includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /** @var array Module name/ResourceLoaderModule object pairs */
  39         protected $modules = array();
  40
  41         /** @var array Associative array mapping module name to info associative array */
  42         protected $moduleInfos = array();
  43
  44         /** @var Config $config */
  45         private $config;
  46
  47         /**
  48          * @var array Associative array mapping framework ids to a list of names of test suite modules
  49          *      like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  50          */
  51         protected $testModuleNames = array();
  52
  53         /** @var array E.g. array( 'source-id' => 'http://.../load.php' ) */
  54         protected $sources = array();
  55
  56         /** @var bool */
  57         protected $hasErrors = false;
  58
  59         /**
  60          * Load information stored in the database about modules.
  61          *
  62          * This method grabs modules dependencies from the database and updates modules
  63          * objects.
  64          *
  65          * This is not inside the module code because it is much faster to
  66          * request all of the information at once than it is to have each module
  67          * requests its own information. This sacrifice of modularity yields a substantial
  68          * performance improvement.
  69          *
  70          * @param array $modules List of module names to preload information for
  71          * @param ResourceLoaderContext $context Context to load the information within
  72          */
  73         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  74                 if ( !count( $modules ) ) {
  75                         // Or else Database*::select() will explode, plus it's cheaper!
  76                         return;
  77                 }
  78                 $dbr = wfGetDB( DB_SLAVE );
  79                 $skin = $context->getSkin();
  80                 $lang = $context->getLanguage();
  81
  82                 // Get file dependency information
  83                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  84                                 'md_module' => $modules,
  85                                 'md_skin' => $skin
  86                         ), __METHOD__
  87                 );
  88
  89                 // Set modules' dependencies
  90                 $modulesWithDeps = array();
  91                 foreach ( $res as $row ) {
  92                         $module = $this->getModule( $row->md_module );
  93                         if ( $module ) {
  94                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
  95                                 $modulesWithDeps[] = $row->md_module;
  96                         }
  97                 }
  98
  99                 // Register the absence of a dependency row too
 100                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 101                         $module = $this->getModule( $name );
 102                         if ( $module ) {
 103                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 104                         }
 105                 }
 106
 107                 // Get message blob mtimes. Only do this for modules with messages
 108                 $modulesWithMessages = array();
 109                 foreach ( $modules as $name ) {
 110                         $module = $this->getModule( $name );
 111                         if ( $module && count( $module->getMessages() ) ) {
 112                                 $modulesWithMessages[] = $name;
 113                         }
 114                 }
 115                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 116                 if ( count( $modulesWithMessages ) ) {
 117                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 118                                         'mr_resource' => $modulesWithMessages,
 119                                         'mr_lang' => $lang
 120                                 ), __METHOD__
 121                         );
 122                         foreach ( $res as $row ) {
 123                                 $module = $this->getModule( $row->mr_resource );
 124                                 if ( $module ) {
 125                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 126                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 127                                 }
 128                         }
 129                 }
 130                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 131                         $module = $this->getModule( $name );
 132                         if ( $module ) {
 133                                 $module->setMsgBlobMtime( $lang, 0 );
 134                         }
 135                 }
 136         }
 137
 138         /**
 139          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 140          *
 141          * Available filters are:
 142          *
 143          *    - minify-js \see JavaScriptMinifier::minify
 144          *    - minify-css \see CSSMin::minify
 145          *
 146          * If $data is empty, only contains whitespace or the filter was unknown,
 147          * $data is returned unmodified.
 148          *
 149          * @param string $filter Name of filter to run
 150          * @param string $data Text to filter, such as JavaScript or CSS text
 151          * @param string $cacheReport Whether to include the cache key report
 152          * @return string Filtered data, or a comment containing an error message
 153          */
 154         public function filter( $filter, $data, $cacheReport = true ) {
 155                 wfProfileIn( __METHOD__ );
 156
 157                 // For empty/whitespace-only data or for unknown filters, don't perform
 158                 // any caching or processing
 159                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 160                         wfProfileOut( __METHOD__ );
 161                         return $data;
 162                 }
 163
 164                 // Try for cache hit
 165                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 166                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 167                 $cache = wfGetCache( CACHE_ANYTHING );
 168                 $cacheEntry = $cache->get( $key );
 169                 if ( is_string( $cacheEntry ) ) {
 170                         wfIncrStats( "rl-$filter-cache-hits" );
 171                         wfProfileOut( __METHOD__ );
 172                         return $cacheEntry;
 173                 }
 174
 175                 $result = '';
 176                 // Run the filter - we've already verified one of these will work
 177                 try {
 178                         wfIncrStats( "rl-$filter-cache-misses" );
 179                         switch ( $filter ) {
 180                                 case 'minify-js':
 181                                         $result = JavaScriptMinifier::minify( $data,
 182                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 183                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 184                                         );
 185                                         if ( $cacheReport ) {
 186                                                 $result .= "\n/* cache key: $key */";
 187                                         }
 188                                         break;
 189                                 case 'minify-css':
 190                                         $result = CSSMin::minify( $data );
 191                                         if ( $cacheReport ) {
 192                                                 $result .= "\n/* cache key: $key */";
 193                                         }
 194                                         break;
 195                         }
 196
 197                         // Save filtered text to Memcached
 198                         $cache->set( $key, $result );
 199                 } catch ( Exception $e ) {
 200                         MWExceptionHandler::logException( $e );
 201                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 202                         $this->hasErrors = true;
 203                         // Return exception as a comment
 204                         $result = self::formatException( $e );
 205                 }
 206
 207                 wfProfileOut( __METHOD__ );
 208
 209                 return $result;
 210         }
 211
 212         /* Methods */
 213
 214         /**
 215          * Register core modules and runs registration hooks.
 216          * @param Config|null $config
 217          */
 218         public function __construct( Config $config = null ) {
 219                 global $IP;
 220
 221                 wfProfileIn( __METHOD__ );
 222
 223                 if ( $config === null ) {
 224                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 225                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 226                 }
 227
 228                 $this->config = $config;
 229
 230                 // Add 'local' source first
 231                 $this->addSource( 'local', wfScript( 'load' ) );
 232
 233                 // Add other sources
 234                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 235
 236                 // Register core modules
 237                 $this->register( include "$IP/resources/Resources.php" );
 238                 // Register extension modules
 239                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 240                 $this->register( $config->get( 'ResourceModules' ) );
 241
 242                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 243                         $this->registerTestModules();
 244                 }
 245
 246                 wfProfileOut( __METHOD__ );
 247         }
 248
 249         /**
 250          * @return Config
 251          */
 252         public function getConfig() {
 253                 return $this->config;
 254         }
 255
 256         /**
 257          * Register a module with the ResourceLoader system.
 258          *
 259          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 260          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 261          *   this may also be a ResourceLoaderModule object. Optional when using
 262          *   multiple-registration calling style.
 263          * @throws MWException If a duplicate module registration is attempted
 264          * @throws MWException If a module name contains illegal characters (pipes or commas)
 265          * @throws MWException If something other than a ResourceLoaderModule is being registered
 266          * @return bool False if there were any errors, in which case one or more modules were
 267          *   not registered
 268          */
 269         public function register( $name, $info = null ) {
 270                 wfProfileIn( __METHOD__ );
 271
 272                 // Allow multiple modules to be registered in one call
 273                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 274                 foreach ( $registrations as $name => $info ) {
 275                         // Disallow duplicate registrations
 276                         if ( isset( $this->moduleInfos[$name] ) ) {
 277                                 wfProfileOut( __METHOD__ );
 278                                 // A module has already been registered by this name
 279                                 throw new MWException(
 280                                         'ResourceLoader duplicate registration error. ' .
 281                                         'Another module has already been registered as ' . $name
 282                                 );
 283                         }
 284
 285                         // Check $name for validity
 286                         if ( !self::isValidModuleName( $name ) ) {
 287                                 wfProfileOut( __METHOD__ );
 288                                 throw new MWException( "ResourceLoader module name '$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                                 wfProfileOut( __METHOD__ );
 302                                 throw new MWException(
 303                                         'ResourceLoader module info type error for module \'' . $name .
 304                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 305                                 );
 306                         }
 307
 308                         // Last-minute changes
 309
 310                         // Apply custom skin-defined styles to existing modules.
 311                         if ( $this->isFileModule( $name ) ) {
 312                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 313                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 314                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 315                                                 continue;
 316                                         }
 317
 318                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 319                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 320                                         if ( isset( $skinStyles[$name] ) ) {
 321                                                 $paths = (array)$skinStyles[$name];
 322                                                 $styleFiles = array();
 323                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 324                                                 $paths = (array)$skinStyles['+' . $name];
 325                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 326                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 327                                                         array();
 328                                         } else {
 329                                                 continue;
 330                                         }
 331
 332                                         // Add new file paths, remapping them to refer to our directories and not use settings
 333                                         // from the module we're modifying. These can come from the base definition or be defined
 334                                         // for each module.
 335                                         list( $localBasePath, $remoteBasePath ) =
 336                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 337                                         list( $localBasePath, $remoteBasePath ) =
 338                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 339
 340                                         foreach ( $paths as $path ) {
 341                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 342                                         }
 343
 344                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 345                                 }
 346                         }
 347                 }
 348
 349                 wfProfileOut( __METHOD__ );
 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                 wfProfileIn( __METHOD__ );
 364
 365                 // Get core test suites
 366                 $testModules = array();
 367                 $testModules['qunit'] = array();
 368                 // Get other test suites (e.g. from extensions)
 369                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 370
 371                 // Add the testrunner (which configures QUnit) to the dependencies.
 372                 // Since it must be ready before any of the test suites are executed.
 373                 foreach ( $testModules['qunit'] as &$module ) {
 374                         // Make sure all test modules are top-loading so that when QUnit starts
 375                         // on document-ready, it will run once and finish. If some tests arrive
 376                         // later (possibly after QUnit has already finished) they will be ignored.
 377                         $module['position'] = 'top';
 378                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 379                 }
 380
 381                 $testModules['qunit'] =
 382                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 383
 384                 foreach ( $testModules as $id => $names ) {
 385                         // Register test modules
 386                         $this->register( $testModules[$id] );
 387
 388                         // Keep track of their names so that they can be loaded together
 389                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 390                 }
 391
 392                 wfProfileOut( __METHOD__ );
 393         }
 394
 395         /**
 396          * Add a foreign source of modules.
 397          *
 398          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 399          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 400          *  backwards-compatibility.
 401          * @throws MWException
 402          */
 403         public function addSource( $id, $loadUrl = null ) {
 404                 // Allow multiple sources to be registered in one call
 405                 if ( is_array( $id ) ) {
 406                         foreach ( $id as $key => $value ) {
 407                                 $this->addSource( $key, $value );
 408                         }
 409                         return;
 410                 }
 411
 412                 // Disallow duplicates
 413                 if ( isset( $this->sources[$id] ) ) {
 414                         throw new MWException(
 415                                 'ResourceLoader duplicate source addition error. ' .
 416                                 'Another source has already been registered as ' . $id
 417                         );
 418                 }
 419
 420                 // Pre 1.24 backwards-compatibility
 421                 if ( is_array( $loadUrl ) ) {
 422                         if ( !isset( $loadUrl['loadScript'] ) ) {
 423                                 throw new MWException(
 424                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 425                                 );
 426                         }
 427
 428                         $loadUrl = $loadUrl['loadScript'];
 429                 }
 430
 431                 $this->sources[$id] = $loadUrl;
 432         }
 433
 434         /**
 435          * Get a list of module names.
 436          *
 437          * @return array List of module names
 438          */
 439         public function getModuleNames() {
 440                 return array_keys( $this->moduleInfos );
 441         }
 442
 443         /**
 444          * Get a list of test module names for one (or all) frameworks.
 445          *
 446          * If the given framework id is unknkown, or if the in-object variable is not an array,
 447          * then it will return an empty array.
 448          *
 449          * @param string $framework Get only the test module names for one
 450          *   particular framework (optional)
 451          * @return array
 452          */
 453         public function getTestModuleNames( $framework = 'all' ) {
 454                 /** @todo api siteinfo prop testmodulenames modulenames */
 455                 if ( $framework == 'all' ) {
 456                         return $this->testModuleNames;
 457                 } elseif ( isset( $this->testModuleNames[$framework] )
 458                         && is_array( $this->testModuleNames[$framework] )
 459                 ) {
 460                         return $this->testModuleNames[$framework];
 461                 } else {
 462                         return array();
 463                 }
 464         }
 465
 466         /**
 467          * Get the ResourceLoaderModule object for a given module name.
 468          *
 469          * If an array of module parameters exists but a ResourceLoaderModule object has not
 470          * yet been instantiated, this method will instantiate and cache that object such that
 471          * subsequent calls simply return the same object.
 472          *
 473          * @param string $name Module name
 474          * @return ResourceLoaderModule|null If module has been registered, return a
 475          *  ResourceLoaderModule instance. Otherwise, return null.
 476          */
 477         public function getModule( $name ) {
 478                 if ( !isset( $this->modules[$name] ) ) {
 479                         if ( !isset( $this->moduleInfos[$name] ) ) {
 480                                 // No such module
 481                                 return null;
 482                         }
 483                         // Construct the requested object
 484                         $info = $this->moduleInfos[$name];
 485                         /** @var ResourceLoaderModule $object */
 486                         if ( isset( $info['object'] ) ) {
 487                                 // Object given in info array
 488                                 $object = $info['object'];
 489                         } else {
 490                                 if ( !isset( $info['class'] ) ) {
 491                                         $class = 'ResourceLoaderFileModule';
 492                                 } else {
 493                                         $class = $info['class'];
 494                                 }
 495                                 /** @var ResourceLoaderModule $object */
 496                                 $object = new $class( $info );
 497                                 $object->setConfig( $this->getConfig() );
 498                         }
 499                         $object->setName( $name );
 500                         $this->modules[$name] = $object;
 501                 }
 502
 503                 return $this->modules[$name];
 504         }
 505
 506         /**
 507          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 508          *
 509          * @param string $name Module name
 510          * @return bool
 511          */
 512         protected function isFileModule( $name ) {
 513                 if ( !isset( $this->moduleInfos[$name] ) ) {
 514                         return false;
 515                 }
 516                 $info = $this->moduleInfos[$name];
 517                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 518                         return false;
 519                 }
 520                 return true;
 521         }
 522
 523         /**
 524          * Get the list of sources.
 525          *
 526          * @return array Like array( id => load.php url, .. )
 527          */
 528         public function getSources() {
 529                 return $this->sources;
 530         }
 531
 532         /**
 533          * Get the URL to the load.php endpoint for the given
 534          * ResourceLoader source
 535          *
 536          * @since 1.24
 537          * @param string $source
 538          * @throws MWException On an invalid $source name
 539          * @return string
 540          */
 541         public function getLoadScript( $source ) {
 542                 if ( !isset( $this->sources[$source] ) ) {
 543                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 544                 }
 545                 return $this->sources[$source];
 546         }
 547
 548         /**
 549          * Output a response to a load request, including the content-type header.
 550          *
 551          * @param ResourceLoaderContext $context Context in which a response should be formed
 552          */
 553         public function respond( ResourceLoaderContext $context ) {
 554                 // Use file cache if enabled and available...
 555                 if ( $this->config->get( 'UseFileCache' ) ) {
 556                         $fileCache = ResourceFileCache::newFromContext( $context );
 557                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 558                                 return; // output handled
 559                         }
 560                 }
 561
 562                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 563                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 564                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 565                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 566                 // the whole thing in our own output buffer to be sure the active buffer
 567                 // doesn't use ob_gzhandler.
 568                 // See http://bugs.php.net/bug.php?id=36514
 569                 ob_start();
 570
 571                 wfProfileIn( __METHOD__ );
 572                 $errors = '';
 573
 574                 // Find out which modules are missing and instantiate the others
 575                 $modules = array();
 576                 $missing = array();
 577                 foreach ( $context->getModules() as $name ) {
 578                         $module = $this->getModule( $name );
 579                         if ( $module ) {
 580                                 // Do not allow private modules to be loaded from the web.
 581                                 // This is a security issue, see bug 34907.
 582                                 if ( $module->getGroup() === 'private' ) {
 583                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 584                                         $this->hasErrors = true;
 585                                         // Add exception to the output as a comment
 586                                         $errors .= self::makeComment( "Cannot show private module \"$name\"" );
 587
 588                                         continue;
 589                                 }
 590                                 $modules[$name] = $module;
 591                         } else {
 592                                 $missing[] = $name;
 593                         }
 594                 }
 595
 596                 // Preload information needed to the mtime calculation below
 597                 try {
 598                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 599                 } catch ( Exception $e ) {
 600                         MWExceptionHandler::logException( $e );
 601                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 602                         $this->hasErrors = true;
 603                         // Add exception to the output as a comment
 604                         $errors .= self::formatException( $e );
 605                 }
 606
 607                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 608
 609                 // To send Last-Modified and support If-Modified-Since, we need to detect
 610                 // the last modified time
 611                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 612                 foreach ( $modules as $module ) {
 613                         /**
 614                          * @var $module ResourceLoaderModule
 615                          */
 616                         try {
 617                                 // Calculate maximum modified time
 618                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 619                         } catch ( Exception $e ) {
 620                                 MWExceptionHandler::logException( $e );
 621                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 622                                 $this->hasErrors = true;
 623                                 // Add exception to the output as a comment
 624                                 $errors .= self::formatException( $e );
 625                         }
 626                 }
 627
 628                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 629
 630                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 631                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 632                         wfProfileOut( __METHOD__ );
 633                         return; // output handled (buffers cleared)
 634                 }
 635
 636                 // Generate a response
 637                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 638
 639                 // Prepend comments indicating exceptions
 640                 $response = $errors . $response;
 641
 642                 // Capture any PHP warnings from the output buffer and append them to the
 643                 // response in a comment if we're in debug mode.
 644                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 645                         $response = self::makeComment( $warnings ) . $response;
 646                         $this->hasErrors = true;
 647                 }
 648
 649                 // Save response to file cache unless there are errors
 650                 if ( isset( $fileCache ) && !$errors && !count( $missing ) ) {
 651                         // Cache single modules...and other requests if there are enough hits
 652                         if ( ResourceFileCache::useFileCache( $context ) ) {
 653                                 if ( $fileCache->isCacheWorthy() ) {
 654                                         $fileCache->saveText( $response );
 655                                 } else {
 656                                         $fileCache->incrMissesRecent( $context->getRequest() );
 657                                 }
 658                         }
 659                 }
 660
 661                 // Send content type and cache related headers
 662                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 663
 664                 // Remove the output buffer and output the response
 665                 ob_end_clean();
 666                 echo $response;
 667
 668                 wfProfileOut( __METHOD__ );
 669         }
 670
 671         /**
 672          * Send content type and last modified headers to the client.
 673          * @param ResourceLoaderContext $context
 674          * @param string $mtime TS_MW timestamp to use for last-modified
 675          * @param bool $errors Whether there are commented-out errors in the response
 676          * @return void
 677          */
 678         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 679                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 680                 // If a version wasn't specified we need a shorter expiry time for updates
 681                 // to propagate to clients quickly
 682                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 683                 if ( is_null( $context->getVersion() ) || $errors ) {
 684                         $maxage = $rlMaxage['unversioned']['client'];
 685                         $smaxage = $rlMaxage['unversioned']['server'];
 686                 // If a version was specified we can use a longer expiry time since changing
 687                 // version numbers causes cache misses
 688                 } else {
 689                         $maxage = $rlMaxage['versioned']['client'];
 690                         $smaxage = $rlMaxage['versioned']['server'];
 691                 }
 692                 if ( $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 that can be returned to the user
 817          */
 818         public static function formatException( $e ) {
 819                 global $wgShowExceptionDetails;
 820
 821                 if ( $wgShowExceptionDetails ) {
 822                         return self::makeComment( $e->__toString() );
 823                 } else {
 824                         return self::makeComment( wfMessage( 'internalerror' )->text() );
 825                 }
 826         }
 827
 828         /**
 829          * Generate code for a response.
 830          *
 831          * @param ResourceLoaderContext $context Context in which to generate a response
 832          * @param array $modules List of module objects keyed by module name
 833          * @param array $missing List of requested module names that are unregistered (optional)
 834          * @return string Response data
 835          */
 836         public function makeModuleResponse( ResourceLoaderContext $context,
 837                 array $modules, array $missing = array()
 838         ) {
 839                 $out = '';
 840                 $exceptions = '';
 841                 $states = array();
 842
 843                 if ( !count( $modules ) && !count( $missing ) ) {
 844                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 845    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 846    no modules were requested. Max made me put this here. */";
 847                 }
 848
 849                 wfProfileIn( __METHOD__ );
 850
 851                 // Pre-fetch blobs
 852                 if ( $context->shouldIncludeMessages() ) {
 853                         try {
 854                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 855                         } catch ( Exception $e ) {
 856                                 MWExceptionHandler::logException( $e );
 857                                 wfDebugLog(
 858                                         'resourceloader',
 859                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 860                                 );
 861                                 $this->hasErrors = true;
 862                                 // Add exception to the output as a comment
 863                                 $exceptions .= self::formatException( $e );
 864                         }
 865                 } else {
 866                         $blobs = array();
 867                 }
 868
 869                 foreach ( $missing as $name ) {
 870                         $states[$name] = 'missing';
 871                 }
 872
 873                 // Generate output
 874                 $isRaw = false;
 875                 foreach ( $modules as $name => $module ) {
 876                         /**
 877                          * @var $module ResourceLoaderModule
 878                          */
 879
 880                         wfProfileIn( __METHOD__ . '-' . $name );
 881                         try {
 882                                 $scripts = '';
 883                                 if ( $context->shouldIncludeScripts() ) {
 884                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 885                                         // However, we can't do this if the module doesn't support it
 886                                         // We also can't do this if there is an only= parameter, because we have to give
 887                                         // the module a way to return a load.php URL without causing an infinite loop
 888                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 889                                                 $scripts = $module->getScriptURLsForDebug( $context );
 890                                         } else {
 891                                                 $scripts = $module->getScript( $context );
 892                                                 // rtrim() because there are usually a few line breaks
 893                                                 // after the last ';'. A new line at EOF, a new line
 894                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 895                                                 if ( is_string( $scripts )
 896                                                         && strlen( $scripts )
 897                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 898                                                 ) {
 899                                                         // Append semicolon to prevent weird bugs caused by files not
 900                                                         // terminating their statements right (bug 27054)
 901                                                         $scripts .= ";\n";
 902                                                 }
 903                                         }
 904                                 }
 905                                 // Styles
 906                                 $styles = array();
 907                                 if ( $context->shouldIncludeStyles() ) {
 908                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 909                                         // that don't *have* any stylesheets (bug 38024).
 910                                         $stylePairs = $module->getStyles( $context );
 911                                         if ( count( $stylePairs ) ) {
 912                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 913                                                 // See comment near shouldIncludeScripts() for more details
 914                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 915                                                         $styles = array(
 916                                                                 'url' => $module->getStyleURLsForDebug( $context )
 917                                                         );
 918                                                 } else {
 919                                                         // Minify CSS before embedding in mw.loader.implement call
 920                                                         // (unless in debug mode)
 921                                                         if ( !$context->getDebug() ) {
 922                                                                 foreach ( $stylePairs as $media => $style ) {
 923                                                                         // Can be either a string or an array of strings.
 924                                                                         if ( is_array( $style ) ) {
 925                                                                                 $stylePairs[$media] = array();
 926                                                                                 foreach ( $style as $cssText ) {
 927                                                                                         if ( is_string( $cssText ) ) {
 928                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 929                                                                                         }
 930                                                                                 }
 931                                                                         } elseif ( is_string( $style ) ) {
 932                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 933                                                                         }
 934                                                                 }
 935                                                         }
 936                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 937                                                         $styles = array(
 938                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 939                                                         );
 940                                                 }
 941                                         }
 942                                 }
 943
 944                                 // Messages
 945                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 946
 947                                 // Append output
 948                                 switch ( $context->getOnly() ) {
 949                                         case 'scripts':
 950                                                 if ( is_string( $scripts ) ) {
 951                                                         // Load scripts raw...
 952                                                         $out .= $scripts;
 953                                                 } elseif ( is_array( $scripts ) ) {
 954                                                         // ...except when $scripts is an array of URLs
 955                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 956                                                 }
 957                                                 break;
 958                                         case 'styles':
 959                                                 // We no longer seperate into media, they are all combined now with
 960                                                 // custom media type groups into @media .. {} sections as part of the css string.
 961                                                 // Module returns either an empty array or a numerical array with css strings.
 962                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 963                                                 break;
 964                                         case 'messages':
 965                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 966                                                 break;
 967                                         default:
 968                                                 $out .= self::makeLoaderImplementScript(
 969                                                         $name,
 970                                                         $scripts,
 971                                                         $styles,
 972                                                         new XmlJsCode( $messagesBlob )
 973                                                 );
 974                                                 break;
 975                                 }
 976                         } catch ( Exception $e ) {
 977                                 MWExceptionHandler::logException( $e );
 978                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
 979                                 $this->hasErrors = true;
 980                                 // Add exception to the output as a comment
 981                                 $exceptions .= self::formatException( $e );
 982
 983                                 // Respond to client with error-state instead of module implementation
 984                                 $states[$name] = 'error';
 985                                 unset( $modules[$name] );
 986                         }
 987                         $isRaw |= $module->isRaw();
 988                         wfProfileOut( __METHOD__ . '-' . $name );
 989                 }
 990
 991                 // Update module states
 992                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
 993                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
 994                                 // Set the state of modules loaded as only scripts to ready as
 995                                 // they don't have an mw.loader.implement wrapper that sets the state
 996                                 foreach ( $modules as $name => $module ) {
 997                                         $states[$name] = 'ready';
 998                                 }
 999                         }
1000
1001                         // Set the state of modules we didn't respond to with mw.loader.implement
1002                         if ( count( $states ) ) {
1003                                 $out .= self::makeLoaderStateScript( $states );
1004                         }
1005                 } else {
1006                         if ( count( $states ) ) {
1007                                 $exceptions .= self::makeComment(
1008                                         'Problematic modules: ' . FormatJson::encode( $states, ResourceLoader::inDebugMode() )
1009                                 );
1010                         }
1011                 }
1012
1013                 if ( !$context->getDebug() ) {
1014                         if ( $context->getOnly() === 'styles' ) {
1015                                 $out = $this->filter( 'minify-css', $out );
1016                         } else {
1017                                 $out = $this->filter( 'minify-js', $out );
1018                         }
1019                 }
1020
1021                 wfProfileOut( __METHOD__ );
1022                 return $exceptions . $out;
1023         }
1024
1025         /* Static Methods */
1026
1027         /**
1028          * Return JS code that calls mw.loader.implement with given module properties.
1029          *
1030          * @param string $name Module name
1031          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1032          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1033          *   to CSS files keyed by media type
1034          * @param mixed $messages List of messages associated with this module. May either be an
1035          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1036          *   the same data, wrapped in an XmlJsCode object.
1037          * @throws MWException
1038          * @return string
1039          */
1040         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
1041                 if ( is_string( $scripts ) ) {
1042                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1043                 } elseif ( !is_array( $scripts ) ) {
1044                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1045                 }
1046                 return Xml::encodeJsCall(
1047                         'mw.loader.implement',
1048                         array(
1049                                 $name,
1050                                 $scripts,
1051                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1052                                 // Although these variables are associative arrays, which become javascript
1053                                 // objects through json_encode. In many cases they will be empty arrays, and
1054                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1055                                 // output javascript "[]" instead of "{}". This fixes that.
1056                                 (object)$styles,
1057                                 (object)$messages
1058                         ),
1059                         ResourceLoader::inDebugMode()
1060                 );
1061         }
1062
1063         /**
1064          * Returns JS code which, when called, will register a given list of messages.
1065          *
1066          * @param mixed $messages Either an associative array mapping message key to value, or a
1067          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1068          * @return string
1069          */
1070         public static function makeMessageSetScript( $messages ) {
1071                 return Xml::encodeJsCall(
1072                         'mw.messages.set',
1073                         array( (object)$messages ),
1074                         ResourceLoader::inDebugMode()
1075                 );
1076         }
1077
1078         /**
1079          * Combines an associative array mapping media type to CSS into a
1080          * single stylesheet with "@media" blocks.
1081          *
1082          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1083          * @return array
1084          */
1085         public static function makeCombinedStyles( array $stylePairs ) {
1086                 $out = array();
1087                 foreach ( $stylePairs as $media => $styles ) {
1088                         // ResourceLoaderFileModule::getStyle can return the styles
1089                         // as a string or an array of strings. This is to allow separation in
1090                         // the front-end.
1091                         $styles = (array)$styles;
1092                         foreach ( $styles as $style ) {
1093                                 $style = trim( $style );
1094                                 // Don't output an empty "@media print { }" block (bug 40498)
1095                                 if ( $style !== '' ) {
1096                                         // Transform the media type based on request params and config
1097                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1098                                         $media = OutputPage::transformCssMedia( $media );
1099
1100                                         if ( $media === '' || $media == 'all' ) {
1101                                                 $out[] = $style;
1102                                         } elseif ( is_string( $media ) ) {
1103                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1104                                         }
1105                                         // else: skip
1106                                 }
1107                         }
1108                 }
1109                 return $out;
1110         }
1111
1112         /**
1113          * Returns a JS call to mw.loader.state, which sets the state of a
1114          * module or modules to a given value. Has two calling conventions:
1115          *
1116          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1117          *         Set the state of a single module called $name to $state
1118          *
1119          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1120          *         Set the state of modules with the given names to the given states
1121          *
1122          * @param string $name
1123          * @param string $state
1124          * @return string
1125          */
1126         public static function makeLoaderStateScript( $name, $state = null ) {
1127                 if ( is_array( $name ) ) {
1128                         return Xml::encodeJsCall(
1129                                 'mw.loader.state',
1130                                 array( $name ),
1131                                 ResourceLoader::inDebugMode()
1132                         );
1133                 } else {
1134                         return Xml::encodeJsCall(
1135                                 'mw.loader.state',
1136                                 array( $name, $state ),
1137                                 ResourceLoader::inDebugMode()
1138                         );
1139                 }
1140         }
1141
1142         /**
1143          * Returns JS code which calls the script given by $script. The script will
1144          * be called with local variables name, version, dependencies and group,
1145          * which will have values corresponding to $name, $version, $dependencies
1146          * and $group as supplied.
1147          *
1148          * @param string $name Module name
1149          * @param int $version Module version number as a timestamp
1150          * @param array $dependencies List of module names on which this module depends
1151          * @param string $group Group which the module is in.
1152          * @param string $source Source of the module, or 'local' if not foreign.
1153          * @param string $script JavaScript code
1154          * @return string
1155          */
1156         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1157                 $group, $source, $script
1158         ) {
1159                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1160                 return Xml::encodeJsCall(
1161                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1162                         array( $name, $version, $dependencies, $group, $source ),
1163                         ResourceLoader::inDebugMode()
1164                 );
1165         }
1166
1167         /**
1168          * Returns JS code which calls mw.loader.register with the given
1169          * parameters. Has three calling conventions:
1170          *
1171          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1172          *        $dependencies, $group, $source, $skip
1173          *     ):
1174          *        Register a single module.
1175          *
1176          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1177          *        Register modules with the given names.
1178          *
1179          *   - ResourceLoader::makeLoaderRegisterScript( array(
1180          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1181          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1182          *        ...
1183          *     ) ):
1184          *        Registers modules with the given names and parameters.
1185          *
1186          * @param string $name Module name
1187          * @param int $version Module version number as a timestamp
1188          * @param array $dependencies List of module names on which this module depends
1189          * @param string $group Group which the module is in
1190          * @param string $source Source of the module, or 'local' if not foreign
1191          * @param string $skip Script body of the skip function
1192          * @return string
1193          */
1194         public static function makeLoaderRegisterScript( $name, $version = null,
1195                 $dependencies = null, $group = null, $source = null, $skip = null
1196         ) {
1197                 if ( is_array( $name ) ) {
1198                         return Xml::encodeJsCall(
1199                                 'mw.loader.register',
1200                                 array( $name ),
1201                                 ResourceLoader::inDebugMode()
1202                         );
1203                 } else {
1204                         $version = (int)$version > 1 ? (int)$version : 1;
1205                         return Xml::encodeJsCall(
1206                                 'mw.loader.register',
1207                                 array( $name, $version, $dependencies, $group, $source, $skip ),
1208                                 ResourceLoader::inDebugMode()
1209                         );
1210                 }
1211         }
1212
1213         /**
1214          * Returns JS code which calls mw.loader.addSource() with the given
1215          * parameters. Has two calling conventions:
1216          *
1217          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1218          *       Register a single source
1219          *
1220          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1221          *       Register sources with the given IDs and properties.
1222          *
1223          * @param string $id Source ID
1224          * @param array $properties Source properties (see addSource())
1225          * @return string
1226          */
1227         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1228                 if ( is_array( $id ) ) {
1229                         return Xml::encodeJsCall(
1230                                 'mw.loader.addSource',
1231                                 array( $id ),
1232                                 ResourceLoader::inDebugMode()
1233                         );
1234                 } else {
1235                         return Xml::encodeJsCall(
1236                                 'mw.loader.addSource',
1237                                 array( $id, $properties ),
1238                                 ResourceLoader::inDebugMode()
1239                         );
1240                 }
1241         }
1242
1243         /**
1244          * Returns JS code which runs given JS code if the client-side framework is
1245          * present.
1246          *
1247          * @param string $script JavaScript code
1248          * @return string
1249          */
1250         public static function makeLoaderConditionalScript( $script ) {
1251                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1252         }
1253
1254         /**
1255          * Returns JS code which will set the MediaWiki configuration array to
1256          * the given value.
1257          *
1258          * @param array $configuration List of configuration values keyed by variable name
1259          * @return string
1260          */
1261         public static function makeConfigSetScript( array $configuration ) {
1262                 return Xml::encodeJsCall(
1263                         'mw.config.set',
1264                         array( $configuration ),
1265                         ResourceLoader::inDebugMode()
1266                 );
1267         }
1268
1269         /**
1270          * Convert an array of module names to a packed query string.
1271          *
1272          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1273          * becomes 'foo.bar,baz|bar.baz,quux'
1274          * @param array $modules List of module names (strings)
1275          * @return string Packed query string
1276          */
1277         public static function makePackedModulesString( $modules ) {
1278                 $groups = array(); // array( prefix => array( suffixes ) )
1279                 foreach ( $modules as $module ) {
1280                         $pos = strrpos( $module, '.' );
1281                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1282                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1283                         $groups[$prefix][] = $suffix;
1284                 }
1285
1286                 $arr = array();
1287                 foreach ( $groups as $prefix => $suffixes ) {
1288                         $p = $prefix === '' ? '' : $prefix . '.';
1289                         $arr[] = $p . implode( ',', $suffixes );
1290                 }
1291                 $str = implode( '|', $arr );
1292                 return $str;
1293         }
1294
1295         /**
1296          * Determine whether debug mode was requested
1297          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1298          * @return bool
1299          */
1300         public static function inDebugMode() {
1301                 if ( self::$debugMode === null ) {
1302                         global $wgRequest, $wgResourceLoaderDebug;
1303                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1304                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1305                         );
1306                 }
1307                 return self::$debugMode;
1308         }
1309
1310         /**
1311          * Reset static members used for caching.
1312          *
1313          * Global state and $wgRequest are evil, but we're using it right
1314          * now and sometimes we need to be able to force ResourceLoader to
1315          * re-evaluate the context because it has changed (e.g. in the test suite).
1316          */
1317         public static function clearCache() {
1318                 self::$debugMode = null;
1319         }
1320
1321         /**
1322          * Build a load.php URL
1323          *
1324          * @since 1.24
1325          * @param string $source Name of the ResourceLoader source
1326          * @param ResourceLoaderContext $context
1327          * @param array $extraQuery
1328          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1329          */
1330         public function createLoaderURL( $source, ResourceLoaderContext $context,
1331                 $extraQuery = array()
1332         ) {
1333                 $query = self::createLoaderQuery( $context, $extraQuery );
1334                 $script = $this->getLoadScript( $source );
1335
1336                 // Prevent the IE6 extension check from being triggered (bug 28840)
1337                 // by appending a character that's invalid in Windows extensions ('*')
1338                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1339         }
1340
1341         /**
1342          * Build a load.php URL
1343          * @deprecated since 1.24, use createLoaderURL instead
1344          * @param array $modules Array of module names (strings)
1345          * @param string $lang Language code
1346          * @param string $skin Skin name
1347          * @param string|null $user User name. If null, the &user= parameter is omitted
1348          * @param string|null $version Versioning timestamp
1349          * @param bool $debug Whether the request should be in debug mode
1350          * @param string|null $only &only= parameter
1351          * @param bool $printable Printable mode
1352          * @param bool $handheld Handheld mode
1353          * @param array $extraQuery Extra query parameters to add
1354          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1355          */
1356         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1357                 $version = null, $debug = false, $only = null, $printable = false,
1358                 $handheld = false, $extraQuery = array()
1359         ) {
1360                 global $wgLoadScript;
1361
1362                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1363                         $only, $printable, $handheld, $extraQuery
1364                 );
1365
1366                 // Prevent the IE6 extension check from being triggered (bug 28840)
1367                 // by appending a character that's invalid in Windows extensions ('*')
1368                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1369         }
1370
1371         /**
1372          * Helper for createLoaderURL()
1373          *
1374          * @since 1.24
1375          * @see makeLoaderQuery
1376          * @param ResourceLoaderContext $context
1377          * @param array $extraQuery
1378          * @return array
1379          */
1380         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1381                 return self::makeLoaderQuery(
1382                         $context->getModules(),
1383                         $context->getLanguage(),
1384                         $context->getSkin(),
1385                         $context->getUser(),
1386                         $context->getVersion(),
1387                         $context->getDebug(),
1388                         $context->getOnly(),
1389                         $context->getRequest()->getBool( 'printable' ),
1390                         $context->getRequest()->getBool( 'handheld' ),
1391                         $extraQuery
1392                 );
1393         }
1394
1395         /**
1396          * Build a query array (array representation of query string) for load.php. Helper
1397          * function for makeLoaderURL().
1398          *
1399          * @param array $modules
1400          * @param string $lang
1401          * @param string $skin
1402          * @param string $user
1403          * @param string $version
1404          * @param bool $debug
1405          * @param string $only
1406          * @param bool $printable
1407          * @param bool $handheld
1408          * @param array $extraQuery
1409          *
1410          * @return array
1411          */
1412         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1413                 $version = null, $debug = false, $only = null, $printable = false,
1414                 $handheld = false, $extraQuery = array()
1415         ) {
1416                 $query = array(
1417                         'modules' => self::makePackedModulesString( $modules ),
1418                         'lang' => $lang,
1419                         'skin' => $skin,
1420                         'debug' => $debug ? 'true' : 'false',
1421                 );
1422                 if ( $user !== null ) {
1423                         $query['user'] = $user;
1424                 }
1425                 if ( $version !== null ) {
1426                         $query['version'] = $version;
1427                 }
1428                 if ( $only !== null ) {
1429                         $query['only'] = $only;
1430                 }
1431                 if ( $printable ) {
1432                         $query['printable'] = 1;
1433                 }
1434                 if ( $handheld ) {
1435                         $query['handheld'] = 1;
1436                 }
1437                 $query += $extraQuery;
1438
1439                 // Make queries uniform in order
1440                 ksort( $query );
1441                 return $query;
1442         }
1443
1444         /**
1445          * Check a module name for validity.
1446          *
1447          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1448          * at most 255 bytes.
1449          *
1450          * @param string $moduleName Module name to check
1451          * @return bool Whether $moduleName is a valid module name
1452          */
1453         public static function isValidModuleName( $moduleName ) {
1454                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1455         }
1456
1457         /**
1458          * Returns LESS compiler set up for use with MediaWiki
1459          *
1460          * @param Config $config
1461          * @throws MWException
1462          * @since 1.22
1463          * @return lessc
1464          */
1465         public static function getLessCompiler( Config $config ) {
1466                 // When called from the installer, it is possible that a required PHP extension
1467                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1468                 // exception (caught by the installer) to prevent a fatal error later on.
1469                 if ( !function_exists( 'ctype_digit' ) ) {
1470                         throw new MWException( 'lessc requires the Ctype extension' );
1471                 }
1472
1473                 $less = new lessc();
1474                 $less->setPreserveComments( true );
1475                 $less->setVariables( self::getLessVars( $config ) );
1476                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1477                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1478                         $less->registerFunction( $name, $func );
1479                 }
1480                 return $less;
1481         }
1482
1483         /**
1484          * Get global LESS variables.
1485          *
1486          * @param Config $config
1487          * @since 1.22
1488          * @return array Map of variable names to string CSS values.
1489          */
1490         public static function getLessVars( Config $config ) {
1491                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1492                 // Sort by key to ensure consistent hashing for cache lookups.
1493                 ksort( $lessVars );
1494                 return $lessVars;
1495         }
1496 }