites (e.g. from extensions)
 429                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 430
 431                 // Add the testrunner (which configures QUnit) to the dependencies.
 432                 // Since it must be ready before any of the test suites are executed.
 433                 foreach ( $testModules['qunit'] as &$module ) {
 434                         // Make sure all test modules are top-loading so that when QUnit starts
 435                         // on document-ready, it will run once and finish. If some tests arrive
 436                         // later (possibly after QUnit has already finished) they will be ignored.
 437                         $module['position'] = 'top';
 438                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 439                 }
 440
 441                 $testModules['qunit'] =
 442                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 443
 444                 foreach ( $testModules as $id => $names ) {
 445                         // Register test modules
 446                         $this->register( $testModules[$id] );
 447
 448                         // Keep track of their names so that they can be loaded together
 449                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 450                 }
 451
 452         }
 453
 454         /**
 455          * Add a foreign source of modules.
 456          *
 457          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 458          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 459          *  backwards-compatibility.
 460          * @throws MWException
 461          */
 462         public function addSource( $id, $loadUrl = null ) {
 463                 // Allow multiple sources to be registered in one call
 464                 if ( is_array( $id ) ) {
 465                         foreach ( $id as $key => $value ) {
 466                                 $this->addSource( $key, $value );
 467                         }
 468                         return;
 469                 }
 470
 471                 // Disallow duplicates
 472                 if ( isset( $this->sources[$id] ) ) {
 473                         throw new MWException(
 474                                 'ResourceLoader duplicate source addition error. ' .
 475                                 'Another source has already been registered as ' . $id
 476                         );
 477                 }
 478
 479                 // Pre 1.24 backwards-compatibility
 480                 if ( is_array( $loadUrl ) ) {
 481                         if ( !isset( $loadUrl['loadScript'] ) ) {
 482                                 throw new MWException(
 483                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 484                                 );
 485                         }
 486
 487                         $loadUrl = $loadUrl['loadScript'];
 488                 }
 489
 490                 $this->sources[$id] = $loadUrl;
 491         }
 492
 493         /**
 494          * Get a list of module names.
 495          *
 496          * @return array List of module names
 497          */
 498         public function getModuleNames() {
 499                 return array_keys( $this->moduleInfos );
 500         }
 501
 502         /**
 503          * Get a list of test module names for one (or all) frameworks.
 504          *
 505          * If the given framework id is unknkown, or if the in-object variable is not an array,
 506          * then it will return an empty array.
 507          *
 508          * @param string $framework Get only the test module names for one
 509          *   particular framework (optional)
 510          * @return array
 511          */
 512         public function getTestModuleNames( $framework = 'all' ) {
 513                 /** @todo api siteinfo prop testmodulenames modulenames */
 514                 if ( $framework == 'all' ) {
 515                         return $this->testModuleNames;
 516                 } elseif ( isset( $this->testModuleNames[$framework] )
 517                         && is_array( $this->testModuleNames[$framework] )
 518                 ) {
 519                         return $this->testModuleNames[$framework];
 520                 } else {
 521                         return array();
 522                 }
 523         }
 524
 525         /**
 526          * Check whether a ResourceLoader module is registered
 527          *
 528          * @since 1.25
 529          * @param string $name
 530          * @return bool
 531          */
 532         public function isModuleRegistered( $name ) {
 533                 return isset( $this->moduleInfos[$name] );
 534         }
 535
 536         /**
 537          * Get the ResourceLoaderModule object for a given module name.
 538          *
 539          * If an array of module parameters exists but a ResourceLoaderModule object has not
 540          * yet been instantiated, this method will instantiate and cache that object such that
 541          * subsequent calls simply return the same object.
 542          *
 543          * @param string $name Module name
 544          * @return ResourceLoaderModule|null If module has been registered, return a
 545          *  ResourceLoaderModule instance. Otherwise, return null.
 546          */
 547         public function getModule( $name ) {
 548                 if ( !isset( $this->modules[$name] ) ) {
 549                         if ( !isset( $this->moduleInfos[$name] ) ) {
 550                                 // No such module
 551                                 return null;
 552                         }
 553                         // Construct the requested object
 554                         $info = $this->moduleInfos[$name];
 555                         /** @var ResourceLoaderModule $object */
 556                         if ( isset( $info['object'] ) ) {
 557                                 // Object given in info array
 558                                 $object = $info['object'];
 559                         } else {
 560                                 if ( !isset( $info['class'] ) ) {
 561                                         $class = 'ResourceLoaderFileModule';
 562                                 } else {
 563                                         $class = $info['class'];
 564                                 }
 565                                 /** @var ResourceLoaderModule $object */
 566                                 $object = new $class( $info );
 567                                 $object->setConfig( $this->getConfig() );
 568                         }
 569                         $object->setName( $name );
 570                         $this->modules[$name] = $object;
 571                 }
 572
 573                 return $this->modules[$name];
 574         }
 575
 576         /**
 577          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 578          *
 579          * @param string $name Module name
 580          * @return bool
 581          */
 582         protected function isFileModule( $name ) {
 583                 if ( !isset( $this->moduleInfos[$name] ) ) {
 584                         return false;
 585                 }
 586                 $info = $this->moduleInfos[$name];
 587                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 588                         return false;
 589                 }
 590                 return true;
 591         }
 592
 593         /**
 594          * Get the list of sources.
 595          *
 596          * @return array Like array( id => load.php url, .. )
 597          */
 598         public function getSources() {
 599                 return $this->sources;
 600         }
 601
 602         /**
 603          * Get the URL to the load.php endpoint for the given
 604          * ResourceLoader source
 605          *
 606          * @since 1.24
 607          * @param string $source
 608          * @throws MWException On an invalid $source name
 609          * @return string
 610          */
 611         public function getLoadScript( $source ) {
 612                 if ( !isset( $this->sources[$source] ) ) {
 613                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 614                 }
 615                 return $this->sources[$source];
 616         }
 617
 618         /**
 619          * @since 1.26
 620          * @param string $value
 621          * @return string Hash
 622          */
 623         public static function makeHash( $value ) {
 624                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 625                 // The first 8 chars of a base64 encoded digest represent the same binary as
 626                 // the first 12 chars of a hex encoded digest.
 627                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 628         }
 629
 630         /**
 631          * Helper method to get and combine versions of multiple modules.
 632          *
 633          * @since 1.26
 634          * @param ResourceLoaderContext $context
 635          * @param array $modules List of ResourceLoaderModule objects
 636          * @return string Hash
 637          */
 638         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 639                 if ( !$modules ) {
 640                         return '';
 641                 }
 642                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 643                 // http://php.net/functions.anonymous
 644                 $rl = $this;
 645                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 646                         return $rl->getModule( $module )->getVersionHash( $context );
 647                 }, $modules );
 648                 return self::makeHash( implode( $hashes ) );
 649         }
 650
 651         /**
 652          * Output a response to a load request, including the content-type header.
 653          *
 654          * @param ResourceLoaderContext $context Context in which a response should be formed
 655          */
 656         public function respond( ResourceLoaderContext $context ) {
 657                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 658                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 659                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 660                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 661                 // the whole thing in our own output buffer to be sure the active buffer
 662                 // doesn't use ob_gzhandler.
 663                 // See http://bugs.php.net/bug.php?id=36514
 664                 ob_start();
 665
 666                 // Find out which modules are missing and instantiate the others
 667                 $modules = array();
 668                 $missing = array();
 669                 foreach ( $context->getModules() as $name ) {
 670                         $module = $this->getModule( $name );
 671                         if ( $module ) {
 672                                 // Do not allow private modules to be loaded from the web.
 673                                 // This is a security issue, see bug 34907.
 674                                 if ( $module->getGroup() === 'private' ) {
 675                                         $this->logger->debug( "Request for private module '$name' denied" );
 676                                         $this->errors[] = "Cannot show private module \"$name\"";
 677                                         continue;
 678                                 }
 679                                 $modules[$name] = $module;
 680                         } else {
 681                                 $missing[] = $name;
 682                         }
 683                 }
 684
 685                 try {
 686                         // Preload for getCombinedVersion()
 687                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 688                 } catch ( Exception $e ) {
 689                         MWExceptionHandler::logException( $e );
 690                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 691                                 'exception' => $e
 692                         ) );
 693                         $this->errors[] = self::formatExceptionNoComment( $e );
 694                 }
 695
 696                 // Combine versions to propagate cache invalidation
 697                 $versionHash = '';
 698                 try {
 699                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 700                 } catch ( Exception $e ) {
 701                         MWExceptionHandler::logException( $e );
 702                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 703                                 'exception' => $e
 704                         ) );
 705                         $this->errors[] = self::formatExceptionNoComment( $e );
 706                 }
 707
 708                 // See RFC 2616 § 3.11 Entity Tags
 709                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 710                 $etag = 'W/"' . $versionHash . '"';
 711
 712                 // Try the client-side cache first
 713                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 714                         return; // output handled (buffers cleared)
 715                 }
 716
 717                 // Use file cache if enabled and available...
 718                 if ( $this->config->get( 'UseFileCache' ) ) {
 719                         $fileCache = ResourceFileCache::newFromContext( $context );
 720                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 721                                 return; // output handled
 722                         }
 723                 }
 724
 725                 // Generate a response
 726                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 727
 728                 // Capture any PHP warnings from the output buffer and append them to the
 729                 // error list if we're in debug mode.
 730                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 731                         $this->errors[] = $warnings;
 732                 }
 733
 734                 // Save response to file cache unless there are errors
 735                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 736                         // Cache single modules and images...and other requests if there are enough hits
 737                         if ( ResourceFileCache::useFileCache( $context ) ) {
 738                                 if ( $fileCache->isCacheWorthy() ) {
 739                                         $fileCache->saveText( $response );
 740                                 } else {
 741                                         $fileCache->incrMissesRecent( $context->getRequest() );
 742                                 }
 743                         }
 744                 }
 745
 746                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 747
 748                 // Remove the output buffer and output the response
 749                 ob_end_clean();
 750
 751                 if ( $context->getImageObj() && $this->errors ) {
 752                         // We can't show both the error messages and the response when it's an image.
 753                         $response = implode( "\n\n", $this->errors );
 754                 } elseif ( $this->errors ) {
 755                         $errorText = implode( "\n\n", $this->errors );
 756                         $errorResponse = self::makeComment( $errorText );
 757                         if ( $context->shouldIncludeScripts() ) {
 758                                 $errorResponse .= 'if (window.console && console.error) {'
 759                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 760                                         . "}\n";
 761                         }
 762
 763                         // Prepend error info to the response
 764                         $response = $errorResponse . $response;
 765                 }
 766
 767                 $this->errors = array();
 768                 echo $response;
 769
 770         }
 771
 772         /**
 773          * Send main response headers to the client.
 774          *
 775          * Deals with Content-Type, CORS (for stylesheets), and caching.
 776          *
 777          * @param ResourceLoaderContext $context
 778          * @param string $etag ETag header value
 779          * @param bool $errors Whether there are errors in the response
 780          * @return void
 781          */
 782         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 783                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 784                 // If a version wasn't specified we need a shorter expiry time for updates
 785                 // to propagate to clients quickly
 786                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 787                 if ( is_null( $context->getVersion() ) || $errors ) {
 788                         $maxage = $rlMaxage['unversioned']['client'];
 789                         $smaxage = $rlMaxage['unversioned']['server'];
 790                 // If a version was specified we can use a longer expiry time since changing
 791                 // version numbers causes cache misses
 792                 } else {
 793                         $maxage = $rlMaxage['versioned']['client'];
 794                         $smaxage = $rlMaxage['versioned']['server'];
 795                 }
 796                 if ( $context->getImageObj() ) {
 797                         // Output different headers if we're outputting textual errors.
 798                         if ( $errors ) {
 799                                 header( 'Content-Type: text/plain; charset=utf-8' );
 800                         } else {
 801                                 $context->getImageObj()->sendResponseHeaders( $context );
 802                         }
 803                 } elseif ( $context->getOnly() === 'styles' ) {
 804                         header( 'Content-Type: text/css; charset=utf-8' );
 805                         header( 'Access-Control-Allow-Origin: *' );
 806                 } else {
 807                         header( 'Content-Type: text/javascript; charset=utf-8' );
 808                 }
 809                 // See RFC 2616 § 14.19 ETag
 810                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 811                 header( 'ETag: ' . $etag );
 812                 if ( $context->getDebug() ) {
 813                         // Do not cache debug responses
 814                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 815                         header( 'Pragma: no-cache' );
 816                 } else {
 817                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 818                         $exp = min( $maxage, $smaxage );
 819                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 820                 }
 821
 822                 // Send the current time expressed as fractional seconds since epoch,
 823                 // with microsecond precision. This helps distinguish hits from misses
 824                 // in edge caches.
 825                 header( 'MediaWiki-Timestamp: ' . microtime( true ) );
 826         }
 827
 828         /**
 829          * Respond with HTTP 304 Not Modified if appropiate.
 830          *
 831          * If there's an If-None-Match header, respond with a 304 appropriately
 832          * and clear out the output buffer. If the client cache is too old then do nothing.
 833          *
 834          * @param ResourceLoaderContext $context
 835          * @param string $etag ETag header value
 836          * @return bool True if HTTP 304 was sent and output handled
 837          */
 838         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 839                 // See RFC 2616 § 14.26 If-None-Match
 840                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 841                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 842                 // Never send 304s in debug mode
 843                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 844                         // There's another bug in ob_gzhandler (see also the comment at
 845                         // the top of this function) that causes it to gzip even empty
 846                         // responses, meaning it's impossible to produce a truly empty
 847                         // response (because the gzip header is always there). This is
 848                         // a problem because 304 responses have to be completely empty
 849                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 850                         // See also http://bugs.php.net/bug.php?id=51579
 851                         // To work around this, we tear down all output buffering before
 852                         // sending the 304.
 853                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 854
 855                         HttpStatus::header( 304 );
 856
 857                         $this->sendResponseHeaders( $context, $etag, false );
 858                         return true;
 859                 }
 860                 return false;
 861         }
 862
 863         /**
 864          * Send out code for a response from file cache if possible.
 865          *
 866          * @param ResourceFileCache $fileCache Cache object for this request URL
 867          * @param ResourceLoaderContext $context Context in which to generate a response
 868          * @param string $etag ETag header value
 869          * @return bool If this found a cache file and handled the response
 870          */
 871         protected function tryRespondFromFileCache(
 872                 ResourceFileCache $fileCache,
 873                 ResourceLoaderContext $context,
 874                 $etag
 875         ) {
 876                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 877                 // Buffer output to catch warnings.
 878                 ob_start();
 879                 // Get the maximum age the cache can be
 880                 $maxage = is_null( $context->getVersion() )
 881                         ? $rlMaxage['unversioned']['server']
 882                         : $rlMaxage['versioned']['server'];
 883                 // Minimum timestamp the cache file must have
 884                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 885                 if ( !$good ) {
 886                         try { // RL always hits the DB on file cache miss...
 887                                 wfGetDB( DB_SLAVE );
 888                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 889                                 $good = $fileCache->isCacheGood(); // cache existence check
 890                         }
 891                 }
 892                 if ( $good ) {
 893                         $ts = $fileCache->cacheTimestamp();
 894                         // Send content type and cache headers
 895                         $this->sendResponseHeaders( $context, $etag, false );
 896                         $response = $fileCache->fetchText();
 897                         // Capture any PHP warnings from the output buffer and append them to the
 898                         // response in a comment if we're in debug mode.
 899                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 900                                 $response = self::makeComment( $warnings ) . $response;
 901                         }
 902                         // Remove the output buffer and output the response
 903                         ob_end_clean();
 904                         echo $response . "\n/* Cached {$ts} */";
 905                         return true; // cache hit
 906                 }
 907                 // Clear buffer
 908                 ob_end_clean();
 909
 910                 return false; // cache miss
 911         }
 912
 913         /**
 914          * Generate a CSS or JS comment block.
 915          *
 916          * Only use this for public data, not error message details.
 917          *
 918          * @param string $text
 919          * @return string
 920          */
 921         public static function makeComment( $text ) {
 922                 $encText = str_replace( '*/', '* /', $text );
 923                 return "/*\n$encText\n*/\n";
 924         }
 925
 926         /**
 927          * Handle exception display.
 928          *
 929          * @param Exception $e Exception to be shown to the user
 930          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 931          */
 932         public static function formatException( $e ) {
 933                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 934         }
 935
 936         /**
 937          * Handle exception display.
 938          *
 939          * @since 1.25
 940          * @param Exception $e Exception to be shown to the user
 941          * @return string Sanitized text that can be returned to the user
 942          */
 943         protected static function formatExceptionNoComment( $e ) {
 944                 global $wgShowExceptionDetails;
 945
 946                 if ( !$wgShowExceptionDetails ) {
 947                         return MWExceptionHandler::getPublicLogMessage( $e );
 948                 }
 949
 950                 return MWExceptionHandler::getLogMessage( $e );
 951         }
 952
 953         /**
 954          * Generate code for a response.
 955          *
 956          * @param ResourceLoaderContext $context Context in which to generate a response
 957          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 958          * @param string[] $missing List of requested module names that are unregistered (optional)
 959          * @return string Response data
 960          */
 961         public function makeModuleResponse( ResourceLoaderContext $context,
 962                 array $modules, array $missing = array()
 963         ) {
 964                 $out = '';
 965                 $states = array();
 966
 967                 if ( !count( $modules ) && !count( $missing ) ) {
 968                         return <<<MESSAGE
 969 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 970    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 971    no modules were requested. Max made me put this here. */
 972 MESSAGE;
 973                 }
 974
 975                 $image = $context->getImageObj();
 976                 if ( $image ) {
 977                         $data = $image->getImageData( $context );
 978                         if ( $data === false ) {
 979                                 $data = '';
 980                                 $this->errors[] = 'Image generation failed';
 981                         }
 982                         return $data;
 983                 }
 984
 985                 // Pre-fetch blobs
 986                 if ( $context->shouldIncludeMessages() ) {
 987                         try {
 988                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 989                         } catch ( Exception $e ) {
 990                                 MWExceptionHandler::logException( $e );
 991                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 992                                         'exception' => $e
 993                                 ) );
 994                                 $this->errors[] = self::formatExceptionNoComment( $e );
 995                         }
 996                 }
 997
 998                 foreach ( $missing as $name ) {
 999                         $states[$name] = 'missing';
1000                 }
1001
1002                 // Generate output
1003                 $isRaw = false;
1004
1005                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
1006
1007                 foreach ( $modules as $name => $module ) {
1008                         try {
1009                                 $content = $module->getModuleContent( $context );
1010                                 $strContent = '';
1011
1012                                 // Append output
1013                                 switch ( $context->getOnly() ) {
1014                                         case 'scripts':
1015                                                 $scripts = $content['scripts'];
1016                                                 if ( is_string( $scripts ) ) {
1017                                                         // Load scripts raw...
1018                                                         $strContent = $scripts;
1019                                                 } elseif ( is_array( $scripts ) ) {
1020                                                         // ...except when $scripts is an array of URLs
1021                                                         $strContent = self::makeLoaderImplementScript( $name, $scripts, array(), array(), array() );
1022                                                 }
1023                                                 break;
1024                                         case 'styles':
1025                                                 $styles = $content['styles'];
1026                                                 // We no longer seperate into media, they are all combined now with
1027                                                 // custom media type groups into @media .. {} sections as part of the css string.
1028                                                 // Module returns either an empty array or a numerical array with css strings.
1029                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1030                                                 break;
1031                                         default:
1032                                                 $strContent = self::makeLoaderImplementScript(
1033                                                         $name,
1034                                                         isset( $content['scripts'] ) ? $content['scripts'] : '',
1035                                                         isset( $content['styles'] ) ? $content['styles'] : array(),
1036                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : array(),
1037                                                         isset( $content['templates'] ) ? $content['templates'] : array()
1038                                                 );
1039                                                 break;
1040                                 }
1041
1042                                 if ( !$context->getDebug() ) {
1043                                         // Don't cache private modules. This is especially important in the case
1044                                         // of modules which change every time they are built, like the embedded
1045                                         // user.tokens module (bug T84960).
1046                                         $filterOptions = array( 'cache' => ( $module->getGroup() !== 'private' ) );
1047                                         $strContent = $this->filter( $filter, $strContent, $filterOptions );
1048                                 }
1049
1050                                 $out .= $strContent;
1051
1052                         } catch ( Exception $e ) {
1053                                 MWExceptionHandler::logException( $e );
1054                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1055                                         'exception' => $e
1056                                 ) );
1057                                 $this->errors[] = self::formatExceptionNoComment( $e );
1058
1059                                 // Respond to client with error-state instead of module implementation
1060                                 $states[$name] = 'error';
1061                                 unset( $modules[$name] );
1062                         }
1063                         $isRaw |= $module->isRaw();
1064                 }
1065
1066                 // Update module states
1067                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1068                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1069                                 // Set the state of modules loaded as only scripts to ready as
1070                                 // they don't have an mw.loader.implement wrapper that sets the state
1071                                 foreach ( $modules as $name => $module ) {
1072                                         $states[$name] = 'ready';
1073                                 }
1074                         }
1075
1076                         // Set the state of modules we didn't respond to with mw.loader.implement
1077                         if ( count( $states ) ) {
1078                                 $stateScript = self::makeLoaderStateScript( $states );
1079                                 if ( !$context->getDebug() ) {
1080                                         $stateScript = $this->filter( 'minify-js', $stateScript );
1081                                 }
1082                                 $out .= $stateScript;
1083                         }
1084                 } else {
1085                         if ( count( $states ) ) {
1086                                 $this->errors[] = 'Problematic modules: ' .
1087                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1088                         }
1089                 }
1090
1091                 return $out;
1092         }
1093
1094         /* Static Methods */
1095
1096         /**
1097          * Return JS code that calls mw.loader.implement with given module properties.
1098          *
1099          * @param string $name Module name
1100          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1101          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1102          *   to CSS files keyed by media type
1103          * @param mixed $messages List of messages associated with this module. May either be an
1104          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1105          *   the same data, wrapped in an XmlJsCode object.
1106          * @param array $templates Keys are name of templates and values are the source of
1107          *   the template.
1108          * @throws MWException
1109          * @return string
1110          */
1111         public static function makeLoaderImplementScript(
1112                 $name, $scripts, $styles, $messages, $templates
1113         ) {
1114                 if ( is_string( $scripts ) ) {
1115                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1116                         // Transportation as string instructs mw.loader.implement to use globalEval.
1117                         if ( $name === 'site' || $name === 'user' ) {
1118                                 // Minify manually because the general makeModuleResponse() minification won't be
1119                                 // effective here due to the script being a string instead of a function. (T107377)
1120                                 if ( !ResourceLoader::inDebugMode() ) {
1121                                         $scripts = self::applyFilter( 'minify-js', $scripts,
1122                                                 ConfigFactory::getDefaultInstance()->makeConfig( 'main' ) );
1123                                 }
1124                         } else {
1125                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1126                         }
1127                 } elseif ( !is_array( $scripts ) ) {
1128                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1129                 }
1130                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1131                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1132                 // of "{}". Force them to objects.
1133                 $module = array(
1134                         $name,
1135                         $scripts,
1136                         (object)$styles,
1137                         (object)$messages,
1138                         (object)$templates,
1139                 );
1140                 self::trimArray( $module );
1141
1142                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1143         }
1144
1145         /**
1146          * Returns JS code which, when called, will register a given list of messages.
1147          *
1148          * @param mixed $messages Either an associative array mapping message key to value, or a
1149          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1150          * @return string
1151          */
1152         public static function makeMessageSetScript( $messages ) {
1153                 return Xml::encodeJsCall(
1154                         'mw.messages.set',
1155                         array( (object)$messages ),
1156                         ResourceLoader::inDebugMode()
1157                 );
1158         }
1159
1160         /**
1161          * Combines an associative array mapping media type to CSS into a
1162          * single stylesheet with "@media" blocks.
1163          *
1164          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1165          * @return array
1166          */
1167         public static function makeCombinedStyles( array $stylePairs ) {
1168                 $out = array();
1169                 foreach ( $stylePairs as $media => $styles ) {
1170                         // ResourceLoaderFileModule::getStyle can return the styles
1171                         // as a string or an array of strings. This is to allow separation in
1172                         // the front-end.
1173                         $styles = (array)$styles;
1174                         foreach ( $styles as $style ) {
1175                                 $style = trim( $style );
1176                                 // Don't output an empty "@media print { }" block (bug 40498)
1177                                 if ( $style !== '' ) {
1178                                         // Transform the media type based on request params and config
1179                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1180                                         $media = OutputPage::transformCssMedia( $media );
1181
1182                                         if ( $media === '' || $media == 'all' ) {
1183                                                 $out[] = $style;
1184                                         } elseif ( is_string( $media ) ) {
1185                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1186                                         }
1187                                         // else: skip
1188                                 }
1189                         }
1190                 }
1191                 return $out;
1192         }
1193
1194         /**
1195          * Returns a JS call to mw.loader.state, which sets the state of a
1196          * module or modules to a given value. Has two calling conventions:
1197          *
1198          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1199          *         Set the state of a single module called $name to $state
1200          *
1201          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1202          *         Set the state of modules with the given names to the given states
1203          *
1204          * @param string $name
1205          * @param string $state
1206          * @return string
1207          */
1208         public static function makeLoaderStateScript( $name, $state = null ) {
1209                 if ( is_array( $name ) ) {
1210                         return Xml::encodeJsCall(
1211                                 'mw.loader.state',
1212                                 array( $name ),
1213                                 ResourceLoader::inDebugMode()
1214                         );
1215                 } else {
1216                         return Xml::encodeJsCall(
1217                                 'mw.loader.state',
1218                                 array( $name, $state ),
1219                                 ResourceLoader::inDebugMode()
1220                         );
1221                 }
1222         }
1223
1224         /**
1225          * Returns JS code which calls the script given by $script. The script will
1226          * be called with local variables name, version, dependencies and group,
1227          * which will have values corresponding to $name, $version, $dependencies
1228          * and $group as supplied.
1229          *
1230          * @param string $name Module name
1231          * @param string $version Module version hash
1232          * @param array $dependencies List of module names on which this module depends
1233          * @param string $group Group which the module is in.
1234          * @param string $source Source of the module, or 'local' if not foreign.
1235          * @param string $script JavaScript code
1236          * @return string
1237          */
1238         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1239                 $group, $source, $script
1240         ) {
1241                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1242                 return Xml::encodeJsCall(
1243                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1244                         array( $name, $version, $dependencies, $group, $source ),
1245                         ResourceLoader::inDebugMode()
1246                 );
1247         }
1248
1249         private static function isEmptyObject( stdClass $obj ) {
1250                 foreach ( $obj as $key => $value ) {
1251                         return false;
1252                 }
1253                 return true;
1254         }
1255
1256         /**
1257          * Remove empty values from the end of an array.
1258          *
1259          * Values considered empty:
1260          *
1261          * - null
1262          * - array()
1263          * - new XmlJsCode( '{}' )
1264          * - new stdClass() // (object) array()
1265          *
1266          * @param Array $array
1267          */
1268         private static function trimArray( Array &$array ) {
1269                 $i = count( $array );
1270                 while ( $i-- ) {
1271                         if ( $array[$i] === null
1272                                 || $array[$i] === array()
1273                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1274                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1275                         ) {
1276                                 unset( $array[$i] );
1277                         } else {
1278                                 break;
1279                         }
1280                 }
1281         }
1282
1283         /**
1284          * Returns JS code which calls mw.loader.register with the given
1285          * parameters. Has three calling conventions:
1286          *
1287          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1288          *        $dependencies, $group, $source, $skip
1289          *     ):
1290          *        Register a single module.
1291          *
1292          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1293          *        Register modules with the given names.
1294          *
1295          *   - ResourceLoader::makeLoaderRegisterScript( array(
1296          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1297          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1298          *        ...
1299          *     ) ):
1300          *        Registers modules with the given names and parameters.
1301          *
1302          * @param string $name Module name
1303          * @param string $version Module version hash
1304          * @param array $dependencies List of module names on which this module depends
1305          * @param string $group Group which the module is in
1306          * @param string $source Source of the module, or 'local' if not foreign
1307          * @param string $skip Script body of the skip function
1308          * @return string
1309          */
1310         public static function makeLoaderRegisterScript( $name, $version = null,
1311                 $dependencies = null, $group = null, $source = null, $skip = null
1312         ) {
1313                 if ( is_array( $name ) ) {
1314                         // Build module name index
1315                         $index = array();
1316                         foreach ( $name as $i => &$module ) {
1317                                 $index[$module[0]] = $i;
1318                         }
1319
1320                         // Transform dependency names into indexes when possible, they will be resolved by
1321                         // mw.loader.register on the other end
1322                         foreach ( $name as &$module ) {
1323                                 if ( isset( $module[2] ) ) {
1324                                         foreach ( $module[2] as &$dependency ) {
1325                                                 if ( isset( $index[$dependency] ) ) {
1326                                                         $dependency = $index[$dependency];
1327                                                 }
1328                                         }
1329                                 }
1330                         }
1331
1332                         array_walk( $name, array( 'self', 'trimArray' ) );
1333
1334                         return Xml::encodeJsCall(
1335                                 'mw.loader.register',
1336                                 array( $name ),
1337                                 ResourceLoader::inDebugMode()
1338                         );
1339                 } else {
1340                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1341                         self::trimArray( $registration );
1342                         return Xml::encodeJsCall(
1343                                 'mw.loader.register',
1344                                 $registration,
1345                                 ResourceLoader::inDebugMode()
1346                         );
1347                 }
1348         }
1349
1350         /**
1351          * Returns JS code which calls mw.loader.addSource() with the given
1352          * parameters. Has two calling conventions:
1353          *
1354          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1355          *       Register a single source
1356          *
1357          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1358          *       Register sources with the given IDs and properties.
1359          *
1360          * @param string $id Source ID
1361          * @param array $properties Source properties (see addSource())
1362          * @return string
1363          */
1364         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1365                 if ( is_array( $id ) ) {
1366                         return Xml::encodeJsCall(
1367                                 'mw.loader.addSource',
1368                                 array( $id ),
1369                                 ResourceLoader::inDebugMode()
1370                         );
1371                 } else {
1372                         return Xml::encodeJsCall(
1373                                 'mw.loader.addSource',
1374                                 array( $id, $properties ),
1375                                 ResourceLoader::inDebugMode()
1376                         );
1377                 }
1378         }
1379
1380         /**
1381          * Returns JS code which runs given JS code if the client-side framework is
1382          * present.
1383          *
1384          * @deprecated since 1.25; use makeInlineScript instead
1385          * @param string $script JavaScript code
1386          * @return string
1387          */
1388         public static function makeLoaderConditionalScript( $script ) {
1389                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1390                         trim( $script ) . "\n} );";
1391         }
1392
1393         /**
1394          * Construct an inline script tag with given JS code.
1395          *
1396          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1397          * only if the client has adequate support for MediaWiki JavaScript code.
1398          *
1399          * @param string $script JavaScript code
1400          * @return WrappedString HTML
1401          */
1402         public static function makeInlineScript( $script ) {
1403                 $js = self::makeLoaderConditionalScript( $script );
1404                 return new WrappedString(
1405                         Html::inlineScript( $js ),
1406                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1407                         "\n} );</script>"
1408                 );
1409         }
1410
1411         /**
1412          * Returns JS code which will set the MediaWiki configuration array to
1413          * the given value.
1414          *
1415          * @param array $configuration List of configuration values keyed by variable name
1416          * @return string
1417          */
1418         public static function makeConfigSetScript( array $configuration ) {
1419                 if ( ResourceLoader::inDebugMode() ) {
1420                         return Xml::encodeJsCall( 'mw.config.set', array( $configuration ), true );
1421                 }
1422
1423                 $config = RequestContext::getMain()->getConfig();
1424                 $js = Xml::encodeJsCall( 'mw.config.set', array( $configuration ), false );
1425                 return self::applyFilter( 'minify-js', $js, $config );
1426         }
1427
1428         /**
1429          * Convert an array of module names to a packed query string.
1430          *
1431          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1432          * becomes 'foo.bar,baz|bar.baz,quux'
1433          * @param array $modules List of module names (strings)
1434          * @return string Packed query string
1435          */
1436         public static function makePackedModulesString( $modules ) {
1437                 $groups = array(); // array( prefix => array( suffixes ) )
1438                 foreach ( $modules as $module ) {
1439                         $pos = strrpos( $module, '.' );
1440                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1441                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1442                         $groups[$prefix][] = $suffix;
1443                 }
1444
1445                 $arr = array();
1446                 foreach ( $groups as $prefix => $suffixes ) {
1447                         $p = $prefix === '' ? '' : $prefix . '.';
1448                         $arr[] = $p . implode( ',', $suffixes );
1449                 }
1450                 $str = implode( '|', $arr );
1451                 return $str;
1452         }
1453
1454         /**
1455          * Determine whether debug mode was requested
1456          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1457          * @return bool
1458          */
1459         public static function inDebugMode() {
1460                 if ( self::$debugMode === null ) {
1461                         global $wgRequest, $wgResourceLoaderDebug;
1462                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1463                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1464                         );
1465                 }
1466                 return self::$debugMode;
1467         }
1468
1469         /**
1470          * Reset static members used for caching.
1471          *
1472          * Global state and $wgRequest are evil, but we're using it right
1473          * now and sometimes we need to be able to force ResourceLoader to
1474          * re-evaluate the context because it has changed (e.g. in the test suite).
1475          */
1476         public static function clearCache() {
1477                 self::$debugMode = null;
1478         }
1479
1480         /**
1481          * Build a load.php URL
1482          *
1483          * @since 1.24
1484          * @param string $source Name of the ResourceLoader source
1485          * @param ResourceLoaderContext $context
1486          * @param array $extraQuery
1487          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1488          */
1489         public function createLoaderURL( $source, ResourceLoaderContext $context,
1490                 $extraQuery = array()
1491         ) {
1492                 $query = self::createLoaderQuery( $context, $extraQuery );
1493                 $script = $this->getLoadScript( $source );
1494
1495                 return wfAppendQuery( $script, $query );
1496         }
1497
1498         /**
1499          * Build a load.php URL
1500          * @deprecated since 1.24 Use createLoaderURL() instead
1501          * @param array $modules Array of module names (strings)
1502          * @param string $lang Language code
1503          * @param string $skin Skin name
1504          * @param string|null $user User name. If null, the &user= parameter is omitted
1505          * @param string|null $version Versioning timestamp
1506          * @param bool $debug Whether the request should be in debug mode
1507          * @param string|null $only &only= parameter
1508          * @param bool $printable Printable mode
1509          * @param bool $handheld Handheld mode
1510          * @param array $extraQuery Extra query parameters to add
1511          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1512          */
1513         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1514                 $version = null, $debug = false, $only = null, $printable = false,
1515                 $handheld = false, $extraQuery = array()
1516         ) {
1517                 global $wgLoadScript;
1518
1519                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1520                         $only, $printable, $handheld, $extraQuery
1521                 );
1522
1523                 return wfAppendQuery( $wgLoadScript, $query );
1524         }
1525
1526         /**
1527          * Helper for createLoaderURL()
1528          *
1529          * @since 1.24
1530          * @see makeLoaderQuery
1531          * @param ResourceLoaderContext $context
1532          * @param array $extraQuery
1533          * @return array
1534          */
1535         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1536                 return self::makeLoaderQuery(
1537                         $context->getModules(),
1538                         $context->getLanguage(),
1539                         $context->getSkin(),
1540                         $context->getUser(),
1541                         $context->getVersion(),
1542                         $context->getDebug(),
1543                         $context->getOnly(),
1544                         $context->getRequest()->getBool( 'printable' ),
1545                         $context->getRequest()->getBool( 'handheld' ),
1546                         $extraQuery
1547                 );
1548         }
1549
1550         /**
1551          * Build a query array (array representation of query string) for load.php. Helper
1552          * function for makeLoaderURL().
1553          *
1554          * @param array $modules
1555          * @param string $lang
1556          * @param string $skin
1557          * @param string $user
1558          * @param string $version
1559          * @param bool $debug
1560          * @param string $only
1561          * @param bool $printable
1562          * @param bool $handheld
1563          * @param array $extraQuery
1564          *
1565          * @return array
1566          */
1567         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1568                 $version = null, $debug = false, $only = null, $printable = false,
1569                 $handheld = false, $extraQuery = array()
1570         ) {
1571                 $query = array(
1572                         'modules' => self::makePackedModulesString( $modules ),
1573                         'lang' => $lang,
1574                         'skin' => $skin,
1575                         'debug' => $debug ? 'true' : 'false',
1576                 );
1577                 if ( $user !== null ) {
1578                         $query['user'] = $user;
1579                 }
1580                 if ( $version !== null ) {
1581                         $query['version'] = $version;
1582                 }
1583                 if ( $only !== null ) {
1584                         $query['only'] = $only;
1585                 }
1586                 if ( $printable ) {
1587                         $query['printable'] = 1;
1588                 }
1589                 if ( $handheld ) {
1590                         $query['handheld'] = 1;
1591                 }
1592                 $query += $extraQuery;
1593
1594                 // Make queries uniform in order
1595                 ksort( $query );
1596                 return $query;
1597         }
1598
1599         /**
1600          * Check a module name for validity.
1601          *
1602          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1603          * at most 255 bytes.
1604          *
1605          * @param string $moduleName Module name to check
1606          * @return bool Whether $moduleName is a valid module name
1607          */
1608         public static function isValidModuleName( $moduleName ) {
1609                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1610         }
1611
1612         /**
1613          * Returns LESS compiler set up for use with MediaWiki
1614          *
1615          * @since 1.22
1616          * @since 1.26 added $extraVars parameter
1617          * @param Config $config
1618          * @param array $extraVars Associative array of extra (i.e., other than the
1619          *   globally-configured ones) that should be used for compilation.
1620          * @throws MWException
1621          * @return Less_Parser
1622          */
1623         public static function getLessCompiler( Config $config, $extraVars = array() ) {
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( 'Less_Parser' ) ) {
1628                         throw new MWException( 'MediaWiki requires the less.php parser' );
1629                 }
1630
1631                 $parser = new Less_Parser;
1632                 $parser->ModifyVars( array_merge( self::getLessVars( $config ), $extraVars ) );
1633                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1634                 $parser->SetOption( 'relativeUrls', false );
1635                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1636
1637                 return $parser;
1638         }
1639
1640         /**
1641          * Get global LESS variables.
1642          *
1643          * @param Config $config
1644          * @since 1.22
1645          * @return array Map of variable names to string CSS values.
1646          */
1647         public static function getLessVars( Config $config ) {
1648                 if ( !self::$lessVars ) {
1649                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1650                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1651                         self::$lessVars = $lessVars;
1652                 }
1653                 return self::$lessVars;
1654         }
1655 }