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          * Load information stored in the database about modules.
  77          *
  78          * This method grabs modules dependencies from the database and updates modules
  79          * objects.
  80          *
  81          * This is not inside the module code because it is much faster to
  82          * request all of the information at once than it is to have each module
  83          * requests its own information. This sacrifice of modularity yields a substantial
  84          * performance improvement.
  85          *
  86          * @param array $modules List of module names to preload information for
  87          * @param ResourceLoaderContext $context Context to load the information within
  88          */
  89         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  90                 if ( !count( $modules ) ) {
  91                         // Or else Database*::select() will explode, plus it's cheaper!
  92                         return;
  93                 }
  94                 $dbr = wfGetDB( DB_SLAVE );
  95                 $skin = $context->getSkin();
  96                 $lang = $context->getLanguage();
  97
  98                 // Get file dependency information
  99                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 100                                 'md_module' => $modules,
 101                                 'md_skin' => $skin
 102                         ), __METHOD__
 103                 );
 104
 105                 // Set modules' dependencies
 106                 $modulesWithDeps = array();
 107                 foreach ( $res as $row ) {
 108                         $module = $this->getModule( $row->md_module );
 109                         if ( $module ) {
 110                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 111                                 $modulesWithDeps[] = $row->md_module;
 112                         }
 113                 }
 114
 115                 // Register the absence of a dependency row too
 116                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 117                         $module = $this->getModule( $name );
 118                         if ( $module ) {
 119                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 120                         }
 121                 }
 122
 123                 // Get message blob mtimes. Only do this for modules with messages
 124                 $modulesWithMessages = array();
 125                 foreach ( $modules as $name ) {
 126                         $module = $this->getModule( $name );
 127                         if ( $module && count( $module->getMessages() ) ) {
 128                                 $modulesWithMessages[] = $name;
 129                         }
 130                 }
 131                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 132                 if ( count( $modulesWithMessages ) ) {
 133                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 134                                         'mr_resource' => $modulesWithMessages,
 135                                         'mr_lang' => $lang
 136                                 ), __METHOD__
 137                         );
 138                         foreach ( $res as $row ) {
 139                                 $module = $this->getModule( $row->mr_resource );
 140                                 if ( $module ) {
 141                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 142                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 143                                 }
 144                         }
 145                 }
 146                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 147                         $module = $this->getModule( $name );
 148                         if ( $module ) {
 149                                 $module->setMsgBlobMtime( $lang, 1 );
 150                         }
 151                 }
 152         }
 153
 154         /**
 155          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 156          *
 157          * Available filters are:
 158          *
 159          *    - minify-js \see JavaScriptMinifier::minify
 160          *    - minify-css \see CSSMin::minify
 161          *
 162          * If $data is empty, only contains whitespace or the filter was unknown,
 163          * $data is returned unmodified.
 164          *
 165          * @param string $filter Name of filter to run
 166          * @param string $data Text to filter, such as JavaScript or CSS text
 167          * @param string $cacheReport Whether to include the cache key report
 168          * @return string Filtered data, or a comment containing an error message
 169          */
 170         public function filter( $filter, $data, $cacheReport = true ) {
 171
 172                 // For empty/whitespace-only data or for unknown filters, don't perform
 173                 // any caching or processing
 174                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 175                         return $data;
 176                 }
 177
 178                 // Try for cache hit
 179                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 180                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 181                 $cache = wfGetCache( CACHE_ANYTHING );
 182                 $cacheEntry = $cache->get( $key );
 183                 if ( is_string( $cacheEntry ) ) {
 184                         wfIncrStats( "rl-$filter-cache-hits" );
 185                         return $cacheEntry;
 186                 }
 187
 188                 $result = '';
 189                 // Run the filter - we've already verified one of these will work
 190                 try {
 191                         wfIncrStats( "rl-$filter-cache-misses" );
 192                         switch ( $filter ) {
 193                                 case 'minify-js':
 194                                         $result = JavaScriptMinifier::minify( $data,
 195                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 196                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 197                                         );
 198                                         if ( $cacheReport ) {
 199                                                 $result .= "\n/* cache key: $key */";
 200                                         }
 201                                         break;
 202                                 case 'minify-css':
 203                                         $result = CSSMin::minify( $data );
 204                                         if ( $cacheReport ) {
 205                                                 $result .= "\n/* cache key: $key */";
 206                                         }
 207                                         break;
 208                         }
 209
 210                         // Save filtered text to Memcached
 211                         $cache->set( $key, $result );
 212                 } catch ( Exception $e ) {
 213                         MWExceptionHandler::logException( $e );
 214                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 215                         $this->errors[] = self::formatExceptionNoComment( $e );
 216                 }
 217
 218                 return $result;
 219         }
 220
 221         /* Methods */
 222
 223         /**
 224          * Register core modules and runs registration hooks.
 225          * @param Config|null $config
 226          */
 227         public function __construct( Config $config = null ) {
 228                 global $IP;
 229
 230                 if ( $config === null ) {
 231                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 232                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 233                 }
 234
 235                 $this->config = $config;
 236
 237                 // Add 'local' source first
 238                 $this->addSource( 'local', wfScript( 'load' ) );
 239
 240                 // Add other sources
 241                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 242
 243                 // Register core modules
 244                 $this->register( include "$IP/resources/Resources.php" );
 245                 // Register extension modules
 246                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 247                 $this->register( $config->get( 'ResourceModules' ) );
 248
 249                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 250                         $this->registerTestModules();
 251                 }
 252
 253         }
 254
 255         /**
 256          * @return Config
 257          */
 258         public function getConfig() {
 259                 return $this->config;
 260         }
 261
 262         /**
 263          * Register a module with the ResourceLoader system.
 264          *
 265          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 266          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 267          *   this may also be a ResourceLoaderModule object. Optional when using
 268          *   multiple-registration calling style.
 269          * @throws MWException If a duplicate module registration is attempted
 270          * @throws MWException If a module name contains illegal characters (pipes or commas)
 271          * @throws MWException If something other than a ResourceLoaderModule is being registered
 272          * @return bool False if there were any errors, in which case one or more modules were
 273          *   not registered
 274          */
 275         public function register( $name, $info = null ) {
 276
 277                 // Allow multiple modules to be registered in one call
 278                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 279                 foreach ( $registrations as $name => $info ) {
 280                         // Disallow duplicate registrations
 281                         if ( isset( $this->moduleInfos[$name] ) ) {
 282                                 // A module has already been registered by this name
 283                                 throw new MWException(
 284                                         'ResourceLoader duplicate registration error. ' .
 285                                         'Another module has already been registered as ' . $name
 286                                 );
 287                         }
 288
 289                         // Check $name for validity
 290                         if ( !self::isValidModuleName( $name ) ) {
 291                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 292                                         . "see ResourceLoader::isValidModuleName()" );
 293                         }
 294
 295                         // Attach module
 296                         if ( $info instanceof ResourceLoaderModule ) {
 297                                 $this->moduleInfos[$name] = array( 'object' => $info );
 298                                 $info->setName( $name );
 299                                 $this->modules[$name] = $info;
 300                         } elseif ( is_array( $info ) ) {
 301                                 // New calling convention
 302                                 $this->moduleInfos[$name] = $info;
 303                         } else {
 304                                 throw new MWException(
 305                                         'ResourceLoader module info type error for module \'' . $name .
 306                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 307                                 );
 308                         }
 309
 310                         // Last-minute changes
 311
 312                         // Apply custom skin-defined styles to existing modules.
 313                         if ( $this->isFileModule( $name ) ) {
 314                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 315                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 316                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 317                                                 continue;
 318                                         }
 319
 320                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 321                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 322                                         if ( isset( $skinStyles[$name] ) ) {
 323                                                 $paths = (array)$skinStyles[$name];
 324                                                 $styleFiles = array();
 325                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 326                                                 $paths = (array)$skinStyles['+' . $name];
 327                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 328                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 329                                                         array();
 330                                         } else {
 331                                                 continue;
 332                                         }
 333
 334                                         // Add new file paths, remapping them to refer to our directories and not use settings
 335                                         // from the module we're modifying. These can come from the base definition or be defined
 336                                         // for each module.
 337                                         list( $localBasePath, $remoteBasePath ) =
 338                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 339                                         list( $localBasePath, $remoteBasePath ) =
 340                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 341
 342                                         foreach ( $paths as $path ) {
 343                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 344                                         }
 345
 346                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 347                                 }
 348                         }
 349                 }
 350
 351         }
 352
 353         /**
 354          */
 355         public function registerTestModules() {
 356                 global $IP;
 357
 358                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 359                         throw new MWException( 'Attempt to register JavaScript test modules '
 360                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 361                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 362                 }
 363
 364                 // Get core test suites
 365                 $testModules = array();
 366                 $testModules['qunit'] = array();
 367                 // Get other test suites (e.g. from extensions)
 368                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 369
 370                 // Add the testrunner (which configures QUnit) to the dependencies.
 371                 // Since it must be ready before any of the test suites are executed.
 372                 foreach ( $testModules['qunit'] as &$module ) {
 373                         // Make sure all test modules are top-loading so that when QUnit starts
 374                         // on document-ready, it will run once and finish. If some tests arrive
 375                         // later (possibly after QUnit has already finished) they will be ignored.
 376                         $module['position'] = 'top';
 377                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 378                 }
 379
 380                 $testModules['qunit'] =
 381                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 382
 383                 foreach ( $testModules as $id => $names ) {
 384                         // Register test modules
 385                         $this->register( $testModules[$id] );
 386
 387                         // Keep track of their names so that they can be loaded together
 388                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 389                 }
 390
 391         }
 392
 393         /**
 394          * Add a foreign source of modules.
 395          *
 396          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 397          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 398          *  backwards-compatibility.
 399          * @throws MWException
 400          */
 401         public function addSource( $id, $loadUrl = null ) {
 402                 // Allow multiple sources to be registered in one call
 403                 if ( is_array( $id ) ) {
 404                         foreach ( $id as $key => $value ) {
 405                                 $this->addSource( $key, $value );
 406                         }
 407                         return;
 408                 }
 409
 410                 // Disallow duplicates
 411                 if ( isset( $this->sources[$id] ) ) {
 412                         throw new MWException(
 413                                 'ResourceLoader duplicate source addition error. ' .
 414                                 'Another source has already been registered as ' . $id
 415                         );
 416                 }
 417
 418                 // Pre 1.24 backwards-compatibility
 419                 if ( is_array( $loadUrl ) ) {
 420                         if ( !isset( $loadUrl['loadScript'] ) ) {
 421                                 throw new MWException(
 422                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 423                                 );
 424                         }
 425
 426                         $loadUrl = $loadUrl['loadScript'];
 427                 }
 428
 429                 $this->sources[$id] = $loadUrl;
 430         }
 431
 432         /**
 433          * Get a list of module names.
 434          *
 435          * @return array List of module names
 436          */
 437         public function getModuleNames() {
 438                 return array_keys( $this->moduleInfos );
 439         }
 440
 441         /**
 442          * Get a list of test module names for one (or all) frameworks.
 443          *
 444          * If the given framework id is unknkown, or if the in-object variable is not an array,
 445          * then it will return an empty array.
 446          *
 447          * @param string $framework Get only the test module names for one
 448          *   particular framework (optional)
 449          * @return array
 450          */
 451         public function getTestModuleNames( $framework = 'all' ) {
 452                 /** @todo api siteinfo prop testmodulenames modulenames */
 453                 if ( $framework == 'all' ) {
 454                         return $this->testModuleNames;
 455                 } elseif ( isset( $this->testModuleNames[$framework] )
 456                         && is_array( $this->testModuleNames[$framework] )
 457                 ) {
 458                         return $this->testModuleNames[$framework];
 459                 } else {
 460                         return array();
 461                 }
 462         }
 463
 464         /**
 465          * Get the ResourceLoaderModule object for a given module name.
 466          *
 467          * If an array of module parameters exists but a ResourceLoaderModule object has not
 468          * yet been instantiated, this method will instantiate and cache that object such that
 469          * subsequent calls simply return the same object.
 470          *
 471          * @param string $name Module name
 472          * @return ResourceLoaderModule|null If module has been registered, return a
 473          *  ResourceLoaderModule instance. Otherwise, return null.
 474          */
 475         public function getModule( $name ) {
 476                 if ( !isset( $this->modules[$name] ) ) {
 477                         if ( !isset( $this->moduleInfos[$name] ) ) {
 478                                 // No such module
 479                                 return null;
 480                         }
 481                         // Construct the requested object
 482                         $info = $this->moduleInfos[$name];
 483                         /** @var ResourceLoaderModule $object */
 484                         if ( isset( $info['object'] ) ) {
 485                                 // Object given in info array
 486                                 $object = $info['object'];
 487                         } else {
 488                                 if ( !isset( $info['class'] ) ) {
 489                                         $class = 'ResourceLoaderFileModule';
 490                                 } else {
 491                                         $class = $info['class'];
 492                                 }
 493                                 /** @var ResourceLoaderModule $object */
 494                                 $object = new $class( $info );
 495                                 $object->setConfig( $this->getConfig() );
 496                         }
 497                         $object->setName( $name );
 498                         $this->modules[$name] = $object;
 499                 }
 500
 501                 return $this->modules[$name];
 502         }
 503
 504         /**
 505          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 506          *
 507          * @param string $name Module name
 508          * @return bool
 509          */
 510         protected function isFileModule( $name ) {
 511                 if ( !isset( $this->moduleInfos[$name] ) ) {
 512                         return false;
 513                 }
 514                 $info = $this->moduleInfos[$name];
 515                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 516                         return false;
 517                 }
 518                 return true;
 519         }
 520
 521         /**
 522          * Get the list of sources.
 523          *
 524          * @return array Like array( id => load.php url, .. )
 525          */
 526         public function getSources() {
 527                 return $this->sources;
 528         }
 529
 530         /**
 531          * Get the URL to the load.php endpoint for the given
 532          * ResourceLoader source
 533          *
 534          * @since 1.24
 535          * @param string $source
 536          * @throws MWException On an invalid $source name
 537          * @return string
 538          */
 539         public function getLoadScript( $source ) {
 540                 if ( !isset( $this->sources[$source] ) ) {
 541                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 542                 }
 543                 return $this->sources[$source];
 544         }
 545
 546         /**
 547          * Output a response to a load request, including the content-type header.
 548          *
 549          * @param ResourceLoaderContext $context Context in which a response should be formed
 550          */
 551         public function respond( ResourceLoaderContext $context ) {
 552                 // Use file cache if enabled and available...
 553                 if ( $this->config->get( 'UseFileCache' ) ) {
 554                         $fileCache = ResourceFileCache::newFromContext( $context );
 555                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 556                                 return; // output handled
 557                         }
 558                 }
 559
 560                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 561                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 562                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 563                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 564                 // the whole thing in our own output buffer to be sure the active buffer
 565                 // doesn't use ob_gzhandler.
 566                 // See http://bugs.php.net/bug.php?id=36514
 567                 ob_start();
 568
 569                 // Find out which modules are missing and instantiate the others
 570                 $modules = array();
 571                 $missing = array();
 572                 foreach ( $context->getModules() as $name ) {
 573                         $module = $this->getModule( $name );
 574                         if ( $module ) {
 575                                 // Do not allow private modules to be loaded from the web.
 576                                 // This is a security issue, see bug 34907.
 577                                 if ( $module->getGroup() === 'private' ) {
 578                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 579                                         $this->errors[] = "Cannot show private module \"$name\"";
 580                                         continue;
 581                                 }
 582                                 $modules[$name] = $module;
 583                         } else {
 584                                 $missing[] = $name;
 585                         }
 586                 }
 587
 588                 // Preload information needed to the mtime calculation below
 589                 try {
 590                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 591                 } catch ( Exception $e ) {
 592                         MWExceptionHandler::logException( $e );
 593                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 594                         $this->errors[] = self::formatExceptionNoComment( $e );
 595                 }
 596
 597                 // To send Last-Modified and support If-Modified-Since, we need to detect
 598                 // the last modified time
 599                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 600                 foreach ( $modules as $module ) {
 601                         /**
 602                          * @var $module ResourceLoaderModule
 603                          */
 604                         try {
 605                                 // Calculate maximum modified time
 606                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 607                         } catch ( Exception $e ) {
 608                                 MWExceptionHandler::logException( $e );
 609                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 610                                 $this->errors[] = self::formatExceptionNoComment( $e );
 611                         }
 612                 }
 613
 614                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 615                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 616                         return; // output handled (buffers cleared)
 617                 }
 618
 619                 // Generate a response
 620                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 621
 622                 // Capture any PHP warnings from the output buffer and append them to the
 623                 // error list if we're in debug mode.
 624                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 625                         $this->errors[] = $warnings;
 626                 }
 627
 628                 // Save response to file cache unless there are errors
 629                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 630                         // Cache single modules and images...and other requests if there are enough hits
 631                         if ( ResourceFileCache::useFileCache( $context ) ) {
 632                                 if ( $fileCache->isCacheWorthy() ) {
 633                                         $fileCache->saveText( $response );
 634                                 } else {
 635                                         $fileCache->incrMissesRecent( $context->getRequest() );
 636                                 }
 637                         }
 638                 }
 639
 640                 // Send content type and cache related headers
 641                 $this->sendResponseHeaders( $context, $mtime, (bool)$this->errors );
 642
 643                 // Remove the output buffer and output the response
 644                 ob_end_clean();
 645
 646                 if ( $context->getImageObj() && $this->errors ) {
 647                         // We can't show both the error messages and the response when it's an image.
 648                         $errorText = '';
 649                         foreach ( $this->errors as $error ) {
 650                                 $errorText .= $error . "\n";
 651                         }
 652                         $response = $errorText;
 653                 } elseif ( $this->errors ) {
 654                         // Prepend comments indicating errors
 655                         $errorText = '';
 656                         foreach ( $this->errors as $error ) {
 657                                 $errorText .= self::makeComment( $error );
 658                         }
 659                         $response = $errorText . $response;
 660                 }
 661
 662                 $this->errors = array();
 663                 echo $response;
 664
 665         }
 666
 667         /**
 668          * Send content type and last modified headers to the client.
 669          * @param ResourceLoaderContext $context
 670          * @param string $mtime TS_MW timestamp to use for last-modified
 671          * @param bool $errors Whether there are errors in the response
 672          * @return void
 673          */
 674         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 675                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 676                 // If a version wasn't specified we need a shorter expiry time for updates
 677                 // to propagate to clients quickly
 678                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 679                 if ( is_null( $context->getVersion() ) || $errors ) {
 680                         $maxage = $rlMaxage['unversioned']['client'];
 681                         $smaxage = $rlMaxage['unversioned']['server'];
 682                 // If a version was specified we can use a longer expiry time since changing
 683                 // version numbers causes cache misses
 684                 } else {
 685                         $maxage = $rlMaxage['versioned']['client'];
 686                         $smaxage = $rlMaxage['versioned']['server'];
 687                 }
 688                 if ( $context->getImageObj() ) {
 689                         // Output different headers if we're outputting textual errors.
 690                         if ( $errors ) {
 691                                 header( 'Content-Type: text/plain; charset=utf-8' );
 692                         } else {
 693                                 $context->getImageObj()->sendResponseHeaders( $context );
 694                         }
 695                 } elseif ( $context->getOnly() === 'styles' ) {
 696                         header( 'Content-Type: text/css; charset=utf-8' );
 697                         header( 'Access-Control-Allow-Origin: *' );
 698                 } else {
 699                         header( 'Content-Type: text/javascript; charset=utf-8' );
 700                 }
 701                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 702                 if ( $context->getDebug() ) {
 703                         // Do not cache debug responses
 704                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 705                         header( 'Pragma: no-cache' );
 706                 } else {
 707                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 708                         $exp = min( $maxage, $smaxage );
 709                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 710                 }
 711         }
 712
 713         /**
 714          * Respond with 304 Last Modified if appropiate.
 715          *
 716          * If there's an If-Modified-Since header, respond with a 304 appropriately
 717          * and clear out the output buffer. If the client cache is too old then do nothing.
 718          *
 719          * @param ResourceLoaderContext $context
 720          * @param string $mtime The TS_MW timestamp to check the header against
 721          * @return bool True if 304 header sent and output handled
 722          */
 723         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 724                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 725                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 726                 // so we get a valid timestamp.
 727                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 728                 // Never send 304s in debug mode
 729                 if ( $ims !== false && !$context->getDebug() ) {
 730                         $imsTS = strtok( $ims, ';' );
 731                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 732                                 // There's another bug in ob_gzhandler (see also the comment at
 733                                 // the top of this function) that causes it to gzip even empty
 734                                 // responses, meaning it's impossible to produce a truly empty
 735                                 // response (because the gzip header is always there). This is
 736                                 // a problem because 304 responses have to be completely empty
 737                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 738                                 // See also http://bugs.php.net/bug.php?id=51579
 739                                 // To work around this, we tear down all output buffering before
 740                                 // sending the 304.
 741                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 742
 743                                 header( 'HTTP/1.0 304 Not Modified' );
 744                                 header( 'Status: 304 Not Modified' );
 745                                 return true;
 746                         }
 747                 }
 748                 return false;
 749         }
 750
 751         /**
 752          * Send out code for a response from file cache if possible.
 753          *
 754          * @param ResourceFileCache $fileCache Cache object for this request URL
 755          * @param ResourceLoaderContext $context Context in which to generate a response
 756          * @return bool If this found a cache file and handled the response
 757          */
 758         protected function tryRespondFromFileCache(
 759                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 760         ) {
 761                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 762                 // Buffer output to catch warnings.
 763                 ob_start();
 764                 // Get the maximum age the cache can be
 765                 $maxage = is_null( $context->getVersion() )
 766                         ? $rlMaxage['unversioned']['server']
 767                         : $rlMaxage['versioned']['server'];
 768                 // Minimum timestamp the cache file must have
 769                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 770                 if ( !$good ) {
 771                         try { // RL always hits the DB on file cache miss...
 772                                 wfGetDB( DB_SLAVE );
 773                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 774                                 $good = $fileCache->isCacheGood(); // cache existence check
 775                         }
 776                 }
 777                 if ( $good ) {
 778                         $ts = $fileCache->cacheTimestamp();
 779                         // Send content type and cache headers
 780                         $this->sendResponseHeaders( $context, $ts, false );
 781                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 782                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 783                                 return false; // output handled (buffers cleared)
 784                         }
 785                         $response = $fileCache->fetchText();
 786                         // Capture any PHP warnings from the output buffer and append them to the
 787                         // response in a comment if we're in debug mode.
 788                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 789                                 $response = "/*\n$warnings\n*/\n" . $response;
 790                         }
 791                         // Remove the output buffer and output the response
 792                         ob_end_clean();
 793                         echo $response . "\n/* Cached {$ts} */";
 794                         return true; // cache hit
 795                 }
 796                 // Clear buffer
 797                 ob_end_clean();
 798
 799                 return false; // cache miss
 800         }
 801
 802         /**
 803          * Generate a CSS or JS comment block.
 804          *
 805          * Only use this for public data, not error message details.
 806          *
 807          * @param string $text
 808          * @return string
 809          */
 810         public static function makeComment( $text ) {
 811                 $encText = str_replace( '*/', '* /', $text );
 812                 return "/*\n$encText\n*/\n";
 813         }
 814
 815         /**
 816          * Handle exception display.
 817          *
 818          * @param Exception $e Exception to be shown to the user
 819          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 820          */
 821         public static function formatException( $e ) {
 822                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 823         }
 824
 825         /**
 826          * Handle exception display.
 827          *
 828          * @since 1.25
 829          * @param Exception $e Exception to be shown to the user
 830          * @return string Sanitized text that can be returned to the user
 831          */
 832         protected static function formatExceptionNoComment( $e ) {
 833                 global $wgShowExceptionDetails;
 834
 835                 if ( $wgShowExceptionDetails ) {
 836                         return $e->__toString();
 837                 } else {
 838                         return wfMessage( 'internalerror' )->text();
 839                 }
 840         }
 841
 842         /**
 843          * Generate code for a response.
 844          *
 845          * @param ResourceLoaderContext $context Context in which to generate a response
 846          * @param array $modules List of module objects keyed by module name
 847          * @param array $missing List of requested module names that are unregistered (optional)
 848          * @return string Response data
 849          */
 850         public function makeModuleResponse( ResourceLoaderContext $context,
 851                 array $modules, array $missing = array()
 852         ) {
 853                 $out = '';
 854                 $states = array();
 855
 856                 if ( !count( $modules ) && !count( $missing ) ) {
 857                         return <<<MESSAGE
 858 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 859    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 860    no modules were requested. Max made me put this here. */
 861 MESSAGE;
 862                 }
 863
 864                 $image = $context->getImageObj();
 865                 if ( $image ) {
 866                         $data = $image->getImageData( $context );
 867                         if ( $data === false ) {
 868                                 $data = '';
 869                                 $this->errors[] = 'Image generation failed';
 870                         }
 871                         return $data;
 872                 }
 873
 874                 // Pre-fetch blobs
 875                 if ( $context->shouldIncludeMessages() ) {
 876                         try {
 877                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 878                         } catch ( Exception $e ) {
 879                                 MWExceptionHandler::logException( $e );
 880                                 wfDebugLog(
 881                                         'resourceloader',
 882                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 883                                 );
 884                                 $this->errors[] = self::formatExceptionNoComment( $e );
 885                         }
 886                 } else {
 887                         $blobs = array();
 888                 }
 889
 890                 foreach ( $missing as $name ) {
 891                         $states[$name] = 'missing';
 892                 }
 893
 894                 // Generate output
 895                 $isRaw = false;
 896                 foreach ( $modules as $name => $module ) {
 897                         /**
 898                          * @var $module ResourceLoaderModule
 899                          */
 900
 901                         try {
 902                                 $scripts = '';
 903                                 if ( $context->shouldIncludeScripts() ) {
 904                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 905                                         // However, we can't do this if the module doesn't support it
 906                                         // We also can't do this if there is an only= parameter, because we have to give
 907                                         // the module a way to return a load.php URL without causing an infinite loop
 908                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 909                                                 $scripts = $module->getScriptURLsForDebug( $context );
 910                                         } else {
 911                                                 $scripts = $module->getScript( $context );
 912                                                 // rtrim() because there are usually a few line breaks
 913                                                 // after the last ';'. A new line at EOF, a new line
 914                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 915                                                 if ( is_string( $scripts )
 916                                                         && strlen( $scripts )
 917                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 918                                                 ) {
 919                                                         // Append semicolon to prevent weird bugs caused by files not
 920                                                         // terminating their statements right (bug 27054)
 921                                                         $scripts .= ";\n";
 922                                                 }
 923                                         }
 924                                 }
 925                                 // Styles
 926                                 $styles = array();
 927                                 if ( $context->shouldIncludeStyles() ) {
 928                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 929                                         // that don't *have* any stylesheets (bug 38024).
 930                                         $stylePairs = $module->getStyles( $context );
 931                                         if ( count( $stylePairs ) ) {
 932                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 933                                                 // See comment near shouldIncludeScripts() for more details
 934                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 935                                                         $styles = array(
 936                                                                 'url' => $module->getStyleURLsForDebug( $context )
 937                                                         );
 938                                                 } else {
 939                                                         // Minify CSS before embedding in mw.loader.implement call
 940                                                         // (unless in debug mode)
 941                                                         if ( !$context->getDebug() ) {
 942                                                                 foreach ( $stylePairs as $media => $style ) {
 943                                                                         // Can be either a string or an array of strings.
 944                                                                         if ( is_array( $style ) ) {
 945                                                                                 $stylePairs[$media] = array();
 946                                                                                 foreach ( $style as $cssText ) {
 947                                                                                         if ( is_string( $cssText ) ) {
 948                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 949                                                                                         }
 950                                                                                 }
 951                                                                         } elseif ( is_string( $style ) ) {
 952                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 953                                                                         }
 954                                                                 }
 955                                                         }
 956                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 957                                                         $styles = array(
 958                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 959                                                         );
 960                                                 }
 961                                         }
 962                                 }
 963
 964                                 // Messages
 965                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 966
 967                                 // Append output
 968                                 switch ( $context->getOnly() ) {
 969                                         case 'scripts':
 970                                                 if ( is_string( $scripts ) ) {
 971                                                         // Load scripts raw...
 972                                                         $out .= $scripts;
 973                                                 } elseif ( is_array( $scripts ) ) {
 974                                                         // ...except when $scripts is an array of URLs
 975                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 976                                                 }
 977                                                 break;
 978                                         case 'styles':
 979                                                 // We no longer seperate into media, they are all combined now with
 980                                                 // custom media type groups into @media .. {} sections as part of the css string.
 981                                                 // Module returns either an empty array or a numerical array with css strings.
 982                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 983                                                 break;
 984                                         case 'messages':
 985                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 986                                                 break;
 987                                         case 'templates':
 988                                                 $out .= Xml::encodeJsCall(
 989                                                         'mw.templates.set',
 990                                                         array( $name, (object)$module->getTemplates() ),
 991                                                         ResourceLoader::inDebugMode()
 992                                                 );
 993                                                 break;
 994                                         default:
 995                                                 $out .= self::makeLoaderImplementScript(
 996                                                         $name,
 997                                                         $scripts,
 998                                                         $styles,
 999                                                         new XmlJsCode( $messagesBlob ),
1000                                                         $module->getTemplates()
1001                                                 );
1002                                                 break;
1003                                 }
1004                         } catch ( Exception $e ) {
1005                                 MWExceptionHandler::logException( $e );
1006                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1007                                 $this->errors[] = self::formatExceptionNoComment( $e );
1008
1009                                 // Respond to client with error-state instead of module implementation
1010                                 $states[$name] = 'error';
1011                                 unset( $modules[$name] );
1012                         }
1013                         $isRaw |= $module->isRaw();
1014                 }
1015
1016                 // Update module states
1017                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1018                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1019                                 // Set the state of modules loaded as only scripts to ready as
1020                                 // they don't have an mw.loader.implement wrapper that sets the state
1021                                 foreach ( $modules as $name => $module ) {
1022                                         $states[$name] = 'ready';
1023                                 }
1024                         }
1025
1026                         // Set the state of modules we didn't respond to with mw.loader.implement
1027                         if ( count( $states ) ) {
1028                                 $out .= self::makeLoaderStateScript( $states );
1029                         }
1030                 } else {
1031                         if ( count( $states ) ) {
1032                                 $this->errors[] = 'Problematic modules: ' .
1033                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1034                         }
1035                 }
1036
1037                 if ( !$context->getDebug() ) {
1038                         if ( $context->getOnly() === 'styles' ) {
1039                                 $out = $this->filter( 'minify-css', $out );
1040                         } else {
1041                                 $out = $this->filter( 'minify-js', $out );
1042                         }
1043                 }
1044
1045                 return $out;
1046         }
1047
1048         /* Static Methods */
1049
1050         /**
1051          * Return JS code that calls mw.loader.implement with given module properties.
1052          *
1053          * @param string $name Module name
1054          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1055          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1056          *   to CSS files keyed by media type
1057          * @param mixed $messages List of messages associated with this module. May either be an
1058          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1059          *   the same data, wrapped in an XmlJsCode object.
1060          * @param array $templates Keys are name of templates and values are the source of
1061          *   the template.
1062          * @throws MWException
1063          * @return string
1064          */
1065         public static function makeLoaderImplementScript( $name, $scripts, $styles,
1066                 $messages, $templates
1067         ) {
1068                 if ( is_string( $scripts ) ) {
1069                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1070                 } elseif ( !is_array( $scripts ) ) {
1071                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1072                 }
1073
1074                 return Xml::encodeJsCall(
1075                         'mw.loader.implement',
1076                         array(
1077                                 $name,
1078                                 $scripts,
1079                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1080                                 // Although these variables are associative arrays, which become javascript
1081                                 // objects through json_encode. In many cases they will be empty arrays, and
1082                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1083                                 // output javascript "[]" instead of "{}". This fixes that.
1084                                 (object)$styles,
1085                                 (object)$messages,
1086                                 (object)$templates,
1087                         ),
1088                         ResourceLoader::inDebugMode()
1089                 );
1090         }
1091
1092         /**
1093          * Returns JS code which, when called, will register a given list of messages.
1094          *
1095          * @param mixed $messages Either an associative array mapping message key to value, or a
1096          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1097          * @return string
1098          */
1099         public static function makeMessageSetScript( $messages ) {
1100                 return Xml::encodeJsCall(
1101                         'mw.messages.set',
1102                         array( (object)$messages ),
1103                         ResourceLoader::inDebugMode()
1104                 );
1105         }
1106
1107         /**
1108          * Combines an associative array mapping media type to CSS into a
1109          * single stylesheet with "@media" blocks.
1110          *
1111          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1112          * @return array
1113          */
1114         public static function makeCombinedStyles( array $stylePairs ) {
1115                 $out = array();
1116                 foreach ( $stylePairs as $media => $styles ) {
1117                         // ResourceLoaderFileModule::getStyle can return the styles
1118                         // as a string or an array of strings. This is to allow separation in
1119                         // the front-end.
1120                         $styles = (array)$styles;
1121                         foreach ( $styles as $style ) {
1122                                 $style = trim( $style );
1123                                 // Don't output an empty "@media print { }" block (bug 40498)
1124                                 if ( $style !== '' ) {
1125                                         // Transform the media type based on request params and config
1126                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1127                                         $media = OutputPage::transformCssMedia( $media );
1128
1129                                         if ( $media === '' || $media == 'all' ) {
1130                                                 $out[] = $style;
1131                                         } elseif ( is_string( $media ) ) {
1132                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1133                                         }
1134                                         // else: skip
1135                                 }
1136                         }
1137                 }
1138                 return $out;
1139         }
1140
1141         /**
1142          * Returns a JS call to mw.loader.state, which sets the state of a
1143          * module or modules to a given value. Has two calling conventions:
1144          *
1145          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1146          *         Set the state of a single module called $name to $state
1147          *
1148          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1149          *         Set the state of modules with the given names to the given states
1150          *
1151          * @param string $name
1152          * @param string $state
1153          * @return string
1154          */
1155         public static function makeLoaderStateScript( $name, $state = null ) {
1156                 if ( is_array( $name ) ) {
1157                         return Xml::encodeJsCall(
1158                                 'mw.loader.state',
1159                                 array( $name ),
1160                                 ResourceLoader::inDebugMode()
1161                         );
1162                 } else {
1163                         return Xml::encodeJsCall(
1164                                 'mw.loader.state',
1165                                 array( $name, $state ),
1166                                 ResourceLoader::inDebugMode()
1167                         );
1168                 }
1169         }
1170
1171         /**
1172          * Returns JS code which calls the script given by $script. The script will
1173          * be called with local variables name, version, dependencies and group,
1174          * which will have values corresponding to $name, $version, $dependencies
1175          * and $group as supplied.
1176          *
1177          * @param string $name Module name
1178          * @param int $version Module version number as a timestamp
1179          * @param array $dependencies List of module names on which this module depends
1180          * @param string $group Group which the module is in.
1181          * @param string $source Source of the module, or 'local' if not foreign.
1182          * @param string $script JavaScript code
1183          * @return string
1184          */
1185         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1186                 $group, $source, $script
1187         ) {
1188                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1189                 return Xml::encodeJsCall(
1190                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1191                         array( $name, $version, $dependencies, $group, $source ),
1192                         ResourceLoader::inDebugMode()
1193                 );
1194         }
1195
1196         /**
1197          * Remove empty values from the end of an array.
1198          *
1199          * Values considered empty:
1200          *
1201          * - null
1202          * - empty array
1203          *
1204          * @param Array $array
1205          */
1206         private static function trimArray( Array &$array ) {
1207                 $i = count( $array );
1208                 while ( $i-- ) {
1209                         if ( $array[$i] === null || $array[$i] === array() ) {
1210                                 unset( $array[$i] );
1211                         } else {
1212                                 break;
1213                         }
1214                 }
1215         }
1216
1217         /**
1218          * Returns JS code which calls mw.loader.register with the given
1219          * parameters. Has three calling conventions:
1220          *
1221          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1222          *        $dependencies, $group, $source, $skip
1223          *     ):
1224          *        Register a single module.
1225          *
1226          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1227          *        Register modules with the given names.
1228          *
1229          *   - ResourceLoader::makeLoaderRegisterScript( array(
1230          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1231          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1232          *        ...
1233          *     ) ):
1234          *        Registers modules with the given names and parameters.
1235          *
1236          * @param string $name Module name
1237          * @param int $version Module version number as a timestamp
1238          * @param array $dependencies List of module names on which this module depends
1239          * @param string $group Group which the module is in
1240          * @param string $source Source of the module, or 'local' if not foreign
1241          * @param string $skip Script body of the skip function
1242          * @return string
1243          */
1244         public static function makeLoaderRegisterScript( $name, $version = null,
1245                 $dependencies = null, $group = null, $source = null, $skip = null
1246         ) {
1247                 if ( is_array( $name ) ) {
1248                         // Build module name index
1249                         $index = array();
1250                         foreach ( $name as $i => &$module ) {
1251                                 $index[$module[0]] = $i;
1252                         }
1253
1254                         // Transform dependency names into indexes when possible, they will be resolved by
1255                         // mw.loader.register on the other end
1256                         foreach ( $name as &$module ) {
1257                                 if ( isset( $module[2] ) ) {
1258                                         foreach ( $module[2] as &$dependency ) {
1259                                                 if ( isset( $index[$dependency] ) ) {
1260                                                         $dependency = $index[$dependency];
1261                                                 }
1262                                         }
1263                                 }
1264                         }
1265
1266                         array_walk( $name, array( 'self', 'trimArray' ) );
1267
1268                         return Xml::encodeJsCall(
1269                                 'mw.loader.register',
1270                                 array( $name ),
1271                                 ResourceLoader::inDebugMode()
1272                         );
1273                 } else {
1274                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1275                         self::trimArray( $registration );
1276                         return Xml::encodeJsCall(
1277                                 'mw.loader.register',
1278                                 $registration,
1279                                 ResourceLoader::inDebugMode()
1280                         );
1281                 }
1282         }
1283
1284         /**
1285          * Returns JS code which calls mw.loader.addSource() with the given
1286          * parameters. Has two calling conventions:
1287          *
1288          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1289          *       Register a single source
1290          *
1291          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1292          *       Register sources with the given IDs and properties.
1293          *
1294          * @param string $id Source ID
1295          * @param array $properties Source properties (see addSource())
1296          * @return string
1297          */
1298         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1299                 if ( is_array( $id ) ) {
1300                         return Xml::encodeJsCall(
1301                                 'mw.loader.addSource',
1302                                 array( $id ),
1303                                 ResourceLoader::inDebugMode()
1304                         );
1305                 } else {
1306                         return Xml::encodeJsCall(
1307                                 'mw.loader.addSource',
1308                                 array( $id, $properties ),
1309                                 ResourceLoader::inDebugMode()
1310                         );
1311                 }
1312         }
1313
1314         /**
1315          * Returns JS code which runs given JS code if the client-side framework is
1316          * present.
1317          *
1318          * @param string $script JavaScript code
1319          * @return string
1320          */
1321         public static function makeLoaderConditionalScript( $script ) {
1322                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1323         }
1324
1325         /**
1326          * Returns JS code which will set the MediaWiki configuration array to
1327          * the given value.
1328          *
1329          * @param array $configuration List of configuration values keyed by variable name
1330          * @return string
1331          */
1332         public static function makeConfigSetScript( array $configuration ) {
1333                 return Xml::encodeJsCall(
1334                         'mw.config.set',
1335                         array( $configuration ),
1336                         ResourceLoader::inDebugMode()
1337                 );
1338         }
1339
1340         /**
1341          * Convert an array of module names to a packed query string.
1342          *
1343          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1344          * becomes 'foo.bar,baz|bar.baz,quux'
1345          * @param array $modules List of module names (strings)
1346          * @return string Packed query string
1347          */
1348         public static function makePackedModulesString( $modules ) {
1349                 $groups = array(); // array( prefix => array( suffixes ) )
1350                 foreach ( $modules as $module ) {
1351                         $pos = strrpos( $module, '.' );
1352                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1353                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1354                         $groups[$prefix][] = $suffix;
1355                 }
1356
1357                 $arr = array();
1358                 foreach ( $groups as $prefix => $suffixes ) {
1359                         $p = $prefix === '' ? '' : $prefix . '.';
1360                         $arr[] = $p . implode( ',', $suffixes );
1361                 }
1362                 $str = implode( '|', $arr );
1363                 return $str;
1364         }
1365
1366         /**
1367          * Determine whether debug mode was requested
1368          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1369          * @return bool
1370          */
1371         public static function inDebugMode() {
1372                 if ( self::$debugMode === null ) {
1373                         global $wgRequest, $wgResourceLoaderDebug;
1374                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1375                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1376                         );
1377                 }
1378                 return self::$debugMode;
1379         }
1380
1381         /**
1382          * Reset static members used for caching.
1383          *
1384          * Global state and $wgRequest are evil, but we're using it right
1385          * now and sometimes we need to be able to force ResourceLoader to
1386          * re-evaluate the context because it has changed (e.g. in the test suite).
1387          */
1388         public static function clearCache() {
1389                 self::$debugMode = null;
1390         }
1391
1392         /**
1393          * Build a load.php URL
1394          *
1395          * @since 1.24
1396          * @param string $source Name of the ResourceLoader source
1397          * @param ResourceLoaderContext $context
1398          * @param array $extraQuery
1399          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1400          */
1401         public function createLoaderURL( $source, ResourceLoaderContext $context,
1402                 $extraQuery = array()
1403         ) {
1404                 $query = self::createLoaderQuery( $context, $extraQuery );
1405                 $script = $this->getLoadScript( $source );
1406
1407                 // Prevent the IE6 extension check from being triggered (bug 28840)
1408                 // by appending a character that's invalid in Windows extensions ('*')
1409                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1410         }
1411
1412         /**
1413          * Build a load.php URL
1414          * @deprecated since 1.24, use createLoaderURL instead
1415          * @param array $modules Array of module names (strings)
1416          * @param string $lang Language code
1417          * @param string $skin Skin name
1418          * @param string|null $user User name. If null, the &user= parameter is omitted
1419          * @param string|null $version Versioning timestamp
1420          * @param bool $debug Whether the request should be in debug mode
1421          * @param string|null $only &only= parameter
1422          * @param bool $printable Printable mode
1423          * @param bool $handheld Handheld mode
1424          * @param array $extraQuery Extra query parameters to add
1425          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1426          */
1427         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1428                 $version = null, $debug = false, $only = null, $printable = false,
1429                 $handheld = false, $extraQuery = array()
1430         ) {
1431                 global $wgLoadScript;
1432
1433                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1434                         $only, $printable, $handheld, $extraQuery
1435                 );
1436
1437                 // Prevent the IE6 extension check from being triggered (bug 28840)
1438                 // by appending a character that's invalid in Windows extensions ('*')
1439                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1440         }
1441
1442         /**
1443          * Helper for createLoaderURL()
1444          *
1445          * @since 1.24
1446          * @see makeLoaderQuery
1447          * @param ResourceLoaderContext $context
1448          * @param array $extraQuery
1449          * @return array
1450          */
1451         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1452                 return self::makeLoaderQuery(
1453                         $context->getModules(),
1454                         $context->getLanguage(),
1455                         $context->getSkin(),
1456                         $context->getUser(),
1457                         $context->getVersion(),
1458                         $context->getDebug(),
1459                         $context->getOnly(),
1460                         $context->getRequest()->getBool( 'printable' ),
1461                         $context->getRequest()->getBool( 'handheld' ),
1462                         $extraQuery
1463                 );
1464         }
1465
1466         /**
1467          * Build a query array (array representation of query string) for load.php. Helper
1468          * function for makeLoaderURL().
1469          *
1470          * @param array $modules
1471          * @param string $lang
1472          * @param string $skin
1473          * @param string $user
1474          * @param string $version
1475          * @param bool $debug
1476          * @param string $only
1477          * @param bool $printable
1478          * @param bool $handheld
1479          * @param array $extraQuery
1480          *
1481          * @return array
1482          */
1483         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1484                 $version = null, $debug = false, $only = null, $printable = false,
1485                 $handheld = false, $extraQuery = array()
1486         ) {
1487                 $query = array(
1488                         'modules' => self::makePackedModulesString( $modules ),
1489                         'lang' => $lang,
1490                         'skin' => $skin,
1491                         'debug' => $debug ? 'true' : 'false',
1492                 );
1493                 if ( $user !== null ) {
1494                         $query['user'] = $user;
1495                 }
1496                 if ( $version !== null ) {
1497                         $query['version'] = $version;
1498                 }
1499                 if ( $only !== null ) {
1500                         $query['only'] = $only;
1501                 }
1502                 if ( $printable ) {
1503                         $query['printable'] = 1;
1504                 }
1505                 if ( $handheld ) {
1506                         $query['handheld'] = 1;
1507                 }
1508                 $query += $extraQuery;
1509
1510                 // Make queries uniform in order
1511                 ksort( $query );
1512                 return $query;
1513         }
1514
1515         /**
1516          * Check a module name for validity.
1517          *
1518          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1519          * at most 255 bytes.
1520          *
1521          * @param string $moduleName Module name to check
1522          * @return bool Whether $moduleName is a valid module name
1523          */
1524         public static function isValidModuleName( $moduleName ) {
1525                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1526         }
1527
1528         /**
1529          * Returns LESS compiler set up for use with MediaWiki
1530          *
1531          * @param Config $config
1532          * @throws MWException
1533          * @since 1.22
1534          * @return lessc
1535          */
1536         public static function getLessCompiler( Config $config ) {
1537                 // When called from the installer, it is possible that a required PHP extension
1538                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1539                 // exception (caught by the installer) to prevent a fatal error later on.
1540                 if ( !class_exists( 'lessc' ) ) {
1541                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1542                 }
1543                 if ( !function_exists( 'ctype_digit' ) ) {
1544                         throw new MWException( 'lessc requires the Ctype extension' );
1545                 }
1546
1547                 $less = new lessc();
1548                 $less->setPreserveComments( true );
1549                 $less->setVariables( self::getLessVars( $config ) );
1550                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1551                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1552                         $less->registerFunction( $name, $func );
1553                 }
1554                 return $less;
1555         }
1556
1557         /**
1558          * Get global LESS variables.
1559          *
1560          * @param Config $config
1561          * @since 1.22
1562          * @return array Map of variable names to string CSS values.
1563          */
1564         public static function getLessVars( Config $config ) {
1565                 if ( !self::$lessVars ) {
1566                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1567                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1568                         // Sort by key to ensure consistent hashing for cache lookups.
1569                         ksort( $lessVars );
1570                         self::$lessVars = $lessVars;
1571                 }
1572                 return self::$lessVars;
1573         }
1574 }