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 array */
  36         protected static $requiredSourceProperties = array( 'loadScript' );
  37
  38         /** @var bool */
  39         protected static $debugMode = null;
  40
  41         /** @var array Module name/ResourceLoaderModule object pairs */
  42         protected $modules = array();
  43
  44         /** @var array Associative array mapping module name to info associative array */
  45         protected $moduleInfos = array();
  46
  47         /** @var Config $config */
  48         private $config;
  49
  50         /**
  51          * @var array Associative array mapping framework ids to a list of names of test suite modules
  52          *      like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  53          */
  54         protected $testModuleNames = array();
  55
  56         /** @var array E.g. array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) */
  57         protected $sources = array();
  58
  59         /** @var bool */
  60         protected $hasErrors = false;
  61
  62         /**
  63          * Load information stored in the database about modules.
  64          *
  65          * This method grabs modules dependencies from the database and updates modules
  66          * objects.
  67          *
  68          * This is not inside the module code because it is much faster to
  69          * request all of the information at once than it is to have each module
  70          * requests its own information. This sacrifice of modularity yields a substantial
  71          * performance improvement.
  72          *
  73          * @param array $modules List of module names to preload information for
  74          * @param ResourceLoaderContext $context Context to load the information within
  75          */
  76         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  77                 if ( !count( $modules ) ) {
  78                         // Or else Database*::select() will explode, plus it's cheaper!
  79                         return;
  80                 }
  81                 $dbr = wfGetDB( DB_SLAVE );
  82                 $skin = $context->getSkin();
  83                 $lang = $context->getLanguage();
  84
  85                 // Get file dependency information
  86                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  87                                 'md_module' => $modules,
  88                                 'md_skin' => $skin
  89                         ), __METHOD__
  90                 );
  91
  92                 // Set modules' dependencies
  93                 $modulesWithDeps = array();
  94                 foreach ( $res as $row ) {
  95                         $module = $this->getModule( $row->md_module );
  96                         if ( $module ) {
  97                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
  98                                 $modulesWithDeps[] = $row->md_module;
  99                         }
 100                 }
 101
 102                 // Register the absence of a dependency row too
 103                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 104                         $module = $this->getModule( $name );
 105                         if ( $module ) {
 106                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 107                         }
 108                 }
 109
 110                 // Get message blob mtimes. Only do this for modules with messages
 111                 $modulesWithMessages = array();
 112                 foreach ( $modules as $name ) {
 113                         $module = $this->getModule( $name );
 114                         if ( $module && count( $module->getMessages() ) ) {
 115                                 $modulesWithMessages[] = $name;
 116                         }
 117                 }
 118                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 119                 if ( count( $modulesWithMessages ) ) {
 120                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 121                                         'mr_resource' => $modulesWithMessages,
 122                                         'mr_lang' => $lang
 123                                 ), __METHOD__
 124                         );
 125                         foreach ( $res as $row ) {
 126                                 $module = $this->getModule( $row->mr_resource );
 127                                 if ( $module ) {
 128                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 129                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 130                                 }
 131                         }
 132                 }
 133                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 134                         $module = $this->getModule( $name );
 135                         if ( $module ) {
 136                                 $module->setMsgBlobMtime( $lang, 0 );
 137                         }
 138                 }
 139         }
 140
 141         /**
 142          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 143          *
 144          * Available filters are:
 145          *
 146          *    - minify-js \see JavaScriptMinifier::minify
 147          *    - minify-css \see CSSMin::minify
 148          *
 149          * If $data is empty, only contains whitespace or the filter was unknown,
 150          * $data is returned unmodified.
 151          *
 152          * @param string $filter Name of filter to run
 153          * @param string $data Text to filter, such as JavaScript or CSS text
 154          * @param string $cacheReport Whether to include the cache key report
 155          * @return string Filtered data, or a comment containing an error message
 156          */
 157         public function filter( $filter, $data, $cacheReport = true ) {
 158                 wfProfileIn( __METHOD__ );
 159
 160                 // For empty/whitespace-only data or for unknown filters, don't perform
 161                 // any caching or processing
 162                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 163                         wfProfileOut( __METHOD__ );
 164                         return $data;
 165                 }
 166
 167                 // Try for cache hit
 168                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 169                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 170                 $cache = wfGetCache( CACHE_ANYTHING );
 171                 $cacheEntry = $cache->get( $key );
 172                 if ( is_string( $cacheEntry ) ) {
 173                         wfIncrStats( "rl-$filter-cache-hits" );
 174                         wfProfileOut( __METHOD__ );
 175                         return $cacheEntry;
 176                 }
 177
 178                 $result = '';
 179                 // Run the filter - we've already verified one of these will work
 180                 try {
 181                         wfIncrStats( "rl-$filter-cache-misses" );
 182                         switch ( $filter ) {
 183                                 case 'minify-js':
 184                                         $result = JavaScriptMinifier::minify( $data,
 185                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 186                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 187                                         );
 188                                         if ( $cacheReport ) {
 189                                                 $result .= "\n/* cache key: $key */";
 190                                         }
 191                                         break;
 192                                 case 'minify-css':
 193                                         $result = CSSMin::minify( $data );
 194                                         if ( $cacheReport ) {
 195                                                 $result .= "\n/* cache key: $key */";
 196                                         }
 197                                         break;
 198                         }
 199
 200                         // Save filtered text to Memcached
 201                         $cache->set( $key, $result );
 202                 } catch ( Exception $e ) {
 203                         MWExceptionHandler::logException( $e );
 204                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 205                         $this->hasErrors = true;
 206                         // Return exception as a comment
 207                         $result = self::formatException( $e );
 208                 }
 209
 210                 wfProfileOut( __METHOD__ );
 211
 212                 return $result;
 213         }
 214
 215         /* Methods */
 216
 217         /**
 218          * Register core modules and runs registration hooks.
 219          * @param Config|null $config
 220          */
 221         public function __construct( Config $config = null ) {
 222                 global $IP;
 223
 224                 wfProfileIn( __METHOD__ );
 225
 226                 if ( $config === null ) {
 227                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 228                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 229                 }
 230
 231                 $this->config = $config;
 232
 233                 // Add 'local' source first
 234                 $this->addSource(
 235                         'local',
 236                         array( 'loadScript' => wfScript( 'load' ), 'apiScript' => wfScript( 'api' ) )
 237                 );
 238
 239                 // Add other sources
 240                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 241
 242                 // Register core modules
 243                 $this->register( include "$IP/resources/Resources.php" );
 244                 // Register extension modules
 245                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 246                 $this->register( $config->get( 'ResourceModules' ) );
 247
 248                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 249                         $this->registerTestModules();
 250                 }
 251
 252                 wfProfileOut( __METHOD__ );
 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                 wfProfileIn( __METHOD__ );
 277
 278                 // Allow multiple modules to be registered in one call
 279                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 280                 foreach ( $registrations as $name => $info ) {
 281                         // Disallow duplicate registrations
 282                         if ( isset( $this->moduleInfos[$name] ) ) {
 283                                 wfProfileOut( __METHOD__ );
 284                                 // A module has already been registered by this name
 285                                 throw new MWException(
 286                                         'ResourceLoader duplicate registration error. ' .
 287                                         'Another module has already been registered as ' . $name
 288                                 );
 289                         }
 290
 291                         // Check $name for validity
 292                         if ( !self::isValidModuleName( $name ) ) {
 293                                 wfProfileOut( __METHOD__ );
 294                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 295                                         . "see ResourceLoader::isValidModuleName()" );
 296                         }
 297
 298                         // Attach module
 299                         if ( $info instanceof ResourceLoaderModule ) {
 300                                 $this->moduleInfos[$name] = array( 'object' => $info );
 301                                 $info->setName( $name );
 302                                 $this->modules[$name] = $info;
 303                         } elseif ( is_array( $info ) ) {
 304                                 // New calling convention
 305                                 $this->moduleInfos[$name] = $info;
 306                         } else {
 307                                 wfProfileOut( __METHOD__ );
 308                                 throw new MWException(
 309                                         'ResourceLoader module info type error for module \'' . $name .
 310                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 311                                 );
 312                         }
 313
 314                         // Last-minute changes
 315
 316                         // Apply custom skin-defined styles to existing modules.
 317                         if ( $this->isFileModule( $name ) ) {
 318                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 319                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 320                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 321                                                 continue;
 322                                         }
 323
 324                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 325                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 326                                         if ( isset( $skinStyles[$name] ) ) {
 327                                                 $paths = (array)$skinStyles[$name];
 328                                                 $styleFiles = array();
 329                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 330                                                 $paths = (array)$skinStyles['+' . $name];
 331                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 332                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 333                                                         array();
 334                                         } else {
 335                                                 continue;
 336                                         }
 337
 338                                         // Add new file paths, remapping them to refer to our directories and not use settings
 339                                         // from the module we're modifying. These can come from the base definition or be defined
 340                                         // for each module.
 341                                         list( $localBasePath, $remoteBasePath ) =
 342                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 343                                         list( $localBasePath, $remoteBasePath ) =
 344                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 345
 346                                         foreach ( $paths as $path ) {
 347                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 348                                         }
 349
 350                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 351                                 }
 352                         }
 353                 }
 354
 355                 wfProfileOut( __METHOD__ );
 356         }
 357
 358         /**
 359          */
 360         public function registerTestModules() {
 361                 global $IP;
 362
 363                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 364                         throw new MWException( 'Attempt to register JavaScript test modules '
 365                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 366                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 367                 }
 368
 369                 wfProfileIn( __METHOD__ );
 370
 371                 // Get core test suites
 372                 $testModules = array();
 373                 $testModules['qunit'] = array();
 374                 // Get other test suites (e.g. from extensions)
 375                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 376
 377                 // Add the testrunner (which configures QUnit) to the dependencies.
 378                 // Since it must be ready before any of the test suites are executed.
 379                 foreach ( $testModules['qunit'] as &$module ) {
 380                         // Make sure all test modules are top-loading so that when QUnit starts
 381                         // on document-ready, it will run once and finish. If some tests arrive
 382                         // later (possibly after QUnit has already finished) they will be ignored.
 383                         $module['position'] = 'top';
 384                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 385                 }
 386
 387                 $testModules['qunit'] =
 388                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 389
 390                 foreach ( $testModules as $id => $names ) {
 391                         // Register test modules
 392                         $this->register( $testModules[$id] );
 393
 394                         // Keep track of their names so that they can be loaded together
 395                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 396                 }
 397
 398                 wfProfileOut( __METHOD__ );
 399         }
 400
 401         /**
 402          * Add a foreign source of modules.
 403          *
 404          * Source properties:
 405          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 406          *
 407          * @param mixed $id Source ID (string), or array( id1 => props1, id2 => props2, ... )
 408          * @param array $properties Source properties
 409          * @throws MWException
 410          */
 411         public function addSource( $id, $properties = null ) {
 412                 // Allow multiple sources to be registered in one call
 413                 if ( is_array( $id ) ) {
 414                         foreach ( $id as $key => $value ) {
 415                                 $this->addSource( $key, $value );
 416                         }
 417                         return;
 418                 }
 419
 420                 // Disallow duplicates
 421                 if ( isset( $this->sources[$id] ) ) {
 422                         throw new MWException(
 423                                 'ResourceLoader duplicate source addition error. ' .
 424                                 'Another source has already been registered as ' . $id
 425                         );
 426                 }
 427
 428                 // Validate properties
 429                 foreach ( self::$requiredSourceProperties as $prop ) {
 430                         if ( !isset( $properties[$prop] ) ) {
 431                                 throw new MWException( "Required property $prop missing from source ID $id" );
 432                         }
 433                 }
 434
 435                 $this->sources[$id] = $properties;
 436         }
 437
 438         /**
 439          * Get a list of module names.
 440          *
 441          * @return array List of module names
 442          */
 443         public function getModuleNames() {
 444                 return array_keys( $this->moduleInfos );
 445         }
 446
 447         /**
 448          * Get a list of test module names for one (or all) frameworks.
 449          *
 450          * If the given framework id is unknkown, or if the in-object variable is not an array,
 451          * then it will return an empty array.
 452          *
 453          * @param string $framework Get only the test module names for one
 454          *   particular framework (optional)
 455          * @return array
 456          */
 457         public function getTestModuleNames( $framework = 'all' ) {
 458                 /** @todo api siteinfo prop testmodulenames modulenames */
 459                 if ( $framework == 'all' ) {
 460                         return $this->testModuleNames;
 461                 } elseif ( isset( $this->testModuleNames[$framework] )
 462                         && is_array( $this->testModuleNames[$framework] )
 463                 ) {
 464                         return $this->testModuleNames[$framework];
 465                 } else {
 466                         return array();
 467                 }
 468         }
 469
 470         /**
 471          * Get the ResourceLoaderModule object for a given module name.
 472          *
 473          * If an array of module parameters exists but a ResourceLoaderModule object has not
 474          * yet been instantiated, this method will instantiate and cache that object such that
 475          * subsequent calls simply return the same object.
 476          *
 477          * @param string $name Module name
 478          * @return ResourceLoaderModule|null If module has been registered, return a
 479          *  ResourceLoaderModule instance. Otherwise, return null.
 480          */
 481         public function getModule( $name ) {
 482                 if ( !isset( $this->modules[$name] ) ) {
 483                         if ( !isset( $this->moduleInfos[$name] ) ) {
 484                                 // No such module
 485                                 return null;
 486                         }
 487                         // Construct the requested object
 488                         $info = $this->moduleInfos[$name];
 489                         /** @var ResourceLoaderModule $object */
 490                         if ( isset( $info['object'] ) ) {
 491                                 // Object given in info array
 492                                 $object = $info['object'];
 493                         } else {
 494                                 if ( !isset( $info['class'] ) ) {
 495                                         $class = 'ResourceLoaderFileModule';
 496                                 } else {
 497                                         $class = $info['class'];
 498                                 }
 499                                 /** @var ResourceLoaderModule $object */
 500                                 $object = new $class( $info );
 501                                 $object->setConfig( $this->getConfig() );
 502                         }
 503                         $object->setName( $name );
 504                         $this->modules[$name] = $object;
 505                 }
 506
 507                 return $this->modules[$name];
 508         }
 509
 510         /**
 511          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 512          *
 513          * @param string $name Module name
 514          * @return bool
 515          */
 516         protected function isFileModule( $name ) {
 517                 if ( !isset( $this->moduleInfos[$name] ) ) {
 518                         return false;
 519                 }
 520                 $info = $this->moduleInfos[$name];
 521                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 522                         return false;
 523                 }
 524                 return true;
 525         }
 526
 527         /**
 528          * Get the list of sources.
 529          *
 530          * @return array Like array( id => array of properties, .. )
 531          */
 532         public function getSources() {
 533                 return $this->sources;
 534         }
 535
 536         /**
 537          * Get the URL to the load.php endpoint for the given
 538          * ResourceLoader source
 539          *
 540          * @since 1.24
 541          * @param string $source
 542          * @throws MWException On an invalid $source name
 543          * @return string
 544          */
 545         public function getLoadScript( $source ) {
 546                 if ( !isset( $this->sources[$source] ) ) {
 547                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 548                 }
 549                 return $this->sources[$source]['loadScript'];
 550         }
 551
 552         /**
 553          * Output a response to a load request, including the content-type header.
 554          *
 555          * @param ResourceLoaderContext $context Context in which a response should be formed
 556          */
 557         public function respond( ResourceLoaderContext $context ) {
 558                 // Use file cache if enabled and available...
 559                 if ( $this->config->get( 'UseFileCache' ) ) {
 560                         $fileCache = ResourceFileCache::newFromContext( $context );
 561                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 562                                 return; // output handled
 563                         }
 564                 }
 565
 566                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 567                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 568                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 569                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 570                 // the whole thing in our own output buffer to be sure the active buffer
 571                 // doesn't use ob_gzhandler.
 572                 // See http://bugs.php.net/bug.php?id=36514
 573                 ob_start();
 574
 575                 wfProfileIn( __METHOD__ );
 576                 $errors = '';
 577
 578                 // Find out which modules are missing and instantiate the others
 579                 $modules = array();
 580                 $missing = array();
 581                 foreach ( $context->getModules() as $name ) {
 582                         $module = $this->getModule( $name );
 583                         if ( $module ) {
 584                                 // Do not allow private modules to be loaded from the web.
 585                                 // This is a security issue, see bug 34907.
 586                                 if ( $module->getGroup() === 'private' ) {
 587                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 588                                         $this->hasErrors = true;
 589                                         // Add exception to the output as a comment
 590                                         $errors .= self::makeComment( "Cannot show private module \"$name\"" );
 591
 592                                         continue;
 593                                 }
 594                                 $modules[$name] = $module;
 595                         } else {
 596                                 $missing[] = $name;
 597                         }
 598                 }
 599
 600                 // Preload information needed to the mtime calculation below
 601                 try {
 602                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 603                 } catch ( Exception $e ) {
 604                         MWExceptionHandler::logException( $e );
 605                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 606                         $this->hasErrors = true;
 607                         // Add exception to the output as a comment
 608                         $errors .= self::formatException( $e );
 609                 }
 610
 611                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 612
 613                 // To send Last-Modified and support If-Modified-Since, we need to detect
 614                 // the last modified time
 615                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 616                 foreach ( $modules as $module ) {
 617                         /**
 618                          * @var $module ResourceLoaderModule
 619                          */
 620                         try {
 621                                 // Calculate maximum modified time
 622                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 623                         } catch ( Exception $e ) {
 624                                 MWExceptionHandler::logException( $e );
 625                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 626                                 $this->hasErrors = true;
 627                                 // Add exception to the output as a comment
 628                                 $errors .= self::formatException( $e );
 629                         }
 630                 }
 631
 632                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 633
 634                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 635                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 636                         wfProfileOut( __METHOD__ );
 637                         return; // output handled (buffers cleared)
 638                 }
 639
 640                 // Generate a response
 641                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 642
 643                 // Prepend comments indicating exceptions
 644                 $response = $errors . $response;
 645
 646                 // Capture any PHP warnings from the output buffer and append them to the
 647                 // response in a comment if we're in debug mode.
 648                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 649                         $response = self::makeComment( $warnings ) . $response;
 650                         $this->hasErrors = true;
 651                 }
 652
 653                 // Save response to file cache unless there are errors
 654                 if ( isset( $fileCache ) && !$errors && !count( $missing ) ) {
 655                         // Cache single modules...and other requests if there are enough hits
 656                         if ( ResourceFileCache::useFileCache( $context ) ) {
 657                                 if ( $fileCache->isCacheWorthy() ) {
 658                                         $fileCache->saveText( $response );
 659                                 } else {
 660                                         $fileCache->incrMissesRecent( $context->getRequest() );
 661                                 }
 662                         }
 663                 }
 664
 665                 // Send content type and cache related headers
 666                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 667
 668                 // Remove the output buffer and output the response
 669                 ob_end_clean();
 670                 echo $response;
 671
 672                 wfProfileOut( __METHOD__ );
 673         }
 674
 675         /**
 676          * Send content type and last modified headers to the client.
 677          * @param ResourceLoaderContext $context
 678          * @param string $mtime TS_MW timestamp to use for last-modified
 679          * @param bool $errors Whether there are commented-out errors in the response
 680          * @return void
 681          */
 682         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 683                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 684                 // If a version wasn't specified we need a shorter expiry time for updates
 685                 // to propagate to clients quickly
 686                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 687                 if ( is_null( $context->getVersion() ) || $errors ) {
 688                         $maxage = $rlMaxage['unversioned']['client'];
 689                         $smaxage = $rlMaxage['unversioned']['server'];
 690                 // If a version was specified we can use a longer expiry time since changing
 691                 // version numbers causes cache misses
 692                 } else {
 693                         $maxage = $rlMaxage['versioned']['client'];
 694                         $smaxage = $rlMaxage['versioned']['server'];
 695                 }
 696                 if ( $context->getOnly() === 'styles' ) {
 697                         header( 'Content-Type: text/css; charset=utf-8' );
 698                         header( 'Access-Control-Allow-Origin: *' );
 699                 } else {
 700                         header( 'Content-Type: text/javascript; charset=utf-8' );
 701                 }
 702                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 703                 if ( $context->getDebug() ) {
 704                         // Do not cache debug responses
 705                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 706                         header( 'Pragma: no-cache' );
 707                 } else {
 708                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 709                         $exp = min( $maxage, $smaxage );
 710                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 711                 }
 712         }
 713
 714         /**
 715          * Respond with 304 Last Modified if appropiate.
 716          *
 717          * If there's an If-Modified-Since header, respond with a 304 appropriately
 718          * and clear out the output buffer. If the client cache is too old then do nothing.
 719          *
 720          * @param ResourceLoaderContext $context
 721          * @param string $mtime The TS_MW timestamp to check the header against
 722          * @return bool True if 304 header sent and output handled
 723          */
 724         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 725                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 726                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 727                 // so we get a valid timestamp.
 728                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 729                 // Never send 304s in debug mode
 730                 if ( $ims !== false && !$context->getDebug() ) {
 731                         $imsTS = strtok( $ims, ';' );
 732                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 733                                 // There's another bug in ob_gzhandler (see also the comment at
 734                                 // the top of this function) that causes it to gzip even empty
 735                                 // responses, meaning it's impossible to produce a truly empty
 736                                 // response (because the gzip header is always there). This is
 737                                 // a problem because 304 responses have to be completely empty
 738                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 739                                 // See also http://bugs.php.net/bug.php?id=51579
 740                                 // To work around this, we tear down all output buffering before
 741                                 // sending the 304.
 742                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 743
 744                                 header( 'HTTP/1.0 304 Not Modified' );
 745                                 header( 'Status: 304 Not Modified' );
 746                                 return true;
 747                         }
 748                 }
 749                 return false;
 750         }
 751
 752         /**
 753          * Send out code for a response from file cache if possible.
 754          *
 755          * @param ResourceFileCache $fileCache Cache object for this request URL
 756          * @param ResourceLoaderContext $context Context in which to generate a response
 757          * @return bool If this found a cache file and handled the response
 758          */
 759         protected function tryRespondFromFileCache(
 760                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 761         ) {
 762                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 763                 // Buffer output to catch warnings.
 764                 ob_start();
 765                 // Get the maximum age the cache can be
 766                 $maxage = is_null( $context->getVersion() )
 767                         ? $rlMaxage['unversioned']['server']
 768                         : $rlMaxage['versioned']['server'];
 769                 // Minimum timestamp the cache file must have
 770                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 771                 if ( !$good ) {
 772                         try { // RL always hits the DB on file cache miss...
 773                                 wfGetDB( DB_SLAVE );
 774                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 775                                 $good = $fileCache->isCacheGood(); // cache existence check
 776                         }
 777                 }
 778                 if ( $good ) {
 779                         $ts = $fileCache->cacheTimestamp();
 780                         // Send content type and cache headers
 781                         $this->sendResponseHeaders( $context, $ts, false );
 782                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 783                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 784                                 return false; // output handled (buffers cleared)
 785                         }
 786                         $response = $fileCache->fetchText();
 787                         // Capture any PHP warnings from the output buffer and append them to the
 788                         // response in a comment if we're in debug mode.
 789                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 790                                 $response = "/*\n$warnings\n*/\n" . $response;
 791                         }
 792                         // Remove the output buffer and output the response
 793                         ob_end_clean();
 794                         echo $response . "\n/* Cached {$ts} */";
 795                         return true; // cache hit
 796                 }
 797                 // Clear buffer
 798                 ob_end_clean();
 799
 800                 return false; // cache miss
 801         }
 802
 803         /**
 804          * Generate a CSS or JS comment block.
 805          *
 806          * Only use this for public data, not error message details.
 807          *
 808          * @param string $text
 809          * @return string
 810          */
 811         public static function makeComment( $text ) {
 812                 $encText = str_replace( '*/', '* /', $text );
 813                 return "/*\n$encText\n*/\n";
 814         }
 815
 816         /**
 817          * Handle exception display.
 818          *
 819          * @param Exception $e Exception to be shown to the user
 820          * @return string Sanitized text that can be returned to the user
 821          */
 822         public static function formatException( $e ) {
 823                 global $wgShowExceptionDetails;
 824
 825                 if ( $wgShowExceptionDetails ) {
 826                         return self::makeComment( $e->__toString() );
 827                 } else {
 828                         return self::makeComment( wfMessage( 'internalerror' )->text() );
 829                 }
 830         }
 831
 832         /**
 833          * Generate code for a response.
 834          *
 835          * @param ResourceLoaderContext $context Context in which to generate a response
 836          * @param array $modules List of module objects keyed by module name
 837          * @param array $missing List of requested module names that are unregistered (optional)
 838          * @return string Response data
 839          */
 840         public function makeModuleResponse( ResourceLoaderContext $context,
 841                 array $modules, array $missing = array()
 842         ) {
 843                 $out = '';
 844                 $exceptions = '';
 845                 $states = array();
 846
 847                 if ( !count( $modules ) && !count( $missing ) ) {
 848                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 849    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 850    no modules were requested. Max made me put this here. */";
 851                 }
 852
 853                 wfProfileIn( __METHOD__ );
 854
 855                 // Pre-fetch blobs
 856                 if ( $context->shouldIncludeMessages() ) {
 857                         try {
 858                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 859                         } catch ( Exception $e ) {
 860                                 MWExceptionHandler::logException( $e );
 861                                 wfDebugLog(
 862                                         'resourceloader',
 863                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 864                                 );
 865                                 $this->hasErrors = true;
 866                                 // Add exception to the output as a comment
 867                                 $exceptions .= self::formatException( $e );
 868                         }
 869                 } else {
 870                         $blobs = array();
 871                 }
 872
 873                 foreach ( $missing as $name ) {
 874                         $states[$name] = 'missing';
 875                 }
 876
 877                 // Generate output
 878                 $isRaw = false;
 879                 foreach ( $modules as $name => $module ) {
 880                         /**
 881                          * @var $module ResourceLoaderModule
 882                          */
 883
 884                         wfProfileIn( __METHOD__ . '-' . $name );
 885                         try {
 886                                 $scripts = '';
 887                                 if ( $context->shouldIncludeScripts() ) {
 888                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 889                                         // However, we can't do this if the module doesn't support it
 890                                         // We also can't do this if there is an only= parameter, because we have to give
 891                                         // the module a way to return a load.php URL without causing an infinite loop
 892                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 893                                                 $scripts = $module->getScriptURLsForDebug( $context );
 894                                         } else {
 895                                                 $scripts = $module->getScript( $context );
 896                                                 // rtrim() because there are usually a few line breaks
 897                                                 // after the last ';'. A new line at EOF, a new line
 898                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 899                                                 if ( is_string( $scripts )
 900                                                         && strlen( $scripts )
 901                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 902                                                 ) {
 903                                                         // Append semicolon to prevent weird bugs caused by files not
 904                                                         // terminating their statements right (bug 27054)
 905                                                         $scripts .= ";\n";
 906                                                 }
 907                                         }
 908                                 }
 909                                 // Styles
 910                                 $styles = array();
 911                                 if ( $context->shouldIncludeStyles() ) {
 912                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 913                                         // that don't *have* any stylesheets (bug 38024).
 914                                         $stylePairs = $module->getStyles( $context );
 915                                         if ( count( $stylePairs ) ) {
 916                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 917                                                 // See comment near shouldIncludeScripts() for more details
 918                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 919                                                         $styles = array(
 920                                                                 'url' => $module->getStyleURLsForDebug( $context )
 921                                                         );
 922                                                 } else {
 923                                                         // Minify CSS before embedding in mw.loader.implement call
 924                                                         // (unless in debug mode)
 925                                                         if ( !$context->getDebug() ) {
 926                                                                 foreach ( $stylePairs as $media => $style ) {
 927                                                                         // Can be either a string or an array of strings.
 928                                                                         if ( is_array( $style ) ) {
 929                                                                                 $stylePairs[$media] = array();
 930                                                                                 foreach ( $style as $cssText ) {
 931                                                                                         if ( is_string( $cssText ) ) {
 932                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 933                                                                                         }
 934                                                                                 }
 935                                                                         } elseif ( is_string( $style ) ) {
 936                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 937                                                                         }
 938                                                                 }
 939                                                         }
 940                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 941                                                         $styles = array(
 942                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 943                                                         );
 944                                                 }
 945                                         }
 946                                 }
 947
 948                                 // Messages
 949                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 950
 951                                 // Append output
 952                                 switch ( $context->getOnly() ) {
 953                                         case 'scripts':
 954                                                 if ( is_string( $scripts ) ) {
 955                                                         // Load scripts raw...
 956                                                         $out .= $scripts;
 957                                                 } elseif ( is_array( $scripts ) ) {
 958                                                         // ...except when $scripts is an array of URLs
 959                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 960                                                 }
 961                                                 break;
 962                                         case 'styles':
 963                                                 // We no longer seperate into media, they are all combined now with
 964                                                 // custom media type groups into @media .. {} sections as part of the css string.
 965                                                 // Module returns either an empty array or a numerical array with css strings.
 966                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 967                                                 break;
 968                                         case 'messages':
 969                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 970                                                 break;
 971                                         default:
 972                                                 $out .= self::makeLoaderImplementScript(
 973                                                         $name,
 974                                                         $scripts,
 975                                                         $styles,
 976                                                         new XmlJsCode( $messagesBlob )
 977                                                 );
 978                                                 break;
 979                                 }
 980                         } catch ( Exception $e ) {
 981                                 MWExceptionHandler::logException( $e );
 982                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
 983                                 $this->hasErrors = true;
 984                                 // Add exception to the output as a comment
 985                                 $exceptions .= self::formatException( $e );
 986
 987                                 // Respond to client with error-state instead of module implementation
 988                                 $states[$name] = 'error';
 989                                 unset( $modules[$name] );
 990                         }
 991                         $isRaw |= $module->isRaw();
 992                         wfProfileOut( __METHOD__ . '-' . $name );
 993                 }
 994
 995                 // Update module states
 996                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
 997                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
 998                                 // Set the state of modules loaded as only scripts to ready as
 999                                 // they don't have an mw.loader.implement wrapper that sets the state
1000                                 foreach ( $modules as $name => $module ) {
1001                                         $states[$name] = 'ready';
1002                                 }
1003                         }
1004
1005                         // Set the state of modules we didn't respond to with mw.loader.implement
1006                         if ( count( $states ) ) {
1007                                 $out .= self::makeLoaderStateScript( $states );
1008                         }
1009
1010                         if ( $context->getOnly() === 'scripts' ) {
1011                                 // In only=script requests for modules that are not raw (e.g. not the startup module)
1012                                 // ensure the execution is conditional to avoid situations where browsers with an
1013                                 // unsupported environment do unconditionally execute a module's scripts. Otherwise users
1014                                 // will get things like "ReferenceError: mw is undefined" or "jQuery is undefined" from
1015                                 // legacy scripts loaded with only=scripts (such as the 'site' module).
1016                                 $out = self::makeLoaderConditionalScript( $out );
1017                         }
1018                 } else {
1019                         if ( count( $states ) ) {
1020                                 $exceptions .= self::makeComment(
1021                                         'Problematic modules: ' . FormatJson::encode( $states, ResourceLoader::inDebugMode() )
1022                                 );
1023                         }
1024                 }
1025
1026                 if ( !$context->getDebug() ) {
1027                         if ( $context->getOnly() === 'styles' ) {
1028                                 $out = $this->filter( 'minify-css', $out );
1029                         } else {
1030                                 $out = $this->filter( 'minify-js', $out );
1031                         }
1032                 }
1033
1034                 wfProfileOut( __METHOD__ );
1035                 return $exceptions . $out;
1036         }
1037
1038         /* Static Methods */
1039
1040         /**
1041          * Return JS code that calls mw.loader.implement with given module properties.
1042          *
1043          * @param string $name Module name
1044          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1045          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1046          *   to CSS files keyed by media type
1047          * @param mixed $messages List of messages associated with this module. May either be an
1048          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1049          *   the same data, wrapped in an XmlJsCode object.
1050          * @throws MWException
1051          * @return string
1052          */
1053         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
1054                 if ( is_string( $scripts ) ) {
1055                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1056                 } elseif ( !is_array( $scripts ) ) {
1057                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1058                 }
1059                 return Xml::encodeJsCall(
1060                         'mw.loader.implement',
1061                         array(
1062                                 $name,
1063                                 $scripts,
1064                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1065                                 // Although these variables are associative arrays, which become javascript
1066                                 // objects through json_encode. In many cases they will be empty arrays, and
1067                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1068                                 // output javascript "[]" instead of "{}". This fixes that.
1069                                 (object)$styles,
1070                                 (object)$messages
1071                         ),
1072                         ResourceLoader::inDebugMode()
1073                 );
1074         }
1075
1076         /**
1077          * Returns JS code which, when called, will register a given list of messages.
1078          *
1079          * @param mixed $messages Either an associative array mapping message key to value, or a
1080          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1081          * @return string
1082          */
1083         public static function makeMessageSetScript( $messages ) {
1084                 return Xml::encodeJsCall(
1085                         'mw.messages.set',
1086                         array( (object)$messages ),
1087                         ResourceLoader::inDebugMode()
1088                 );
1089         }
1090
1091         /**
1092          * Combines an associative array mapping media type to CSS into a
1093          * single stylesheet with "@media" blocks.
1094          *
1095          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1096          * @return array
1097          */
1098         public static function makeCombinedStyles( array $stylePairs ) {
1099                 $out = array();
1100                 foreach ( $stylePairs as $media => $styles ) {
1101                         // ResourceLoaderFileModule::getStyle can return the styles
1102                         // as a string or an array of strings. This is to allow separation in
1103                         // the front-end.
1104                         $styles = (array)$styles;
1105                         foreach ( $styles as $style ) {
1106                                 $style = trim( $style );
1107                                 // Don't output an empty "@media print { }" block (bug 40498)
1108                                 if ( $style !== '' ) {
1109                                         // Transform the media type based on request params and config
1110                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1111                                         $media = OutputPage::transformCssMedia( $media );
1112
1113                                         if ( $media === '' || $media == 'all' ) {
1114                                                 $out[] = $style;
1115                                         } elseif ( is_string( $media ) ) {
1116                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1117                                         }
1118                                         // else: skip
1119                                 }
1120                         }
1121                 }
1122                 return $out;
1123         }
1124
1125         /**
1126          * Returns a JS call to mw.loader.state, which sets the state of a
1127          * module or modules to a given value. Has two calling conventions:
1128          *
1129          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1130          *         Set the state of a single module called $name to $state
1131          *
1132          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1133          *         Set the state of modules with the given names to the given states
1134          *
1135          * @param string $name
1136          * @param string $state
1137          * @return string
1138          */
1139         public static function makeLoaderStateScript( $name, $state = null ) {
1140                 if ( is_array( $name ) ) {
1141                         return Xml::encodeJsCall(
1142                                 'mw.loader.state',
1143                                 array( $name ),
1144                                 ResourceLoader::inDebugMode()
1145                         );
1146                 } else {
1147                         return Xml::encodeJsCall(
1148                                 'mw.loader.state',
1149                                 array( $name, $state ),
1150                                 ResourceLoader::inDebugMode()
1151                         );
1152                 }
1153         }
1154
1155         /**
1156          * Returns JS code which calls the script given by $script. The script will
1157          * be called with local variables name, version, dependencies and group,
1158          * which will have values corresponding to $name, $version, $dependencies
1159          * and $group as supplied.
1160          *
1161          * @param string $name Module name
1162          * @param int $version Module version number as a timestamp
1163          * @param array $dependencies List of module names on which this module depends
1164          * @param string $group Group which the module is in.
1165          * @param string $source Source of the module, or 'local' if not foreign.
1166          * @param string $script JavaScript code
1167          * @return string
1168          */
1169         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1170                 $group, $source, $script
1171         ) {
1172                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1173                 return Xml::encodeJsCall(
1174                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1175                         array( $name, $version, $dependencies, $group, $source ),
1176                         ResourceLoader::inDebugMode()
1177                 );
1178         }
1179
1180         /**
1181          * Returns JS code which calls mw.loader.register with the given
1182          * parameters. Has three calling conventions:
1183          *
1184          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1185          *        $dependencies, $group, $source, $skip
1186          *     ):
1187          *        Register a single module.
1188          *
1189          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1190          *        Register modules with the given names.
1191          *
1192          *   - ResourceLoader::makeLoaderRegisterScript( array(
1193          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1194          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1195          *        ...
1196          *     ) ):
1197          *        Registers modules with the given names and parameters.
1198          *
1199          * @param string $name Module name
1200          * @param int $version Module version number as a timestamp
1201          * @param array $dependencies List of module names on which this module depends
1202          * @param string $group Group which the module is in
1203          * @param string $source Source of the module, or 'local' if not foreign
1204          * @param string $skip Script body of the skip function
1205          * @return string
1206          */
1207         public static function makeLoaderRegisterScript( $name, $version = null,
1208                 $dependencies = null, $group = null, $source = null, $skip = null
1209         ) {
1210                 if ( is_array( $name ) ) {
1211                         return Xml::encodeJsCall(
1212                                 'mw.loader.register',
1213                                 array( $name ),
1214                                 ResourceLoader::inDebugMode()
1215                         );
1216                 } else {
1217                         $version = (int)$version > 1 ? (int)$version : 1;
1218                         return Xml::encodeJsCall(
1219                                 'mw.loader.register',
1220                                 array( $name, $version, $dependencies, $group, $source, $skip ),
1221                                 ResourceLoader::inDebugMode()
1222                         );
1223                 }
1224         }
1225
1226         /**
1227          * Returns JS code which calls mw.loader.addSource() with the given
1228          * parameters. Has two calling conventions:
1229          *
1230          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1231          *       Register a single source
1232          *
1233          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
1234          *       Register sources with the given IDs and properties.
1235          *
1236          * @param string $id Source ID
1237          * @param array $properties Source properties (see addSource())
1238          * @return string
1239          */
1240         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1241                 if ( is_array( $id ) ) {
1242                         return Xml::encodeJsCall(
1243                                 'mw.loader.addSource',
1244                                 array( $id ),
1245                                 ResourceLoader::inDebugMode()
1246                         );
1247                 } else {
1248                         return Xml::encodeJsCall(
1249                                 'mw.loader.addSource',
1250                                 array( $id, $properties ),
1251                                 ResourceLoader::inDebugMode()
1252                         );
1253                 }
1254         }
1255
1256         /**
1257          * Returns JS code which runs given JS code if the client-side framework is
1258          * present.
1259          *
1260          * @param string $script JavaScript code
1261          * @return string
1262          */
1263         public static function makeLoaderConditionalScript( $script ) {
1264                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1265         }
1266
1267         /**
1268          * Returns JS code which will set the MediaWiki configuration array to
1269          * the given value.
1270          *
1271          * @param array $configuration List of configuration values keyed by variable name
1272          * @return string
1273          */
1274         public static function makeConfigSetScript( array $configuration ) {
1275                 return Xml::encodeJsCall(
1276                         'mw.config.set',
1277                         array( $configuration ),
1278                         ResourceLoader::inDebugMode()
1279                 );
1280         }
1281
1282         /**
1283          * Convert an array of module names to a packed query string.
1284          *
1285          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1286          * becomes 'foo.bar,baz|bar.baz,quux'
1287          * @param array $modules List of module names (strings)
1288          * @return string Packed query string
1289          */
1290         public static function makePackedModulesString( $modules ) {
1291                 $groups = array(); // array( prefix => array( suffixes ) )
1292                 foreach ( $modules as $module ) {
1293                         $pos = strrpos( $module, '.' );
1294                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1295                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1296                         $groups[$prefix][] = $suffix;
1297                 }
1298
1299                 $arr = array();
1300                 foreach ( $groups as $prefix => $suffixes ) {
1301                         $p = $prefix === '' ? '' : $prefix . '.';
1302                         $arr[] = $p . implode( ',', $suffixes );
1303                 }
1304                 $str = implode( '|', $arr );
1305                 return $str;
1306         }
1307
1308         /**
1309          * Determine whether debug mode was requested
1310          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1311          * @return bool
1312          */
1313         public static function inDebugMode() {
1314                 if ( self::$debugMode === null ) {
1315                         global $wgRequest, $wgResourceLoaderDebug;
1316                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1317                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1318                         );
1319                 }
1320                 return self::$debugMode;
1321         }
1322
1323         /**
1324          * Reset static members used for caching.
1325          *
1326          * Global state and $wgRequest are evil, but we're using it right
1327          * now and sometimes we need to be able to force ResourceLoader to
1328          * re-evaluate the context because it has changed (e.g. in the test suite).
1329          */
1330         public static function clearCache() {
1331                 self::$debugMode = null;
1332         }
1333
1334         /**
1335          * Build a load.php URL
1336          *
1337          * @since 1.24
1338          * @param string $source Name of the ResourceLoader source
1339          * @param ResourceLoaderContext $context
1340          * @param array $extraQuery
1341          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1342          */
1343         public function createLoaderURL( $source, ResourceLoaderContext $context,
1344                 $extraQuery = array()
1345         ) {
1346                 $query = self::createLoaderQuery( $context, $extraQuery );
1347                 $script = $this->getLoadScript( $source );
1348
1349                 // Prevent the IE6 extension check from being triggered (bug 28840)
1350                 // by appending a character that's invalid in Windows extensions ('*')
1351                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1352         }
1353
1354         /**
1355          * Build a load.php URL
1356          * @deprecated since 1.24, use createLoaderURL instead
1357          * @param array $modules Array of module names (strings)
1358          * @param string $lang Language code
1359          * @param string $skin Skin name
1360          * @param string|null $user User name. If null, the &user= parameter is omitted
1361          * @param string|null $version Versioning timestamp
1362          * @param bool $debug Whether the request should be in debug mode
1363          * @param string|null $only &only= parameter
1364          * @param bool $printable Printable mode
1365          * @param bool $handheld Handheld mode
1366          * @param array $extraQuery Extra query parameters to add
1367          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1368          */
1369         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1370                 $version = null, $debug = false, $only = null, $printable = false,
1371                 $handheld = false, $extraQuery = array()
1372         ) {
1373                 global $wgLoadScript;
1374
1375                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1376                         $only, $printable, $handheld, $extraQuery
1377                 );
1378
1379                 // Prevent the IE6 extension check from being triggered (bug 28840)
1380                 // by appending a character that's invalid in Windows extensions ('*')
1381                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1382         }
1383
1384         /**
1385          * Helper for createLoaderURL()
1386          *
1387          * @since 1.24
1388          * @see makeLoaderQuery
1389          * @param ResourceLoaderContext $context
1390          * @param array $extraQuery
1391          * @return array
1392          */
1393         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1394                 return self::makeLoaderQuery(
1395                         $context->getModules(),
1396                         $context->getLanguage(),
1397                         $context->getSkin(),
1398                         $context->getUser(),
1399                         $context->getVersion(),
1400                         $context->getDebug(),
1401                         $context->getOnly(),
1402                         $context->getRequest()->getBool( 'printable' ),
1403                         $context->getRequest()->getBool( 'handheld' ),
1404                         $extraQuery
1405                 );
1406         }
1407
1408         /**
1409          * Build a query array (array representation of query string) for load.php. Helper
1410          * function for makeLoaderURL().
1411          *
1412          * @param array $modules
1413          * @param string $lang
1414          * @param string $skin
1415          * @param string $user
1416          * @param string $version
1417          * @param bool $debug
1418          * @param string $only
1419          * @param bool $printable
1420          * @param bool $handheld
1421          * @param array $extraQuery
1422          *
1423          * @return array
1424          */
1425         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1426                 $version = null, $debug = false, $only = null, $printable = false,
1427                 $handheld = false, $extraQuery = array()
1428         ) {
1429                 $query = array(
1430                         'modules' => self::makePackedModulesString( $modules ),
1431                         'lang' => $lang,
1432                         'skin' => $skin,
1433                         'debug' => $debug ? 'true' : 'false',
1434                 );
1435                 if ( $user !== null ) {
1436                         $query['user'] = $user;
1437                 }
1438                 if ( $version !== null ) {
1439                         $query['version'] = $version;
1440                 }
1441                 if ( $only !== null ) {
1442                         $query['only'] = $only;
1443                 }
1444                 if ( $printable ) {
1445                         $query['printable'] = 1;
1446                 }
1447                 if ( $handheld ) {
1448                         $query['handheld'] = 1;
1449                 }
1450                 $query += $extraQuery;
1451
1452                 // Make queries uniform in order
1453                 ksort( $query );
1454                 return $query;
1455         }
1456
1457         /**
1458          * Check a module name for validity.
1459          *
1460          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1461          * at most 255 bytes.
1462          *
1463          * @param string $moduleName Module name to check
1464          * @return bool Whether $moduleName is a valid module name
1465          */
1466         public static function isValidModuleName( $moduleName ) {
1467                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1468         }
1469
1470         /**
1471          * Returns LESS compiler set up for use with MediaWiki
1472          *
1473          * @param Config $config
1474          * @throws MWException
1475          * @since 1.22
1476          * @return lessc
1477          */
1478         public static function getLessCompiler( Config $config ) {
1479                 // When called from the installer, it is possible that a required PHP extension
1480                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1481                 // exception (caught by the installer) to prevent a fatal error later on.
1482                 if ( !function_exists( 'ctype_digit' ) ) {
1483                         throw new MWException( 'lessc requires the Ctype extension' );
1484                 }
1485
1486                 $less = new lessc();
1487                 $less->setPreserveComments( true );
1488                 $less->setVariables( self::getLessVars( $config ) );
1489                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1490                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1491                         $less->registerFunction( $name, $func );
1492                 }
1493                 return $less;
1494         }
1495
1496         /**
1497          * Get global LESS variables.
1498          *
1499          * @param Config $config
1500          * @since 1.22
1501          * @return array Map of variable names to string CSS values.
1502          */
1503         public static function getLessVars( Config $config ) {
1504                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1505                 // Sort by key to ensure consistent hashing for cache lookups.
1506                 ksort( $lessVars );
1507                 return $lessVars;
1508         }
1509 }