includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /**
  39          * Module name/ResourceLoaderModule object pairs
  40          * @var array
  41          */
  42         protected $modules = array();
  43
  44         /**
  45          * Associative array mapping module name to info associative array
  46          * @var array
  47          */
  48         protected $moduleInfos = array();
  49
  50         /** @var Config $config */
  51         private $config;
  52
  53         /**
  54          * Associative array mapping framework ids to a list of names of test suite modules
  55          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  56          * @var array
  57          */
  58         protected $testModuleNames = array();
  59
  60         /**
  61          * E.g. array( 'source-id' => 'http://.../load.php' )
  62          * @var array
  63          */
  64         protected $sources = array();
  65
  66         /**
  67          * Errors accumulated during current respond() call.
  68          * @var array
  69          */
  70         protected $errors = array();
  71
  72         /**
  73          * Load information stored in the database about modules.
  74          *
  75          * This method grabs modules dependencies from the database and updates modules
  76          * objects.
  77          *
  78          * This is not inside the module code because it is much faster to
  79          * request all of the information at once than it is to have each module
  80          * requests its own information. This sacrifice of modularity yields a substantial
  81          * performance improvement.
  82          *
  83          * @param array $modules List of module names to preload information for
  84          * @param ResourceLoaderContext $context Context to load the information within
  85          */
  86         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  87                 if ( !count( $modules ) ) {
  88                         // Or else Database*::select() will explode, plus it's cheaper!
  89                         return;
  90                 }
  91                 $dbr = wfGetDB( DB_SLAVE );
  92                 $skin = $context->getSkin();
  93                 $lang = $context->getLanguage();
  94
  95                 // Get file dependency information
  96                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  97                                 'md_module' => $modules,
  98                                 'md_skin' => $skin
  99                         ), __METHOD__
 100                 );
 101
 102                 // Set modules' dependencies
 103                 $modulesWithDeps = array();
 104                 foreach ( $res as $row ) {
 105                         $module = $this->getModule( $row->md_module );
 106                         if ( $module ) {
 107                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 108                                 $modulesWithDeps[] = $row->md_module;
 109                         }
 110                 }
 111
 112                 // Register the absence of a dependency row too
 113                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 114                         $module = $this->getModule( $name );
 115                         if ( $module ) {
 116                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 117                         }
 118                 }
 119
 120                 // Get message blob mtimes. Only do this for modules with messages
 121                 $modulesWithMessages = array();
 122                 foreach ( $modules as $name ) {
 123                         $module = $this->getModule( $name );
 124                         if ( $module && count( $module->getMessages() ) ) {
 125                                 $modulesWithMessages[] = $name;
 126                         }
 127                 }
 128                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 129                 if ( count( $modulesWithMessages ) ) {
 130                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 131                                         'mr_resource' => $modulesWithMessages,
 132                                         'mr_lang' => $lang
 133                                 ), __METHOD__
 134                         );
 135                         foreach ( $res as $row ) {
 136                                 $module = $this->getModule( $row->mr_resource );
 137                                 if ( $module ) {
 138                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 139                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 140                                 }
 141                         }
 142                 }
 143                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 144                         $module = $this->getModule( $name );
 145                         if ( $module ) {
 146                                 $module->setMsgBlobMtime( $lang, 1 );
 147                         }
 148                 }
 149         }
 150
 151         /**
 152          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 153          *
 154          * Available filters are:
 155          *
 156          *    - minify-js \see JavaScriptMinifier::minify
 157          *    - minify-css \see CSSMin::minify
 158          *
 159          * If $data is empty, only contains whitespace or the filter was unknown,
 160          * $data is returned unmodified.
 161          *
 162          * @param string $filter Name of filter to run
 163          * @param string $data Text to filter, such as JavaScript or CSS text
 164          * @param string $cacheReport Whether to include the cache key report
 165          * @return string Filtered data, or a comment containing an error message
 166          */
 167         public function filter( $filter, $data, $cacheReport = true ) {
 168
 169                 // For empty/whitespace-only data or for unknown filters, don't perform
 170                 // any caching or processing
 171                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 172                         return $data;
 173                 }
 174
 175                 // Try for cache hit
 176                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 177                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 178                 $cache = wfGetCache( CACHE_ANYTHING );
 179                 $cacheEntry = $cache->get( $key );
 180                 if ( is_string( $cacheEntry ) ) {
 181                         wfIncrStats( "rl-$filter-cache-hits" );
 182                         return $cacheEntry;
 183                 }
 184
 185                 $result = '';
 186                 // Run the filter - we've already verified one of these will work
 187                 try {
 188                         wfIncrStats( "rl-$filter-cache-misses" );
 189                         switch ( $filter ) {
 190                                 case 'minify-js':
 191                                         $result = JavaScriptMinifier::minify( $data,
 192                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 193                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 194                                         );
 195                                         if ( $cacheReport ) {
 196                                                 $result .= "\n/* cache key: $key */";
 197                                         }
 198                                         break;
 199                                 case 'minify-css':
 200                                         $result = CSSMin::minify( $data );
 201                                         if ( $cacheReport ) {
 202                                                 $result .= "\n/* cache key: $key */";
 203                                         }
 204                                         break;
 205                         }
 206
 207                         // Save filtered text to Memcached
 208                         $cache->set( $key, $result );
 209                 } catch ( Exception $e ) {
 210                         MWExceptionHandler::logException( $e );
 211                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 212                         $this->errors[] = self::formatExceptionNoComment( $e );
 213                 }
 214
 215
 216                 return $result;
 217         }
 218
 219         /* Methods */
 220
 221         /**
 222          * Register core modules and runs registration hooks.
 223          * @param Config|null $config
 224          */
 225         public function __construct( Config $config = null ) {
 226                 global $IP;
 227
 228
 229                 if ( $config === null ) {
 230                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 231                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 232                 }
 233
 234                 $this->config = $config;
 235
 236                 // Add 'local' source first
 237                 $this->addSource( 'local', wfScript( 'load' ) );
 238
 239                 // Add other sources
 240                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 241
 242                 // Register core modules
 243                 $this->register( include "$IP/resources/Resources.php" );
 244                 // Register extension modules
 245                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 246                 $this->register( $config->get( 'ResourceModules' ) );
 247
 248                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 249                         $this->registerTestModules();
 250                 }
 251
 252         }
 253
 254         /**
 255          * @return Config
 256          */
 257         public function getConfig() {
 258                 return $this->config;
 259         }
 260
 261         /**
 262          * Register a module with the ResourceLoader system.
 263          *
 264          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 265          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 266          *   this may also be a ResourceLoaderModule object. Optional when using
 267          *   multiple-registration calling style.
 268          * @throws MWException If a duplicate module registration is attempted
 269          * @throws MWException If a module name contains illegal characters (pipes or commas)
 270          * @throws MWException If something other than a ResourceLoaderModule is being registered
 271          * @return bool False if there were any errors, in which case one or more modules were
 272          *   not registered
 273          */
 274         public function register( $name, $info = null ) {
 275
 276                 // Allow multiple modules to be registered in one call
 277                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 278                 foreach ( $registrations as $name => $info ) {
 279                         // Disallow duplicate registrations
 280                         if ( isset( $this->moduleInfos[$name] ) ) {
 281                                 // A module has already been registered by this name
 282                                 throw new MWException(
 283                                         'ResourceLoader duplicate registration error. ' .
 284                                         'Another module has already been registered as ' . $name
 285                                 );
 286                         }
 287
 288                         // Check $name for validity
 289                         if ( !self::isValidModuleName( $name ) ) {
 290                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 291                                         . "see ResourceLoader::isValidModuleName()" );
 292                         }
 293
 294                         // Attach module
 295                         if ( $info instanceof ResourceLoaderModule ) {
 296                                 $this->moduleInfos[$name] = array( 'object' => $info );
 297                                 $info->setName( $name );
 298                                 $this->modules[$name] = $info;
 299                         } elseif ( is_array( $info ) ) {
 300                                 // New calling convention
 301                                 $this->moduleInfos[$name] = $info;
 302                         } else {
 303                                 throw new MWException(
 304                                         'ResourceLoader module info type error for module \'' . $name .
 305                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 306                                 );
 307                         }
 308
 309                         // Last-minute changes
 310
 311                         // Apply custom skin-defined styles to existing modules.
 312                         if ( $this->isFileModule( $name ) ) {
 313                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 314                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 315                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 316                                                 continue;
 317                                         }
 318
 319                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 320                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 321                                         if ( isset( $skinStyles[$name] ) ) {
 322                                                 $paths = (array)$skinStyles[$name];
 323                                                 $styleFiles = array();
 324                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 325                                                 $paths = (array)$skinStyles['+' . $name];
 326                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 327                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 328                                                         array();
 329                                         } else {
 330                                                 continue;
 331                                         }
 332
 333                                         // Add new file paths, remapping them to refer to our directories and not use settings
 334                                         // from the module we're modifying. These can come from the base definition or be defined
 335                                         // for each module.
 336                                         list( $localBasePath, $remoteBasePath ) =
 337                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 338                                         list( $localBasePath, $remoteBasePath ) =
 339                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 340
 341                                         foreach ( $paths as $path ) {
 342                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 343                                         }
 344
 345                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 346                                 }
 347                         }
 348                 }
 349
 350         }
 351
 352         /**
 353          */
 354         public function registerTestModules() {
 355                 global $IP;
 356
 357                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 358                         throw new MWException( 'Attempt to register JavaScript test modules '
 359                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 360                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 361                 }
 362
 363
 364                 // Get core test suites
 365                 $testModules = array();
 366                 $testModules['qunit'] = array();
 367                 // Get other test suites (e.g. from extensions)
 368                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 369
 370                 // Add the testrunner (which configures QUnit) to the dependencies.
 371                 // Since it must be ready before any of the test suites are executed.
 372                 foreach ( $testModules['qunit'] as &$module ) {
 373                         // Make sure all test modules are top-loading so that when QUnit starts
 374                         // on document-ready, it will run once and finish. If some tests arrive
 375                         // later (possibly after QUnit has already finished) they will be ignored.
 376                         $module['position'] = 'top';
 377                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 378                 }
 379
 380                 $testModules['qunit'] =
 381                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 382
 383                 foreach ( $testModules as $id => $names ) {
 384                         // Register test modules
 385                         $this->register( $testModules[$id] );
 386
 387                         // Keep track of their names so that they can be loaded together
 388                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 389                 }
 390
 391         }
 392
 393         /**
 394          * Add a foreign source of modules.
 395          *
 396          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 397          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 398          *  backwards-compatibility.
 399          * @throws MWException
 400          */
 401         public function addSource( $id, $loadUrl = null ) {
 402                 // Allow multiple sources to be registered in one call
 403                 if ( is_array( $id ) ) {
 404                         foreach ( $id as $key => $value ) {
 405                                 $this->addSource( $key, $value );
 406                         }
 407                         return;
 408                 }
 409
 410                 // Disallow duplicates
 411                 if ( isset( $this->sources[$id] ) ) {
 412                         throw new MWException(
 413                                 'ResourceLoader duplicate source addition error. ' .
 414                                 'Another source has already been registered as ' . $id
 415                         );
 416                 }
 417
 418                 // Pre 1.24 backwards-compatibility
 419                 if ( is_array( $loadUrl ) ) {
 420                         if ( !isset( $loadUrl['loadScript'] ) ) {
 421                                 throw new MWException(
 422                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 423                                 );
 424                         }
 425
 426                         $loadUrl = $loadUrl['loadScript'];
 427                 }
 428
 429                 $this->sources[$id] = $loadUrl;
 430         }
 431
 432         /**
 433          * Get a list of module names.
 434          *
 435          * @return array List of module names
 436          */
 437         public function getModuleNames() {
 438                 return array_keys( $this->moduleInfos );
 439         }
 440
 441         /**
 442          * Get a list of test module names for one (or all) frameworks.
 443          *
 444          * If the given framework id is unknkown, or if the in-object variable is not an array,
 445          * then it will return an empty array.
 446          *
 447          * @param string $framework Get only the test module names for one
 448          *   particular framework (optional)
 449          * @return array
 450          */
 451         public function getTestModuleNames( $framework = 'all' ) {
 452                 /** @todo api siteinfo prop testmodulenames modulenames */
 453                 if ( $framework == 'all' ) {
 454                         return $this->testModuleNames;
 455                 } elseif ( isset( $this->testModuleNames[$framework] )
 456                         && is_array( $this->testModuleNames[$framework] )
 457                 ) {
 458                         return $this->testModuleNames[$framework];
 459                 } else {
 460                         return array();
 461                 }
 462         }
 463
 464         /**
 465          * Get the ResourceLoaderModule object for a given module name.
 466          *
 467          * If an array of module parameters exists but a ResourceLoaderModule object has not
 468          * yet been instantiated, this method will instantiate and cache that object such that
 469          * subsequent calls simply return the same object.
 470          *
 471          * @param string $name Module name
 472          * @return ResourceLoaderModule|null If module has been registered, return a
 473          *  ResourceLoaderModule instance. Otherwise, return null.
 474          */
 475         public function getModule( $name ) {
 476                 if ( !isset( $this->modules[$name] ) ) {
 477                         if ( !isset( $this->moduleInfos[$name] ) ) {
 478                                 // No such module
 479                                 return null;
 480                         }
 481                         // Construct the requested object
 482                         $info = $this->moduleInfos[$name];
 483                         /** @var ResourceLoaderModule $object */
 484                         if ( isset( $info['object'] ) ) {
 485                                 // Object given in info array
 486                                 $object = $info['object'];
 487                         } else {
 488                                 if ( !isset( $info['class'] ) ) {
 489                                         $class = 'ResourceLoaderFileModule';
 490                                 } else {
 491                                         $class = $info['class'];
 492                                 }
 493                                 /** @var ResourceLoaderModule $object */
 494                                 $object = new $class( $info );
 495                                 $object->setConfig( $this->getConfig() );
 496                         }
 497                         $object->setName( $name );
 498                         $this->modules[$name] = $object;
 499                 }
 500
 501                 return $this->modules[$name];
 502         }
 503
 504         /**
 505          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 506          *
 507          * @param string $name Module name
 508          * @return bool
 509          */
 510         protected function isFileModule( $name ) {
 511                 if ( !isset( $this->moduleInfos[$name] ) ) {
 512                         return false;
 513                 }
 514                 $info = $this->moduleInfos[$name];
 515                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 516                         return false;
 517                 }
 518                 return true;
 519         }
 520
 521         /**
 522          * Get the list of sources.
 523          *
 524          * @return array Like array( id => load.php url, .. )
 525          */
 526         public function getSources() {
 527                 return $this->sources;
 528         }
 529
 530         /**
 531          * Get the URL to the load.php endpoint for the given
 532          * ResourceLoader source
 533          *
 534          * @since 1.24
 535          * @param string $source
 536          * @throws MWException On an invalid $source name
 537          * @return string
 538          */
 539         public function getLoadScript( $source ) {
 540                 if ( !isset( $this->sources[$source] ) ) {
 541                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 542                 }
 543                 return $this->sources[$source];
 544         }
 545
 546         /**
 547          * Output a response to a load request, including the content-type header.
 548          *
 549          * @param ResourceLoaderContext $context Context in which a response should be formed
 550          */
 551         public function respond( ResourceLoaderContext $context ) {
 552                 // Use file cache if enabled and available...
 553                 if ( $this->config->get( 'UseFileCache' ) ) {
 554                         $fileCache = ResourceFileCache::newFromContext( $context );
 555                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 556                                 return; // output handled
 557                         }
 558                 }
 559
 560                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 561                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 562                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 563                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 564                 // the whole thing in our own output buffer to be sure the active buffer
 565                 // doesn't use ob_gzhandler.
 566                 // See http://bugs.php.net/bug.php?id=36514
 567                 ob_start();
 568
 569
 570                 // Find out which modules are missing and instantiate the others
 571                 $modules = array();
 572                 $missing = array();
 573                 foreach ( $context->getModules() as $name ) {
 574                         $module = $this->getModule( $name );
 575                         if ( $module ) {
 576                                 // Do not allow private modules to be loaded from the web.
 577                                 // This is a security issue, see bug 34907.
 578                                 if ( $module->getGroup() === 'private' ) {
 579                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 580                                         $this->errors[] = "Cannot show private module \"$name\"";
 581                                         continue;
 582                                 }
 583                                 $modules[$name] = $module;
 584                         } else {
 585                                 $missing[] = $name;
 586                         }
 587                 }
 588
 589                 // Preload information needed to the mtime calculation below
 590                 try {
 591                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 592                 } catch ( Exception $e ) {
 593                         MWExceptionHandler::logException( $e );
 594                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 595                         $this->errors[] = self::formatExceptionNoComment( $e );
 596                 }
 597
 598
 599                 // To send Last-Modified and support If-Modified-Since, we need to detect
 600                 // the last modified time
 601                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 602                 foreach ( $modules as $module ) {
 603                         /**
 604                          * @var $module ResourceLoaderModule
 605                          */
 606                         try {
 607                                 // Calculate maximum modified time
 608                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 609                         } catch ( Exception $e ) {
 610                                 MWExceptionHandler::logException( $e );
 611                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 612                                 $this->errors[] = self::formatExceptionNoComment( $e );
 613                         }
 614                 }
 615
 616
 617                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 618                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 619                         return; // output handled (buffers cleared)
 620                 }
 621
 622                 // Generate a response
 623                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 624
 625                 // Capture any PHP warnings from the output buffer and append them to the
 626                 // error list if we're in debug mode.
 627                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 628                         $this->errors[] = $warnings;
 629                 }
 630
 631                 // Save response to file cache unless there are errors
 632                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 633                         // Cache single modules and images...and other requests if there are enough hits
 634                         if ( ResourceFileCache::useFileCache( $context ) ) {
 635                                 if ( $fileCache->isCacheWorthy() ) {
 636                                         $fileCache->saveText( $response );
 637                                 } else {
 638                                         $fileCache->incrMissesRecent( $context->getRequest() );
 639                                 }
 640                         }
 641                 }
 642
 643                 // Send content type and cache related headers
 644                 $this->sendResponseHeaders( $context, $mtime, (bool)$this->errors );
 645
 646                 // Remove the output buffer and output the response
 647                 ob_end_clean();
 648
 649                 if ( $context->getImageObj() && $this->errors ) {
 650                         // We can't show both the error messages and the response when it's an image.
 651                         $errorText = '';
 652                         foreach ( $this->errors as $error ) {
 653                                 $errorText .= $error . "\n";
 654                         }
 655                         $response = $errorText;
 656                 } elseif ( $this->errors ) {
 657                         // Prepend comments indicating errors
 658                         $errorText = '';
 659                         foreach ( $this->errors as $error ) {
 660                                 $errorText .= self::makeComment( $error );
 661                         }
 662                         $response = $errorText . $response;
 663                 }
 664
 665                 $this->errors = array();
 666                 echo $response;
 667
 668         }
 669
 670         /**
 671          * Send content type and last modified headers to the client.
 672          * @param ResourceLoaderContext $context
 673          * @param string $mtime TS_MW timestamp to use for last-modified
 674          * @param bool $errors Whether there are errors in the response
 675          * @return void
 676          */
 677         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 678                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 679                 // If a version wasn't specified we need a shorter expiry time for updates
 680                 // to propagate to clients quickly
 681                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 682                 if ( is_null( $context->getVersion() ) || $errors ) {
 683                         $maxage = $rlMaxage['unversioned']['client'];
 684                         $smaxage = $rlMaxage['unversioned']['server'];
 685                 // If a version was specified we can use a longer expiry time since changing
 686                 // version numbers causes cache misses
 687                 } else {
 688                         $maxage = $rlMaxage['versioned']['client'];
 689                         $smaxage = $rlMaxage['versioned']['server'];
 690                 }
 691                 if ( $context->getImageObj() ) {
 692                         // Output different headers if we're outputting textual errors.
 693                         if ( $errors ) {
 694                                 header( 'Content-Type: text/plain; charset=utf-8' );
 695                         } else {
 696                                 $context->getImageObj()->sendResponseHeaders( $context );
 697                         }
 698                 } elseif ( $context->getOnly() === 'styles' ) {
 699                         header( 'Content-Type: text/css; charset=utf-8' );
 700                         header( 'Access-Control-Allow-Origin: *' );
 701                 } else {
 702                         header( 'Content-Type: text/javascript; charset=utf-8' );
 703                 }
 704                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 705                 if ( $context->getDebug() ) {
 706                         // Do not cache debug responses
 707                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 708                         header( 'Pragma: no-cache' );
 709                 } else {
 710                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 711                         $exp = min( $maxage, $smaxage );
 712                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 713                 }
 714         }
 715
 716         /**
 717          * Respond with 304 Last Modified if appropiate.
 718          *
 719          * If there's an If-Modified-Since header, respond with a 304 appropriately
 720          * and clear out the output buffer. If the client cache is too old then do nothing.
 721          *
 722          * @param ResourceLoaderContext $context
 723          * @param string $mtime The TS_MW timestamp to check the header against
 724          * @return bool True if 304 header sent and output handled
 725          */
 726         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 727                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 728                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 729                 // so we get a valid timestamp.
 730                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 731                 // Never send 304s in debug mode
 732                 if ( $ims !== false && !$context->getDebug() ) {
 733                         $imsTS = strtok( $ims, ';' );
 734                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 735                                 // There's another bug in ob_gzhandler (see also the comment at
 736                                 // the top of this function) that causes it to gzip even empty
 737                                 // responses, meaning it's impossible to produce a truly empty
 738                                 // response (because the gzip header is always there). This is
 739                                 // a problem because 304 responses have to be completely empty
 740                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 741                                 // See also http://bugs.php.net/bug.php?id=51579
 742                                 // To work around this, we tear down all output buffering before
 743                                 // sending the 304.
 744                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 745
 746                                 header( 'HTTP/1.0 304 Not Modified' );
 747                                 header( 'Status: 304 Not Modified' );
 748                                 return true;
 749                         }
 750                 }
 751                 return false;
 752         }
 753
 754         /**
 755          * Send out code for a response from file cache if possible.
 756          *
 757          * @param ResourceFileCache $fileCache Cache object for this request URL
 758          * @param ResourceLoaderContext $context Context in which to generate a response
 759          * @return bool If this found a cache file and handled the response
 760          */
 761         protected function tryRespondFromFileCache(
 762                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 763         ) {
 764                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 765                 // Buffer output to catch warnings.
 766                 ob_start();
 767                 // Get the maximum age the cache can be
 768                 $maxage = is_null( $context->getVersion() )
 769                         ? $rlMaxage['unversioned']['server']
 770                         : $rlMaxage['versioned']['server'];
 771                 // Minimum timestamp the cache file must have
 772                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 773                 if ( !$good ) {
 774                         try { // RL always hits the DB on file cache miss...
 775                                 wfGetDB( DB_SLAVE );
 776                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 777                                 $good = $fileCache->isCacheGood(); // cache existence check
 778                         }
 779                 }
 780                 if ( $good ) {
 781                         $ts = $fileCache->cacheTimestamp();
 782                         // Send content type and cache headers
 783                         $this->sendResponseHeaders( $context, $ts, false );
 784                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 785                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 786                                 return false; // output handled (buffers cleared)
 787                         }
 788                         $response = $fileCache->fetchText();
 789                         // Capture any PHP warnings from the output buffer and append them to the
 790                         // response in a comment if we're in debug mode.
 791                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 792                                 $response = "/*\n$warnings\n*/\n" . $response;
 793                         }
 794                         // Remove the output buffer and output the response
 795                         ob_end_clean();
 796                         echo $response . "\n/* Cached {$ts} */";
 797                         return true; // cache hit
 798                 }
 799                 // Clear buffer
 800                 ob_end_clean();
 801
 802                 return false; // cache miss
 803         }
 804
 805         /**
 806          * Generate a CSS or JS comment block.
 807          *
 808          * Only use this for public data, not error message details.
 809          *
 810          * @param string $text
 811          * @return string
 812          */
 813         public static function makeComment( $text ) {
 814                 $encText = str_replace( '*/', '* /', $text );
 815                 return "/*\n$encText\n*/\n";
 816         }
 817
 818         /**
 819          * Handle exception display.
 820          *
 821          * @param Exception $e Exception to be shown to the user
 822          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 823          */
 824         public static function formatException( $e ) {
 825                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 826         }
 827
 828         /**
 829          * Handle exception display.
 830          *
 831          * @since 1.25
 832          * @param Exception $e Exception to be shown to the user
 833          * @return string Sanitized text that can be returned to the user
 834          */
 835         protected static function formatExceptionNoComment( $e ) {
 836                 global $wgShowExceptionDetails;
 837
 838                 if ( $wgShowExceptionDetails ) {
 839                         return $e->__toString();
 840                 } else {
 841                         return wfMessage( 'internalerror' )->text();
 842                 }
 843         }
 844
 845         /**
 846          * Generate code for a response.
 847          *
 848          * @param ResourceLoaderContext $context Context in which to generate a response
 849          * @param array $modules List of module objects keyed by module name
 850          * @param array $missing List of requested module names that are unregistered (optional)
 851          * @return string Response data
 852          */
 853         public function makeModuleResponse( ResourceLoaderContext $context,
 854                 array $modules, array $missing = array()
 855         ) {
 856                 $out = '';
 857                 $states = array();
 858
 859                 if ( !count( $modules ) && !count( $missing ) ) {
 860                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 861    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 862    no modules were requested. Max made me put this here. */";
 863                 }
 864
 865
 866                 $image = $context->getImageObj();
 867                 if ( $image ) {
 868                         $data = $image->getImageData( $context );
 869                         if ( $data === false ) {
 870                                 $data = '';
 871                                 $this->errors[] = 'Image generation failed';
 872                         }
 873                         return $data;
 874                 }
 875
 876                 // Pre-fetch blobs
 877                 if ( $context->shouldIncludeMessages() ) {
 878                         try {
 879                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 880                         } catch ( Exception $e ) {
 881                                 MWExceptionHandler::logException( $e );
 882                                 wfDebugLog(
 883                                         'resourceloader',
 884                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 885                                 );
 886                                 $this->errors[] = self::formatExceptionNoComment( $e );
 887                         }
 888                 } else {
 889                         $blobs = array();
 890                 }
 891
 892                 foreach ( $missing as $name ) {
 893                         $states[$name] = 'missing';
 894                 }
 895
 896                 // Generate output
 897                 $isRaw = false;
 898                 foreach ( $modules as $name => $module ) {
 899                         /**
 900                          * @var $module ResourceLoaderModule
 901                          */
 902
 903                         try {
 904                                 $scripts = '';
 905                                 if ( $context->shouldIncludeScripts() ) {
 906                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 907                                         // However, we can't do this if the module doesn't support it
 908                                         // We also can't do this if there is an only= parameter, because we have to give
 909                                         // the module a way to return a load.php URL without causing an infinite loop
 910                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 911                                                 $scripts = $module->getScriptURLsForDebug( $context );
 912                                         } else {
 913                                                 $scripts = $module->getScript( $context );
 914                                                 // rtrim() because there are usually a few line breaks
 915                                                 // after the last ';'. A new line at EOF, a new line
 916                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 917                                                 if ( is_string( $scripts )
 918                                                         && strlen( $scripts )
 919                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 920                                                 ) {
 921                                                         // Append semicolon to prevent weird bugs caused by files not
 922                                                         // terminating their statements right (bug 27054)
 923                                                         $scripts .= ";\n";
 924                                                 }
 925                                         }
 926                                 }
 927                                 // Styles
 928                                 $styles = array();
 929                                 if ( $context->shouldIncludeStyles() ) {
 930                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 931                                         // that don't *have* any stylesheets (bug 38024).
 932                                         $stylePairs = $module->getStyles( $context );
 933                                         if ( count( $stylePairs ) ) {
 934                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 935                                                 // See comment near shouldIncludeScripts() for more details
 936                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 937                                                         $styles = array(
 938                                                                 'url' => $module->getStyleURLsForDebug( $context )
 939                                                         );
 940                                                 } else {
 941                                                         // Minify CSS before embedding in mw.loader.implement call
 942                                                         // (unless in debug mode)
 943                                                         if ( !$context->getDebug() ) {
 944                                                                 foreach ( $stylePairs as $media => $style ) {
 945                                                                         // Can be either a string or an array of strings.
 946                                                                         if ( is_array( $style ) ) {
 947                                                                                 $stylePairs[$media] = array();
 948                                                                                 foreach ( $style as $cssText ) {
 949                                                                                         if ( is_string( $cssText ) ) {
 950                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 951                                                                                         }
 952                                                                                 }
 953                                                                         } elseif ( is_string( $style ) ) {
 954                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 955                                                                         }
 956                                                                 }
 957                                                         }
 958                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 959                                                         $styles = array(
 960                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 961                                                         );
 962                                                 }
 963                                         }
 964                                 }
 965
 966                                 // Messages
 967                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 968
 969                                 // Append output
 970                                 switch ( $context->getOnly() ) {
 971                                         case 'scripts':
 972                                                 if ( is_string( $scripts ) ) {
 973                                                         // Load scripts raw...
 974                                                         $out .= $scripts;
 975                                                 } elseif ( is_array( $scripts ) ) {
 976                                                         // ...except when $scripts is an array of URLs
 977                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 978                                                 }
 979                                                 break;
 980                                         case 'styles':
 981                                                 // We no longer seperate into media, they are all combined now with
 982                                                 // custom media type groups into @media .. {} sections as part of the css string.
 983                                                 // Module returns either an empty array or a numerical array with css strings.
 984                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 985                                                 break;
 986                                         case 'messages':
 987                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 988                                                 break;
 989                                         case 'templates':
 990                                                 $out .= Xml::encodeJsCall(
 991                                                         'mw.templates.set',
 992                                                         array( $name, (object)$module->getTemplates() ),
 993                                                         ResourceLoader::inDebugMode()
 994                                                 );
 995                                                 break;
 996                                         default:
 997                                                 $out .= self::makeLoaderImplementScript(
 998                                                         $name,
 999                                                         $scripts,
1000                                                         $styles,
1001                                                         new XmlJsCode( $messagesBlob ),
1002                                                         $module->getTemplates()
1003                                                 );
1004                                                 break;
1005                                 }
1006                         } catch ( Exception $e ) {
1007                                 MWExceptionHandler::logException( $e );
1008                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
1009                                 $this->errors[] = self::formatExceptionNoComment( $e );
1010
1011                                 // Respond to client with error-state instead of module implementation
1012                                 $states[$name] = 'error';
1013                                 unset( $modules[$name] );
1014                         }
1015                         $isRaw |= $module->isRaw();
1016                 }
1017
1018                 // Update module states
1019                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1020                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1021                                 // Set the state of modules loaded as only scripts to ready as
1022                                 // they don't have an mw.loader.implement wrapper that sets the state
1023                                 foreach ( $modules as $name => $module ) {
1024                                         $states[$name] = 'ready';
1025                                 }
1026                         }
1027
1028                         // Set the state of modules we didn't respond to with mw.loader.implement
1029                         if ( count( $states ) ) {
1030                                 $out .= self::makeLoaderStateScript( $states );
1031                         }
1032                 } else {
1033                         if ( count( $states ) ) {
1034                                 $this->errors[] = 'Problematic modules: ' .
1035                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1036                         }
1037                 }
1038
1039                 if ( !$context->getDebug() ) {
1040                         if ( $context->getOnly() === 'styles' ) {
1041                                 $out = $this->filter( 'minify-css', $out );
1042                         } else {
1043                                 $out = $this->filter( 'minify-js', $out );
1044                         }
1045                 }
1046
1047                 return $out;
1048         }
1049
1050         /* Static Methods */
1051
1052         /**
1053          * Return JS code that calls mw.loader.implement with given module properties.
1054          *
1055          * @param string $name Module name
1056          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1057          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1058          *   to CSS files keyed by media type
1059          * @param mixed $messages List of messages associated with this module. May either be an
1060          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1061          *   the same data, wrapped in an XmlJsCode object.
1062          * @param array $templates Keys are name of templates and values are the source of
1063          *   the template.
1064          * @throws MWException
1065          * @return string
1066          */
1067         public static function makeLoaderImplementScript( $name, $scripts, $styles,
1068                 $messages, $templates
1069         ) {
1070                 if ( is_string( $scripts ) ) {
1071                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1072                 } elseif ( !is_array( $scripts ) ) {
1073                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1074                 }
1075
1076                 return Xml::encodeJsCall(
1077                         'mw.loader.implement',
1078                         array(
1079                                 $name,
1080                                 $scripts,
1081                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1082                                 // Although these variables are associative arrays, which become javascript
1083                                 // objects through json_encode. In many cases they will be empty arrays, and
1084                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1085                                 // output javascript "[]" instead of "{}". This fixes that.
1086                                 (object)$styles,
1087                                 (object)$messages,
1088                                 (object)$templates,
1089                         ),
1090                         ResourceLoader::inDebugMode()
1091                 );
1092         }
1093
1094         /**
1095          * Returns JS code which, when called, will register a given list of messages.
1096          *
1097          * @param mixed $messages Either an associative array mapping message key to value, or a
1098          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1099          * @return string
1100          */
1101         public static function makeMessageSetScript( $messages ) {
1102                 return Xml::encodeJsCall(
1103                         'mw.messages.set',
1104                         array( (object)$messages ),
1105                         ResourceLoader::inDebugMode()
1106                 );
1107         }
1108
1109         /**
1110          * Combines an associative array mapping media type to CSS into a
1111          * single stylesheet with "@media" blocks.
1112          *
1113          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1114          * @return array
1115          */
1116         public static function makeCombinedStyles( array $stylePairs ) {
1117                 $out = array();
1118                 foreach ( $stylePairs as $media => $styles ) {
1119                         // ResourceLoaderFileModule::getStyle can return the styles
1120                         // as a string or an array of strings. This is to allow separation in
1121                         // the front-end.
1122                         $styles = (array)$styles;
1123                         foreach ( $styles as $style ) {
1124                                 $style = trim( $style );
1125                                 // Don't output an empty "@media print { }" block (bug 40498)
1126                                 if ( $style !== '' ) {
1127                                         // Transform the media type based on request params and config
1128                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1129                                         $media = OutputPage::transformCssMedia( $media );
1130
1131                                         if ( $media === '' || $media == 'all' ) {
1132                                                 $out[] = $style;
1133                                         } elseif ( is_string( $media ) ) {
1134                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1135                                         }
1136                                         // else: skip
1137                                 }
1138                         }
1139                 }
1140                 return $out;
1141         }
1142
1143         /**
1144          * Returns a JS call to mw.loader.state, which sets the state of a
1145          * module or modules to a given value. Has two calling conventions:
1146          *
1147          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1148          *         Set the state of a single module called $name to $state
1149          *
1150          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1151          *         Set the state of modules with the given names to the given states
1152          *
1153          * @param string $name
1154          * @param string $state
1155          * @return string
1156          */
1157         public static function makeLoaderStateScript( $name, $state = null ) {
1158                 if ( is_array( $name ) ) {
1159                         return Xml::encodeJsCall(
1160                                 'mw.loader.state',
1161                                 array( $name ),
1162                                 ResourceLoader::inDebugMode()
1163                         );
1164                 } else {
1165                         return Xml::encodeJsCall(
1166                                 'mw.loader.state',
1167                                 array( $name, $state ),
1168                                 ResourceLoader::inDebugMode()
1169                         );
1170                 }
1171         }
1172
1173         /**
1174          * Returns JS code which calls the script given by $script. The script will
1175          * be called with local variables name, version, dependencies and group,
1176          * which will have values corresponding to $name, $version, $dependencies
1177          * and $group as supplied.
1178          *
1179          * @param string $name Module name
1180          * @param int $version Module version number as a timestamp
1181          * @param array $dependencies List of module names on which this module depends
1182          * @param string $group Group which the module is in.
1183          * @param string $source Source of the module, or 'local' if not foreign.
1184          * @param string $script JavaScript code
1185          * @return string
1186          */
1187         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1188                 $group, $source, $script
1189         ) {
1190                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1191                 return Xml::encodeJsCall(
1192                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1193                         array( $name, $version, $dependencies, $group, $source ),
1194                         ResourceLoader::inDebugMode()
1195                 );
1196         }
1197
1198         /**
1199          * Remove empty values from the end of an array.
1200          *
1201          * Values considered empty:
1202          *
1203          * - null
1204          * - empty array
1205          *
1206          * @param Array $array
1207          */
1208         private static function trimArray( Array &$array ) {
1209                 $i = count( $array );
1210                 while ( $i-- ) {
1211                         if ( $array[$i] === null || $array[$i] === array() ) {
1212                                 unset( $array[$i] );
1213                         } else {
1214                                 break;
1215                         }
1216                 }
1217         }
1218
1219         /**
1220          * Returns JS code which calls mw.loader.register with the given
1221          * parameters. Has three calling conventions:
1222          *
1223          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1224          *        $dependencies, $group, $source, $skip
1225          *     ):
1226          *        Register a single module.
1227          *
1228          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1229          *        Register modules with the given names.
1230          *
1231          *   - ResourceLoader::makeLoaderRegisterScript( array(
1232          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1233          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1234          *        ...
1235          *     ) ):
1236          *        Registers modules with the given names and parameters.
1237          *
1238          * @param string $name Module name
1239          * @param int $version Module version number as a timestamp
1240          * @param array $dependencies List of module names on which this module depends
1241          * @param string $group Group which the module is in
1242          * @param string $source Source of the module, or 'local' if not foreign
1243          * @param string $skip Script body of the skip function
1244          * @return string
1245          */
1246         public static function makeLoaderRegisterScript( $name, $version = null,
1247                 $dependencies = null, $group = null, $source = null, $skip = null
1248         ) {
1249                 if ( is_array( $name ) ) {
1250                         // Build module name index
1251                         $index = array();
1252                         foreach ( $name as $i => &$module ) {
1253                                 $index[$module[0]] = $i;
1254                         }
1255
1256                         // Transform dependency names into indexes when possible, they will be resolved by
1257                         // mw.loader.register on the other end
1258                         foreach ( $name as &$module ) {
1259                                 if ( isset( $module[2] ) ) {
1260                                         foreach ( $module[2] as &$dependency ) {
1261                                                 if ( isset( $index[$dependency] ) ) {
1262                                                         $dependency = $index[$dependency];
1263                                                 }
1264                                         }
1265                                 }
1266                         }
1267
1268                         array_walk( $name, array( 'self', 'trimArray' ) );
1269
1270                         return Xml::encodeJsCall(
1271                                 'mw.loader.register',
1272                                 array( $name ),
1273                                 ResourceLoader::inDebugMode()
1274                         );
1275                 } else {
1276                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1277                         self::trimArray( $registration );
1278                         return Xml::encodeJsCall(
1279                                 'mw.loader.register',
1280                                 $registration,
1281                                 ResourceLoader::inDebugMode()
1282                         );
1283                 }
1284         }
1285
1286         /**
1287          * Returns JS code which calls mw.loader.addSource() with the given
1288          * parameters. Has two calling conventions:
1289          *
1290          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1291          *       Register a single source
1292          *
1293          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1294          *       Register sources with the given IDs and properties.
1295          *
1296          * @param string $id Source ID
1297          * @param array $properties Source properties (see addSource())
1298          * @return string
1299          */
1300         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1301                 if ( is_array( $id ) ) {
1302                         return Xml::encodeJsCall(
1303                                 'mw.loader.addSource',
1304                                 array( $id ),
1305                                 ResourceLoader::inDebugMode()
1306                         );
1307                 } else {
1308                         return Xml::encodeJsCall(
1309                                 'mw.loader.addSource',
1310                                 array( $id, $properties ),
1311                                 ResourceLoader::inDebugMode()
1312                         );
1313                 }
1314         }
1315
1316         /**
1317          * Returns JS code which runs given JS code if the client-side framework is
1318          * present.
1319          *
1320          * @param string $script JavaScript code
1321          * @return string
1322          */
1323         public static function makeLoaderConditionalScript( $script ) {
1324                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1325         }
1326
1327         /**
1328          * Returns JS code which will set the MediaWiki configuration array to
1329          * the given value.
1330          *
1331          * @param array $configuration List of configuration values keyed by variable name
1332          * @return string
1333          */
1334         public static function makeConfigSetScript( array $configuration ) {
1335                 return Xml::encodeJsCall(
1336                         'mw.config.set',
1337                         array( $configuration ),
1338                         ResourceLoader::inDebugMode()
1339                 );
1340         }
1341
1342         /**
1343          * Convert an array of module names to a packed query string.
1344          *
1345          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1346          * becomes 'foo.bar,baz|bar.baz,quux'
1347          * @param array $modules List of module names (strings)
1348          * @return string Packed query string
1349          */
1350         public static function makePackedModulesString( $modules ) {
1351                 $groups = array(); // array( prefix => array( suffixes ) )
1352                 foreach ( $modules as $module ) {
1353                         $pos = strrpos( $module, '.' );
1354                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1355                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1356                         $groups[$prefix][] = $suffix;
1357                 }
1358
1359                 $arr = array();
1360                 foreach ( $groups as $prefix => $suffixes ) {
1361                         $p = $prefix === '' ? '' : $prefix . '.';
1362                         $arr[] = $p . implode( ',', $suffixes );
1363                 }
1364                 $str = implode( '|', $arr );
1365                 return $str;
1366         }
1367
1368         /**
1369          * Determine whether debug mode was requested
1370          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1371          * @return bool
1372          */
1373         public static function inDebugMode() {
1374                 if ( self::$debugMode === null ) {
1375                         global $wgRequest, $wgResourceLoaderDebug;
1376                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1377                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1378                         );
1379                 }
1380                 return self::$debugMode;
1381         }
1382
1383         /**
1384          * Reset static members used for caching.
1385          *
1386          * Global state and $wgRequest are evil, but we're using it right
1387          * now and sometimes we need to be able to force ResourceLoader to
1388          * re-evaluate the context because it has changed (e.g. in the test suite).
1389          */
1390         public static function clearCache() {
1391                 self::$debugMode = null;
1392         }
1393
1394         /**
1395          * Build a load.php URL
1396          *
1397          * @since 1.24
1398          * @param string $source Name of the ResourceLoader source
1399          * @param ResourceLoaderContext $context
1400          * @param array $extraQuery
1401          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1402          */
1403         public function createLoaderURL( $source, ResourceLoaderContext $context,
1404                 $extraQuery = array()
1405         ) {
1406                 $query = self::createLoaderQuery( $context, $extraQuery );
1407                 $script = $this->getLoadScript( $source );
1408
1409                 // Prevent the IE6 extension check from being triggered (bug 28840)
1410                 // by appending a character that's invalid in Windows extensions ('*')
1411                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1412         }
1413
1414         /**
1415          * Build a load.php URL
1416          * @deprecated since 1.24, use createLoaderURL instead
1417          * @param array $modules Array of module names (strings)
1418          * @param string $lang Language code
1419          * @param string $skin Skin name
1420          * @param string|null $user User name. If null, the &user= parameter is omitted
1421          * @param string|null $version Versioning timestamp
1422          * @param bool $debug Whether the request should be in debug mode
1423          * @param string|null $only &only= parameter
1424          * @param bool $printable Printable mode
1425          * @param bool $handheld Handheld mode
1426          * @param array $extraQuery Extra query parameters to add
1427          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1428          */
1429         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1430                 $version = null, $debug = false, $only = null, $printable = false,
1431                 $handheld = false, $extraQuery = array()
1432         ) {
1433                 global $wgLoadScript;
1434
1435                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1436                         $only, $printable, $handheld, $extraQuery
1437                 );
1438
1439                 // Prevent the IE6 extension check from being triggered (bug 28840)
1440                 // by appending a character that's invalid in Windows extensions ('*')
1441                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1442         }
1443
1444         /**
1445          * Helper for createLoaderURL()
1446          *
1447          * @since 1.24
1448          * @see makeLoaderQuery
1449          * @param ResourceLoaderContext $context
1450          * @param array $extraQuery
1451          * @return array
1452          */
1453         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1454                 return self::makeLoaderQuery(
1455                         $context->getModules(),
1456                         $context->getLanguage(),
1457                         $context->getSkin(),
1458                         $context->getUser(),
1459                         $context->getVersion(),
1460                         $context->getDebug(),
1461                         $context->getOnly(),
1462                         $context->getRequest()->getBool( 'printable' ),
1463                         $context->getRequest()->getBool( 'handheld' ),
1464                         $extraQuery
1465                 );
1466         }
1467
1468         /**
1469          * Build a query array (array representation of query string) for load.php. Helper
1470          * function for makeLoaderURL().
1471          *
1472          * @param array $modules
1473          * @param string $lang
1474          * @param string $skin
1475          * @param string $user
1476          * @param string $version
1477          * @param bool $debug
1478          * @param string $only
1479          * @param bool $printable
1480          * @param bool $handheld
1481          * @param array $extraQuery
1482          *
1483          * @return array
1484          */
1485         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1486                 $version = null, $debug = false, $only = null, $printable = false,
1487                 $handheld = false, $extraQuery = array()
1488         ) {
1489                 $query = array(
1490                         'modules' => self::makePackedModulesString( $modules ),
1491                         'lang' => $lang,
1492                         'skin' => $skin,
1493                         'debug' => $debug ? 'true' : 'false',
1494                 );
1495                 if ( $user !== null ) {
1496                         $query['user'] = $user;
1497                 }
1498                 if ( $version !== null ) {
1499                         $query['version'] = $version;
1500                 }
1501                 if ( $only !== null ) {
1502                         $query['only'] = $only;
1503                 }
1504                 if ( $printable ) {
1505                         $query['printable'] = 1;
1506                 }
1507                 if ( $handheld ) {
1508                         $query['handheld'] = 1;
1509                 }
1510                 $query += $extraQuery;
1511
1512                 // Make queries uniform in order
1513                 ksort( $query );
1514                 return $query;
1515         }
1516
1517         /**
1518          * Check a module name for validity.
1519          *
1520          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1521          * at most 255 bytes.
1522          *
1523          * @param string $moduleName Module name to check
1524          * @return bool Whether $moduleName is a valid module name
1525          */
1526         public static function isValidModuleName( $moduleName ) {
1527                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1528         }
1529
1530         /**
1531          * Returns LESS compiler set up for use with MediaWiki
1532          *
1533          * @param Config $config
1534          * @throws MWException
1535          * @since 1.22
1536          * @return lessc
1537          */
1538         public static function getLessCompiler( Config $config ) {
1539                 // When called from the installer, it is possible that a required PHP extension
1540                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1541                 // exception (caught by the installer) to prevent a fatal error later on.
1542                 if ( !class_exists( 'lessc' ) ) {
1543                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1544                 }
1545                 if ( !function_exists( 'ctype_digit' ) ) {
1546                         throw new MWException( 'lessc requires the Ctype extension' );
1547                 }
1548
1549                 $less = new lessc();
1550                 $less->setPreserveComments( true );
1551                 $less->setVariables( self::getLessVars( $config ) );
1552                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1553                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1554                         $less->registerFunction( $name, $func );
1555                 }
1556                 return $less;
1557         }
1558
1559         /**
1560          * Get global LESS variables.
1561          *
1562          * @param Config $config
1563          * @since 1.22
1564          * @return array Map of variable names to string CSS values.
1565          */
1566         public static function getLessVars( Config $config ) {
1567                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1568                 // Sort by key to ensure consistent hashing for cache lookups.
1569                 ksort( $lessVars );
1570                 return $lessVars;
1571         }
1572 }