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, FormatJson::decode( $row->md_deps, true ) );
 126                                 $modulesWithDeps[] = $row->md_module;
 127                         }
 128                 }
 129                 // Register the absence of a dependency row too
 130                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 131                         $module = $this->getModule( $name );
 132                         if ( $module ) {
 133                                 $this->getModule( $name )->setFileDependencies( $context, array() );
 134                         }
 135                 }
 136
 137                 // Get message blob mtimes. Only do this for modules with messages
 138                 $modulesWithMessages = array();
 139                 foreach ( $modules as $name ) {
 140                         $module = $this->getModule( $name );
 141                         if ( $module && count( $module->getMessages() ) ) {
 142                                 $modulesWithMessages[] = $name;
 143                         }
 144                 }
 145                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 146                 if ( count( $modulesWithMessages ) ) {
 147                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 148                                         'mr_resource' => $modulesWithMessages,
 149                                         'mr_lang' => $lang
 150                                 ), __METHOD__
 151                         );
 152                         foreach ( $res as $row ) {
 153                                 $module = $this->getModule( $row->mr_resource );
 154                                 if ( $module ) {
 155                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 156                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 157                                 }
 158                         }
 159                 }
 160                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 161                         $module = $this->getModule( $name );
 162                         if ( $module ) {
 163                                 $module->setMsgBlobMtime( $lang, 1 );
 164                         }
 165                 }
 166         }
 167
 168         /**
 169          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 170          *
 171          * Available filters are:
 172          *
 173          *    - minify-js \see JavaScriptMinifier::minify
 174          *    - minify-css \see CSSMin::minify
 175          *
 176          * If $data is empty, only contains whitespace or the filter was unknown,
 177          * $data is returned unmodified.
 178          *
 179          * @param string $filter Name of filter to run
 180          * @param string $data Text to filter, such as JavaScript or CSS text
 181          * @param array $options For back-compat, can also be the boolean value for "cacheReport". Keys:
 182          *  - (bool) cache: Whether to allow caching this data. Default: true.
 183          *  - (bool) cacheReport: Whether to include the "cache key" report comment. Default: false.
 184          * @return string Filtered data, or a comment containing an error message
 185          */
 186         public function filter( $filter, $data, $options = array() ) {
 187                 // Back-compat
 188                 if ( is_bool( $options ) ) {
 189                         $options = array( 'cacheReport' => $options );
 190                 }
 191                 // Defaults
 192                 $options += array( 'cache' => true, 'cacheReport' => false );
 193                 $stats = RequestContext::getMain()->getStats();
 194
 195                 // Don't filter empty content
 196                 if ( trim( $data ) === '' ) {
 197                         return $data;
 198                 }
 199
 200                 if ( !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 201                         $this->logger->warning( 'Invalid filter {filter}', array(
 202                                 'filter' => $filter
 203                         ) );
 204                         return $data;
 205                 }
 206
 207                 if ( !$options['cache'] ) {
 208                         $result = self::applyFilter( $filter, $data, $this->config );
 209                 } else {
 210                         $key = wfGlobalCacheKey(
 211                                 'resourceloader',
 212                                 'filter',
 213                                 $filter,
 214                                 self::$filterCacheVersion, md5( $data )
 215                         );
 216                         $cache = wfGetCache( wfIsHHVM() ? CACHE_ACCEL : CACHE_ANYTHING );
 217                         $cacheEntry = $cache->get( $key );
 218                         if ( is_string( $cacheEntry ) ) {
 219                                 $stats->increment( "resourceloader_cache.$filter.hit" );
 220                                 return $cacheEntry;
 221                         }
 222                         $result = '';
 223                         try {
 224                                 $statStart = microtime( true );
 225                                 $result = self::applyFilter( $filter, $data, $this->config );
 226                                 $statTiming = microtime( true ) - $statStart;
 227                                 $stats->increment( "resourceloader_cache.$filter.miss" );
 228                                 $stats->timing( "resourceloader_cache.$filter.timing", 1000 * $statTiming );
 229                                 if ( $options['cacheReport'] ) {
 230                                         $result .= "\n/* cache key: $key */";
 231                                 }
 232                                 // Set a TTL since HHVM's APC doesn't have any limitation or eviction logic.
 233                                 $cache->set( $key, $result, 24 * 3600 );
 234                         } catch ( Exception $e ) {
 235                                 MWExceptionHandler::logException( $e );
 236                                 $this->logger->warning( 'Minification failed: {exception}', array(
 237                                         'exception' => $e
 238                                 ) );
 239                                 $this->errors[] = self::formatExceptionNoComment( $e );
 240                         }
 241                 }
 242
 243                 return $result;
 244         }
 245
 246         private static function applyFilter( $filter, $data, Config $config ) {
 247                 switch ( $filter ) {
 248                         case 'minify-js':
 249                                 return JavaScriptMinifier::minify( $data );
 250                         case 'minify-css':
 251                                 return CSSMin::minify( $data );
 252                 }
 253
 254                 return $data;
 255         }
 256
 257         /* Methods */
 258
 259         /**
 260          * Register core modules and runs registration hooks.
 261          * @param Config|null $config
 262          */
 263         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 264                 global $IP;
 265
 266                 if ( !$logger ) {
 267                         $logger = new NullLogger();
 268                 }
 269                 $this->setLogger( $logger );
 270
 271                 if ( !$config ) {
 272                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 273                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 274                 }
 275                 $this->config = $config;
 276
 277                 // Add 'local' source first
 278                 $this->addSource( 'local', wfScript( 'load' ) );
 279
 280                 // Add other sources
 281                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 282
 283                 // Register core modules
 284                 $this->register( include "$IP/resources/Resources.php" );
 285                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 286                 // Register extension modules
 287                 $this->register( $config->get( 'ResourceModules' ) );
 288                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 289
 290                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 291                         $this->registerTestModules();
 292                 }
 293
 294                 $this->setMessageBlobStore( new MessageBlobStore() );
 295         }
 296
 297         /**
 298          * @return Config
 299          */
 300         public function getConfig() {
 301                 return $this->config;
 302         }
 303
 304         public function setLogger( LoggerInterface $logger ) {
 305                 $this->logger = $logger;
 306         }
 307
 308         /**
 309          * @since 1.26
 310          * @return MessageBlobStore
 311          */
 312         public function getMessageBlobStore() {
 313                 return $this->blobStore;
 314         }
 315
 316         /**
 317          * @since 1.25
 318          * @param MessageBlobStore $blobStore
 319          */
 320         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 321                 $this->blobStore = $blobStore;
 322         }
 323
 324         /**
 325          * Register a module with the ResourceLoader system.
 326          *
 327          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 328          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 329          *   this may also be a ResourceLoaderModule object. Optional when using
 330          *   multiple-registration calling style.
 331          * @throws MWException If a duplicate module registration is attempted
 332          * @throws MWException If a module name contains illegal characters (pipes or commas)
 333          * @throws MWException If something other than a ResourceLoaderModule is being registered
 334          * @return bool False if there were any errors, in which case one or more modules were
 335          *   not registered
 336          */
 337         public function register( $name, $info = null ) {
 338
 339                 // Allow multiple modules to be registered in one call
 340                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 341                 foreach ( $registrations as $name => $info ) {
 342                         // Disallow duplicate registrations
 343                         if ( isset( $this->moduleInfos[$name] ) ) {
 344                                 // A module has already been registered by this name
 345                                 throw new MWException(
 346                                         'ResourceLoader duplicate registration error. ' .
 347                                         'Another module has already been registered as ' . $name
 348                                 );
 349                         }
 350
 351                         // Check $name for validity
 352                         if ( !self::isValidModuleName( $name ) ) {
 353                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 354                                         . "see ResourceLoader::isValidModuleName()" );
 355                         }
 356
 357                         // Attach module
 358                         if ( $info instanceof ResourceLoaderModule ) {
 359                                 $this->moduleInfos[$name] = array( 'object' => $info );
 360                                 $info->setName( $name );
 361                                 $this->modules[$name] = $info;
 362                         } elseif ( is_array( $info ) ) {
 363                                 // New calling convention
 364                                 $this->moduleInfos[$name] = $info;
 365                         } else {
 366                                 throw new MWException(
 367                                         'ResourceLoader module info type error for module \'' . $name .
 368                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 369                                 );
 370                         }
 371
 372                         // Last-minute changes
 373
 374                         // Apply custom skin-defined styles to existing modules.
 375                         if ( $this->isFileModule( $name ) ) {
 376                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 377                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 378                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 379                                                 continue;
 380                                         }
 381
 382                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 383                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 384                                         if ( isset( $skinStyles[$name] ) ) {
 385                                                 $paths = (array)$skinStyles[$name];
 386                                                 $styleFiles = array();
 387                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 388                                                 $paths = (array)$skinStyles['+' . $name];
 389                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 390                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 391                                                         array();
 392                                         } else {
 393                                                 continue;
 394                                         }
 395
 396                                         // Add new file paths, remapping them to refer to our directories and not use settings
 397                                         // from the module we're modifying, which come from the base definition.
 398                                         list( $localBasePath, $remoteBasePath ) =
 399                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 400
 401                                         foreach ( $paths as $path ) {
 402                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 403                                         }
 404
 405                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 406                                 }
 407                         }
 408                 }
 409
 410         }
 411
 412         /**
 413          */
 414         public function registerTestModules() {
 415                 global $IP;
 416
 417                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 418                         throw new MWException( 'Attempt to register JavaScript test modules '
 419                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 420                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 421                 }
 422
 423                 // Get core test suites
 424                 $testModules = array();
 425                 $testModules['qunit'] = array();
 426                 // Get other test suites (e.g. from extensions)
 427                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 428
 429                 // Add the testrunner (which configures QUnit) to the dependencies.
 430                 // Since it must be ready before any of the test suites are executed.
 431                 foreach ( $testModules['qunit'] as &$module ) {
 432                         // Make sure all test modules are top-loading so that when QUnit starts
 433                         // on document-ready, it will run once and finish. If some tests arrive
 434                         // later (possibly after QUnit has already finished) they will be ignored.
 435                         $module['position'] = 'top';
 436                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 437                 }
 438
 439                 $testModules['qunit'] =
 440                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 441
 442                 foreach ( $testModules as $id => $names ) {
 443                         // Register test modules
 444                         $this->register( $testModules[$id] );
 445
 446                         // Keep track of their names so that they can be loaded together
 447                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 448                 }
 449
 450         }
 451
 452         /**
 453          * Add a foreign source of modules.
 454          *
 455          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 456          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 457          *  backwards-compatibility.
 458          * @throws MWException
 459          */
 460         public function addSource( $id, $loadUrl = null ) {
 461                 // Allow multiple sources to be registered in one call
 462                 if ( is_array( $id ) ) {
 463                         foreach ( $id as $key => $value ) {
 464                                 $this->addSource( $key, $value );
 465                         }
 466                         return;
 467                 }
 468
 469                 // Disallow duplicates
 470                 if ( isset( $this->sources[$id] ) ) {
 471                         throw new MWException(
 472                                 'ResourceLoader duplicate source addition error. ' .
 473                                 'Another source has already been registered as ' . $id
 474                         );
 475                 }
 476
 477                 // Pre 1.24 backwards-compatibility
 478                 if ( is_array( $loadUrl ) ) {
 479                         if ( !isset( $loadUrl['loadScript'] ) ) {
 480                                 throw new MWException(
 481                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 482                                 );
 483                         }
 484
 485                         $loadUrl = $loadUrl['loadScript'];
 486                 }
 487
 488                 $this->sources[$id] = $loadUrl;
 489         }
 490
 491         /**
 492          * Get a list of module names.
 493          *
 494          * @return array List of module names
 495          */
 496         public function getModuleNames() {
 497                 return array_keys( $this->moduleInfos );
 498         }
 499
 500         /**
 501          * Get a list of test module names for one (or all) frameworks.
 502          *
 503          * If the given framework id is unknkown, or if the in-object variable is not an array,
 504          * then it will return an empty array.
 505          *
 506          * @param string $framework Get only the test module names for one
 507          *   particular framework (optional)
 508          * @return array
 509          */
 510         public function getTestModuleNames( $framework = 'all' ) {
 511                 /** @todo api siteinfo prop testmodulenames modulenames */
 512                 if ( $framework == 'all' ) {
 513                         return $this->testModuleNames;
 514                 } elseif ( isset( $this->testModuleNames[$framework] )
 515                         && is_array( $this->testModuleNames[$framework] )
 516                 ) {
 517                         return $this->testModuleNames[$framework];
 518                 } else {
 519                         return array();
 520                 }
 521         }
 522
 523         /**
 524          * Check whether a ResourceLoader module is registered
 525          *
 526          * @since 1.25
 527          * @param string $name
 528          * @return bool
 529          */
 530         public function isModuleRegistered( $name ) {
 531                 return isset( $this->moduleInfos[$name] );
 532         }
 533
 534         /**
 535          * Get the ResourceLoaderModule object for a given module name.
 536          *
 537          * If an array of module parameters exists but a ResourceLoaderModule object has not
 538          * yet been instantiated, this method will instantiate and cache that object such that
 539          * subsequent calls simply return the same object.
 540          *
 541          * @param string $name Module name
 542          * @return ResourceLoaderModule|null If module has been registered, return a
 543          *  ResourceLoaderModule instance. Otherwise, return null.
 544          */
 545         public function getModule( $name ) {
 546                 if ( !isset( $this->modules[$name] ) ) {
 547                         if ( !isset( $this->moduleInfos[$name] ) ) {
 548                                 // No such module
 549                                 return null;
 550                         }
 551                         // Construct the requested object
 552                         $info = $this->moduleInfos[$name];
 553                         /** @var ResourceLoaderModule $object */
 554                         if ( isset( $info['object'] ) ) {
 555                                 // Object given in info array
 556                                 $object = $info['object'];
 557                         } else {
 558                                 if ( !isset( $info['class'] ) ) {
 559                                         $class = 'ResourceLoaderFileModule';
 560                                 } else {
 561                                         $class = $info['class'];
 562                                 }
 563                                 /** @var ResourceLoaderModule $object */
 564                                 $object = new $class( $info );
 565                                 $object->setConfig( $this->getConfig() );
 566                         }
 567                         $object->setName( $name );
 568                         $this->modules[$name] = $object;
 569                 }
 570
 571                 return $this->modules[$name];
 572         }
 573
 574         /**
 575          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 576          *
 577          * @param string $name Module name
 578          * @return bool
 579          */
 580         protected function isFileModule( $name ) {
 581                 if ( !isset( $this->moduleInfos[$name] ) ) {
 582                         return false;
 583                 }
 584                 $info = $this->moduleInfos[$name];
 585                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 586                         return false;
 587                 }
 588                 return true;
 589         }
 590
 591         /**
 592          * Get the list of sources.
 593          *
 594          * @return array Like array( id => load.php url, .. )
 595          */
 596         public function getSources() {
 597                 return $this->sources;
 598         }
 599
 600         /**
 601          * Get the URL to the load.php endpoint for the given
 602          * ResourceLoader source
 603          *
 604          * @since 1.24
 605          * @param string $source
 606          * @throws MWException On an invalid $source name
 607          * @return string
 608          */
 609         public function getLoadScript( $source ) {
 610                 if ( !isset( $this->sources[$source] ) ) {
 611                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 612                 }
 613                 return $this->sources[$source];
 614         }
 615
 616         /**
 617          * @since 1.26
 618          * @param string $value
 619          * @return string Hash
 620          */
 621         public static function makeHash( $value ) {
 622                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 623                 // The first 8 chars of a base64 encoded digest represent the same binary as
 624                 // the first 12 chars of a hex encoded digest.
 625                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 626         }
 627
 628         /**
 629          * Helper method to get and combine versions of multiple modules.
 630          *
 631          * @since 1.26
 632          * @param ResourceLoaderContext $context
 633          * @param array $modules List of ResourceLoaderModule objects
 634          * @return string Hash
 635          */
 636         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 637                 if ( !$modules ) {
 638                         return '';
 639                 }
 640                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 641                 // http://php.net/functions.anonymous
 642                 $rl = $this;
 643                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 644                         return $rl->getModule( $module )->getVersionHash( $context );
 645                 }, $modules );
 646                 return self::makeHash( implode( $hashes ) );
 647         }
 648
 649         /**
 650          * Output a response to a load request, including the content-type header.
 651          *
 652          * @param ResourceLoaderContext $context Context in which a response should be formed
 653          */
 654         public function respond( ResourceLoaderContext $context ) {
 655                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 656                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 657                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 658                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 659                 // the whole thing in our own output buffer to be sure the active buffer
 660                 // doesn't use ob_gzhandler.
 661                 // See http://bugs.php.net/bug.php?id=36514
 662                 ob_start();
 663
 664                 // Find out which modules are missing and instantiate the others
 665                 $modules = array();
 666                 $missing = array();
 667                 foreach ( $context->getModules() as $name ) {
 668                         $module = $this->getModule( $name );
 669                         if ( $module ) {
 670                                 // Do not allow private modules to be loaded from the web.
 671                                 // This is a security issue, see bug 34907.
 672                                 if ( $module->getGroup() === 'private' ) {
 673                                         $this->logger->debug( "Request for private module '$name' denied" );
 674                                         $this->errors[] = "Cannot show private module \"$name\"";
 675                                         continue;
 676                                 }
 677                                 $modules[$name] = $module;
 678                         } else {
 679                                 $missing[] = $name;
 680                         }
 681                 }
 682
 683                 try {
 684                         // Preload for getCombinedVersion()
 685                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 686                 } catch ( Exception $e ) {
 687                         MWExceptionHandler::logException( $e );
 688                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 689                                 'exception' => $e
 690                         ) );
 691                         $this->errors[] = self::formatExceptionNoComment( $e );
 692                 }
 693
 694                 // Combine versions to propagate cache invalidation
 695                 $versionHash = '';
 696                 try {
 697                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 698                 } catch ( Exception $e ) {
 699                         MWExceptionHandler::logException( $e );
 700                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 701                                 'exception' => $e
 702                         ) );
 703                         $this->errors[] = self::formatExceptionNoComment( $e );
 704                 }
 705
 706                 // See RFC 2616 § 3.11 Entity Tags
 707                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 708                 $etag = 'W/"' . $versionHash . '"';
 709
 710                 // Try the client-side cache first
 711                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 712                         return; // output handled (buffers cleared)
 713                 }
 714
 715                 // Use file cache if enabled and available...
 716                 if ( $this->config->get( 'UseFileCache' ) ) {
 717                         $fileCache = ResourceFileCache::newFromContext( $context );
 718                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 719                                 return; // output handled
 720                         }
 721                 }
 722
 723                 // Generate a response
 724                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 725
 726                 // Capture any PHP warnings from the output buffer and append them to the
 727                 // error list if we're in debug mode.
 728                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 729                         $this->errors[] = $warnings;
 730                 }
 731
 732                 // Save response to file cache unless there are errors
 733                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 734                         // Cache single modules and images...and other requests if there are enough hits
 735                         if ( ResourceFileCache::useFileCache( $context ) ) {
 736                                 if ( $fileCache->isCacheWorthy() ) {
 737                                         $fileCache->saveText( $response );
 738                                 } else {
 739                                         $fileCache->incrMissesRecent( $context->getRequest() );
 740                                 }
 741                         }
 742                 }
 743
 744                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 745
 746                 // Remove the output buffer and output the response
 747                 ob_end_clean();
 748
 749                 if ( $context->getImageObj() && $this->errors ) {
 750                         // We can't show both the error messages and the response when it's an image.
 751                         $response = implode( "\n\n", $this->errors );
 752                 } elseif ( $this->errors ) {
 753                         $errorText = implode( "\n\n", $this->errors );
 754                         $errorResponse = self::makeComment( $errorText );
 755                         if ( $context->shouldIncludeScripts() ) {
 756                                 $errorResponse .= 'if (window.console && console.error) {'
 757                                         . Xml::encodeJsCall( 'console.error', array( $errorText ) )
 758                                         . "}\n";
 759                         }
 760
 761                         // Prepend error info to the response
 762                         $response = $errorResponse . $response;
 763                 }
 764
 765                 $this->errors = array();
 766                 echo $response;
 767
 768         }
 769
 770         /**
 771          * Send main response headers to the client.
 772          *
 773          * Deals with Content-Type, CORS (for stylesheets), and caching.
 774          *
 775          * @param ResourceLoaderContext $context
 776          * @param string $etag ETag header value
 777          * @param bool $errors Whether there are errors in the response
 778          * @return void
 779          */
 780         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 781                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 782                 // If a version wasn't specified we need a shorter expiry time for updates
 783                 // to propagate to clients quickly
 784                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 785                 if ( is_null( $context->getVersion() ) || $errors ) {
 786                         $maxage = $rlMaxage['unversioned']['client'];
 787                         $smaxage = $rlMaxage['unversioned']['server'];
 788                 // If a version was specified we can use a longer expiry time since changing
 789                 // version numbers causes cache misses
 790                 } else {
 791                         $maxage = $rlMaxage['versioned']['client'];
 792                         $smaxage = $rlMaxage['versioned']['server'];
 793                 }
 794                 if ( $context->getImageObj() ) {
 795                         // Output different headers if we're outputting textual errors.
 796                         if ( $errors ) {
 797                                 header( 'Content-Type: text/plain; charset=utf-8' );
 798                         } else {
 799                                 $context->getImageObj()->sendResponseHeaders( $context );
 800                         }
 801                 } elseif ( $context->getOnly() === 'styles' ) {
 802                         header( 'Content-Type: text/css; charset=utf-8' );
 803                         header( 'Access-Control-Allow-Origin: *' );
 804                 } else {
 805                         header( 'Content-Type: text/javascript; charset=utf-8' );
 806                 }
 807                 // See RFC 2616 § 14.19 ETag
 808                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 809                 header( 'ETag: ' . $etag );
 810                 if ( $context->getDebug() ) {
 811                         // Do not cache debug responses
 812                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 813                         header( 'Pragma: no-cache' );
 814                 } else {
 815                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 816                         $exp = min( $maxage, $smaxage );
 817                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 818                 }
 819
 820                 // Send the current time expressed as fractional seconds since epoch,
 821                 // with microsecond precision. This helps distinguish hits from misses
 822                 // in edge caches.
 823                 header( 'MediaWiki-Timestamp: ' . microtime( true ) );
 824         }
 825
 826         /**
 827          * Respond with HTTP 304 Not Modified if appropiate.
 828          *
 829          * If there's an If-None-Match header, respond with a 304 appropriately
 830          * and clear out the output buffer. If the client cache is too old then do nothing.
 831          *
 832          * @param ResourceLoaderContext $context
 833          * @param string $etag ETag header value
 834          * @return bool True if HTTP 304 was sent and output handled
 835          */
 836         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 837                 // See RFC 2616 § 14.26 If-None-Match
 838                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 839                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 840                 // Never send 304s in debug mode
 841                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 842                         // There's another bug in ob_gzhandler (see also the comment at
 843                         // the top of this function) that causes it to gzip even empty
 844                         // responses, meaning it's impossible to produce a truly empty
 845                         // response (because the gzip header is always there). This is
 846                         // a problem because 304 responses have to be completely empty
 847                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 848                         // See also http://bugs.php.net/bug.php?id=51579
 849                         // To work around this, we tear down all output buffering before
 850                         // sending the 304.
 851                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 852
 853                         HttpStatus::header( 304 );
 854
 855                         $this->sendResponseHeaders( $context, $etag, false );
 856                         return true;
 857                 }
 858                 return false;
 859         }
 860
 861         /**
 862          * Send out code for a response from file cache if possible.
 863          *
 864          * @param ResourceFileCache $fileCache Cache object for this request URL
 865          * @param ResourceLoaderContext $context Context in which to generate a response
 866          * @param string $etag ETag header value
 867          * @return bool If this found a cache file and handled the response
 868          */
 869         protected function tryRespondFromFileCache(
 870                 ResourceFileCache $fileCache,
 871                 ResourceLoaderContext $context,
 872                 $etag
 873         ) {
 874                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 875                 // Buffer output to catch warnings.
 876                 ob_start();
 877                 // Get the maximum age the cache can be
 878                 $maxage = is_null( $context->getVersion() )
 879                         ? $rlMaxage['unversioned']['server']
 880                         : $rlMaxage['versioned']['server'];
 881                 // Minimum timestamp the cache file must have
 882                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 883                 if ( !$good ) {
 884                         try { // RL always hits the DB on file cache miss...
 885                                 wfGetDB( DB_SLAVE );
 886                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 887                                 $good = $fileCache->isCacheGood(); // cache existence check
 888                         }
 889                 }
 890                 if ( $good ) {
 891                         $ts = $fileCache->cacheTimestamp();
 892                         // Send content type and cache headers
 893                         $this->sendResponseHeaders( $context, $etag, false );
 894                         $response = $fileCache->fetchText();
 895                         // Capture any PHP warnings from the output buffer and append them to the
 896                         // response in a comment if we're in debug mode.
 897                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 898                                 $response = self::makeComment( $warnings ) . $response;
 899                         }
 900                         // Remove the output buffer and output the response
 901                         ob_end_clean();
 902                         echo $response . "\n/* Cached {$ts} */";
 903                         return true; // cache hit
 904                 }
 905                 // Clear buffer
 906                 ob_end_clean();
 907
 908                 return false; // cache miss
 909         }
 910
 911         /**
 912          * Generate a CSS or JS comment block.
 913          *
 914          * Only use this for public data, not error message details.
 915          *
 916          * @param string $text
 917          * @return string
 918          */
 919         public static function makeComment( $text ) {
 920                 $encText = str_replace( '*/', '* /', $text );
 921                 return "/*\n$encText\n*/\n";
 922         }
 923
 924         /**
 925          * Handle exception display.
 926          *
 927          * @param Exception $e Exception to be shown to the user
 928          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 929          */
 930         public static function formatException( $e ) {
 931                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 932         }
 933
 934         /**
 935          * Handle exception display.
 936          *
 937          * @since 1.25
 938          * @param Exception $e Exception to be shown to the user
 939          * @return string Sanitized text that can be returned to the user
 940          */
 941         protected static function formatExceptionNoComment( $e ) {
 942                 global $wgShowExceptionDetails;
 943
 944                 if ( !$wgShowExceptionDetails ) {
 945                         return MWExceptionHandler::getPublicLogMessage( $e );
 946                 }
 947
 948                 return MWExceptionHandler::getLogMessage( $e );
 949         }
 950
 951         /**
 952          * Generate code for a response.
 953          *
 954          * @param ResourceLoaderContext $context Context in which to generate a response
 955          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 956          * @param string[] $missing List of requested module names that are unregistered (optional)
 957          * @return string Response data
 958          */
 959         public function makeModuleResponse( ResourceLoaderContext $context,
 960                 array $modules, array $missing = array()
 961         ) {
 962                 $out = '';
 963                 $states = array();
 964
 965                 if ( !count( $modules ) && !count( $missing ) ) {
 966                         return <<<MESSAGE
 967 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 968    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 969    no modules were requested. Max made me put this here. */
 970 MESSAGE;
 971                 }
 972
 973                 $image = $context->getImageObj();
 974                 if ( $image ) {
 975                         $data = $image->getImageData( $context );
 976                         if ( $data === false ) {
 977                                 $data = '';
 978                                 $this->errors[] = 'Image generation failed';
 979                         }
 980                         return $data;
 981                 }
 982
 983                 // Pre-fetch blobs
 984                 if ( $context->shouldIncludeMessages() ) {
 985                         try {
 986                                 $this->blobStore->get( $this, $modules, $context->getLanguage() );
 987                         } catch ( Exception $e ) {
 988                                 MWExceptionHandler::logException( $e );
 989                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 990                                         'exception' => $e
 991                                 ) );
 992                                 $this->errors[] = self::formatExceptionNoComment( $e );
 993                         }
 994                 }
 995
 996                 foreach ( $missing as $name ) {
 997                         $states[$name] = 'missing';
 998                 }
 999
1000                 // Generate output
1001                 $isRaw = false;
1002
1003                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
1004
1005                 foreach ( $modules as $name => $module ) {
1006                         try {
1007                                 $content = $module->getModuleContent( $context );
1008                                 $strContent = '';
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                                                         $strContent = $scripts;
1017                                                 } elseif ( is_array( $scripts ) ) {
1018                                                         // ...except when $scripts is an array of URLs
1019                                                         $strContent = 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                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1028                                                 break;
1029                                         default:
1030                                                 $strContent = 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'] ) ? $content['templates'] : array()
1036                                                 );
1037                                                 break;
1038                                 }
1039
1040                                 if ( !$context->getDebug() ) {
1041                                         // Don't cache private modules. This is especially important in the case
1042                                         // of modules which change every time they are built, like the embedded
1043                                         // user.tokens module (bug T84960).
1044                                         $filterOptions = array( 'cache' => ( $module->getGroup() !== 'private' ) );
1045                                         $strContent = $this->filter( $filter, $strContent, $filterOptions );
1046                                 }
1047
1048                                 $out .= $strContent;
1049
1050                         } catch ( Exception $e ) {
1051                                 MWExceptionHandler::logException( $e );
1052                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1053                                         'exception' => $e
1054                                 ) );
1055                                 $this->errors[] = self::formatExceptionNoComment( $e );
1056
1057                                 // Respond to client with error-state instead of module implementation
1058                                 $states[$name] = 'error';
1059                                 unset( $modules[$name] );
1060                         }
1061                         $isRaw |= $module->isRaw();
1062                 }
1063
1064                 // Update module states
1065                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1066                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1067                                 // Set the state of modules loaded as only scripts to ready as
1068                                 // they don't have an mw.loader.implement wrapper that sets the state
1069                                 foreach ( $modules as $name => $module ) {
1070                                         $states[$name] = 'ready';
1071                                 }
1072                         }
1073
1074                         // Set the state of modules we didn't respond to with mw.loader.implement
1075                         if ( count( $states ) ) {
1076                                 $stateScript = self::makeLoaderStateScript( $states );
1077                                 if ( !$context->getDebug() ) {
1078                                         $stateScript = $this->filter( 'minify-js', $stateScript );
1079                                 }
1080                                 $out .= $stateScript;
1081                         }
1082                 } else {
1083                         if ( count( $states ) ) {
1084                                 $this->errors[] = 'Problematic modules: ' .
1085                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1086                         }
1087                 }
1088
1089                 return $out;
1090         }
1091
1092         /* Static Methods */
1093
1094         /**
1095          * Return JS code that calls mw.loader.implement with given module properties.
1096          *
1097          * @param string $name Module name
1098          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1099          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1100          *   to CSS files keyed by media type
1101          * @param mixed $messages List of messages associated with this module. May either be an
1102          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1103          *   the same data, wrapped in an XmlJsCode object.
1104          * @param array $templates Keys are name of templates and values are the source of
1105          *   the template.
1106          * @throws MWException
1107          * @return string
1108          */
1109         public static function makeLoaderImplementScript(
1110                 $name, $scripts, $styles, $messages, $templates
1111         ) {
1112                 if ( is_string( $scripts ) ) {
1113                         // Site and user module are a legacy scripts that run in the global scope (no closure).
1114                         // Transportation as string instructs mw.loader.implement to use globalEval.
1115                         if ( $name === 'site' || $name === 'user' ) {
1116                                 // Minify manually because the general makeModuleResponse() minification won't be
1117                                 // effective here due to the script being a string instead of a function. (T107377)
1118                                 if ( !ResourceLoader::inDebugMode() ) {
1119                                         $scripts = self::applyFilter( 'minify-js', $scripts,
1120                                                 ConfigFactory::getDefaultInstance()->makeConfig( 'main' ) );
1121                                 }
1122                         } else {
1123                                 $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1124                         }
1125                 } elseif ( !is_array( $scripts ) ) {
1126                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1127                 }
1128                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1129                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1130                 // of "{}". Force them to objects.
1131                 $module = array(
1132                         $name,
1133                         $scripts,
1134                         (object)$styles,
1135                         (object)$messages,
1136                         (object)$templates,
1137                 );
1138                 self::trimArray( $module );
1139
1140                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1141         }
1142
1143         /**
1144          * Returns JS code which, when called, will register a given list of messages.
1145          *
1146          * @param mixed $messages Either an associative array mapping message key to value, or a
1147          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1148          * @return string
1149          */
1150         public static function makeMessageSetScript( $messages ) {
1151                 return Xml::encodeJsCall(
1152                         'mw.messages.set',
1153                         array( (object)$messages ),
1154                         ResourceLoader::inDebugMode()
1155                 );
1156         }
1157
1158         /**
1159          * Combines an associative array mapping media type to CSS into a
1160          * single stylesheet with "@media" blocks.
1161          *
1162          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1163          * @return array
1164          */
1165         public static function makeCombinedStyles( array $stylePairs ) {
1166                 $out = array();
1167                 foreach ( $stylePairs as $media => $styles ) {
1168                         // ResourceLoaderFileModule::getStyle can return the styles
1169                         // as a string or an array of strings. This is to allow separation in
1170                         // the front-end.
1171                         $styles = (array)$styles;
1172                         foreach ( $styles as $style ) {
1173                                 $style = trim( $style );
1174                                 // Don't output an empty "@media print { }" block (bug 40498)
1175                                 if ( $style !== '' ) {
1176                                         // Transform the media type based on request params and config
1177                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1178                                         $media = OutputPage::transformCssMedia( $media );
1179
1180                                         if ( $media === '' || $media == 'all' ) {
1181                                                 $out[] = $style;
1182                                         } elseif ( is_string( $media ) ) {
1183                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1184                                         }
1185                                         // else: skip
1186                                 }
1187                         }
1188                 }
1189                 return $out;
1190         }
1191
1192         /**
1193          * Returns a JS call to mw.loader.state, which sets the state of a
1194          * module or modules to a given value. Has two calling conventions:
1195          *
1196          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1197          *         Set the state of a single module called $name to $state
1198          *
1199          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1200          *         Set the state of modules with the given names to the given states
1201          *
1202          * @param string $name
1203          * @param string $state
1204          * @return string
1205          */
1206         public static function makeLoaderStateScript( $name, $state = null ) {
1207                 if ( is_array( $name ) ) {
1208                         return Xml::encodeJsCall(
1209                                 'mw.loader.state',
1210                                 array( $name ),
1211                                 ResourceLoader::inDebugMode()
1212                         );
1213                 } else {
1214                         return Xml::encodeJsCall(
1215                                 'mw.loader.state',
1216                                 array( $name, $state ),
1217                                 ResourceLoader::inDebugMode()
1218                         );
1219                 }
1220         }
1221
1222         /**
1223          * Returns JS code which calls the script given by $script. The script will
1224          * be called with local variables name, version, dependencies and group,
1225          * which will have values corresponding to $name, $version, $dependencies
1226          * and $group as supplied.
1227          *
1228          * @param string $name Module name
1229          * @param string $version Module version hash
1230          * @param array $dependencies List of module names on which this module depends
1231          * @param string $group Group which the module is in.
1232          * @param string $source Source of the module, or 'local' if not foreign.
1233          * @param string $script JavaScript code
1234          * @return string
1235          */
1236         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1237                 $group, $source, $script
1238         ) {
1239                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1240                 return Xml::encodeJsCall(
1241                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1242                         array( $name, $version, $dependencies, $group, $source ),
1243                         ResourceLoader::inDebugMode()
1244                 );
1245         }
1246
1247         private static function isEmptyObject( stdClass $obj ) {
1248                 foreach ( $obj as $key => $value ) {
1249                         return false;
1250                 }
1251                 return true;
1252         }
1253
1254         /**
1255          * Remove empty values from the end of an array.
1256          *
1257          * Values considered empty:
1258          *
1259          * - null
1260          * - array()
1261          * - new XmlJsCode( '{}' )
1262          * - new stdClass() // (object) array()
1263          *
1264          * @param Array $array
1265          */
1266         private static function trimArray( Array &$array ) {
1267                 $i = count( $array );
1268                 while ( $i-- ) {
1269                         if ( $array[$i] === null
1270                                 || $array[$i] === array()
1271                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1272                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1273                         ) {
1274                                 unset( $array[$i] );
1275                         } else {
1276                                 break;
1277                         }
1278                 }
1279         }
1280
1281         /**
1282          * Returns JS code which calls mw.loader.register with the given
1283          * parameters. Has three calling conventions:
1284          *
1285          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1286          *        $dependencies, $group, $source, $skip
1287          *     ):
1288          *        Register a single module.
1289          *
1290          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1291          *        Register modules with the given names.
1292          *
1293          *   - ResourceLoader::makeLoaderRegisterScript( array(
1294          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1295          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1296          *        ...
1297          *     ) ):
1298          *        Registers modules with the given names and parameters.
1299          *
1300          * @param string $name Module name
1301          * @param string $version Module version hash
1302          * @param array $dependencies List of module names on which this module depends
1303          * @param string $group Group which the module is in
1304          * @param string $source Source of the module, or 'local' if not foreign
1305          * @param string $skip Script body of the skip function
1306          * @return string
1307          */
1308         public static function makeLoaderRegisterScript( $name, $version = null,
1309                 $dependencies = null, $group = null, $source = null, $skip = null
1310         ) {
1311                 if ( is_array( $name ) ) {
1312                         // Build module name index
1313                         $index = array();
1314                         foreach ( $name as $i => &$module ) {
1315                                 $index[$module[0]] = $i;
1316                         }
1317
1318                         // Transform dependency names into indexes when possible, they will be resolved by
1319                         // mw.loader.register on the other end
1320                         foreach ( $name as &$module ) {
1321                                 if ( isset( $module[2] ) ) {
1322                                         foreach ( $module[2] as &$dependency ) {
1323                                                 if ( isset( $index[$dependency] ) ) {
1324                                                         $dependency = $index[$dependency];
1325                                                 }
1326                                         }
1327                                 }
1328                         }
1329
1330                         array_walk( $name, array( 'self', 'trimArray' ) );
1331
1332                         return Xml::encodeJsCall(
1333                                 'mw.loader.register',
1334                                 array( $name ),
1335                                 ResourceLoader::inDebugMode()
1336                         );
1337                 } else {
1338                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1339                         self::trimArray( $registration );
1340                         return Xml::encodeJsCall(
1341                                 'mw.loader.register',
1342                                 $registration,
1343                                 ResourceLoader::inDebugMode()
1344                         );
1345                 }
1346         }
1347
1348         /**
1349          * Returns JS code which calls mw.loader.addSource() with the given
1350          * parameters. Has two calling conventions:
1351          *
1352          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1353          *       Register a single source
1354          *
1355          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1356          *       Register sources with the given IDs and properties.
1357          *
1358          * @param string $id Source ID
1359          * @param array $properties Source properties (see addSource())
1360          * @return string
1361          */
1362         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1363                 if ( is_array( $id ) ) {
1364                         return Xml::encodeJsCall(
1365                                 'mw.loader.addSource',
1366                                 array( $id ),
1367                                 ResourceLoader::inDebugMode()
1368                         );
1369                 } else {
1370                         return Xml::encodeJsCall(
1371                                 'mw.loader.addSource',
1372                                 array( $id, $properties ),
1373                                 ResourceLoader::inDebugMode()
1374                         );
1375                 }
1376         }
1377
1378         /**
1379          * Returns JS code which runs given JS code if the client-side framework is
1380          * present.
1381          *
1382          * @deprecated since 1.25; use makeInlineScript instead
1383          * @param string $script JavaScript code
1384          * @return string
1385          */
1386         public static function makeLoaderConditionalScript( $script ) {
1387                 return "window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n" .
1388                         trim( $script ) . "\n} );";
1389         }
1390
1391         /**
1392          * Construct an inline script tag with given JS code.
1393          *
1394          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1395          * only if the client has adequate support for MediaWiki JavaScript code.
1396          *
1397          * @param string $script JavaScript code
1398          * @return WrappedString HTML
1399          */
1400         public static function makeInlineScript( $script ) {
1401                 $js = self::makeLoaderConditionalScript( $script );
1402                 return new WrappedString(
1403                         Html::inlineScript( $js ),
1404                         "<script>window.RLQ = window.RLQ || []; window.RLQ.push( function () {\n",
1405                         "\n} );</script>"
1406                 );
1407         }
1408
1409         /**
1410          * Returns JS code which will set the MediaWiki configuration array to
1411          * the given value.
1412          *
1413          * @param array $configuration List of configuration values keyed by variable name
1414          * @return string
1415          */
1416         public static function makeConfigSetScript( array $configuration ) {
1417                 if ( ResourceLoader::inDebugMode() ) {
1418                         return Xml::encodeJsCall( 'mw.config.set', array( $configuration ), true );
1419                 }
1420
1421                 $config = RequestContext::getMain()->getConfig();
1422                 $js = Xml::encodeJsCall( 'mw.config.set', array( $configuration ), false );
1423                 return self::applyFilter( 'minify-js', $js, $config );
1424         }
1425
1426         /**
1427          * Convert an array of module names to a packed query string.
1428          *
1429          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1430          * becomes 'foo.bar,baz|bar.baz,quux'
1431          * @param array $modules List of module names (strings)
1432          * @return string Packed query string
1433          */
1434         public static function makePackedModulesString( $modules ) {
1435                 $groups = array(); // array( prefix => array( suffixes ) )
1436                 foreach ( $modules as $module ) {
1437                         $pos = strrpos( $module, '.' );
1438                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1439                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1440                         $groups[$prefix][] = $suffix;
1441                 }
1442
1443                 $arr = array();
1444                 foreach ( $groups as $prefix => $suffixes ) {
1445                         $p = $prefix === '' ? '' : $prefix . '.';
1446                         $arr[] = $p . implode( ',', $suffixes );
1447                 }
1448                 $str = implode( '|', $arr );
1449                 return $str;
1450         }
1451
1452         /**
1453          * Determine whether debug mode was requested
1454          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1455          * @return bool
1456          */
1457         public static function inDebugMode() {
1458                 if ( self::$debugMode === null ) {
1459                         global $wgRequest, $wgResourceLoaderDebug;
1460                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1461                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1462                         );
1463                 }
1464                 return self::$debugMode;
1465         }
1466
1467         /**
1468          * Reset static members used for caching.
1469          *
1470          * Global state and $wgRequest are evil, but we're using it right
1471          * now and sometimes we need to be able to force ResourceLoader to
1472          * re-evaluate the context because it has changed (e.g. in the test suite).
1473          */
1474         public static function clearCache() {
1475                 self::$debugMode = null;
1476         }
1477
1478         /**
1479          * Build a load.php URL
1480          *
1481          * @since 1.24
1482          * @param string $source Name of the ResourceLoader source
1483          * @param ResourceLoaderContext $context
1484          * @param array $extraQuery
1485          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1486          */
1487         public function createLoaderURL( $source, ResourceLoaderContext $context,
1488                 $extraQuery = array()
1489         ) {
1490                 $query = self::createLoaderQuery( $context, $extraQuery );
1491                 $script = $this->getLoadScript( $source );
1492
1493                 return wfAppendQuery( $script, $query );
1494         }
1495
1496         /**
1497          * Build a load.php URL
1498          * @deprecated since 1.24 Use createLoaderURL() instead
1499          * @param array $modules Array of module names (strings)
1500          * @param string $lang Language code
1501          * @param string $skin Skin name
1502          * @param string|null $user User name. If null, the &user= parameter is omitted
1503          * @param string|null $version Versioning timestamp
1504          * @param bool $debug Whether the request should be in debug mode
1505          * @param string|null $only &only= parameter
1506          * @param bool $printable Printable mode
1507          * @param bool $handheld Handheld mode
1508          * @param array $extraQuery Extra query parameters to add
1509          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1510          */
1511         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1512                 $version = null, $debug = false, $only = null, $printable = false,
1513                 $handheld = false, $extraQuery = array()
1514         ) {
1515                 global $wgLoadScript;
1516
1517                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1518                         $only, $printable, $handheld, $extraQuery
1519                 );
1520
1521                 return wfAppendQuery( $wgLoadScript, $query );
1522         }
1523
1524         /**
1525          * Helper for createLoaderURL()
1526          *
1527          * @since 1.24
1528          * @see makeLoaderQuery
1529          * @param ResourceLoaderContext $context
1530          * @param array $extraQuery
1531          * @return array
1532          */
1533         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1534                 return self::makeLoaderQuery(
1535                         $context->getModules(),
1536                         $context->getLanguage(),
1537                         $context->getSkin(),
1538                         $context->getUser(),
1539                         $context->getVersion(),
1540                         $context->getDebug(),
1541                         $context->getOnly(),
1542                         $context->getRequest()->getBool( 'printable' ),
1543                         $context->getRequest()->getBool( 'handheld' ),
1544                         $extraQuery
1545                 );
1546         }
1547
1548         /**
1549          * Build a query array (array representation of query string) for load.php. Helper
1550          * function for makeLoaderURL().
1551          *
1552          * @param array $modules
1553          * @param string $lang
1554          * @param string $skin
1555          * @param string $user
1556          * @param string $version
1557          * @param bool $debug
1558          * @param string $only
1559          * @param bool $printable
1560          * @param bool $handheld
1561          * @param array $extraQuery
1562          *
1563          * @return array
1564          */
1565         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1566                 $version = null, $debug = false, $only = null, $printable = false,
1567                 $handheld = false, $extraQuery = array()
1568         ) {
1569                 $query = array(
1570                         'modules' => self::makePackedModulesString( $modules ),
1571                         'lang' => $lang,
1572                         'skin' => $skin,
1573                         'debug' => $debug ? 'true' : 'false',
1574                 );
1575                 if ( $user !== null ) {
1576                         $query['user'] = $user;
1577                 }
1578                 if ( $version !== null ) {
1579                         $query['version'] = $version;
1580                 }
1581                 if ( $only !== null ) {
1582                         $query['only'] = $only;
1583                 }
1584                 if ( $printable ) {
1585                         $query['printable'] = 1;
1586                 }
1587                 if ( $handheld ) {
1588                         $query['handheld'] = 1;
1589                 }
1590                 $query += $extraQuery;
1591
1592                 // Make queries uniform in order
1593                 ksort( $query );
1594                 return $query;
1595         }
1596
1597         /**
1598          * Check a module name for validity.
1599          *
1600          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1601          * at most 255 bytes.
1602          *
1603          * @param string $moduleName Module name to check
1604          * @return bool Whether $moduleName is a valid module name
1605          */
1606         public static function isValidModuleName( $moduleName ) {
1607                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1608         }
1609
1610         /**
1611          * Returns LESS compiler set up for use with MediaWiki
1612          *
1613          * @since 1.22
1614          * @since 1.26 added $extraVars parameter
1615          * @param Config $config
1616          * @param array $extraVars Associative array of extra (i.e., other than the
1617          *   globally-configured ones) that should be used for compilation.
1618          * @throws MWException
1619          * @return Less_Parser
1620          */
1621         public static function getLessCompiler( Config $config, $extraVars = array() ) {
1622                 // When called from the installer, it is possible that a required PHP extension
1623                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1624                 // exception (caught by the installer) to prevent a fatal error later on.
1625                 if ( !class_exists( 'Less_Parser' ) ) {
1626                         throw new MWException( 'MediaWiki requires the less.php parser' );
1627                 }
1628
1629                 $parser = new Less_Parser;
1630                 $parser->ModifyVars( array_merge( self::getLessVars( $config ), $extraVars ) );
1631                 $parser->SetImportDirs( array_fill_keys( $config->get( 'ResourceLoaderLESSImportPaths' ), '' ) );
1632                 $parser->SetOption( 'relativeUrls', false );
1633                 $parser->SetCacheDir( $config->get( 'CacheDirectory' ) ?: wfTempDir() );
1634
1635                 return $parser;
1636         }
1637
1638         /**
1639          * Get global LESS variables.
1640          *
1641          * @param Config $config
1642          * @since 1.22
1643          * @return array Map of variable names to string CSS values.
1644          */
1645         public static function getLessVars( Config $config ) {
1646                 if ( !self::$lessVars ) {
1647                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1648                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1649                         self::$lessVars = $lessVars;
1650                 }
1651                 return self::$lessVars;
1652         }
1653 }