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 MediaWiki\MediaWikiServices;
  26 use Psr\Log\LoggerAwareInterface;
  27 use Psr\Log\LoggerInterface;
  28 use Psr\Log\NullLogger;
  29 use WrappedString\WrappedString;
  30
  31 /**
  32  * Dynamic JavaScript and CSS resource loading system.
  33  *
  34  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  35  *    https://www.mediawiki.org/wiki/ResourceLoader
  36  */
  37 class ResourceLoader implements LoggerAwareInterface {
  38         /** @var int */
  39         protected static $filterCacheVersion = 7;
  40
  41         /** @var bool */
  42         protected static $debugMode = null;
  43
  44         /** @var array */
  45         private $lessVars = null;
  46
  47         /**
  48          * Module name/ResourceLoaderModule object pairs
  49          * @var array
  50          */
  51         protected $modules = [];
  52
  53         /**
  54          * Associative array mapping module name to info associative array
  55          * @var array
  56          */
  57         protected $moduleInfos = [];
  58
  59         /** @var Config $config */
  60         protected $config;
  61
  62         /**
  63          * Associative array mapping framework ids to a list of names of test suite modules
  64          * like [ 'qunit' => [ 'mediawiki.tests.qunit.suites', 'ext.foo.tests', ... ], ... ]
  65          * @var array
  66          */
  67         protected $testModuleNames = [];
  68
  69         /**
  70          * E.g. [ 'source-id' => 'http://.../load.php' ]
  71          * @var array
  72          */
  73         protected $sources = [];
  74
  75         /**
  76          * Errors accumulated during current respond() call.
  77          * @var array
  78          */
  79         protected $errors = [];
  80
  81         /**
  82          * @var MessageBlobStore
  83          */
  84         protected $blobStore;
  85
  86         /**
  87          * @var LoggerInterface
  88          */
  89         private $logger;
  90
  91         /** @var string JavaScript / CSS pragma to disable minification. **/
  92         const FILTER_NOMIN = '/*@nomin*/';
  93
  94         /**
  95          * Load information stored in the database about modules.
  96          *
  97          * This method grabs modules dependencies from the database and updates modules
  98          * objects.
  99          *
 100          * This is not inside the module code because it is much faster to
 101          * request all of the information at once than it is to have each module
 102          * requests its own information. This sacrifice of modularity yields a substantial
 103          * performance improvement.
 104          *
 105          * @param array $moduleNames List of module names to preload information for
 106          * @param ResourceLoaderContext $context Context to load the information within
 107          */
 108         public function preloadModuleInfo( array $moduleNames, ResourceLoaderContext $context ) {
 109                 if ( !$moduleNames ) {
 110                         // Or else Database*::select() will explode, plus it's cheaper!
 111                         return;
 112                 }
 113                 $dbr = wfGetDB( DB_REPLICA );
 114                 $skin = $context->getSkin();
 115                 $lang = $context->getLanguage();
 116
 117                 // Batched version of ResourceLoaderModule::getFileDependencies
 118                 $vary = "$skin|$lang";
 119                 $res = $dbr->select( 'module_deps', [ 'md_module', 'md_deps' ], [
 120                                 'md_module' => $moduleNames,
 121                                 'md_skin' => $vary,
 122                         ], __METHOD__
 123                 );
 124
 125                 // Prime in-object cache for file dependencies
 126                 $modulesWithDeps = [];
 127                 foreach ( $res as $row ) {
 128                         $module = $this->getModule( $row->md_module );
 129                         if ( $module ) {
 130                                 $module->setFileDependencies( $context, ResourceLoaderModule::expandRelativePaths(
 131                                         FormatJson::decode( $row->md_deps, true )
 132                                 ) );
 133                                 $modulesWithDeps[] = $row->md_module;
 134                         }
 135                 }
 136                 // Register the absence of a dependency row too
 137                 foreach ( array_diff( $moduleNames, $modulesWithDeps ) as $name ) {
 138                         $module = $this->getModule( $name );
 139                         if ( $module ) {
 140                                 $this->getModule( $name )->setFileDependencies( $context, [] );
 141                         }
 142                 }
 143
 144                 // Batched version of ResourceLoaderWikiModule::getTitleInfo
 145                 ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $moduleNames );
 146
 147                 // Prime in-object cache for message blobs for modules with messages
 148                 $modules = [];
 149                 foreach ( $moduleNames as $name ) {
 150                         $module = $this->getModule( $name );
 151                         if ( $module && $module->getMessages() ) {
 152                                 $modules[$name] = $module;
 153                         }
 154                 }
 155                 $store = $this->getMessageBlobStore();
 156                 $blobs = $store->getBlobs( $modules, $lang );
 157                 foreach ( $blobs as $name => $blob ) {
 158                         $modules[$name]->setMessageBlob( $blob, $lang );
 159                 }
 160         }
 161
 162         /**
 163          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 164          *
 165          * Available filters are:
 166          *
 167          *    - minify-js \see JavaScriptMinifier::minify
 168          *    - minify-css \see CSSMin::minify
 169          *
 170          * If $data is empty, only contains whitespace or the filter was unknown,
 171          * $data is returned unmodified.
 172          *
 173          * @param string $filter Name of filter to run
 174          * @param string $data Text to filter, such as JavaScript or CSS text
 175          * @param array $options Keys:
 176          *  - (bool) cache: Whether to allow caching this data. Default: true.
 177          * @return string Filtered data, or a comment containing an error message
 178          */
 179         public static function filter( $filter, $data, array $options = [] ) {
 180                 if ( strpos( $data, ResourceLoader::FILTER_NOMIN ) !== false ) {
 181                         return $data;
 182                 }
 183
 184                 if ( isset( $options['cache'] ) && $options['cache'] === false ) {
 185                         return self::applyFilter( $filter, $data );
 186                 }
 187
 188                 $stats = RequestContext::getMain()->getStats();
 189                 $cache = ObjectCache::getLocalServerInstance( CACHE_ANYTHING );
 190
 191                 $key = $cache->makeGlobalKey(
 192                         'resourceloader',
 193                         'filter',
 194                         $filter,
 195                         self::$filterCacheVersion, md5( $data )
 196                 );
 197
 198                 $result = $cache->get( $key );
 199                 if ( $result === false ) {
 200                         $stats->increment( "resourceloader_cache.$filter.miss" );
 201                         $result = self::applyFilter( $filter, $data );
 202                         $cache->set( $key, $result, 24 * 3600 );
 203                 } else {
 204                         $stats->increment( "resourceloader_cache.$filter.hit" );
 205                 }
 206                 if ( $result === null ) {
 207                         // Cached failure
 208                         $result = $data;
 209                 }
 210
 211                 return $result;
 212         }
 213
 214         private static function applyFilter( $filter, $data ) {
 215                 $data = trim( $data );
 216                 if ( $data ) {
 217                         try {
 218                                 $data = ( $filter === 'minify-css' )
 219                                         ? CSSMin::minify( $data )
 220                                         : JavaScriptMinifier::minify( $data );
 221                         } catch ( Exception $e ) {
 222                                 MWExceptionHandler::logException( $e );
 223                                 return null;
 224                         }
 225                 }
 226                 return $data;
 227         }
 228
 229         /* Methods */
 230
 231         /**
 232          * Register core modules and runs registration hooks.
 233          * @param Config $config [optional]
 234          * @param LoggerInterface $logger [optional]
 235          */
 236         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 237                 global $IP;
 238
 239                 $this->logger = $logger ?: new NullLogger();
 240
 241                 if ( !$config ) {
 242                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 243                         $config = MediaWikiServices::getInstance()->getMainConfig();
 244                 }
 245                 $this->config = $config;
 246
 247                 // Add 'local' source first
 248                 $this->addSource( 'local', $config->get( 'LoadScript' ) );
 249
 250                 // Add other sources
 251                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 252
 253                 // Register core modules
 254                 $this->register( include "$IP/resources/Resources.php" );
 255                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 256                 // Register extension modules
 257                 $this->register( $config->get( 'ResourceModules' ) );
 258                 Hooks::run( 'ResourceLoaderRegisterModules', [ &$this ] );
 259
 260                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 261                         $this->registerTestModules();
 262                 }
 263
 264                 $this->setMessageBlobStore( new MessageBlobStore( $this, $this->logger ) );
 265         }
 266
 267         /**
 268          * @return Config
 269          */
 270         public function getConfig() {
 271                 return $this->config;
 272         }
 273
 274         /**
 275          * @since 1.26
 276          * @param LoggerInterface $logger
 277          */
 278         public function setLogger( LoggerInterface $logger ) {
 279                 $this->logger = $logger;
 280         }
 281
 282         /**
 283          * @since 1.27
 284          * @return LoggerInterface
 285          */
 286         public function getLogger() {
 287                 return $this->logger;
 288         }
 289
 290         /**
 291          * @since 1.26
 292          * @return MessageBlobStore
 293          */
 294         public function getMessageBlobStore() {
 295                 return $this->blobStore;
 296         }
 297
 298         /**
 299          * @since 1.25
 300          * @param MessageBlobStore $blobStore
 301          */
 302         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 303                 $this->blobStore = $blobStore;
 304         }
 305
 306         /**
 307          * Register a module with the ResourceLoader system.
 308          *
 309          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 310          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 311          *   this may also be a ResourceLoaderModule object. Optional when using
 312          *   multiple-registration calling style.
 313          * @throws MWException If a duplicate module registration is attempted
 314          * @throws MWException If a module name contains illegal characters (pipes or commas)
 315          * @throws MWException If something other than a ResourceLoaderModule is being registered
 316          * @return bool False if there were any errors, in which case one or more modules were
 317          *   not registered
 318          */
 319         public function register( $name, $info = null ) {
 320                 $moduleSkinStyles = $this->config->get( 'ResourceModuleSkinStyles' );
 321
 322                 // Allow multiple modules to be registered in one call
 323                 $registrations = is_array( $name ) ? $name : [ $name => $info ];
 324                 foreach ( $registrations as $name => $info ) {
 325                         // Warn on duplicate registrations
 326                         if ( isset( $this->moduleInfos[$name] ) ) {
 327                                 // A module has already been registered by this name
 328                                 $this->logger->warning(
 329                                         'ResourceLoader duplicate registration warning. ' .
 330                                         'Another module has already been registered as ' . $name
 331                                 );
 332                         }
 333
 334                         // Check $name for validity
 335                         if ( !self::isValidModuleName( $name ) ) {
 336                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 337                                         . "see ResourceLoader::isValidModuleName()" );
 338                         }
 339
 340                         // Attach module
 341                         if ( $info instanceof ResourceLoaderModule ) {
 342                                 $this->moduleInfos[$name] = [ 'object' => $info ];
 343                                 $info->setName( $name );
 344                                 $this->modules[$name] = $info;
 345                         } elseif ( is_array( $info ) ) {
 346                                 // New calling convention
 347                                 $this->moduleInfos[$name] = $info;
 348                         } else {
 349                                 throw new MWException(
 350                                         'ResourceLoader module info type error for module \'' . $name .
 351                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 352                                 );
 353                         }
 354
 355                         // Last-minute changes
 356
 357                         // Apply custom skin-defined styles to existing modules.
 358                         if ( $this->isFileModule( $name ) ) {
 359                                 foreach ( $moduleSkinStyles as $skinName => $skinStyles ) {
 360                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 361                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 362                                                 continue;
 363                                         }
 364
 365                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 366                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 367                                         if ( isset( $skinStyles[$name] ) ) {
 368                                                 $paths = (array)$skinStyles[$name];
 369                                                 $styleFiles = [];
 370                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 371                                                 $paths = (array)$skinStyles['+' . $name];
 372                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 373                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 374                                                         [];
 375                                         } else {
 376                                                 continue;
 377                                         }
 378
 379                                         // Add new file paths, remapping them to refer to our directories and not use settings
 380                                         // from the module we're modifying, which come from the base definition.
 381                                         list( $localBasePath, $remoteBasePath ) =
 382                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 383
 384                                         foreach ( $paths as $path ) {
 385                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 386                                         }
 387
 388                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 389                                 }
 390                         }
 391                 }
 392         }
 393
 394         public function registerTestModules() {
 395                 global $IP;
 396
 397                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 398                         throw new MWException( 'Attempt to register JavaScript test modules '
 399                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 400                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 401                 }
 402
 403                 // Get core test suites
 404                 $testModules = [];
 405                 $testModules['qunit'] = [];
 406                 // Get other test suites (e.g. from extensions)
 407                 Hooks::run( 'ResourceLoaderTestModules', [ &$testModules, &$this ] );
 408
 409                 // Add the testrunner (which configures QUnit) to the dependencies.
 410                 // Since it must be ready before any of the test suites are executed.
 411                 foreach ( $testModules['qunit'] as &$module ) {
 412                         // Make sure all test modules are top-loading so that when QUnit starts
 413                         // on document-ready, it will run once and finish. If some tests arrive
 414                         // later (possibly after QUnit has already finished) they will be ignored.
 415                         $module['position'] = 'top';
 416                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 417                 }
 418
 419                 $testModules['qunit'] =
 420                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 421
 422                 foreach ( $testModules as $id => $names ) {
 423                         // Register test modules
 424                         $this->register( $testModules[$id] );
 425
 426                         // Keep track of their names so that they can be loaded together
 427                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 428                 }
 429         }
 430
 431         /**
 432          * Add a foreign source of modules.
 433          *
 434          * Source IDs are typically the same as the Wiki ID or database name (e.g. lowercase a-z).
 435          *
 436          * @param array|string $id Source ID (string), or [ id1 => loadUrl, id2 => loadUrl, ... ]
 437          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 438          *  backwards-compatibility.
 439          * @throws MWException
 440          */
 441         public function addSource( $id, $loadUrl = null ) {
 442                 // Allow multiple sources to be registered in one call
 443                 if ( is_array( $id ) ) {
 444                         foreach ( $id as $key => $value ) {
 445                                 $this->addSource( $key, $value );
 446                         }
 447                         return;
 448                 }
 449
 450                 // Disallow duplicates
 451                 if ( isset( $this->sources[$id] ) ) {
 452                         throw new MWException(
 453                                 'ResourceLoader duplicate source addition error. ' .
 454                                 'Another source has already been registered as ' . $id
 455                         );
 456                 }
 457
 458                 // Pre 1.24 backwards-compatibility
 459                 if ( is_array( $loadUrl ) ) {
 460                         if ( !isset( $loadUrl['loadScript'] ) ) {
 461                                 throw new MWException(
 462                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 463                                 );
 464                         }
 465
 466                         $loadUrl = $loadUrl['loadScript'];
 467                 }
 468
 469                 $this->sources[$id] = $loadUrl;
 470         }
 471
 472         /**
 473          * Get a list of module names.
 474          *
 475          * @return array List of module names
 476          */
 477         public function getModuleNames() {
 478                 return array_keys( $this->moduleInfos );
 479         }
 480
 481         /**
 482          * Get a list of test module names for one (or all) frameworks.
 483          *
 484          * If the given framework id is unknkown, or if the in-object variable is not an array,
 485          * then it will return an empty array.
 486          *
 487          * @param string $framework Get only the test module names for one
 488          *   particular framework (optional)
 489          * @return array
 490          */
 491         public function getTestModuleNames( $framework = 'all' ) {
 492                 /** @todo api siteinfo prop testmodulenames modulenames */
 493                 if ( $framework == 'all' ) {
 494                         return $this->testModuleNames;
 495                 } elseif ( isset( $this->testModuleNames[$framework] )
 496                         && is_array( $this->testModuleNames[$framework] )
 497                 ) {
 498                         return $this->testModuleNames[$framework];
 499                 } else {
 500                         return [];
 501                 }
 502         }
 503
 504         /**
 505          * Check whether a ResourceLoader module is registered
 506          *
 507          * @since 1.25
 508          * @param string $name
 509          * @return bool
 510          */
 511         public function isModuleRegistered( $name ) {
 512                 return isset( $this->moduleInfos[$name] );
 513         }
 514
 515         /**
 516          * Get the ResourceLoaderModule object for a given module name.
 517          *
 518          * If an array of module parameters exists but a ResourceLoaderModule object has not
 519          * yet been instantiated, this method will instantiate and cache that object such that
 520          * subsequent calls simply return the same object.
 521          *
 522          * @param string $name Module name
 523          * @return ResourceLoaderModule|null If module has been registered, return a
 524          *  ResourceLoaderModule instance. Otherwise, return null.
 525          */
 526         public function getModule( $name ) {
 527                 if ( !isset( $this->modules[$name] ) ) {
 528                         if ( !isset( $this->moduleInfos[$name] ) ) {
 529                                 // No such module
 530                                 return null;
 531                         }
 532                         // Construct the requested object
 533                         $info = $this->moduleInfos[$name];
 534                         /** @var ResourceLoaderModule $object */
 535                         if ( isset( $info['object'] ) ) {
 536                                 // Object given in info array
 537                                 $object = $info['object'];
 538                         } else {
 539                                 if ( !isset( $info['class'] ) ) {
 540                                         $class = 'ResourceLoaderFileModule';
 541                                 } else {
 542                                         $class = $info['class'];
 543                                 }
 544                                 /** @var ResourceLoaderModule $object */
 545                                 $object = new $class( $info );
 546                                 $object->setConfig( $this->getConfig() );
 547                                 $object->setLogger( $this->logger );
 548                         }
 549                         $object->setName( $name );
 550                         $this->modules[$name] = $object;
 551                 }
 552
 553                 return $this->modules[$name];
 554         }
 555
 556         /**
 557          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 558          *
 559          * @param string $name Module name
 560          * @return bool
 561          */
 562         protected function isFileModule( $name ) {
 563                 if ( !isset( $this->moduleInfos[$name] ) ) {
 564                         return false;
 565                 }
 566                 $info = $this->moduleInfos[$name];
 567                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 568                         return false;
 569                 }
 570                 return true;
 571         }
 572
 573         /**
 574          * Get the list of sources.
 575          *
 576          * @return array Like [ id => load.php url, ... ]
 577          */
 578         public function getSources() {
 579                 return $this->sources;
 580         }
 581
 582         /**
 583          * Get the URL to the load.php endpoint for the given
 584          * ResourceLoader source
 585          *
 586          * @since 1.24
 587          * @param string $source
 588          * @throws MWException On an invalid $source name
 589          * @return string
 590          */
 591         public function getLoadScript( $source ) {
 592                 if ( !isset( $this->sources[$source] ) ) {
 593                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 594                 }
 595                 return $this->sources[$source];
 596         }
 597
 598         /**
 599          * @since 1.26
 600          * @param string $value
 601          * @return string Hash
 602          */
 603         public static function makeHash( $value ) {
 604                 $hash = hash( 'fnv132', $value );
 605                 return Wikimedia\base_convert( $hash, 16, 36, 7 );
 606         }
 607
 608         /**
 609          * Helper method to get and combine versions of multiple modules.
 610          *
 611          * @since 1.26
 612          * @param ResourceLoaderContext $context
 613          * @param string[] $modules List of known module names
 614          * @return string Hash
 615          */
 616         public function getCombinedVersion( ResourceLoaderContext $context, array $moduleNames ) {
 617                 if ( !$moduleNames ) {
 618                         return '';
 619                 }
 620                 $hashes = array_map( function ( $module ) use ( $context ) {
 621                         try {
 622                                 return $this->getModule( $module )->getVersionHash( $context );
 623                         } catch ( Exception $e ) {
 624                                 // If modules fail to compute a version, do still consider the versions
 625                                 // of other modules - don't set an empty string E-Tag for the whole request.
 626                                 // See also T152266 and StartupModule::getModuleRegistrations().
 627                                 MWExceptionHandler::logException( $e );
 628                                 $this->logger->warning(
 629                                         'Calculating version for "{module}" failed: {exception}',
 630                                         [
 631                                                 'module' => $module,
 632                                                 'exception' => $e,
 633                                         ]
 634                                 );
 635                                 $this->errors[] = self::formatExceptionNoComment( $e );
 636                                 return '';
 637                         }
 638                 }, $moduleNames );
 639                 return self::makeHash( implode( '', $hashes ) );
 640         }
 641
 642         /**
 643          * Get the expected value of the 'version' query parameter.
 644          *
 645          * This is used by respond() to set a short Cache-Control header for requests with
 646          * information newer than the current server has. This avoids pollution of edge caches.
 647          * Typically during deployment. (T117587)
 648          *
 649          * This MUST match return value of `mw.loader#getCombinedVersion()` client-side.
 650          *
 651          * @since 1.28
 652          * @param ResourceLoaderContext $context
 653          * @param string[] $modules List of module names
 654          * @return string Hash
 655          */
 656         public function makeVersionQuery( ResourceLoaderContext $context ) {
 657                 // As of MediaWiki 1.28, the server and client use the same algorithm for combining
 658                 // version hashes. There is no technical reason for this to be same, and for years the
 659                 // implementations differed. If getCombinedVersion in PHP (used for StartupModule and
 660                 // E-Tag headers) differs in the future from getCombinedVersion in JS (used for 'version'
 661                 // query parameter), then this method must continue to match the JS one.
 662                 $moduleNames = [];
 663                 foreach ( $context->getModules() as $name ) {
 664                         if ( !$this->getModule( $name ) ) {
 665                                 // If a versioned request contains a missing module, the version is a mismatch
 666                                 // as the client considered a module (and version) we don't have.
 667                                 return '';
 668                         }
 669                         $moduleNames[] = $name;
 670                 }
 671                 return $this->getCombinedVersion( $context, $moduleNames );
 672         }
 673
 674         /**
 675          * Output a response to a load request, including the content-type header.
 676          *
 677          * @param ResourceLoaderContext $context Context in which a response should be formed
 678          */
 679         public function respond( ResourceLoaderContext $context ) {
 680                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 681                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 682                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 683                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 684                 // the whole thing in our own output buffer to be sure the active buffer
 685                 // doesn't use ob_gzhandler.
 686                 // See https://bugs.php.net/bug.php?id=36514
 687                 ob_start();
 688
 689                 // Find out which modules are missing and instantiate the others
 690                 $modules = [];
 691                 $missing = [];
 692                 foreach ( $context->getModules() as $name ) {
 693                         $module = $this->getModule( $name );
 694                         if ( $module ) {
 695                                 // Do not allow private modules to be loaded from the web.
 696                                 // This is a security issue, see bug 34907.
 697                                 if ( $module->getGroup() === 'private' ) {
 698                                         $this->logger->debug( "Request for private module '$name' denied" );
 699                                         $this->errors[] = "Cannot show private module \"$name\"";
 700                                         continue;
 701                                 }
 702                                 $modules[$name] = $module;
 703                         } else {
 704                                 $missing[] = $name;
 705                         }
 706                 }
 707
 708                 try {
 709                         // Preload for getCombinedVersion() and for batch makeModuleResponse()
 710                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 711                 } catch ( Exception $e ) {
 712                         MWExceptionHandler::logException( $e );
 713                         $this->logger->warning( 'Preloading module info failed: {exception}', [
 714                                 'exception' => $e
 715                         ] );
 716                         $this->errors[] = self::formatExceptionNoComment( $e );
 717                 }
 718
 719                 // Combine versions to propagate cache invalidation
 720                 $versionHash = '';
 721                 try {
 722                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 723                 } catch ( Exception $e ) {
 724                         MWExceptionHandler::logException( $e );
 725                         $this->logger->warning( 'Calculating version hash failed: {exception}', [
 726                                 'exception' => $e
 727                         ] );
 728                         $this->errors[] = self::formatExceptionNoComment( $e );
 729                 }
 730
 731                 // See RFC 2616 § 3.11 Entity Tags
 732                 // https://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 733                 $etag = 'W/"' . $versionHash . '"';
 734
 735                 // Try the client-side cache first
 736                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 737                         return; // output handled (buffers cleared)
 738                 }
 739
 740                 // Use file cache if enabled and available...
 741                 if ( $this->config->get( 'UseFileCache' ) ) {
 742                         $fileCache = ResourceFileCache::newFromContext( $context );
 743                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 744                                 return; // output handled
 745                         }
 746                 }
 747
 748                 // Generate a response
 749                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 750
 751                 // Capture any PHP warnings from the output buffer and append them to the
 752                 // error list if we're in debug mode.
 753                 if ( $context->getDebug() ) {
 754                         $warnings = ob_get_contents();
 755                         if ( strlen( $warnings ) ) {
 756                                 $this->errors[] = $warnings;
 757                         }
 758                 }
 759
 760                 // Save response to file cache unless there are errors
 761                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 762                         // Cache single modules and images...and other requests if there are enough hits
 763                         if ( ResourceFileCache::useFileCache( $context ) ) {
 764                                 if ( $fileCache->isCacheWorthy() ) {
 765                                         $fileCache->saveText( $response );
 766                                 } else {
 767                                         $fileCache->incrMissesRecent( $context->getRequest() );
 768                                 }
 769                         }
 770                 }
 771
 772                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 773
 774                 // Remove the output buffer and output the response
 775                 ob_end_clean();
 776
 777                 if ( $context->getImageObj() && $this->errors ) {
 778                         // We can't show both the error messages and the response when it's an image.
 779                         $response = implode( "\n\n", $this->errors );
 780                 } elseif ( $this->errors ) {
 781                         $errorText = implode( "\n\n", $this->errors );
 782                         $errorResponse = self::makeComment( $errorText );
 783                         if ( $context->shouldIncludeScripts() ) {
 784                                 $errorResponse .= 'if (window.console && console.error) {'
 785                                         . Xml::encodeJsCall( 'console.error', [ $errorText ] )
 786                                         . "}\n";
 787                         }
 788
 789                         // Prepend error info to the response
 790                         $response = $errorResponse . $response;
 791                 }
 792
 793                 $this->errors = [];
 794                 echo $response;
 795         }
 796
 797         /**
 798          * Send main response headers to the client.
 799          *
 800          * Deals with Content-Type, CORS (for stylesheets), and caching.
 801          *
 802          * @param ResourceLoaderContext $context
 803          * @param string $etag ETag header value
 804          * @param bool $errors Whether there are errors in the response
 805          * @return void
 806          */
 807         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 808                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 809                 // Use a short cache expiry so that updates propagate to clients quickly, if:
 810                 // - No version specified (shared resources, e.g. stylesheets)
 811                 // - There were errors (recover quickly)
 812                 // - Version mismatch (T117587, T47877)
 813                 if ( is_null( $context->getVersion() )
 814                         || $errors
 815                         || $context->getVersion() !== $this->makeVersionQuery( $context )
 816                 ) {
 817                         $maxage = $rlMaxage['unversioned']['client'];
 818                         $smaxage = $rlMaxage['unversioned']['server'];
 819                 // If a version was specified we can use a longer expiry time since changing
 820                 // version numbers causes cache misses
 821                 } else {
 822                         $maxage = $rlMaxage['versioned']['client'];
 823                         $smaxage = $rlMaxage['versioned']['server'];
 824                 }
 825                 if ( $context->getImageObj() ) {
 826                         // Output different headers if we're outputting textual errors.
 827                         if ( $errors ) {
 828                                 header( 'Content-Type: text/plain; charset=utf-8' );
 829                         } else {
 830                                 $context->getImageObj()->sendResponseHeaders( $context );
 831                         }
 832                 } elseif ( $context->getOnly() === 'styles' ) {
 833                         header( 'Content-Type: text/css; charset=utf-8' );
 834                         header( 'Access-Control-Allow-Origin: *' );
 835                 } else {
 836                         header( 'Content-Type: text/javascript; charset=utf-8' );
 837                 }
 838                 // See RFC 2616 § 14.19 ETag
 839                 // https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 840                 header( 'ETag: ' . $etag );
 841                 if ( $context->getDebug() ) {
 842                         // Do not cache debug responses
 843                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 844                         header( 'Pragma: no-cache' );
 845                 } else {
 846                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 847                         $exp = min( $maxage, $smaxage );
 848                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 849                 }
 850         }
 851
 852         /**
 853          * Respond with HTTP 304 Not Modified if appropiate.
 854          *
 855          * If there's an If-None-Match header, respond with a 304 appropriately
 856          * and clear out the output buffer. If the client cache is too old then do nothing.
 857          *
 858          * @param ResourceLoaderContext $context
 859          * @param string $etag ETag header value
 860          * @return bool True if HTTP 304 was sent and output handled
 861          */
 862         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 863                 // See RFC 2616 § 14.26 If-None-Match
 864                 // https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 865                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 866                 // Never send 304s in debug mode
 867                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 868                         // There's another bug in ob_gzhandler (see also the comment at
 869                         // the top of this function) that causes it to gzip even empty
 870                         // responses, meaning it's impossible to produce a truly empty
 871                         // response (because the gzip header is always there). This is
 872                         // a problem because 304 responses have to be completely empty
 873                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 874                         // See also https://bugs.php.net/bug.php?id=51579
 875                         // To work around this, we tear down all output buffering before
 876                         // sending the 304.
 877                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 878
 879                         HttpStatus::header( 304 );
 880
 881                         $this->sendResponseHeaders( $context, $etag, false );
 882                         return true;
 883                 }
 884                 return false;
 885         }
 886
 887         /**
 888          * Send out code for a response from file cache if possible.
 889          *
 890          * @param ResourceFileCache $fileCache Cache object for this request URL
 891          * @param ResourceLoaderContext $context Context in which to generate a response
 892          * @param string $etag ETag header value
 893          * @return bool If this found a cache file and handled the response
 894          */
 895         protected function tryRespondFromFileCache(
 896                 ResourceFileCache $fileCache,
 897                 ResourceLoaderContext $context,
 898                 $etag
 899         ) {
 900                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 901                 // Buffer output to catch warnings.
 902                 ob_start();
 903                 // Get the maximum age the cache can be
 904                 $maxage = is_null( $context->getVersion() )
 905                         ? $rlMaxage['unversioned']['server']
 906                         : $rlMaxage['versioned']['server'];
 907                 // Minimum timestamp the cache file must have
 908                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 909                 if ( !$good ) {
 910                         try { // RL always hits the DB on file cache miss...
 911                                 wfGetDB( DB_REPLICA );
 912                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 913                                 $good = $fileCache->isCacheGood(); // cache existence check
 914                         }
 915                 }
 916                 if ( $good ) {
 917                         $ts = $fileCache->cacheTimestamp();
 918                         // Send content type and cache headers
 919                         $this->sendResponseHeaders( $context, $etag, false );
 920                         $response = $fileCache->fetchText();
 921                         // Capture any PHP warnings from the output buffer and append them to the
 922                         // response in a comment if we're in debug mode.
 923                         if ( $context->getDebug() ) {
 924                                 $warnings = ob_get_contents();
 925                                 if ( strlen( $warnings ) ) {
 926                                         $response = self::makeComment( $warnings ) . $response;
 927                                 }
 928                         }
 929                         // Remove the output buffer and output the response
 930                         ob_end_clean();
 931                         echo $response . "\n/* Cached {$ts} */";
 932                         return true; // cache hit
 933                 }
 934                 // Clear buffer
 935                 ob_end_clean();
 936
 937                 return false; // cache miss
 938         }
 939
 940         /**
 941          * Generate a CSS or JS comment block.
 942          *
 943          * Only use this for public data, not error message details.
 944          *
 945          * @param string $text
 946          * @return string
 947          */
 948         public static function makeComment( $text ) {
 949                 $encText = str_replace( '*/', '* /', $text );
 950                 return "/*\n$encText\n*/\n";
 951         }
 952
 953         /**
 954          * Handle exception display.
 955          *
 956          * @param Exception $e Exception to be shown to the user
 957          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 958          */
 959         public static function formatException( $e ) {
 960                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 961         }
 962
 963         /**
 964          * Handle exception display.
 965          *
 966          * @since 1.25
 967          * @param Exception $e Exception to be shown to the user
 968          * @return string Sanitized text that can be returned to the user
 969          */
 970         protected static function formatExceptionNoComment( $e ) {
 971                 global $wgShowExceptionDetails;
 972
 973                 if ( !$wgShowExceptionDetails ) {
 974                         return MWExceptionHandler::getPublicLogMessage( $e );
 975                 }
 976
 977                 return MWExceptionHandler::getLogMessage( $e );
 978         }
 979
 980         /**
 981          * Generate code for a response.
 982          *
 983          * @param ResourceLoaderContext $context Context in which to generate a response
 984          * @param ResourceLoaderModule[] $modules List of module objects keyed by module name
 985          * @param string[] $missing List of requested module names that are unregistered (optional)
 986          * @return string Response data
 987          */
 988         public function makeModuleResponse( ResourceLoaderContext $context,
 989                 array $modules, array $missing = []
 990         ) {
 991                 $out = '';
 992                 $states = [];
 993
 994                 if ( !count( $modules ) && !count( $missing ) ) {
 995                         return <<<MESSAGE
 996 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 997    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 998    no modules were requested. Max made me put this here. */
 999 MESSAGE;
1000                 }
1001
1002                 $image = $context->getImageObj();
1003                 if ( $image ) {
1004                         $data = $image->getImageData( $context );
1005                         if ( $data === false ) {
1006                                 $data = '';
1007                                 $this->errors[] = 'Image generation failed';
1008                         }
1009                         return $data;
1010                 }
1011
1012                 foreach ( $missing as $name ) {
1013                         $states[$name] = 'missing';
1014                 }
1015
1016                 // Generate output
1017                 $isRaw = false;
1018
1019                 $filter = $context->getOnly() === 'styles' ? 'minify-css' : 'minify-js';
1020
1021                 foreach ( $modules as $name => $module ) {
1022                         try {
1023                                 $content = $module->getModuleContent( $context );
1024                                 $implementKey = $name . '@' . $module->getVersionHash( $context );
1025                                 $strContent = '';
1026
1027                                 // Append output
1028                                 switch ( $context->getOnly() ) {
1029                                         case 'scripts':
1030                                                 $scripts = $content['scripts'];
1031                                                 if ( is_string( $scripts ) ) {
1032                                                         // Load scripts raw...
1033                                                         $strContent = $scripts;
1034                                                 } elseif ( is_array( $scripts ) ) {
1035                                                         // ...except when $scripts is an array of URLs
1036                                                         $strContent = self::makeLoaderImplementScript( $implementKey, $scripts, [], [], [] );
1037                                                 }
1038                                                 break;
1039                                         case 'styles':
1040                                                 $styles = $content['styles'];
1041                                                 // We no longer seperate into media, they are all combined now with
1042                                                 // custom media type groups into @media .. {} sections as part of the css string.
1043                                                 // Module returns either an empty array or a numerical array with css strings.
1044                                                 $strContent = isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1045                                                 break;
1046                                         default:
1047                                                 $scripts = isset( $content['scripts'] ) ? $content['scripts'] : '';
1048                                                 if ( is_string( $scripts ) ) {
1049                                                         if ( $name === 'site' || $name === 'user' ) {
1050                                                                 // Legacy scripts that run in the global scope without a closure.
1051                                                                 // mw.loader.implement will use globalEval if scripts is a string.
1052                                                                 // Minify manually here, because general response minification is
1053                                                                 // not effective due it being a string literal, not a function.
1054                                                                 if ( !ResourceLoader::inDebugMode() ) {
1055                                                                         $scripts = self::filter( 'minify-js', $scripts ); // T107377
1056                                                                 }
1057                                                         } else {
1058                                                                 $scripts = new XmlJsCode( $scripts );
1059                                                         }
1060                                                 }
1061                                                 $strContent = self::makeLoaderImplementScript(
1062                                                         $implementKey,
1063                                                         $scripts,
1064                                                         isset( $content['styles'] ) ? $content['styles'] : [],
1065                                                         isset( $content['messagesBlob'] ) ? new XmlJsCode( $content['messagesBlob'] ) : [],
1066                                                         isset( $content['templates'] ) ? $content['templates'] : []
1067                                                 );
1068                                                 break;
1069                                 }
1070
1071                                 if ( !$context->getDebug() ) {
1072                                         $strContent = self::filter( $filter, $strContent );
1073                                 }
1074
1075                                 $out .= $strContent;
1076
1077                         } catch ( Exception $e ) {
1078                                 MWExceptionHandler::logException( $e );
1079                                 $this->logger->warning( 'Generating module package failed: {exception}', [
1080                                         'exception' => $e
1081                                 ] );
1082                                 $this->errors[] = self::formatExceptionNoComment( $e );
1083
1084                                 // Respond to client with error-state instead of module implementation
1085                                 $states[$name] = 'error';
1086                                 unset( $modules[$name] );
1087                         }
1088                         $isRaw |= $module->isRaw();
1089                 }
1090
1091                 // Update module states
1092                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1093                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1094                                 // Set the state of modules loaded as only scripts to ready as
1095                                 // they don't have an mw.loader.implement wrapper that sets the state
1096                                 foreach ( $modules as $name => $module ) {
1097                                         $states[$name] = 'ready';
1098                                 }
1099                         }
1100
1101                         // Set the state of modules we didn't respond to with mw.loader.implement
1102                         if ( count( $states ) ) {
1103                                 $stateScript = self::makeLoaderStateScript( $states );
1104                                 if ( !$context->getDebug() ) {
1105                                         $stateScript = self::filter( 'minify-js', $stateScript );
1106                                 }
1107                                 $out .= $stateScript;
1108                         }
1109                 } else {
1110                         if ( count( $states ) ) {
1111                                 $this->errors[] = 'Problematic modules: ' .
1112                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1113                         }
1114                 }
1115
1116                 return $out;
1117         }
1118
1119         /**
1120          * Get names of modules that use a certain message.
1121          *
1122          * @param string $messageKey
1123          * @return array List of module names
1124          */
1125         public function getModulesByMessage( $messageKey ) {
1126                 $moduleNames = [];
1127                 foreach ( $this->getModuleNames() as $moduleName ) {
1128                         $module = $this->getModule( $moduleName );
1129                         if ( in_array( $messageKey, $module->getMessages() ) ) {
1130                                 $moduleNames[] = $moduleName;
1131                         }
1132                 }
1133                 return $moduleNames;
1134         }
1135
1136         /* Static Methods */
1137
1138         /**
1139          * Return JS code that calls mw.loader.implement with given module properties.
1140          *
1141          * @param string $name Module name or implement key (format "`[name]@[version]`")
1142          * @param XmlJsCode|array|string $scripts Code as XmlJsCode (to be wrapped in a closure),
1143          *  list of URLs to JavaScript files, or a string of JavaScript for `$.globalEval`.
1144          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1145          *   to CSS files keyed by media type
1146          * @param mixed $messages List of messages associated with this module. May either be an
1147          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1148          *   the same data, wrapped in an XmlJsCode object.
1149          * @param array $templates Keys are name of templates and values are the source of
1150          *   the template.
1151          * @throws MWException
1152          * @return string
1153          */
1154         protected static function makeLoaderImplementScript(
1155                 $name, $scripts, $styles, $messages, $templates
1156         ) {
1157                 if ( $scripts instanceof XmlJsCode ) {
1158                         $scripts = new XmlJsCode( "function ( $, jQuery, require, module ) {\n{$scripts->value}\n}" );
1159                 } elseif ( !is_string( $scripts ) && !is_array( $scripts ) ) {
1160                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1161                 }
1162                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1163                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1164                 // of "{}". Force them to objects.
1165                 $module = [
1166                         $name,
1167                         $scripts,
1168                         (object)$styles,
1169                         (object)$messages,
1170                         (object)$templates,
1171                 ];
1172                 self::trimArray( $module );
1173
1174                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1175         }
1176
1177         /**
1178          * Returns JS code which, when called, will register a given list of messages.
1179          *
1180          * @param mixed $messages Either an associative array mapping message key to value, or a
1181          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1182          * @return string
1183          */
1184         public static function makeMessageSetScript( $messages ) {
1185                 return Xml::encodeJsCall(
1186                         'mw.messages.set',
1187                         [ (object)$messages ],
1188                         ResourceLoader::inDebugMode()
1189                 );
1190         }
1191
1192         /**
1193          * Combines an associative array mapping media type to CSS into a
1194          * single stylesheet with "@media" blocks.
1195          *
1196          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1197          * @return array
1198          */
1199         public static function makeCombinedStyles( array $stylePairs ) {
1200                 $out = [];
1201                 foreach ( $stylePairs as $media => $styles ) {
1202                         // ResourceLoaderFileModule::getStyle can return the styles
1203                         // as a string or an array of strings. This is to allow separation in
1204                         // the front-end.
1205                         $styles = (array)$styles;
1206                         foreach ( $styles as $style ) {
1207                                 $style = trim( $style );
1208                                 // Don't output an empty "@media print { }" block (bug 40498)
1209                                 if ( $style !== '' ) {
1210                                         // Transform the media type based on request params and config
1211                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1212                                         $media = OutputPage::transformCssMedia( $media );
1213
1214                                         if ( $media === '' || $media == 'all' ) {
1215                                                 $out[] = $style;
1216                                         } elseif ( is_string( $media ) ) {
1217                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1218                                         }
1219                                         // else: skip
1220                                 }
1221                         }
1222                 }
1223                 return $out;
1224         }
1225
1226         /**
1227          * Returns a JS call to mw.loader.state, which sets the state of a
1228          * module or modules to a given value. Has two calling conventions:
1229          *
1230          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1231          *         Set the state of a single module called $name to $state
1232          *
1233          *    - ResourceLoader::makeLoaderStateScript( [ $name => $state, ... ] ):
1234          *         Set the state of modules with the given names to the given states
1235          *
1236          * @param string $name
1237          * @param string $state
1238          * @return string
1239          */
1240         public static function makeLoaderStateScript( $name, $state = null ) {
1241                 if ( is_array( $name ) ) {
1242                         return Xml::encodeJsCall(
1243                                 'mw.loader.state',
1244                                 [ $name ],
1245                                 ResourceLoader::inDebugMode()
1246                         );
1247                 } else {
1248                         return Xml::encodeJsCall(
1249                                 'mw.loader.state',
1250                                 [ $name, $state ],
1251                                 ResourceLoader::inDebugMode()
1252                         );
1253                 }
1254         }
1255
1256         /**
1257          * Returns JS code which calls the script given by $script. The script will
1258          * be called with local variables name, version, dependencies and group,
1259          * which will have values corresponding to $name, $version, $dependencies
1260          * and $group as supplied.
1261          *
1262          * @param string $name Module name
1263          * @param string $version Module version hash
1264          * @param array $dependencies List of module names on which this module depends
1265          * @param string $group Group which the module is in.
1266          * @param string $source Source of the module, or 'local' if not foreign.
1267          * @param string $script JavaScript code
1268          * @return string
1269          */
1270         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1271                 $group, $source, $script
1272         ) {
1273                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1274                 return Xml::encodeJsCall(
1275                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1276                         [ $name, $version, $dependencies, $group, $source ],
1277                         ResourceLoader::inDebugMode()
1278                 );
1279         }
1280
1281         private static function isEmptyObject( stdClass $obj ) {
1282                 foreach ( $obj as $key => $value ) {
1283                         return false;
1284                 }
1285                 return true;
1286         }
1287
1288         /**
1289          * Remove empty values from the end of an array.
1290          *
1291          * Values considered empty:
1292          *
1293          * - null
1294          * - []
1295          * - new XmlJsCode( '{}' )
1296          * - new stdClass() // (object) []
1297          *
1298          * @param Array $array
1299          */
1300         private static function trimArray( array &$array ) {
1301                 $i = count( $array );
1302                 while ( $i-- ) {
1303                         if ( $array[$i] === null
1304                                 || $array[$i] === []
1305                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1306                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1307                         ) {
1308                                 unset( $array[$i] );
1309                         } else {
1310                                 break;
1311                         }
1312                 }
1313         }
1314
1315         /**
1316          * Returns JS code which calls mw.loader.register with the given
1317          * parameters. Has three calling conventions:
1318          *
1319          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1320          *        $dependencies, $group, $source, $skip
1321          *     ):
1322          *        Register a single module.
1323          *
1324          *   - ResourceLoader::makeLoaderRegisterScript( [ $name1, $name2 ] ):
1325          *        Register modules with the given names.
1326          *
1327          *   - ResourceLoader::makeLoaderRegisterScript( [
1328          *        [ $name1, $version1, $dependencies1, $group1, $source1, $skip1 ],
1329          *        [ $name2, $version2, $dependencies1, $group2, $source2, $skip2 ],
1330          *        ...
1331          *     ] ):
1332          *        Registers modules with the given names and parameters.
1333          *
1334          * @param string $name Module name
1335          * @param string $version Module version hash
1336          * @param array $dependencies List of module names on which this module depends
1337          * @param string $group Group which the module is in
1338          * @param string $source Source of the module, or 'local' if not foreign
1339          * @param string $skip Script body of the skip function
1340          * @return string
1341          */
1342         public static function makeLoaderRegisterScript( $name, $version = null,
1343                 $dependencies = null, $group = null, $source = null, $skip = null
1344         ) {
1345                 if ( is_array( $name ) ) {
1346                         // Build module name index
1347                         $index = [];
1348                         foreach ( $name as $i => &$module ) {
1349                                 $index[$module[0]] = $i;
1350                         }
1351
1352                         // Transform dependency names into indexes when possible, they will be resolved by
1353                         // mw.loader.register on the other end
1354                         foreach ( $name as &$module ) {
1355                                 if ( isset( $module[2] ) ) {
1356                                         foreach ( $module[2] as &$dependency ) {
1357                                                 if ( isset( $index[$dependency] ) ) {
1358                                                         $dependency = $index[$dependency];
1359                                                 }
1360                                         }
1361                                 }
1362                         }
1363
1364                         array_walk( $name, [ 'self', 'trimArray' ] );
1365
1366                         return Xml::encodeJsCall(
1367                                 'mw.loader.register',
1368                                 [ $name ],
1369                                 ResourceLoader::inDebugMode()
1370                         );
1371                 } else {
1372                         $registration = [ $name, $version, $dependencies, $group, $source, $skip ];
1373                         self::trimArray( $registration );
1374                         return Xml::encodeJsCall(
1375                                 'mw.loader.register',
1376                                 $registration,
1377                                 ResourceLoader::inDebugMode()
1378                         );
1379                 }
1380         }
1381
1382         /**
1383          * Returns JS code which calls mw.loader.addSource() with the given
1384          * parameters. Has two calling conventions:
1385          *
1386          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1387          *       Register a single source
1388          *
1389          *   - ResourceLoader::makeLoaderSourcesScript( [ $id1 => $loadUrl, $id2 => $loadUrl, ... ] );
1390          *       Register sources with the given IDs and properties.
1391          *
1392          * @param string $id Source ID
1393          * @param string $loadUrl load.php url
1394          * @return string
1395          */
1396         public static function makeLoaderSourcesScript( $id, $loadUrl = null ) {
1397                 if ( is_array( $id ) ) {
1398                         return Xml::encodeJsCall(
1399                                 'mw.loader.addSource',
1400                                 [ $id ],
1401                                 ResourceLoader::inDebugMode()
1402                         );
1403                 } else {
1404                         return Xml::encodeJsCall(
1405                                 'mw.loader.addSource',
1406                                 [ $id, $loadUrl ],
1407                                 ResourceLoader::inDebugMode()
1408                         );
1409                 }
1410         }
1411
1412         /**
1413          * Returns JS code which runs given JS code if the client-side framework is
1414          * present.
1415          *
1416          * @deprecated since 1.25; use makeInlineScript instead
1417          * @param string $script JavaScript code
1418          * @return string
1419          */
1420         public static function makeLoaderConditionalScript( $script ) {
1421                 return '(window.RLQ=window.RLQ||[]).push(function(){' .
1422                         trim( $script ) . '});';
1423         }
1424
1425         /**
1426          * Construct an inline script tag with given JS code.
1427          *
1428          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1429          * only if the client has adequate support for MediaWiki JavaScript code.
1430          *
1431          * @param string $script JavaScript code
1432          * @return WrappedString HTML
1433          */
1434         public static function makeInlineScript( $script ) {
1435                 $js = self::makeLoaderConditionalScript( $script );
1436                 return new WrappedString(
1437                         Html::inlineScript( $js ),
1438                         '<script>(window.RLQ=window.RLQ||[]).push(function(){',
1439                         '});</script>'
1440                 );
1441         }
1442
1443         /**
1444          * Returns JS code which will set the MediaWiki configuration array to
1445          * the given value.
1446          *
1447          * @param array $configuration List of configuration values keyed by variable name
1448          * @return string
1449          */
1450         public static function makeConfigSetScript( array $configuration ) {
1451                 return Xml::encodeJsCall(
1452                         'mw.config.set',
1453                         [ $configuration ],
1454                         ResourceLoader::inDebugMode()
1455                 );
1456         }
1457
1458         /**
1459          * Convert an array of module names to a packed query string.
1460          *
1461          * For example, [ 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' ]
1462          * becomes 'foo.bar,baz|bar.baz,quux'
1463          * @param array $modules List of module names (strings)
1464          * @return string Packed query string
1465          */
1466         public static function makePackedModulesString( $modules ) {
1467                 $groups = []; // [ prefix => [ suffixes ] ]
1468                 foreach ( $modules as $module ) {
1469                         $pos = strrpos( $module, '.' );
1470                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1471                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1472                         $groups[$prefix][] = $suffix;
1473                 }
1474
1475                 $arr = [];
1476                 foreach ( $groups as $prefix => $suffixes ) {
1477                         $p = $prefix === '' ? '' : $prefix . '.';
1478                         $arr[] = $p . implode( ',', $suffixes );
1479                 }
1480                 $str = implode( '|', $arr );
1481                 return $str;
1482         }
1483
1484         /**
1485          * Determine whether debug mode was requested
1486          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1487          * @return bool
1488          */
1489         public static function inDebugMode() {
1490                 if ( self::$debugMode === null ) {
1491                         global $wgRequest, $wgResourceLoaderDebug;
1492                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1493                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1494                         );
1495                 }
1496                 return self::$debugMode;
1497         }
1498
1499         /**
1500          * Reset static members used for caching.
1501          *
1502          * Global state and $wgRequest are evil, but we're using it right
1503          * now and sometimes we need to be able to force ResourceLoader to
1504          * re-evaluate the context because it has changed (e.g. in the test suite).
1505          */
1506         public static function clearCache() {
1507                 self::$debugMode = null;
1508         }
1509
1510         /**
1511          * Build a load.php URL
1512          *
1513          * @since 1.24
1514          * @param string $source Name of the ResourceLoader source
1515          * @param ResourceLoaderContext $context
1516          * @param array $extraQuery
1517          * @return string URL to load.php. May be protocol-relative if $wgLoadScript is, too.
1518          */
1519         public function createLoaderURL( $source, ResourceLoaderContext $context,
1520                 $extraQuery = []
1521         ) {
1522                 $query = self::createLoaderQuery( $context, $extraQuery );
1523                 $script = $this->getLoadScript( $source );
1524
1525                 return wfAppendQuery( $script, $query );
1526         }
1527
1528         /**
1529          * Helper for createLoaderURL()
1530          *
1531          * @since 1.24
1532          * @see makeLoaderQuery
1533          * @param ResourceLoaderContext $context
1534          * @param array $extraQuery
1535          * @return array
1536          */
1537         protected static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = [] ) {
1538                 return self::makeLoaderQuery(
1539                         $context->getModules(),
1540                         $context->getLanguage(),
1541                         $context->getSkin(),
1542                         $context->getUser(),
1543                         $context->getVersion(),
1544                         $context->getDebug(),
1545                         $context->getOnly(),
1546                         $context->getRequest()->getBool( 'printable' ),
1547                         $context->getRequest()->getBool( 'handheld' ),
1548                         $extraQuery
1549                 );
1550         }
1551
1552         /**
1553          * Build a query array (array representation of query string) for load.php. Helper
1554          * function for createLoaderURL().
1555          *
1556          * @param array $modules
1557          * @param string $lang
1558          * @param string $skin
1559          * @param string $user
1560          * @param string $version
1561          * @param bool $debug
1562          * @param string $only
1563          * @param bool $printable
1564          * @param bool $handheld
1565          * @param array $extraQuery
1566          *
1567          * @return array
1568          */
1569         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1570                 $version = null, $debug = false, $only = null, $printable = false,
1571                 $handheld = false, $extraQuery = []
1572         ) {
1573                 $query = [
1574                         'modules' => self::makePackedModulesString( $modules ),
1575                         'lang' => $lang,
1576                         'skin' => $skin,
1577                         'debug' => $debug ? 'true' : 'false',
1578                 ];
1579                 if ( $user !== null ) {
1580                         $query['user'] = $user;
1581                 }
1582                 if ( $version !== null ) {
1583                         $query['version'] = $version;
1584                 }
1585                 if ( $only !== null ) {
1586                         $query['only'] = $only;
1587                 }
1588                 if ( $printable ) {
1589                         $query['printable'] = 1;
1590                 }
1591                 if ( $handheld ) {
1592                         $query['handheld'] = 1;
1593                 }
1594                 $query += $extraQuery;
1595
1596                 // Make queries uniform in order
1597                 ksort( $query );
1598                 return $query;
1599         }
1600
1601         /**
1602          * Check a module name for validity.
1603          *
1604          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1605          * at most 255 bytes.
1606          *
1607          * @param string $moduleName Module name to check
1608          * @return bool Whether $moduleName is a valid module name
1609          */
1610         public static function isValidModuleName( $moduleName ) {
1611                 return strcspn( $moduleName, '!,|', 0, 255 ) === strlen( $moduleName );
1612         }
1613
1614         /**
1615          * Returns LESS compiler set up for use with MediaWiki
1616          *
1617          * @since 1.27
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 function getLessCompiler( $extraVars = [] ) {
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( $this->getLessVars(), $extraVars ) );
1633                 $parser->SetImportDirs(
1634                         array_fill_keys( $this->config->get( 'ResourceLoaderLESSImportPaths' ), '' )
1635                 );
1636                 $parser->SetOption( 'relativeUrls', false );
1637
1638                 return $parser;
1639         }
1640
1641         /**
1642          * Get global LESS variables.
1643          *
1644          * @since 1.27
1645          * @return array Map of variable names to string CSS values.
1646          */
1647         public function getLessVars() {
1648                 if ( !$this->lessVars ) {
1649                         $lessVars = $this->config->get( 'ResourceLoaderLESSVars' );
1650                         Hooks::run( 'ResourceLoaderGetLessVars', [ &$lessVars ] );
1651                         $this->lessVars = $lessVars;
1652                 }
1653                 return $this->lessVars;
1654         }
1655 }