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