includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /** @var array */
  39         private static $lessVars = null;
  40
  41         /**
  42          * Module name/ResourceLoaderModule object pairs
  43          * @var array
  44          */
  45         protected $modules = array();
  46
  47         /**
  48          * Associative array mapping module name to info associative array
  49          * @var array
  50          */
  51         protected $moduleInfos = array();
  52
  53         /** @var Config $config */
  54         private $config;
  55
  56         /**
  57          * Associative array mapping framework ids to a list of names of test suite modules
  58          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  59          * @var array
  60          */
  61         protected $testModuleNames = array();
  62
  63         /**
  64          * E.g. array( 'source-id' => 'http://.../load.php' )
  65          * @var array
  66          */
  67         protected $sources = array();
  68
  69         /**
  70          * Errors accumulated during current respond() call.
  71          * @var array
  72          */
  73         protected $errors = array();
  74
  75         /**
  76          * @var MessageBlobStore
  77          */
  78         protected $blobStore;
  79
  80         /**
  81          * Load information stored in the database about modules.
  82          *
  83          * This method grabs modules dependencies from the database and updates modules
  84          * objects.
  85          *
  86          * This is not inside the module code because it is much faster to
  87          * request all of the information at once than it is to have each module
  88          * requests its own information. This sacrifice of modularity yields a substantial
  89          * performance improvement.
  90          *
  91          * @param array $modules List of module names to preload information for
  92          * @param ResourceLoaderContext $context Context to load the information within
  93          */
  94         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  95                 if ( !count( $modules ) ) {
  96                         // Or else Database*::select() will explode, plus it's cheaper!
  97                         return;
  98                 }
  99                 $dbr = wfGetDB( DB_SLAVE );
 100                 $skin = $context->getSkin();
 101                 $lang = $context->getLanguage();
 102
 103                 // Get file dependency information
 104                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 105                                 'md_module' => $modules,
 106                                 'md_skin' => $skin
 107                         ), __METHOD__
 108                 );
 109
 110                 // Set modules' dependencies
 111                 $modulesWithDeps = array();
 112                 foreach ( $res as $row ) {
 113                         $module = $this->getModule( $row->md_module );
 114                         if ( $module ) {
 115                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 116                                 $modulesWithDeps[] = $row->md_module;
 117                         }
 118                 }
 119
 120                 // Register the absence of a dependency row too
 121                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 122                         $module = $this->getModule( $name );
 123                         if ( $module ) {
 124                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 125                         }
 126                 }
 127
 128                 // Get message blob mtimes. Only do this for modules with messages
 129                 $modulesWithMessages = array();
 130                 foreach ( $modules as $name ) {
 131                         $module = $this->getModule( $name );
 132                         if ( $module && count( $module->getMessages() ) ) {
 133                                 $modulesWithMessages[] = $name;
 134                         }
 135                 }
 136                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 137                 if ( count( $modulesWithMessages ) ) {
 138                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 139                                         'mr_resource' => $modulesWithMessages,
 140                                         'mr_lang' => $lang
 141                                 ), __METHOD__
 142                         );
 143                         foreach ( $res as $row ) {
 144                                 $module = $this->getModule( $row->mr_resource );
 145                                 if ( $module ) {
 146                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 147                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 148                                 }
 149                         }
 150                 }
 151                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 152                         $module = $this->getModule( $name );
 153                         if ( $module ) {
 154                                 $module->setMsgBlobMtime( $lang, 1 );
 155                         }
 156                 }
 157         }
 158
 159         /**
 160          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 161          *
 162          * Available filters are:
 163          *
 164          *    - minify-js \see JavaScriptMinifier::minify
 165          *    - minify-css \see CSSMin::minify
 166          *
 167          * If $data is empty, only contains whitespace or the filter was unknown,
 168          * $data is returned unmodified.
 169          *
 170          * @param string $filter Name of filter to run
 171          * @param string $data Text to filter, such as JavaScript or CSS text
 172          * @param string $cacheReport Whether to include the cache key report
 173          * @return string Filtered data, or a comment containing an error message
 174          */
 175         public function filter( $filter, $data, $cacheReport = true ) {
 176
 177                 // For empty/whitespace-only data or for unknown filters, don't perform
 178                 // any caching or processing
 179                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 180                         return $data;
 181                 }
 182
 183                 // Try for cache hit
 184                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 185                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 186                 $cache = wfGetCache( CACHE_ANYTHING );
 187                 $cacheEntry = $cache->get( $key );
 188                 if ( is_string( $cacheEntry ) ) {
 189                         wfIncrStats( "rl-$filter-cache-hits" );
 190                         return $cacheEntry;
 191                 }
 192
 193                 $result = '';
 194                 // Run the filter - we've already verified one of these will work
 195                 try {
 196                         wfIncrStats( "rl-$filter-cache-misses" );
 197                         switch ( $filter ) {
 198                                 case 'minify-js':
 199                                         $result = JavaScriptMinifier::minify( $data,
 200                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 201                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 202                                         );
 203                                         if ( $cacheReport ) {
 204                                                 $result .= "\n/* cache key: $key */";
 205                                         }
 206                                         break;
 207                                 case 'minify-css':
 208                                         $result = CSSMin::minify( $data );
 209                                         if ( $cacheReport ) {
 210                                                 $result .= "\n/* cache key: $key */";
 211                                         }
 212                                         break;
 213                         }
 214
 215                         // Save filtered text to Memcached
 216                         $cache->set( $key, $result );
 217                 } catch ( Exception $e ) {
 218                         MWExceptionHandler::logException( $e );
 219                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 220                         $this->errors[] = self::formatExceptionNoComment( $e );
 221                 }
 222
 223                 return $result;
 224         }
 225
 226         /* Methods */
 227
 228         /**
 229          * Register core modules and runs registration hooks.
 230          * @param Config|null $config
 231          */
 232         public function __construct( Config $config = null ) {
 233                 global $IP;
 234
 235                 if ( $config === null ) {
 236                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 237                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 238                 }
 239
 240                 $this->config = $config;
 241
 242                 // Add 'local' source first
 243                 $this->addSource( 'local', wfScript( 'load' ) );
 244
 245                 // Add other sources
 246                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 247
 248                 // Register core modules
 249                 $this->register( include "$IP/resources/Resources.php" );
 250                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 251                 // Register extension modules
 252                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 253                 $this->register( $config->get( 'ResourceModules' ) );
 254
 255                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 256                         $this->registerTestModules();
 257                 }
 258
 259                 $this->setMessageBlobStore( new MessageBlobStore() );
 260         }
 261
 262         /**
 263          * @return Config
 264          */
 265         public function getConfig() {
 266                 return $this->config;
 267         }
 268
 269         /**
 270          * @param MessageBlobStore $blobStore
 271          * @since 1.25
 272          */
 273         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 274                 $this->blobStore = $blobStore;
 275         }
 276
 277         /**
 278          * Register a module with the ResourceLoader system.
 279          *
 280          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 281          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 282          *   this may also be a ResourceLoaderModule object. Optional when using
 283          *   multiple-registration calling style.
 284          * @throws MWException If a duplicate module registration is attempted
 285          * @throws MWException If a module name contains illegal characters (pipes or commas)
 286          * @throws MWException If something other than a ResourceLoaderModule is being registered
 287          * @return bool False if there were any errors, in which case one or more modules were
 288          *   not registered
 289          */
 290         public function register( $name, $info = null ) {
 291
 292                 // Allow multiple modules to be registered in one call
 293                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 294                 foreach ( $registrations as $name => $info ) {
 295                         // Disallow duplicate registrations
 296                         if ( isset( $this->moduleInfos[$name] ) ) {
 297                                 // A module has already been registered by this name
 298                                 throw new MWException(
 299                                         'ResourceLoader duplicate registration error. ' .
 300                                         'Another module has already been registered as ' . $name
 301                                 );
 302                         }
 303
 304                         // Check $name for validity
 305                         if ( !self::isValidModuleName( $name ) ) {
 306                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 307                                         . "see ResourceLoader::isValidModuleName()" );
 308                         }
 309
 310                         // Attach module
 311                         if ( $info instanceof ResourceLoaderModule ) {
 312                                 $this->moduleInfos[$name] = array( 'object' => $info );
 313                                 $info->setName( $name );
 314                                 $this->modules[$name] = $info;
 315                         } elseif ( is_array( $info ) ) {
 316                                 // New calling convention
 317                                 $this->moduleInfos[$name] = $info;
 318                         } else {
 319                                 throw new MWException(
 320                                         'ResourceLoader module info type error for module \'' . $name .
 321                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 322                                 );
 323                         }
 324
 325                         // Last-minute changes
 326
 327                         // Apply custom skin-defined styles to existing modules.
 328                         if ( $this->isFileModule( $name ) ) {
 329                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 330                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 331                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 332                                                 continue;
 333                                         }
 334
 335                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 336                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 337                                         if ( isset( $skinStyles[$name] ) ) {
 338                                                 $paths = (array)$skinStyles[$name];
 339                                                 $styleFiles = array();
 340                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 341                                                 $paths = (array)$skinStyles['+' . $name];
 342                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 343                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 344                                                         array();
 345                                         } else {
 346                                                 continue;
 347                                         }
 348
 349                                         // Add new file paths, remapping them to refer to our directories and not use settings
 350                                         // from the module we're modifying, which come from the base definition.
 351                                         list( $localBasePath, $remoteBasePath ) =
 352                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 353
 354                                         foreach ( $paths as $path ) {
 355                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 356                                         }
 357
 358                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 359                                 }
 360                         }
 361                 }
 362
 363         }
 364
 365         /**
 366          */
 367         public function registerTestModules() {
 368                 global $IP;
 369
 370                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 371                         throw new MWException( 'Attempt to register JavaScript test modules '
 372                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 373                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 374                 }
 375
 376                 // Get core test suites
 377                 $testModules = array();
 378                 $testModules['qunit'] = array();
 379                 // Get other test suites (e.g. from extensions)
 380                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 381
 382                 // Add the testrunner (which configures QUnit) to the dependencies.
 383                 // Since it must be ready before any of the test suites are executed.
 384                 foreach ( $testModules['qunit'] as &$module ) {
 385                         // Make sure all test modules are top-loading so that when QUnit starts
 386                         // on document-ready, it will run once and finish. If some tests arrive
 387                         // later (possibly after QUnit has already finished) they will be ignored.
 388                         $module['position'] = 'top';
 389                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 390                 }
 391
 392                 $testModules['qunit'] =
 393                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 394
 395                 foreach ( $testModules as $id => $names ) {
 396                         // Register test modules
 397                         $this->register( $testModules[$id] );
 398
 399                         // Keep track of their names so that they can be loaded together
 400                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 401                 }
 402
 403         }
 404
 405         /**
 406          * Add a foreign source of modules.
 407          *
 408          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 409          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 410          *  backwards-compatibility.
 411          * @throws MWException
 412          */
 413         public function addSource( $id, $loadUrl = null ) {
 414                 // Allow multiple sources to be registered in one call
 415                 if ( is_array( $id ) ) {
 416                         foreach ( $id as $key => $value ) {
 417                                 $this->addSource( $key, $value );
 418                         }
 419                         return;
 420                 }
 421
 422                 // Disallow duplicates
 423                 if ( isset( $this->sources[$id] ) ) {
 424                         throw new MWException(
 425                                 'ResourceLoader duplicate source addition error. ' .
 426                                 'Another source has already been registered as ' . $id
 427                         );
 428                 }
 429
 430                 // Pre 1.24 backwards-compatibility
 431                 if ( is_array( $loadUrl ) ) {
 432                         if ( !isset( $loadUrl['loadScript'] ) ) {
 433                                 throw new MWException(
 434                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 435                                 );
 436                         }
 437
 438                         $loadUrl = $loadUrl['loadScript'];
 439                 }
 440
 441                 $this->sources[$id] = $loadUrl;
 442         }
 443
 444         /**
 445          * Get a list of module names.
 446          *
 447          * @return array List of module names
 448          */
 449         public function getModuleNames() {
 450                 return array_keys( $this->moduleInfos );
 451         }
 452
 453         /**
 454          * Get a list of test module names for one (or all) frameworks.
 455          *
 456          * If the given framework id is unknkown, or if the in-object variable is not an array,
 457          * then it will return an empty array.
 458          *
 459          * @param string $framework Get only the test module names for one
 460          *   particular framework (optional)
 461          * @return array
 462          */
 463         public function getTestModuleNames( $framework = 'all' ) {
 464                 /** @todo api siteinfo prop testmodulenames modulenames */
 465                 if ( $framework == 'all' ) {
 466                         return $this->testModuleNames;
 467                 } elseif ( isset( $this->testModuleNames[$framework] )
 468                         && is_array( $this->testModuleNames[$framework] )
 469                 ) {
 470                         return $this->testModuleNames[$framework];
 471                 } else {
 472                         return array();
 473                 }
 474         }
 475
 476         /**
 477          * Check whether a ResourceLoader module is registered
 478          *
 479          * @since 1.25
 480          * @param string $name
 481          * @return bool
 482          */
 483         public function isModuleRegistered( $name ) {
 484                 return isset( $this->moduleInfos[$name] );
 485         }
 486
 487         /**
 488          * Get the ResourceLoaderModule object for a given module name.
 489          *
 490          * If an array of module parameters exists but a ResourceLoaderModule object has not
 491          * yet been instantiated, this method will instantiate and cache that object such that
 492          * subsequent calls simply return the same object.
 493          *
 494          * @param string $name Module name
 495          * @return ResourceLoaderModule|null If module has been registered, return a
 496          *  ResourceLoaderModule instance. Otherwise, return null.
 497          */
 498         public function getModule( $name ) {
 499                 if ( !isset( $this->modules[$name] ) ) {
 500                         if ( !isset( $this->moduleInfos[$name] ) ) {
 501                                 // No such module
 502                                 return null;
 503                         }
 504                         // Construct the requested object
 505                         $info = $this->moduleInfos[$name];
 506                         /** @var ResourceLoaderModule $object */
 507                         if ( isset( $info['object'] ) ) {
 508                                 // Object given in info array
 509                                 $object = $info['object'];
 510                         } else {
 511                                 if ( !isset( $info['class'] ) ) {
 512                                         $class = 'ResourceLoaderFileModule';
 513                                 } else {
 514                                         $class = $info['class'];
 515                                 }
 516                                 /** @var ResourceLoaderModule $object */
 517                                 $object = new $class( $info );
 518                                 $object->setConfig( $this->getConfig() );
 519                         }
 520                         $object->setName( $name );
 521                         $this->modules[$name] = $object;
 522                 }
 523
 524                 return $this->modules[$name];
 525         }
 526
 527         /**
 528          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 529          *
 530          * @param string $name Module name
 531          * @return bool
 532          */
 533         protected function isFileModule( $name ) {
 534                 if ( !isset( $this->moduleInfos[$name] ) ) {
 535                         return false;
 536                 }
 537                 $info = $this->moduleInfos[$name];
 538                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 539                         return false;
 540                 }
 541                 return true;
 542         }
 543
 544         /**
 545          * Get the list of sources.
 546          *
 547          * @return array Like array( id => load.php url, .. )
 548          */
 549         public function getSources() {
 550                 return $this->sources;
 551         }
 552
 553         /**
 554          * Get the URL to the load.php endpoint for the given
 555          * ResourceLoader source
 556          *
 557          * @since 1.24
 558          * @param string $source
 559          * @throws MWException On an invalid $source name
 560          * @return string
 561          */
 562         public function getLoadScript( $source ) {
 563                 if ( !isset( $this->sources[$source] ) ) {
 564                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 565                 }
 566                 return $this->sources[$source];
 567         }
 568
 569         /**
 570          * @since 1.26
 571          * @param string $value
 572          * @return string Hash
 573          */
 574         public static function makeHash( $value ) {
 575                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 576                 // The first 8 chars of a base64 encoded digest represent the same binary as
 577                 // the first 12 chars of a hex encoded digest.
 578                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 579         }
 580
 581         /**
 582          * Helper method to get and combine versions of multiple modules.
 583          *
 584          * @since 1.26
 585          * @param ResourceLoaderContext $context
 586          * @param array $modules List of ResourceLoaderModule objects
 587          * @return string Hash
 588          */
 589         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 590                 if ( !$modules ) {
 591                         return '';
 592                 }
 593                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 594                 // http://php.net/functions.anonymous
 595                 $rl = $this;
 596                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 597                         return $rl->getModule( $module )->getVersionHash( $context );
 598                 }, $modules );
 599                 return self::makeHash( implode( $hashes ) );
 600         }
 601
 602         /**
 603          * Output a response to a load request, including the content-type header.
 604          *
 605          * @param ResourceLoaderContext $context Context in which a response should be formed
 606          */
 607         public function respond( ResourceLoaderContext $context ) {
 608                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 609                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 610                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 611                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 612                 // the whole thing in our own output buffer to be sure the active buffer
 613                 // doesn't use ob_gzhandler.
 614                 // See http://bugs.php.net/bug.php?id=36514
 615                 ob_start();
 616
 617                 // Find out which modules are missing and instantiate the others
 618                 $modules = array();
 619                 $missing = array();
 620                 foreach ( $context->getModules() as $name ) {
 621                         $module = $this->getModule( $name );
 622                         if ( $module ) {
 623                                 // Do not allow private modules to be loaded from the web.
 624                                 // This is a security issue, see bug 34907.
 625                                 if ( $module->getGroup() === 'private' ) {
 626                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 627                                         $this->errors[] = "Cannot show private module \"$name\"";
 628                                         continue;
 629                                 }
 630                                 $modules[$name] = $module;
 631                         } else {
 632                                 $missing[] = $name;
 633                         }
 634                 }
 635
 636                 try {
 637                         // Preload for getCombinedVersion()
 638                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 639                 } catch ( Exception $e ) {
 640                         MWExceptionHandler::logException( $e );
 641                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 642                         $this->errors[] = self::formatExceptionNoComment( $e );
 643                 }
 644
 645                 // Combine versions to propagate cache invalidation
 646                 $versionHash = '';
 647                 try {
 648                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 649                 } catch ( Exception $e ) {
 650                         MWExceptionHandler::logException( $e );
 651                         wfDebugLog( 'resourceloader', __METHOD__ . ": calculating version hash failed: $e" );
 652                         $this->errors[] = self::formatExceptionNoComment( $e );
 653                 }
 654
 655                 // See RFC 2616 § 3.11 Entity Tags
 656                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 657                 $etag = 'W/"' . $versionHash . '"';
 658
 659                 // Try the client-side cache first
 660                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 661                         return; // output handled (buffers cleared)
 662                 }
 663
 664                 // Use file cache if enabled and available...
 665                 if ( $this->config->get( 'UseFileCache' ) ) {
 666                         $fileCache = ResourceFileCache::newFromContext( $context );
 667                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 668                                 return; // output handled
 669                         }
 670                 }
 671
 672                 // Generate a response
 673                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 674
 675                 // Capture any PHP warnings from the output buffer and append them to the
 676                 // error list if we're in debug mode.
 677                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 678                         $this->errors[] = $warnings;
 679                 }
 680
 681                 // Save response to file cache unless there are errors
 682                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 683                         // Cache single modules and images...and other requests if there are enough hits
 684                         if ( ResourceFileCache::useFileCache( $context ) ) {
 685                                 if ( $fileCache->isCacheWorthy() ) {
 686                                         $fileCache->saveText( $response );
 687                                 } else {
 688                                         $fileCache->incrMissesRecent( $context->getRequest() );
 689                                 }
 690                         }
 691                 }
 692
 693                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 694
 695                 // Remove the output buffer and output the response
 696                 ob_end_clean();
 697
 698                 if ( $context->getImageObj() && $this->errors ) {
 699                         // We can't show both the error messages and the response when it's an image.
 700                         $errorText = '';
 701                         foreach ( $this->errors as $error ) {
 702                                 $errorText .= $error . "\n";
 703                         }
 704                         $response = $errorText;
 705                 } elseif ( $this->errors ) {
 706                         // Prepend comments indicating errors
 707                         $errorText = '';
 708                         foreach ( $this->errors as $error ) {
 709                                 $errorText .= self::makeComment( $error );
 710                         }
 711                         $response = $errorText . $response;
 712                 }
 713
 714                 $this->errors = array();
 715                 echo $response;
 716
 717         }
 718
 719         /**
 720          * Send main response headers to the client.
 721          *
 722          * Deals with Content-Type, CORS (for stylesheets), and caching.
 723          *
 724          * @param ResourceLoaderContext $context
 725          * @param string $etag ETag header value
 726          * @param bool $errors Whether there are errors in the response
 727          * @return void
 728          */
 729         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 730                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 731                 // If a version wasn't specified we need a shorter expiry time for updates
 732                 // to propagate to clients quickly
 733                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 734                 if ( is_null( $context->getVersion() ) || $errors ) {
 735                         $maxage = $rlMaxage['unversioned']['client'];
 736                         $smaxage = $rlMaxage['unversioned']['server'];
 737                 // If a version was specified we can use a longer expiry time since changing
 738                 // version numbers causes cache misses
 739                 } else {
 740                         $maxage = $rlMaxage['versioned']['client'];
 741                         $smaxage = $rlMaxage['versioned']['server'];
 742                 }
 743                 if ( $context->getImageObj() ) {
 744                         // Output different headers if we're outputting textual errors.
 745                         if ( $errors ) {
 746                                 header( 'Content-Type: text/plain; charset=utf-8' );
 747                         } else {
 748                                 $context->getImageObj()->sendResponseHeaders( $context );
 749                         }
 750                 } elseif ( $context->getOnly() === 'styles' ) {
 751                         header( 'Content-Type: text/css; charset=utf-8' );
 752                         header( 'Access-Control-Allow-Origin: *' );
 753                 } else {
 754                         header( 'Content-Type: text/javascript; charset=utf-8' );
 755                 }
 756                 // See RFC 2616 § 14.19 ETag
 757                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 758                 header( 'ETag: ' . $etag );
 759                 if ( $context->getDebug() ) {
 760                         // Do not cache debug responses
 761                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 762                         header( 'Pragma: no-cache' );
 763                 } else {
 764                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 765                         $exp = min( $maxage, $smaxage );
 766                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 767                 }
 768         }
 769
 770         /**
 771          * Respond with HTTP 304 Not Modified if appropiate.
 772          *
 773          * If there's an If-None-Match header, respond with a 304 appropriately
 774          * and clear out the output buffer. If the client cache is too old then do nothing.
 775          *
 776          * @param ResourceLoaderContext $context
 777          * @param string $etag ETag header value
 778          * @return bool True if HTTP 304 was sent and output handled
 779          */
 780         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 781                 // See RFC 2616 § 14.26 If-None-Match
 782                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 783                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 784                 // Never send 304s in debug mode
 785                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 786                         // There's another bug in ob_gzhandler (see also the comment at
 787                         // the top of this function) that causes it to gzip even empty
 788                         // responses, meaning it's impossible to produce a truly empty
 789                         // response (because the gzip header is always there). This is
 790                         // a problem because 304 responses have to be completely empty
 791                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 792                         // See also http://bugs.php.net/bug.php?id=51579
 793                         // To work around this, we tear down all output buffering before
 794                         // sending the 304.
 795                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 796
 797                         header( 'HTTP/1.0 304 Not Modified' );
 798                         header( 'Status: 304 Not Modified' );
 799
 800                         $this->sendResponseHeaders( $context, $etag, false );
 801                         return true;
 802                 }
 803                 return false;
 804         }
 805
 806         /**
 807          * Send out code for a response from file cache if possible.
 808          *
 809          * @param ResourceFileCache $fileCache Cache object for this request URL
 810          * @param ResourceLoaderContext $context Context in which to generate a response
 811          * @param string $etag ETag header value
 812          * @return bool If this found a cache file and handled the response
 813          */
 814         protected function tryRespondFromFileCache(
 815                 ResourceFileCache $fileCache,
 816                 ResourceLoaderContext $context,
 817                 $etag
 818         ) {
 819                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 820                 // Buffer output to catch warnings.
 821                 ob_start();
 822                 // Get the maximum age the cache can be
 823                 $maxage = is_null( $context->getVersion() )
 824                         ? $rlMaxage['unversioned']['server']
 825                         : $rlMaxage['versioned']['server'];
 826                 // Minimum timestamp the cache file must have
 827                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 828                 if ( !$good ) {
 829                         try { // RL always hits the DB on file cache miss...
 830                                 wfGetDB( DB_SLAVE );
 831                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 832                                 $good = $fileCache->isCacheGood(); // cache existence check
 833                         }
 834                 }
 835                 if ( $good ) {
 836                         $ts = $fileCache->cacheTimestamp();
 837                         // Send content type and cache headers
 838                         $this->sendResponseHeaders( $context, $etag, false );
 839                         $response = $fileCache->fetchText();
 840                         // Capture any PHP warnings from the output buffer and append them to the
 841                         // response in a comment if we're in debug mode.
 842                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 843                                 $response = self::makeComment( $warnings ) . $response;
 844                         }
 845                         // Remove the output buffer and output the response
 846                         ob_end_clean();
 847                         echo $response . "\n/* Cached {$ts} */";
 848                         return true; // cache hit
 849                 }
 850                 // Clear buffer
 851                 ob_end_clean();
 852
 853                 return false; // cache miss
 854         }
 855
 856         /**
 857          * Generate a CSS or JS comment block.
 858          *
 859          * Only use this for public data, not error message details.
 860          *
 861          * @param string $text
 862          * @return string
 863          */
 864         public static function makeComment( $text ) {
 865                 $encText = str_replace( '*/', '* /', $text );
 866                 return "/*\n$encText\n*/\n";
 867         }
 868
 869         /**
 870          * Handle exception display.
 871          *
 872          * @param Exception $e Exception to be shown to the user
 873          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 874          */
 875         public static function formatException( $e ) {
 876                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 877         }
 878
 879         /**
 880          * Handle exception display.
 881          *
 882          * @since 1.25
 883          * @param Exception $e Exception to be shown to the user
 884          * @return string Sanitized text that can be returned to the user
 885          */
 886         protected static function formatExceptionNoComment( $e ) {
 887                 global $wgShowExceptionDetails;
 888
 889                 if ( $wgShowExceptionDetails ) {
 890                         return $e->__toString();
 891                 } else {
 892                         return wfMessage( 'internalerror' )->text();
 893                 }
 894         }
 895
 896         /**
 897          * Generate code for a response.
 898          *
 899          * @param ResourceLoaderContext $context Context in which to generate a response
 900          * @param array $modules List of module objects keyed by module name
 901          * @param array $missing List of requested module names that are unregistered (optional)
 902          * @return string Response data
 903          */
 904         public function makeModuleResponse( ResourceLoaderContext $context,
 905                 array $modules, array $missing = array()
 906         ) {
 907                 $out = '';
 908                 $states = array();
 909
 910                 if ( !count( $modules ) && !count( $missing ) ) {
 911                         return <<<MESSAGE
 912 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 913    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 914    no modules were requested. Max made me put this here. */
 915 MESSAGE;
 916                 }
 917
 918                 $image = $context->getImageObj();
 919                 if ( $image ) {
 920                         $data = $image->getImageData( $context );
 921                         if ( $data === false ) {
 922                                 $data = '';
 923                                 $this->errors[] = 'Image generation failed';
 924                         }
 925                         return $data;
 926                 }
 927
 928                 // Pre-fetch blobs
 929                 if ( $context->shouldIncludeMessages() ) {
 930                         try {
 931                                 $blobs = $this->blobStore->get( $this, $modules, $context->getLanguage() );
 932                         } catch ( Exception $e ) {
 933                                 MWExceptionHandler::logException( $e );
 934                                 wfDebugLog(
 935                                         'resourceloader',
 936                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 937                                 );
 938                                 $this->errors[] = self::formatExceptionNoComment( $e );
 939                         }
 940                 } else {
 941                         $blobs = array();
 942                 }
 943
 944                 foreach ( $missing as $name ) {
 945                         $states[$name] = 'missing';
 946                 }
 947
 948                 // Generate output
 949                 $isRaw = false;
 950                 foreach ( $modules as $name => $module ) {
 951                         /**
 952                          * @var $module ResourceLoaderModule
 953                          */
 954
 955                         try {
 956                                 $scripts = '';
 957                                 if ( $context->shouldIncludeScripts() ) {
 958                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 959                                         // However, we can't do this if the module doesn't support it
 960                                         // We also can't do this if there is an only= parameter, because we have to give
 961                                         // the module a way to return a load.php URL without causing an infinite loop
 962                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 963                                                 $scripts = $module->getScriptURLsForDebug( $context );
 964                                         } else {
 965                                                 $scripts = $module->getScript( $context );
 966                                                 // rtrim() because there are usually a few line breaks
 967                                                 // after the last ';'. A new line at EOF, a new line
 968                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 969                                                 if ( is_string( $scripts )
 970                                                         && strlen( $scripts )
 971                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 972                                                 ) {
 973                                                         // Append semicolon to prevent weird bugs caused by files not
 974                                                         // terminating their statements right (bug 27054)
 975                                                         $scripts .= ";\n";
 976                                                 }
 977                                         }
 978                                 }
 979                                 // Styles
 980                                 $styles = array();
 981                                 if ( $context->shouldIncludeStyles() ) {
 982                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 983                                         // that don't *have* any stylesheets (bug 38024).
 984                                         $stylePairs = $module->getStyles( $context );
 985                                         if ( count( $stylePairs ) ) {
 986                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 987                                                 // See comment near shouldIncludeScripts() for more details
 988                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 989                                                         $styles = array(
 990                                                                 'url' => $module->getStyleURLsForDebug( $context )
 991                                                         );
 992                                                 } else {
 993                                                         // Minify CSS before embedding in mw.loader.implement call
 994                                                         // (unless in debug mode)
 995                                                         if ( !$context->getDebug() ) {
 996                                                                 foreach ( $stylePairs as $media => $style ) {
 997                                                                         // Can be either a string or an array of strings.
 998                                                                         if ( is_array( $style ) ) {
 999                                                                                 $stylePairs[$media] = array();
1000                                                                                 foreach ( $style as $cssText ) {
1001                                                                                         if ( is_string( $cssText ) ) {
1002                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
1003                                                                                         }
1004                                                                                 }
1005                                                                         } elseif ( is_string( $style ) ) {
1006                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
1007                                                                         }
1008                                                                 }
1009                                                         }
1010                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
1011                                                         $styles = array(
1012                                                                 'css' => self::makeCombinedStyles( $stylePairs )
1013                                                         );
1014                                                 }
1015                                         }
1016                                 }
1017
1018                                 // Messages
1019                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
1020
1021                                 // Append output
1022                                 switch ( $context->getOnly() ) {
1023                                         case 'scripts':
1024                                                 if ( is_string( $scripts ) ) {
1025                                                         // Load scripts raw...
1026                                                         $out .= $scripts;
1027                                                 } elseif ( is_array( $scripts ) ) {
1028                                                         // ...except when $scripts is an array of URLs
1029                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
1030                                                 }
1031                                                 break;
1032                                         case 'styles':
1033                                                 // We no longer seperate into media, they are all combined now with
1034                                                 // custom media type groups into @media .. {} sections as part of the css string.
1035                                                 // Module returns either an empty array or a numerical array with css strings.
1036                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1037                                                 break;
1038                                         default:
1039                                                 $out .= self::makeLoaderImplementScript(
1040                                                         $name,
1041                                                         $scripts,
1042                                                         $styles,
1043                                                         new XmlJsCode( $messagesBlob ),
1044                                                         $module->getTemplates()
1045                                                 );
1046                                                 break;
1047                                 }
1048                         } catch ( Exception $e ) {
1049                                 MWExceptionHandler::logException( $e );
1050                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1051                                 $this->errors[] = self::formatExceptionNoComment( $e );
1052
1053                                 // Respond to client with error-state instead of module implementation
1054                                 $states[$name] = 'error';
1055                                 unset( $modules[$name] );
1056                         }
1057                         $isRaw |= $module->isRaw();
1058                 }
1059
1060                 // Update module states
1061                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1062                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1063                                 // Set the state of modules loaded as only scripts to ready as
1064                                 // they don't have an mw.loader.implement wrapper that sets the state
1065                                 foreach ( $modules as $name => $module ) {
1066                                         $states[$name] = 'ready';
1067                                 }
1068                         }
1069
1070                         // Set the state of modules we didn't respond to with mw.loader.implement
1071                         if ( count( $states ) ) {
1072                                 $out .= self::makeLoaderStateScript( $states );
1073                         }
1074                 } else {
1075                         if ( count( $states ) ) {
1076                                 $this->errors[] = 'Problematic modules: ' .
1077                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1078                         }
1079                 }
1080
1081                 if ( !$context->getDebug() ) {
1082                         if ( $context->getOnly() === 'styles' ) {
1083                                 $out = $this->filter( 'minify-css', $out );
1084                         } else {
1085                                 $out = $this->filter( 'minify-js', $out );
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                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1114                 } elseif ( !is_array( $scripts ) ) {
1115                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1116                 }
1117                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1118                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1119                 // of "{}". Force them to objects.
1120                 $module = array(
1121                         $name,
1122                         $scripts,
1123                         (object) $styles,
1124                         (object) $messages,
1125                         (object) $templates,
1126                 );
1127                 self::trimArray( $module );
1128
1129                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1130         }
1131
1132         /**
1133          * Returns JS code which, when called, will register a given list of messages.
1134          *
1135          * @param mixed $messages Either an associative array mapping message key to value, or a
1136          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1137          * @return string
1138          */
1139         public static function makeMessageSetScript( $messages ) {
1140                 return Xml::encodeJsCall(
1141                         'mw.messages.set',
1142                         array( (object)$messages ),
1143                         ResourceLoader::inDebugMode()
1144                 );
1145         }
1146
1147         /**
1148          * Combines an associative array mapping media type to CSS into a
1149          * single stylesheet with "@media" blocks.
1150          *
1151          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1152          * @return array
1153          */
1154         public static function makeCombinedStyles( array $stylePairs ) {
1155                 $out = array();
1156                 foreach ( $stylePairs as $media => $styles ) {
1157                         // ResourceLoaderFileModule::getStyle can return the styles
1158                         // as a string or an array of strings. This is to allow separation in
1159                         // the front-end.
1160                         $styles = (array)$styles;
1161                         foreach ( $styles as $style ) {
1162                                 $style = trim( $style );
1163                                 // Don't output an empty "@media print { }" block (bug 40498)
1164                                 if ( $style !== '' ) {
1165                                         // Transform the media type based on request params and config
1166                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1167                                         $media = OutputPage::transformCssMedia( $media );
1168
1169                                         if ( $media === '' || $media == 'all' ) {
1170                                                 $out[] = $style;
1171                                         } elseif ( is_string( $media ) ) {
1172                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1173                                         }
1174                                         // else: skip
1175                                 }
1176                         }
1177                 }
1178                 return $out;
1179         }
1180
1181         /**
1182          * Returns a JS call to mw.loader.state, which sets the state of a
1183          * module or modules to a given value. Has two calling conventions:
1184          *
1185          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1186          *         Set the state of a single module called $name to $state
1187          *
1188          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1189          *         Set the state of modules with the given names to the given states
1190          *
1191          * @param string $name
1192          * @param string $state
1193          * @return string
1194          */
1195         public static function makeLoaderStateScript( $name, $state = null ) {
1196                 if ( is_array( $name ) ) {
1197                         return Xml::encodeJsCall(
1198                                 'mw.loader.state',
1199                                 array( $name ),
1200                                 ResourceLoader::inDebugMode()
1201                         );
1202                 } else {
1203                         return Xml::encodeJsCall(
1204                                 'mw.loader.state',
1205                                 array( $name, $state ),
1206                                 ResourceLoader::inDebugMode()
1207                         );
1208                 }
1209         }
1210
1211         /**
1212          * Returns JS code which calls the script given by $script. The script will
1213          * be called with local variables name, version, dependencies and group,
1214          * which will have values corresponding to $name, $version, $dependencies
1215          * and $group as supplied.
1216          *
1217          * @param string $name Module name
1218          * @param string $version Module version hash
1219          * @param array $dependencies List of module names on which this module depends
1220          * @param string $group Group which the module is in.
1221          * @param string $source Source of the module, or 'local' if not foreign.
1222          * @param string $script JavaScript code
1223          * @return string
1224          */
1225         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1226                 $group, $source, $script
1227         ) {
1228                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1229                 return Xml::encodeJsCall(
1230                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1231                         array( $name, $version, $dependencies, $group, $source ),
1232                         ResourceLoader::inDebugMode()
1233                 );
1234         }
1235
1236         private static function isEmptyObject( stdClass $obj ) {
1237                 foreach ( $obj as $key => &$value ) {
1238                         return false;
1239                 }
1240                 return true;
1241         }
1242
1243         /**
1244          * Remove empty values from the end of an array.
1245          *
1246          * Values considered empty:
1247          *
1248          * - null
1249          * - array()
1250          * - new XmlJsCode( '{}' )
1251          * - new stdClass() // (object) array()
1252          *
1253          * @param Array $array
1254          */
1255         private static function trimArray( Array &$array ) {
1256                 $i = count( $array );
1257                 while ( $i-- ) {
1258                         if ( $array[$i] === null
1259                                 || $array[$i] === array()
1260                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1261                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1262                         ) {
1263                                 unset( $array[$i] );
1264                         } else {
1265                                 break;
1266                         }
1267                 }
1268         }
1269
1270         /**
1271          * Returns JS code which calls mw.loader.register with the given
1272          * parameters. Has three calling conventions:
1273          *
1274          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1275          *        $dependencies, $group, $source, $skip
1276          *     ):
1277          *        Register a single module.
1278          *
1279          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1280          *        Register modules with the given names.
1281          *
1282          *   - ResourceLoader::makeLoaderRegisterScript( array(
1283          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1284          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1285          *        ...
1286          *     ) ):
1287          *        Registers modules with the given names and parameters.
1288          *
1289          * @param string $name Module name
1290          * @param string $version Module version hash
1291          * @param array $dependencies List of module names on which this module depends
1292          * @param string $group Group which the module is in
1293          * @param string $source Source of the module, or 'local' if not foreign
1294          * @param string $skip Script body of the skip function
1295          * @return string
1296          */
1297         public static function makeLoaderRegisterScript( $name, $version = null,
1298                 $dependencies = null, $group = null, $source = null, $skip = null
1299         ) {
1300                 if ( is_array( $name ) ) {
1301                         // Build module name index
1302                         $index = array();
1303                         foreach ( $name as $i => &$module ) {
1304                                 $index[$module[0]] = $i;
1305                         }
1306
1307                         // Transform dependency names into indexes when possible, they will be resolved by
1308                         // mw.loader.register on the other end
1309                         foreach ( $name as &$module ) {
1310                                 if ( isset( $module[2] ) ) {
1311                                         foreach ( $module[2] as &$dependency ) {
1312                                                 if ( isset( $index[$dependency] ) ) {
1313                                                         $dependency = $index[$dependency];
1314                                                 }
1315                                         }
1316                                 }
1317                         }
1318
1319                         array_walk( $name, array( 'self', 'trimArray' ) );
1320
1321                         return Xml::encodeJsCall(
1322                                 'mw.loader.register',
1323                                 array( $name ),
1324                                 ResourceLoader::inDebugMode()
1325                         );
1326                 } else {
1327                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1328                         self::trimArray( $registration );
1329                         return Xml::encodeJsCall(
1330                                 'mw.loader.register',
1331                                 $registration,
1332                                 ResourceLoader::inDebugMode()
1333                         );
1334                 }
1335         }
1336
1337         /**
1338          * Returns JS code which calls mw.loader.addSource() with the given
1339          * parameters. Has two calling conventions:
1340          *
1341          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1342          *       Register a single source
1343          *
1344          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1345          *       Register sources with the given IDs and properties.
1346          *
1347          * @param string $id Source ID
1348          * @param array $properties Source properties (see addSource())
1349          * @return string
1350          */
1351         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1352                 if ( is_array( $id ) ) {
1353                         return Xml::encodeJsCall(
1354                                 'mw.loader.addSource',
1355                                 array( $id ),
1356                                 ResourceLoader::inDebugMode()
1357                         );
1358                 } else {
1359                         return Xml::encodeJsCall(
1360                                 'mw.loader.addSource',
1361                                 array( $id, $properties ),
1362                                 ResourceLoader::inDebugMode()
1363                         );
1364                 }
1365         }
1366
1367         /**
1368          * Returns JS code which runs given JS code if the client-side framework is
1369          * present.
1370          *
1371          * @deprecated since 1.25; use makeInlineScript instead
1372          * @param string $script JavaScript code
1373          * @return string
1374          */
1375         public static function makeLoaderConditionalScript( $script ) {
1376                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1377         }
1378
1379         /**
1380          * Construct an inline script tag with given JS code.
1381          *
1382          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1383          * only if the client has adequate support for MediaWiki JavaScript code.
1384          *
1385          * @param string $script JavaScript code
1386          * @return string HTML
1387          */
1388         public static function makeInlineScript( $script ) {
1389                 $js = self::makeLoaderConditionalScript( $script );
1390                 return Html::inlineScript( $js );
1391         }
1392
1393         /**
1394          * Returns JS code which will set the MediaWiki configuration array to
1395          * the given value.
1396          *
1397          * @param array $configuration List of configuration values keyed by variable name
1398          * @return string
1399          */
1400         public static function makeConfigSetScript( array $configuration ) {
1401                 return Xml::encodeJsCall(
1402                         'mw.config.set',
1403                         array( $configuration ),
1404                         ResourceLoader::inDebugMode()
1405                 );
1406         }
1407
1408         /**
1409          * Convert an array of module names to a packed query string.
1410          *
1411          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1412          * becomes 'foo.bar,baz|bar.baz,quux'
1413          * @param array $modules List of module names (strings)
1414          * @return string Packed query string
1415          */
1416         public static function makePackedModulesString( $modules ) {
1417                 $groups = array(); // array( prefix => array( suffixes ) )
1418                 foreach ( $modules as $module ) {
1419                         $pos = strrpos( $module, '.' );
1420                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1421                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1422                         $groups[$prefix][] = $suffix;
1423                 }
1424
1425                 $arr = array();
1426                 foreach ( $groups as $prefix => $suffixes ) {
1427                         $p = $prefix === '' ? '' : $prefix . '.';
1428                         $arr[] = $p . implode( ',', $suffixes );
1429                 }
1430                 $str = implode( '|', $arr );
1431                 return $str;
1432         }
1433
1434         /**
1435          * Determine whether debug mode was requested
1436          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1437          * @return bool
1438          */
1439         public static function inDebugMode() {
1440                 if ( self::$debugMode === null ) {
1441                         global $wgRequest, $wgResourceLoaderDebug;
1442                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1443                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1444                         );
1445                 }
1446                 return self::$debugMode;
1447         }
1448
1449         /**
1450          * Reset static members used for caching.
1451          *
1452          * Global state and $wgRequest are evil, but we're using it right
1453          * now and sometimes we need to be able to force ResourceLoader to
1454          * re-evaluate the context because it has changed (e.g. in the test suite).
1455          */
1456         public static function clearCache() {
1457                 self::$debugMode = null;
1458         }
1459
1460         /**
1461          * Build a load.php URL
1462          *
1463          * @since 1.24
1464          * @param string $source Name of the ResourceLoader source
1465          * @param ResourceLoaderContext $context
1466          * @param array $extraQuery
1467          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1468          */
1469         public function createLoaderURL( $source, ResourceLoaderContext $context,
1470                 $extraQuery = array()
1471         ) {
1472                 $query = self::createLoaderQuery( $context, $extraQuery );
1473                 $script = $this->getLoadScript( $source );
1474
1475                 // Prevent the IE6 extension check from being triggered (bug 28840)
1476                 // by appending a character that's invalid in Windows extensions ('*')
1477                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1478         }
1479
1480         /**
1481          * Build a load.php URL
1482          * @deprecated since 1.24 Use createLoaderURL() instead
1483          * @param array $modules Array of module names (strings)
1484          * @param string $lang Language code
1485          * @param string $skin Skin name
1486          * @param string|null $user User name. If null, the &user= parameter is omitted
1487          * @param string|null $version Versioning timestamp
1488          * @param bool $debug Whether the request should be in debug mode
1489          * @param string|null $only &only= parameter
1490          * @param bool $printable Printable mode
1491          * @param bool $handheld Handheld mode
1492          * @param array $extraQuery Extra query parameters to add
1493          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1494          */
1495         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1496                 $version = null, $debug = false, $only = null, $printable = false,
1497                 $handheld = false, $extraQuery = array()
1498         ) {
1499                 global $wgLoadScript;
1500
1501                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1502                         $only, $printable, $handheld, $extraQuery
1503                 );
1504
1505                 // Prevent the IE6 extension check from being triggered (bug 28840)
1506                 // by appending a character that's invalid in Windows extensions ('*')
1507                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1508         }
1509
1510         /**
1511          * Helper for createLoaderURL()
1512          *
1513          * @since 1.24
1514          * @see makeLoaderQuery
1515          * @param ResourceLoaderContext $context
1516          * @param array $extraQuery
1517          * @return array
1518          */
1519         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1520                 return self::makeLoaderQuery(
1521                         $context->getModules(),
1522                         $context->getLanguage(),
1523                         $context->getSkin(),
1524                         $context->getUser(),
1525                         $context->getVersion(),
1526                         $context->getDebug(),
1527                         $context->getOnly(),
1528                         $context->getRequest()->getBool( 'printable' ),
1529                         $context->getRequest()->getBool( 'handheld' ),
1530                         $extraQuery
1531                 );
1532         }
1533
1534         /**
1535          * Build a query array (array representation of query string) for load.php. Helper
1536          * function for makeLoaderURL().
1537          *
1538          * @param array $modules
1539          * @param string $lang
1540          * @param string $skin
1541          * @param string $user
1542          * @param string $version
1543          * @param bool $debug
1544          * @param string $only
1545          * @param bool $printable
1546          * @param bool $handheld
1547          * @param array $extraQuery
1548          *
1549          * @return array
1550          */
1551         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1552                 $version = null, $debug = false, $only = null, $printable = false,
1553                 $handheld = false, $extraQuery = array()
1554         ) {
1555                 $query = array(
1556                         'modules' => self::makePackedModulesString( $modules ),
1557                         'lang' => $lang,
1558                         'skin' => $skin,
1559                         'debug' => $debug ? 'true' : 'false',
1560                 );
1561                 if ( $user !== null ) {
1562                         $query['user'] = $user;
1563                 }
1564                 if ( $version !== null ) {
1565                         $query['version'] = $version;
1566                 }
1567                 if ( $only !== null ) {
1568                         $query['only'] = $only;
1569                 }
1570                 if ( $printable ) {
1571                         $query['printable'] = 1;
1572                 }
1573                 if ( $handheld ) {
1574                         $query['handheld'] = 1;
1575                 }
1576                 $query += $extraQuery;
1577
1578                 // Make queries uniform in order
1579                 ksort( $query );
1580                 return $query;
1581         }
1582
1583         /**
1584          * Check a module name for validity.
1585          *
1586          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1587          * at most 255 bytes.
1588          *
1589          * @param string $moduleName Module name to check
1590          * @return bool Whether $moduleName is a valid module name
1591          */
1592         public static function isValidModuleName( $moduleName ) {
1593                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1594         }
1595
1596         /**
1597          * Returns LESS compiler set up for use with MediaWiki
1598          *
1599          * @param Config $config
1600          * @throws MWException
1601          * @since 1.22
1602          * @return lessc
1603          */
1604         public static function getLessCompiler( Config $config ) {
1605                 // When called from the installer, it is possible that a required PHP extension
1606                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1607                 // exception (caught by the installer) to prevent a fatal error later on.
1608                 if ( !class_exists( 'lessc' ) ) {
1609                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1610                 }
1611                 if ( !function_exists( 'ctype_digit' ) ) {
1612                         throw new MWException( 'lessc requires the Ctype extension' );
1613                 }
1614
1615                 $less = new lessc();
1616                 $less->setPreserveComments( true );
1617                 $less->setVariables( self::getLessVars( $config ) );
1618                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1619                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1620                         $less->registerFunction( $name, $func );
1621                 }
1622                 return $less;
1623         }
1624
1625         /**
1626          * Get global LESS variables.
1627          *
1628          * @param Config $config
1629          * @since 1.22
1630          * @return array Map of variable names to string CSS values.
1631          */
1632         public static function getLessVars( Config $config ) {
1633                 if ( !self::$lessVars ) {
1634                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1635                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1636                         // Sort by key to ensure consistent hashing for cache lookups.
1637                         ksort( $lessVars );
1638                         self::$lessVars = $lessVars;
1639                 }
1640                 return self::$lessVars;
1641         }
1642 }