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         /**
  39          * Module name/ResourceLoaderModule object pairs
  40          * @var array
  41          */
  42         protected $modules = array();
  43
  44         /**
  45          * Associative array mapping module name to info associative array
  46          * @var array
  47          */
  48         protected $moduleInfos = array();
  49
  50         /** @var Config $config */
  51         private $config;
  52
  53         /**
  54          * Associative array mapping framework ids to a list of names of test suite modules
  55          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  56          * @var array
  57          */
  58         protected $testModuleNames = array();
  59
  60         /**
  61          * E.g. array( 'source-id' => 'http://.../load.php' )
  62          * @var array
  63          */
  64         protected $sources = array();
  65
  66         /**
  67          * Errors accumulated during current respond() call.
  68          * @var array
  69          */
  70         protected $errors = array();
  71
  72         /**
  73          * Load information stored in the database about modules.
  74          *
  75          * This method grabs modules dependencies from the database and updates modules
  76          * objects.
  77          *
  78          * This is not inside the module code because it is much faster to
  79          * request all of the information at once than it is to have each module
  80          * requests its own information. This sacrifice of modularity yields a substantial
  81          * performance improvement.
  82          *
  83          * @param array $modules List of module names to preload information for
  84          * @param ResourceLoaderContext $context Context to load the information within
  85          */
  86         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  87                 if ( !count( $modules ) ) {
  88                         // Or else Database*::select() will explode, plus it's cheaper!
  89                         return;
  90                 }
  91                 $dbr = wfGetDB( DB_SLAVE );
  92                 $skin = $context->getSkin();
  93                 $lang = $context->getLanguage();
  94
  95                 // Get file dependency information
  96                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  97                                 'md_module' => $modules,
  98                                 'md_skin' => $skin
  99                         ), __METHOD__
 100                 );
 101
 102                 // Set modules' dependencies
 103                 $modulesWithDeps = array();
 104                 foreach ( $res as $row ) {
 105                         $module = $this->getModule( $row->md_module );
 106                         if ( $module ) {
 107                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 108                                 $modulesWithDeps[] = $row->md_module;
 109                         }
 110                 }
 111
 112                 // Register the absence of a dependency row too
 113                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 114                         $module = $this->getModule( $name );
 115                         if ( $module ) {
 116                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 117                         }
 118                 }
 119
 120                 // Get message blob mtimes. Only do this for modules with messages
 121                 $modulesWithMessages = array();
 122                 foreach ( $modules as $name ) {
 123                         $module = $this->getModule( $name );
 124                         if ( $module && count( $module->getMessages() ) ) {
 125                                 $modulesWithMessages[] = $name;
 126                         }
 127                 }
 128                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 129                 if ( count( $modulesWithMessages ) ) {
 130                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 131                                         'mr_resource' => $modulesWithMessages,
 132                                         'mr_lang' => $lang
 133                                 ), __METHOD__
 134                         );
 135                         foreach ( $res as $row ) {
 136                                 $module = $this->getModule( $row->mr_resource );
 137                                 if ( $module ) {
 138                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 139                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 140                                 }
 141                         }
 142                 }
 143                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 144                         $module = $this->getModule( $name );
 145                         if ( $module ) {
 146                                 $module->setMsgBlobMtime( $lang, 1 );
 147                         }
 148                 }
 149         }
 150
 151         /**
 152          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 153          *
 154          * Available filters are:
 155          *
 156          *    - minify-js \see JavaScriptMinifier::minify
 157          *    - minify-css \see CSSMin::minify
 158          *
 159          * If $data is empty, only contains whitespace or the filter was unknown,
 160          * $data is returned unmodified.
 161          *
 162          * @param string $filter Name of filter to run
 163          * @param string $data Text to filter, such as JavaScript or CSS text
 164          * @param string $cacheReport Whether to include the cache key report
 165          * @return string Filtered data, or a comment containing an error message
 166          */
 167         public function filter( $filter, $data, $cacheReport = true ) {
 168
 169                 // For empty/whitespace-only data or for unknown filters, don't perform
 170                 // any caching or processing
 171                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 172                         return $data;
 173                 }
 174
 175                 // Try for cache hit
 176                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 177                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 178                 $cache = wfGetCache( CACHE_ANYTHING );
 179                 $cacheEntry = $cache->get( $key );
 180                 if ( is_string( $cacheEntry ) ) {
 181                         wfIncrStats( "rl-$filter-cache-hits" );
 182                         return $cacheEntry;
 183                 }
 184
 185                 $result = '';
 186                 // Run the filter - we've already verified one of these will work
 187                 try {
 188                         wfIncrStats( "rl-$filter-cache-misses" );
 189                         switch ( $filter ) {
 190                                 case 'minify-js':
 191                                         $result = JavaScriptMinifier::minify( $data,
 192                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 193                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 194                                         );
 195                                         if ( $cacheReport ) {
 196                                                 $result .= "\n/* cache key: $key */";
 197                                         }
 198                                         break;
 199                                 case 'minify-css':
 200                                         $result = CSSMin::minify( $data );
 201                                         if ( $cacheReport ) {
 202                                                 $result .= "\n/* cache key: $key */";
 203                                         }
 204                                         break;
 205                         }
 206
 207                         // Save filtered text to Memcached
 208                         $cache->set( $key, $result );
 209                 } catch ( Exception $e ) {
 210                         MWExceptionHandler::logException( $e );
 211                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 212                         $this->errors[] = self::formatExceptionNoComment( $e );
 213                 }
 214
 215
 216                 return $result;
 217         }
 218
 219         /* Methods */
 220
 221         /**
 222          * Register core modules and runs registration hooks.
 223          * @param Config|null $config
 224          */
 225         public function __construct( Config $config = null ) {
 226                 global $IP;
 227
 228
 229                 if ( $config === null ) {
 230                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 231                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 232                 }
 233
 234                 $this->config = $config;
 235
 236                 // Add 'local' source first
 237                 $this->addSource( 'local', wfScript( 'load' ) );
 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                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 246                 $this->register( $config->get( 'ResourceModules' ) );
 247
 248                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 249                         $this->registerTestModules();
 250                 }
 251
 252         }
 253
 254         /**
 255          * @return Config
 256          */
 257         public function getConfig() {
 258                 return $this->config;
 259         }
 260
 261         /**
 262          * Register a module with the ResourceLoader system.
 263          *
 264          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 265          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 266          *   this may also be a ResourceLoaderModule object. Optional when using
 267          *   multiple-registration calling style.
 268          * @throws MWException If a duplicate module registration is attempted
 269          * @throws MWException If a module name contains illegal characters (pipes or commas)
 270          * @throws MWException If something other than a ResourceLoaderModule is being registered
 271          * @return bool False if there were any errors, in which case one or more modules were
 272          *   not registered
 273          */
 274         public function register( $name, $info = null ) {
 275
 276                 // Allow multiple modules to be registered in one call
 277                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 278                 foreach ( $registrations as $name => $info ) {
 279                         // Disallow duplicate registrations
 280                         if ( isset( $this->moduleInfos[$name] ) ) {
 281                                 // A module has already been registered by this name
 282                                 throw new MWException(
 283                                         'ResourceLoader duplicate registration error. ' .
 284                                         'Another module has already been registered as ' . $name
 285                                 );
 286                         }
 287
 288                         // Check $name for validity
 289                         if ( !self::isValidModuleName( $name ) ) {
 290                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 291                                         . "see ResourceLoader::isValidModuleName()" );
 292                         }
 293
 294                         // Attach module
 295                         if ( $info instanceof ResourceLoaderModule ) {
 296                                 $this->moduleInfos[$name] = array( 'object' => $info );
 297                                 $info->setName( $name );
 298                                 $this->modules[$name] = $info;
 299                         } elseif ( is_array( $info ) ) {
 300                                 // New calling convention
 301                                 $this->moduleInfos[$name] = $info;
 302                         } else {
 303                                 throw new MWException(
 304                                         'ResourceLoader module info type error for module \'' . $name .
 305                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 306                                 );
 307                         }
 308
 309                         // Last-minute changes
 310
 311                         // Apply custom skin-defined styles to existing modules.
 312                         if ( $this->isFileModule( $name ) ) {
 313                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 314                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 315                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 316                                                 continue;
 317                                         }
 318
 319                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 320                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 321                                         if ( isset( $skinStyles[$name] ) ) {
 322                                                 $paths = (array)$skinStyles[$name];
 323                                                 $styleFiles = array();
 324                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 325                                                 $paths = (array)$skinStyles['+' . $name];
 326                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 327                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 328                                                         array();
 329                                         } else {
 330                                                 continue;
 331                                         }
 332
 333                                         // Add new file paths, remapping them to refer to our directories and not use settings
 334                                         // from the module we're modifying. These can come from the base definition or be defined
 335                                         // for each module.
 336                                         list( $localBasePath, $remoteBasePath ) =
 337                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 338                                         list( $localBasePath, $remoteBasePath ) =
 339                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 340
 341                                         foreach ( $paths as $path ) {
 342                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 343                                         }
 344
 345                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 346                                 }
 347                         }
 348                 }
 349
 350         }
 351
 352         /**
 353          */
 354         public function registerTestModules() {
 355                 global $IP;
 356
 357                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 358                         throw new MWException( 'Attempt to register JavaScript test modules '
 359                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 360                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 361                 }
 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
 570                 // Find out which modules are missing and instantiate the others
 571                 $modules = array();
 572                 $missing = array();
 573                 foreach ( $context->getModules() as $name ) {
 574                         $module = $this->getModule( $name );
 575                         if ( $module ) {
 576                                 // Do not allow private modules to be loaded from the web.
 577                                 // This is a security issue, see bug 34907.
 578                                 if ( $module->getGroup() === 'private' ) {
 579                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 580                                         $this->errors[] = "Cannot show private module \"$name\"";
 581                                         continue;
 582                                 }
 583                                 $modules[$name] = $module;
 584                         } else {
 585                                 $missing[] = $name;
 586                         }
 587                 }
 588
 589                 // Preload information needed to the mtime calculation below
 590                 try {
 591                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 592                 } catch ( Exception $e ) {
 593                         MWExceptionHandler::logException( $e );
 594                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 595                         $this->errors[] = self::formatExceptionNoComment( $e );
 596                 }
 597
 598                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 599
 600                 // To send Last-Modified and support If-Modified-Since, we need to detect
 601                 // the last modified time
 602                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 603                 foreach ( $modules as $module ) {
 604                         /**
 605                          * @var $module ResourceLoaderModule
 606                          */
 607                         try {
 608                                 // Calculate maximum modified time
 609                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 610                         } catch ( Exception $e ) {
 611                                 MWExceptionHandler::logException( $e );
 612                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 613                                 $this->errors[] = self::formatExceptionNoComment( $e );
 614                         }
 615                 }
 616
 617                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 618
 619                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 620                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 621                         return; // output handled (buffers cleared)
 622                 }
 623
 624                 // Generate a response
 625                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 626
 627                 // Capture any PHP warnings from the output buffer and append them to the
 628                 // error list if we're in debug mode.
 629                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 630                         $this->errors[] = $warnings;
 631                 }
 632
 633                 // Save response to file cache unless there are errors
 634                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 635                         // Cache single modules and images...and other requests if there are enough hits
 636                         if ( ResourceFileCache::useFileCache( $context ) ) {
 637                                 if ( $fileCache->isCacheWorthy() ) {
 638                                         $fileCache->saveText( $response );
 639                                 } else {
 640                                         $fileCache->incrMissesRecent( $context->getRequest() );
 641                                 }
 642                         }
 643                 }
 644
 645                 // Send content type and cache related headers
 646                 $this->sendResponseHeaders( $context, $mtime, (bool)$this->errors );
 647
 648                 // Remove the output buffer and output the response
 649                 ob_end_clean();
 650
 651                 if ( $context->getImageObj() && $this->errors ) {
 652                         // We can't show both the error messages and the response when it's an image.
 653                         $errorText = '';
 654                         foreach ( $this->errors as $error ) {
 655                                 $errorText .= $error . "\n";
 656                         }
 657                         $response = $errorText;
 658                 } elseif ( $this->errors ) {
 659                         // Prepend comments indicating errors
 660                         $errorText = '';
 661                         foreach ( $this->errors as $error ) {
 662                                 $errorText .= self::makeComment( $error );
 663                         }
 664                         $response = $errorText . $response;
 665                 }
 666
 667                 $this->errors = array();
 668                 echo $response;
 669
 670         }
 671
 672         /**
 673          * Send content type and last modified headers to the client.
 674          * @param ResourceLoaderContext $context
 675          * @param string $mtime TS_MW timestamp to use for last-modified
 676          * @param bool $errors Whether there are errors in the response
 677          * @return void
 678          */
 679         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 680                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 681                 // If a version wasn't specified we need a shorter expiry time for updates
 682                 // to propagate to clients quickly
 683                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 684                 if ( is_null( $context->getVersion() ) || $errors ) {
 685                         $maxage = $rlMaxage['unversioned']['client'];
 686                         $smaxage = $rlMaxage['unversioned']['server'];
 687                 // If a version was specified we can use a longer expiry time since changing
 688                 // version numbers causes cache misses
 689                 } else {
 690                         $maxage = $rlMaxage['versioned']['client'];
 691                         $smaxage = $rlMaxage['versioned']['server'];
 692                 }
 693                 if ( $context->getImageObj() ) {
 694                         // Output different headers if we're outputting textual errors.
 695                         if ( $errors ) {
 696                                 header( 'Content-Type: text/plain; charset=utf-8' );
 697                         } else {
 698                                 $context->getImageObj()->sendResponseHeaders( $context );
 699                         }
 700                 } elseif ( $context->getOnly() === 'styles' ) {
 701                         header( 'Content-Type: text/css; charset=utf-8' );
 702                         header( 'Access-Control-Allow-Origin: *' );
 703                 } else {
 704                         header( 'Content-Type: text/javascript; charset=utf-8' );
 705                 }
 706                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 707                 if ( $context->getDebug() ) {
 708                         // Do not cache debug responses
 709                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 710                         header( 'Pragma: no-cache' );
 711                 } else {
 712                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 713                         $exp = min( $maxage, $smaxage );
 714                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 715                 }
 716         }
 717
 718         /**
 719          * Respond with 304 Last Modified if appropiate.
 720          *
 721          * If there's an If-Modified-Since header, respond with a 304 appropriately
 722          * and clear out the output buffer. If the client cache is too old then do nothing.
 723          *
 724          * @param ResourceLoaderContext $context
 725          * @param string $mtime The TS_MW timestamp to check the header against
 726          * @return bool True if 304 header sent and output handled
 727          */
 728         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 729                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 730                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 731                 // so we get a valid timestamp.
 732                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 733                 // Never send 304s in debug mode
 734                 if ( $ims !== false && !$context->getDebug() ) {
 735                         $imsTS = strtok( $ims, ';' );
 736                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 737                                 // There's another bug in ob_gzhandler (see also the comment at
 738                                 // the top of this function) that causes it to gzip even empty
 739                                 // responses, meaning it's impossible to produce a truly empty
 740                                 // response (because the gzip header is always there). This is
 741                                 // a problem because 304 responses have to be completely empty
 742                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 743                                 // See also http://bugs.php.net/bug.php?id=51579
 744                                 // To work around this, we tear down all output buffering before
 745                                 // sending the 304.
 746                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 747
 748                                 header( 'HTTP/1.0 304 Not Modified' );
 749                                 header( 'Status: 304 Not Modified' );
 750                                 return true;
 751                         }
 752                 }
 753                 return false;
 754         }
 755
 756         /**
 757          * Send out code for a response from file cache if possible.
 758          *
 759          * @param ResourceFileCache $fileCache Cache object for this request URL
 760          * @param ResourceLoaderContext $context Context in which to generate a response
 761          * @return bool If this found a cache file and handled the response
 762          */
 763         protected function tryRespondFromFileCache(
 764                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 765         ) {
 766                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 767                 // Buffer output to catch warnings.
 768                 ob_start();
 769                 // Get the maximum age the cache can be
 770                 $maxage = is_null( $context->getVersion() )
 771                         ? $rlMaxage['unversioned']['server']
 772                         : $rlMaxage['versioned']['server'];
 773                 // Minimum timestamp the cache file must have
 774                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 775                 if ( !$good ) {
 776                         try { // RL always hits the DB on file cache miss...
 777                                 wfGetDB( DB_SLAVE );
 778                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 779                                 $good = $fileCache->isCacheGood(); // cache existence check
 780                         }
 781                 }
 782                 if ( $good ) {
 783                         $ts = $fileCache->cacheTimestamp();
 784                         // Send content type and cache headers
 785                         $this->sendResponseHeaders( $context, $ts, false );
 786                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 787                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 788                                 return false; // output handled (buffers cleared)
 789                         }
 790                         $response = $fileCache->fetchText();
 791                         // Capture any PHP warnings from the output buffer and append them to the
 792                         // response in a comment if we're in debug mode.
 793                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 794                                 $response = "/*\n$warnings\n*/\n" . $response;
 795                         }
 796                         // Remove the output buffer and output the response
 797                         ob_end_clean();
 798                         echo $response . "\n/* Cached {$ts} */";
 799                         return true; // cache hit
 800                 }
 801                 // Clear buffer
 802                 ob_end_clean();
 803
 804                 return false; // cache miss
 805         }
 806
 807         /**
 808          * Generate a CSS or JS comment block.
 809          *
 810          * Only use this for public data, not error message details.
 811          *
 812          * @param string $text
 813          * @return string
 814          */
 815         public static function makeComment( $text ) {
 816                 $encText = str_replace( '*/', '* /', $text );
 817                 return "/*\n$encText\n*/\n";
 818         }
 819
 820         /**
 821          * Handle exception display.
 822          *
 823          * @param Exception $e Exception to be shown to the user
 824          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 825          */
 826         public static function formatException( $e ) {
 827                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 828         }
 829
 830         /**
 831          * Handle exception display.
 832          *
 833          * @since 1.25
 834          * @param Exception $e Exception to be shown to the user
 835          * @return string Sanitized text that can be returned to the user
 836          */
 837         protected static function formatExceptionNoComment( $e ) {
 838                 global $wgShowExceptionDetails;
 839
 840                 if ( $wgShowExceptionDetails ) {
 841                         return $e->__toString();
 842                 } else {
 843                         return wfMessage( 'internalerror' )->text();
 844                 }
 845         }
 846
 847         /**
 848          * Generate code for a response.
 849          *
 850          * @param ResourceLoaderContext $context Context in which to generate a response
 851          * @param array $modules List of module objects keyed by module name
 852          * @param array $missing List of requested module names that are unregistered (optional)
 853          * @return string Response data
 854          */
 855         public function makeModuleResponse( ResourceLoaderContext $context,
 856                 array $modules, array $missing = array()
 857         ) {
 858                 $out = '';
 859                 $states = array();
 860
 861                 if ( !count( $modules ) && !count( $missing ) ) {
 862                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 863    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 864    no modules were requested. Max made me put this here. */";
 865                 }
 866
 867
 868                 $image = $context->getImageObj();
 869                 if ( $image ) {
 870                         $data = $image->getImageData( $context );
 871                         if ( $data === false ) {
 872                                 $data = '';
 873                                 $this->errors[] = 'Image generation failed';
 874                         }
 875                         return $data;
 876                 }
 877
 878                 // Pre-fetch blobs
 879                 if ( $context->shouldIncludeMessages() ) {
 880                         try {
 881                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 882                         } catch ( Exception $e ) {
 883                                 MWExceptionHandler::logException( $e );
 884                                 wfDebugLog(
 885                                         'resourceloader',
 886                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 887                                 );
 888                                 $this->errors[] = self::formatExceptionNoComment( $e );
 889                         }
 890                 } else {
 891                         $blobs = array();
 892                 }
 893
 894                 foreach ( $missing as $name ) {
 895                         $states[$name] = 'missing';
 896                 }
 897
 898                 // Generate output
 899                 $isRaw = false;
 900                 foreach ( $modules as $name => $module ) {
 901                         /**
 902                          * @var $module ResourceLoaderModule
 903                          */
 904
 905                         wfProfileIn( __METHOD__ . '-' . $name );
 906                         try {
 907                                 $scripts = '';
 908                                 if ( $context->shouldIncludeScripts() ) {
 909                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 910                                         // However, we can't do this if the module doesn't support it
 911                                         // We also can't do this if there is an only= parameter, because we have to give
 912                                         // the module a way to return a load.php URL without causing an infinite loop
 913                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 914                                                 $scripts = $module->getScriptURLsForDebug( $context );
 915                                         } else {
 916                                                 $scripts = $module->getScript( $context );
 917                                                 // rtrim() because there are usually a few line breaks
 918                                                 // after the last ';'. A new line at EOF, a new line
 919                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 920                                                 if ( is_string( $scripts )
 921                                                         && strlen( $scripts )
 922                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 923                                                 ) {
 924                                                         // Append semicolon to prevent weird bugs caused by files not
 925                                                         // terminating their statements right (bug 27054)
 926                                                         $scripts .= ";\n";
 927                                                 }
 928                                         }
 929                                 }
 930                                 // Styles
 931                                 $styles = array();
 932                                 if ( $context->shouldIncludeStyles() ) {
 933                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 934                                         // that don't *have* any stylesheets (bug 38024).
 935                                         $stylePairs = $module->getStyles( $context );
 936                                         if ( count( $stylePairs ) ) {
 937                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 938                                                 // See comment near shouldIncludeScripts() for more details
 939                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 940                                                         $styles = array(
 941                                                                 'url' => $module->getStyleURLsForDebug( $context )
 942                                                         );
 943                                                 } else {
 944                                                         // Minify CSS before embedding in mw.loader.implement call
 945                                                         // (unless in debug mode)
 946                                                         if ( !$context->getDebug() ) {
 947                                                                 foreach ( $stylePairs as $media => $style ) {
 948                                                                         // Can be either a string or an array of strings.
 949                                                                         if ( is_array( $style ) ) {
 950                                                                                 $stylePairs[$media] = array();
 951                                                                                 foreach ( $style as $cssText ) {
 952                                                                                         if ( is_string( $cssText ) ) {
 953                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 954                                                                                         }
 955                                                                                 }
 956                                                                         } elseif ( is_string( $style ) ) {
 957                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 958                                                                         }
 959                                                                 }
 960                                                         }
 961                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 962                                                         $styles = array(
 963                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 964                                                         );
 965                                                 }
 966                                         }
 967                                 }
 968
 969                                 // Messages
 970                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 971
 972                                 // Append output
 973                                 switch ( $context->getOnly() ) {
 974                                         case 'scripts':
 975                                                 if ( is_string( $scripts ) ) {
 976                                                         // Load scripts raw...
 977                                                         $out .= $scripts;
 978                                                 } elseif ( is_array( $scripts ) ) {
 979                                                         // ...except when $scripts is an array of URLs
 980                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 981                                                 }
 982                                                 break;
 983                                         case 'styles':
 984                                                 // We no longer seperate into media, they are all combined now with
 985                                                 // custom media type groups into @media .. {} sections as part of the css string.
 986                                                 // Module returns either an empty array or a numerical array with css strings.
 987                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 988                                                 break;
 989                                         case 'messages':
 990                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 991                                                 break;
 992                                         case 'templates':
 993                                                 $out .= Xml::encodeJsCall(
 994                                                         'mw.templates.set',
 995                                                         array( $name, (object)$module->getTemplates() ),
 996                                                         ResourceLoader::inDebugMode()
 997                                                 );
 998                                                 break;
 999                                         default:
1000                                                 $out .= self::makeLoaderImplementScript(
1001                                                         $name,
1002                                                         $scripts,
1003                                                         $styles,
1004                                                         new XmlJsCode( $messagesBlob ),
1005                                                         $module->getTemplates()
1006                                                 );
1007                                                 break;
1008                                 }
1009                         } catch ( Exception $e ) {
1010                                 MWExceptionHandler::logException( $e );
1011                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1012                                 $this->errors[] = self::formatExceptionNoComment( $e );
1013
1014                                 // Respond to client with error-state instead of module implementation
1015                                 $states[$name] = 'error';
1016                                 unset( $modules[$name] );
1017                         }
1018                         $isRaw |= $module->isRaw();
1019                         wfProfileOut( __METHOD__ . '-' . $name );
1020                 }
1021
1022                 // Update module states
1023                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1024                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1025                                 // Set the state of modules loaded as only scripts to ready as
1026                                 // they don't have an mw.loader.implement wrapper that sets the state
1027                                 foreach ( $modules as $name => $module ) {
1028                                         $states[$name] = 'ready';
1029                                 }
1030                         }
1031
1032                         // Set the state of modules we didn't respond to with mw.loader.implement
1033                         if ( count( $states ) ) {
1034                                 $out .= self::makeLoaderStateScript( $states );
1035                         }
1036                 } else {
1037                         if ( count( $states ) ) {
1038                                 $this->errors[] = 'Problematic modules: ' .
1039                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1040                         }
1041                 }
1042
1043                 if ( !$context->getDebug() ) {
1044                         if ( $context->getOnly() === 'styles' ) {
1045                                 $out = $this->filter( 'minify-css', $out );
1046                         } else {
1047                                 $out = $this->filter( 'minify-js', $out );
1048                         }
1049                 }
1050
1051                 return $out;
1052         }
1053
1054         /* Static Methods */
1055
1056         /**
1057          * Return JS code that calls mw.loader.implement with given module properties.
1058          *
1059          * @param string $name Module name
1060          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1061          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1062          *   to CSS files keyed by media type
1063          * @param mixed $messages List of messages associated with this module. May either be an
1064          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1065          *   the same data, wrapped in an XmlJsCode object.
1066          * @param array $templates Keys are name of templates and values are the source of
1067          *   the template.
1068          * @throws MWException
1069          * @return string
1070          */
1071         public static function makeLoaderImplementScript( $name, $scripts, $styles,
1072                 $messages, $templates
1073         ) {
1074                 if ( is_string( $scripts ) ) {
1075                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1076                 } elseif ( !is_array( $scripts ) ) {
1077                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1078                 }
1079
1080                 return Xml::encodeJsCall(
1081                         'mw.loader.implement',
1082                         array(
1083                                 $name,
1084                                 $scripts,
1085                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1086                                 // Although these variables are associative arrays, which become javascript
1087                                 // objects through json_encode. In many cases they will be empty arrays, and
1088                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1089                                 // output javascript "[]" instead of "{}". This fixes that.
1090                                 (object)$styles,
1091                                 (object)$messages,
1092                                 (object)$templates,
1093                         ),
1094                         ResourceLoader::inDebugMode()
1095                 );
1096         }
1097
1098         /**
1099          * Returns JS code which, when called, will register a given list of messages.
1100          *
1101          * @param mixed $messages Either an associative array mapping message key to value, or a
1102          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1103          * @return string
1104          */
1105         public static function makeMessageSetScript( $messages ) {
1106                 return Xml::encodeJsCall(
1107                         'mw.messages.set',
1108                         array( (object)$messages ),
1109                         ResourceLoader::inDebugMode()
1110                 );
1111         }
1112
1113         /**
1114          * Combines an associative array mapping media type to CSS into a
1115          * single stylesheet with "@media" blocks.
1116          *
1117          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1118          * @return array
1119          */
1120         public static function makeCombinedStyles( array $stylePairs ) {
1121                 $out = array();
1122                 foreach ( $stylePairs as $media => $styles ) {
1123                         // ResourceLoaderFileModule::getStyle can return the styles
1124                         // as a string or an array of strings. This is to allow separation in
1125                         // the front-end.
1126                         $styles = (array)$styles;
1127                         foreach ( $styles as $style ) {
1128                                 $style = trim( $style );
1129                                 // Don't output an empty "@media print { }" block (bug 40498)
1130                                 if ( $style !== '' ) {
1131                                         // Transform the media type based on request params and config
1132                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1133                                         $media = OutputPage::transformCssMedia( $media );
1134
1135                                         if ( $media === '' || $media == 'all' ) {
1136                                                 $out[] = $style;
1137                                         } elseif ( is_string( $media ) ) {
1138                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1139                                         }
1140                                         // else: skip
1141                                 }
1142                         }
1143                 }
1144                 return $out;
1145         }
1146
1147         /**
1148          * Returns a JS call to mw.loader.state, which sets the state of a
1149          * module or modules to a given value. Has two calling conventions:
1150          *
1151          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1152          *         Set the state of a single module called $name to $state
1153          *
1154          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1155          *         Set the state of modules with the given names to the given states
1156          *
1157          * @param string $name
1158          * @param string $state
1159          * @return string
1160          */
1161         public static function makeLoaderStateScript( $name, $state = null ) {
1162                 if ( is_array( $name ) ) {
1163                         return Xml::encodeJsCall(
1164                                 'mw.loader.state',
1165                                 array( $name ),
1166                                 ResourceLoader::inDebugMode()
1167                         );
1168                 } else {
1169                         return Xml::encodeJsCall(
1170                                 'mw.loader.state',
1171                                 array( $name, $state ),
1172                                 ResourceLoader::inDebugMode()
1173                         );
1174                 }
1175         }
1176
1177         /**
1178          * Returns JS code which calls the script given by $script. The script will
1179          * be called with local variables name, version, dependencies and group,
1180          * which will have values corresponding to $name, $version, $dependencies
1181          * and $group as supplied.
1182          *
1183          * @param string $name Module name
1184          * @param int $version Module version number as a timestamp
1185          * @param array $dependencies List of module names on which this module depends
1186          * @param string $group Group which the module is in.
1187          * @param string $source Source of the module, or 'local' if not foreign.
1188          * @param string $script JavaScript code
1189          * @return string
1190          */
1191         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1192                 $group, $source, $script
1193         ) {
1194                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1195                 return Xml::encodeJsCall(
1196                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1197                         array( $name, $version, $dependencies, $group, $source ),
1198                         ResourceLoader::inDebugMode()
1199                 );
1200         }
1201
1202         /**
1203          * Remove empty values from the end of an array.
1204          *
1205          * Values considered empty:
1206          *
1207          * - null
1208          * - empty array
1209          *
1210          * @param Array $array
1211          */
1212         private static function trimArray( Array &$array ) {
1213                 $i = count( $array );
1214                 while ( $i-- ) {
1215                         if ( $array[$i] === null || $array[$i] === array() ) {
1216                                 unset( $array[$i] );
1217                         } else {
1218                                 break;
1219                         }
1220                 }
1221         }
1222
1223         /**
1224          * Returns JS code which calls mw.loader.register with the given
1225          * parameters. Has three calling conventions:
1226          *
1227          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1228          *        $dependencies, $group, $source, $skip
1229          *     ):
1230          *        Register a single module.
1231          *
1232          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1233          *        Register modules with the given names.
1234          *
1235          *   - ResourceLoader::makeLoaderRegisterScript( array(
1236          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1237          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1238          *        ...
1239          *     ) ):
1240          *        Registers modules with the given names and parameters.
1241          *
1242          * @param string $name Module name
1243          * @param int $version Module version number as a timestamp
1244          * @param array $dependencies List of module names on which this module depends
1245          * @param string $group Group which the module is in
1246          * @param string $source Source of the module, or 'local' if not foreign
1247          * @param string $skip Script body of the skip function
1248          * @return string
1249          */
1250         public static function makeLoaderRegisterScript( $name, $version = null,
1251                 $dependencies = null, $group = null, $source = null, $skip = null
1252         ) {
1253                 if ( is_array( $name ) ) {
1254                         // Build module name index
1255                         $index = array();
1256                         foreach ( $name as $i => &$module ) {
1257                                 $index[$module[0]] = $i;
1258                         }
1259
1260                         // Transform dependency names into indexes when possible, they will be resolved by
1261                         // mw.loader.register on the other end
1262                         foreach ( $name as &$module ) {
1263                                 if ( isset( $module[2] ) ) {
1264                                         foreach ( $module[2] as &$dependency ) {
1265                                                 if ( isset( $index[$dependency] ) ) {
1266                                                         $dependency = $index[$dependency];
1267                                                 }
1268                                         }
1269                                 }
1270                         }
1271
1272                         array_walk( $name, array( 'self', 'trimArray' ) );
1273
1274                         return Xml::encodeJsCall(
1275                                 'mw.loader.register',
1276                                 array( $name ),
1277                                 ResourceLoader::inDebugMode()
1278                         );
1279                 } else {
1280                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1281                         self::trimArray( $registration );
1282                         return Xml::encodeJsCall(
1283                                 'mw.loader.register',
1284                                 $registration,
1285                                 ResourceLoader::inDebugMode()
1286                         );
1287                 }
1288         }
1289
1290         /**
1291          * Returns JS code which calls mw.loader.addSource() with the given
1292          * parameters. Has two calling conventions:
1293          *
1294          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1295          *       Register a single source
1296          *
1297          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1298          *       Register sources with the given IDs and properties.
1299          *
1300          * @param string $id Source ID
1301          * @param array $properties Source properties (see addSource())
1302          * @return string
1303          */
1304         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1305                 if ( is_array( $id ) ) {
1306                         return Xml::encodeJsCall(
1307                                 'mw.loader.addSource',
1308                                 array( $id ),
1309                                 ResourceLoader::inDebugMode()
1310                         );
1311                 } else {
1312                         return Xml::encodeJsCall(
1313                                 'mw.loader.addSource',
1314                                 array( $id, $properties ),
1315                                 ResourceLoader::inDebugMode()
1316                         );
1317                 }
1318         }
1319
1320         /**
1321          * Returns JS code which runs given JS code if the client-side framework is
1322          * present.
1323          *
1324          * @param string $script JavaScript code
1325          * @return string
1326          */
1327         public static function makeLoaderConditionalScript( $script ) {
1328                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1329         }
1330
1331         /**
1332          * Returns JS code which will set the MediaWiki configuration array to
1333          * the given value.
1334          *
1335          * @param array $configuration List of configuration values keyed by variable name
1336          * @return string
1337          */
1338         public static function makeConfigSetScript( array $configuration ) {
1339                 return Xml::encodeJsCall(
1340                         'mw.config.set',
1341                         array( $configuration ),
1342                         ResourceLoader::inDebugMode()
1343                 );
1344         }
1345
1346         /**
1347          * Convert an array of module names to a packed query string.
1348          *
1349          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1350          * becomes 'foo.bar,baz|bar.baz,quux'
1351          * @param array $modules List of module names (strings)
1352          * @return string Packed query string
1353          */
1354         public static function makePackedModulesString( $modules ) {
1355                 $groups = array(); // array( prefix => array( suffixes ) )
1356                 foreach ( $modules as $module ) {
1357                         $pos = strrpos( $module, '.' );
1358                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1359                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1360                         $groups[$prefix][] = $suffix;
1361                 }
1362
1363                 $arr = array();
1364                 foreach ( $groups as $prefix => $suffixes ) {
1365                         $p = $prefix === '' ? '' : $prefix . '.';
1366                         $arr[] = $p . implode( ',', $suffixes );
1367                 }
1368                 $str = implode( '|', $arr );
1369                 return $str;
1370         }
1371
1372         /**
1373          * Determine whether debug mode was requested
1374          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1375          * @return bool
1376          */
1377         public static function inDebugMode() {
1378                 if ( self::$debugMode === null ) {
1379                         global $wgRequest, $wgResourceLoaderDebug;
1380                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1381                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1382                         );
1383                 }
1384                 return self::$debugMode;
1385         }
1386
1387         /**
1388          * Reset static members used for caching.
1389          *
1390          * Global state and $wgRequest are evil, but we're using it right
1391          * now and sometimes we need to be able to force ResourceLoader to
1392          * re-evaluate the context because it has changed (e.g. in the test suite).
1393          */
1394         public static function clearCache() {
1395                 self::$debugMode = null;
1396         }
1397
1398         /**
1399          * Build a load.php URL
1400          *
1401          * @since 1.24
1402          * @param string $source Name of the ResourceLoader source
1403          * @param ResourceLoaderContext $context
1404          * @param array $extraQuery
1405          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1406          */
1407         public function createLoaderURL( $source, ResourceLoaderContext $context,
1408                 $extraQuery = array()
1409         ) {
1410                 $query = self::createLoaderQuery( $context, $extraQuery );
1411                 $script = $this->getLoadScript( $source );
1412
1413                 // Prevent the IE6 extension check from being triggered (bug 28840)
1414                 // by appending a character that's invalid in Windows extensions ('*')
1415                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1416         }
1417
1418         /**
1419          * Build a load.php URL
1420          * @deprecated since 1.24, use createLoaderURL instead
1421          * @param array $modules Array of module names (strings)
1422          * @param string $lang Language code
1423          * @param string $skin Skin name
1424          * @param string|null $user User name. If null, the &user= parameter is omitted
1425          * @param string|null $version Versioning timestamp
1426          * @param bool $debug Whether the request should be in debug mode
1427          * @param string|null $only &only= parameter
1428          * @param bool $printable Printable mode
1429          * @param bool $handheld Handheld mode
1430          * @param array $extraQuery Extra query parameters to add
1431          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1432          */
1433         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1434                 $version = null, $debug = false, $only = null, $printable = false,
1435                 $handheld = false, $extraQuery = array()
1436         ) {
1437                 global $wgLoadScript;
1438
1439                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1440                         $only, $printable, $handheld, $extraQuery
1441                 );
1442
1443                 // Prevent the IE6 extension check from being triggered (bug 28840)
1444                 // by appending a character that's invalid in Windows extensions ('*')
1445                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1446         }
1447
1448         /**
1449          * Helper for createLoaderURL()
1450          *
1451          * @since 1.24
1452          * @see makeLoaderQuery
1453          * @param ResourceLoaderContext $context
1454          * @param array $extraQuery
1455          * @return array
1456          */
1457         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1458                 return self::makeLoaderQuery(
1459                         $context->getModules(),
1460                         $context->getLanguage(),
1461                         $context->getSkin(),
1462                         $context->getUser(),
1463                         $context->getVersion(),
1464                         $context->getDebug(),
1465                         $context->getOnly(),
1466                         $context->getRequest()->getBool( 'printable' ),
1467                         $context->getRequest()->getBool( 'handheld' ),
1468                         $extraQuery
1469                 );
1470         }
1471
1472         /**
1473          * Build a query array (array representation of query string) for load.php. Helper
1474          * function for makeLoaderURL().
1475          *
1476          * @param array $modules
1477          * @param string $lang
1478          * @param string $skin
1479          * @param string $user
1480          * @param string $version
1481          * @param bool $debug
1482          * @param string $only
1483          * @param bool $printable
1484          * @param bool $handheld
1485          * @param array $extraQuery
1486          *
1487          * @return array
1488          */
1489         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1490                 $version = null, $debug = false, $only = null, $printable = false,
1491                 $handheld = false, $extraQuery = array()
1492         ) {
1493                 $query = array(
1494                         'modules' => self::makePackedModulesString( $modules ),
1495                         'lang' => $lang,
1496                         'skin' => $skin,
1497                         'debug' => $debug ? 'true' : 'false',
1498                 );
1499                 if ( $user !== null ) {
1500                         $query['user'] = $user;
1501                 }
1502                 if ( $version !== null ) {
1503                         $query['version'] = $version;
1504                 }
1505                 if ( $only !== null ) {
1506                         $query['only'] = $only;
1507                 }
1508                 if ( $printable ) {
1509                         $query['printable'] = 1;
1510                 }
1511                 if ( $handheld ) {
1512                         $query['handheld'] = 1;
1513                 }
1514                 $query += $extraQuery;
1515
1516                 // Make queries uniform in order
1517                 ksort( $query );
1518                 return $query;
1519         }
1520
1521         /**
1522          * Check a module name for validity.
1523          *
1524          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1525          * at most 255 bytes.
1526          *
1527          * @param string $moduleName Module name to check
1528          * @return bool Whether $moduleName is a valid module name
1529          */
1530         public static function isValidModuleName( $moduleName ) {
1531                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1532         }
1533
1534         /**
1535          * Returns LESS compiler set up for use with MediaWiki
1536          *
1537          * @param Config $config
1538          * @throws MWException
1539          * @since 1.22
1540          * @return lessc
1541          */
1542         public static function getLessCompiler( Config $config ) {
1543                 // When called from the installer, it is possible that a required PHP extension
1544                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1545                 // exception (caught by the installer) to prevent a fatal error later on.
1546                 if ( !class_exists( 'lessc' ) ) {
1547                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1548                 }
1549                 if ( !function_exists( 'ctype_digit' ) ) {
1550                         throw new MWException( 'lessc requires the Ctype extension' );
1551                 }
1552
1553                 $less = new lessc();
1554                 $less->setPreserveComments( true );
1555                 $less->setVariables( self::getLessVars( $config ) );
1556                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1557                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1558                         $less->registerFunction( $name, $func );
1559                 }
1560                 return $less;
1561         }
1562
1563         /**
1564          * Get global LESS variables.
1565          *
1566          * @param Config $config
1567          * @since 1.22
1568          * @return array Map of variable names to string CSS values.
1569          */
1570         public static function getLessVars( Config $config ) {
1571                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1572                 // Sort by key to ensure consistent hashing for cache lookups.
1573                 ksort( $lessVars );
1574                 return $lessVars;
1575         }
1576 }