includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var array */
  36         protected static $requiredSourceProperties = array( 'loadScript' );
  37
  38         /** @var bool */
  39         protected static $debugMode = null;
  40
  41         /** @var array Module name/ResourceLoaderModule object pairs */
  42         protected $modules = array();
  43
  44         /** @var array Associative array mapping module name to info associative array */
  45         protected $moduleInfos = array();
  46
  47         /**
  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' => array( 'loadScript' => '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                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 156                 wfProfileIn( __METHOD__ );
 157
 158                 // For empty/whitespace-only data or for unknown filters, don't perform
 159                 // any caching or processing
 160                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 161                         wfProfileOut( __METHOD__ );
 162                         return $data;
 163                 }
 164
 165                 // Try for cache hit
 166                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 167                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 168                 $cache = wfGetCache( CACHE_ANYTHING );
 169                 $cacheEntry = $cache->get( $key );
 170                 if ( is_string( $cacheEntry ) ) {
 171                         wfIncrStats( "rl-$filter-cache-hits" );
 172                         wfProfileOut( __METHOD__ );
 173                         return $cacheEntry;
 174                 }
 175
 176                 $result = '';
 177                 // Run the filter - we've already verified one of these will work
 178                 try {
 179                         wfIncrStats( "rl-$filter-cache-misses" );
 180                         switch ( $filter ) {
 181                                 case 'minify-js':
 182                                         $result = JavaScriptMinifier::minify( $data,
 183                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 184                                                 $wgResourceLoaderMinifierMaxLineLength
 185                                         );
 186                                         if ( $cacheReport ) {
 187                                                 $result .= "\n/* cache key: $key */";
 188                                         }
 189                                         break;
 190                                 case 'minify-css':
 191                                         $result = CSSMin::minify( $data );
 192                                         if ( $cacheReport ) {
 193                                                 $result .= "\n/* cache key: $key */";
 194                                         }
 195                                         break;
 196                         }
 197
 198                         // Save filtered text to Memcached
 199                         $cache->set( $key, $result );
 200                 } catch ( Exception $e ) {
 201                         MWExceptionHandler::logException( $e );
 202                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 203                         $this->hasErrors = true;
 204                         // Return exception as a comment
 205                         $result = self::formatException( $e );
 206                 }
 207
 208                 wfProfileOut( __METHOD__ );
 209
 210                 return $result;
 211         }
 212
 213         /* Methods */
 214
 215         /**
 216          * Register core modules and runs registration hooks.
 217          */
 218         public function __construct() {
 219                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript, $wgEnableJavaScriptTest;
 220
 221                 wfProfileIn( __METHOD__ );
 222
 223                 // Add 'local' source first
 224                 $this->addSource(
 225                         'local',
 226                         array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) )
 227                 );
 228
 229                 // Add other sources
 230                 $this->addSource( $wgResourceLoaderSources );
 231
 232                 // Register core modules
 233                 $this->register( include "$IP/resources/Resources.php" );
 234                 // Register extension modules
 235                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 236                 $this->register( $wgResourceModules );
 237
 238                 if ( $wgEnableJavaScriptTest === true ) {
 239                         $this->registerTestModules();
 240                 }
 241
 242                 wfProfileOut( __METHOD__ );
 243         }
 244
 245         /**
 246          * Register a module with the ResourceLoader system.
 247          *
 248          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 249          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 250          *   this may also be a ResourceLoaderModule object. Optional when using
 251          *   multiple-registration calling style.
 252          * @throws MWException If a duplicate module registration is attempted
 253          * @throws MWException If a module name contains illegal characters (pipes or commas)
 254          * @throws MWException If something other than a ResourceLoaderModule is being registered
 255          * @return bool False if there were any errors, in which case one or more modules were
 256          *   not registered
 257          */
 258         public function register( $name, $info = null ) {
 259                 wfProfileIn( __METHOD__ );
 260
 261                 // Allow multiple modules to be registered in one call
 262                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 263                 foreach ( $registrations as $name => $info ) {
 264                         // Disallow duplicate registrations
 265                         if ( isset( $this->moduleInfos[$name] ) ) {
 266                                 wfProfileOut( __METHOD__ );
 267                                 // A module has already been registered by this name
 268                                 throw new MWException(
 269                                         'ResourceLoader duplicate registration error. ' .
 270                                         'Another module has already been registered as ' . $name
 271                                 );
 272                         }
 273
 274                         // Check $name for validity
 275                         if ( !self::isValidModuleName( $name ) ) {
 276                                 wfProfileOut( __METHOD__ );
 277                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 278                                         . "see ResourceLoader::isValidModuleName()" );
 279                         }
 280
 281                         // Attach module
 282                         if ( $info instanceof ResourceLoaderModule ) {
 283                                 $this->moduleInfos[$name] = array( 'object' => $info );
 284                                 $info->setName( $name );
 285                                 $this->modules[$name] = $info;
 286                         } elseif ( is_array( $info ) ) {
 287                                 // New calling convention
 288                                 $this->moduleInfos[$name] = $info;
 289                         } else {
 290                                 wfProfileOut( __METHOD__ );
 291                                 throw new MWException(
 292                                         'ResourceLoader module info type error for module \'' . $name .
 293                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 294                                 );
 295                         }
 296                 }
 297
 298                 wfProfileOut( __METHOD__ );
 299         }
 300
 301         /**
 302          */
 303         public function registerTestModules() {
 304                 global $IP, $wgEnableJavaScriptTest;
 305
 306                 if ( $wgEnableJavaScriptTest !== true ) {
 307                         throw new MWException( 'Attempt to register JavaScript test modules '
 308                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 309                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 310                 }
 311
 312                 wfProfileIn( __METHOD__ );
 313
 314                 // Get core test suites
 315                 $testModules = array();
 316                 $testModules['qunit'] = array();
 317                 // Get other test suites (e.g. from extensions)
 318                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 319
 320                 // Add the testrunner (which configures QUnit) to the dependencies.
 321                 // Since it must be ready before any of the test suites are executed.
 322                 foreach ( $testModules['qunit'] as &$module ) {
 323                         // Make sure all test modules are top-loading so that when QUnit starts
 324                         // on document-ready, it will run once and finish. If some tests arrive
 325                         // later (possibly after QUnit has already finished) they will be ignored.
 326                         $module['position'] = 'top';
 327                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 328                 }
 329
 330                 $testModules['qunit'] =
 331                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 332
 333                 foreach ( $testModules as $id => $names ) {
 334                         // Register test modules
 335                         $this->register( $testModules[$id] );
 336
 337                         // Keep track of their names so that they can be loaded together
 338                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 339                 }
 340
 341                 wfProfileOut( __METHOD__ );
 342         }
 343
 344         /**
 345          * Add a foreign source of modules.
 346          *
 347          * Source properties:
 348          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 349          *
 350          * @param mixed $id Source ID (string), or array( id1 => props1, id2 => props2, ... )
 351          * @param array $properties Source properties
 352          * @throws MWException
 353          */
 354         public function addSource( $id, $properties = null ) {
 355                 // Allow multiple sources to be registered in one call
 356                 if ( is_array( $id ) ) {
 357                         foreach ( $id as $key => $value ) {
 358                                 $this->addSource( $key, $value );
 359                         }
 360                         return;
 361                 }
 362
 363                 // Disallow duplicates
 364                 if ( isset( $this->sources[$id] ) ) {
 365                         throw new MWException(
 366                                 'ResourceLoader duplicate source addition error. ' .
 367                                 'Another source has already been registered as ' . $id
 368                         );
 369                 }
 370
 371                 // Validate properties
 372                 foreach ( self::$requiredSourceProperties as $prop ) {
 373                         if ( !isset( $properties[$prop] ) ) {
 374                                 throw new MWException( "Required property $prop missing from source ID $id" );
 375                         }
 376                 }
 377
 378                 $this->sources[$id] = $properties;
 379         }
 380
 381         /**
 382          * Get a list of module names.
 383          *
 384          * @return array List of module names
 385          */
 386         public function getModuleNames() {
 387                 return array_keys( $this->moduleInfos );
 388         }
 389
 390         /**
 391          * Get a list of test module names for one (or all) frameworks.
 392          *
 393          * If the given framework id is unknkown, or if the in-object variable is not an array,
 394          * then it will return an empty array.
 395          *
 396          * @param string $framework Get only the test module names for one
 397          *   particular framework (optional)
 398          * @return array
 399          */
 400         public function getTestModuleNames( $framework = 'all' ) {
 401                 /** @todo api siteinfo prop testmodulenames modulenames */
 402                 if ( $framework == 'all' ) {
 403                         return $this->testModuleNames;
 404                 } elseif ( isset( $this->testModuleNames[$framework] )
 405                         && is_array( $this->testModuleNames[$framework] )
 406                 ) {
 407                         return $this->testModuleNames[$framework];
 408                 } else {
 409                         return array();
 410                 }
 411         }
 412
 413         /**
 414          * Get the ResourceLoaderModule object for a given module name.
 415          *
 416          * If an array of module parameters exists but a ResourceLoaderModule object has not
 417          * yet been instantiated, this method will instantiate and cache that object such that
 418          * subsequent calls simply return the same object.
 419          *
 420          * @param string $name Module name
 421          * @return ResourceLoaderModule|null If module has been registered, return a
 422          *  ResourceLoaderModule instance. Otherwise, return null.
 423          */
 424         public function getModule( $name ) {
 425                 if ( !isset( $this->modules[$name] ) ) {
 426                         if ( !isset( $this->moduleInfos[$name] ) ) {
 427                                 // No such module
 428                                 return null;
 429                         }
 430                         // Construct the requested object
 431                         $info = $this->moduleInfos[$name];
 432                         /** @var ResourceLoaderModule $object */
 433                         if ( isset( $info['object'] ) ) {
 434                                 // Object given in info array
 435                                 $object = $info['object'];
 436                         } else {
 437                                 if ( !isset( $info['class'] ) ) {
 438                                         $class = 'ResourceLoaderFileModule';
 439                                 } else {
 440                                         $class = $info['class'];
 441                                 }
 442                                 $object = new $class( $info );
 443                         }
 444                         $object->setName( $name );
 445                         $this->modules[$name] = $object;
 446                 }
 447
 448                 return $this->modules[$name];
 449         }
 450
 451         /**
 452          * Get the list of sources.
 453          *
 454          * @return array Like array( id => array of properties, .. )
 455          */
 456         public function getSources() {
 457                 return $this->sources;
 458         }
 459
 460         /**
 461          * Get the URL to the load.php endpoint for the given
 462          * ResourceLoader source
 463          *
 464          * @since 1.24
 465          * @param string $source
 466          * @throws MWException on an invalid $source name
 467          * @return string
 468          */
 469         public function getLoadScript( $source ) {
 470                 if ( !isset( $this->sources[$source] ) ) {
 471                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 472                 }
 473                 return $this->sources[$source]['loadScript'];
 474         }
 475
 476         /**
 477          * Output a response to a load request, including the content-type header.
 478          *
 479          * @param ResourceLoaderContext $context Context in which a response should be formed
 480          */
 481         public function respond( ResourceLoaderContext $context ) {
 482                 global $wgCacheEpoch, $wgUseFileCache;
 483
 484                 // Use file cache if enabled and available...
 485                 if ( $wgUseFileCache ) {
 486                         $fileCache = ResourceFileCache::newFromContext( $context );
 487                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 488                                 return; // output handled
 489                         }
 490                 }
 491
 492                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 493                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 494                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 495                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 496                 // the whole thing in our own output buffer to be sure the active buffer
 497                 // doesn't use ob_gzhandler.
 498                 // See http://bugs.php.net/bug.php?id=36514
 499                 ob_start();
 500
 501                 wfProfileIn( __METHOD__ );
 502                 $errors = '';
 503
 504                 // Find out which modules are missing and instantiate the others
 505                 $modules = array();
 506                 $missing = array();
 507                 foreach ( $context->getModules() as $name ) {
 508                         $module = $this->getModule( $name );
 509                         if ( $module ) {
 510                                 // Do not allow private modules to be loaded from the web.
 511                                 // This is a security issue, see bug 34907.
 512                                 if ( $module->getGroup() === 'private' ) {
 513                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 514                                         $this->hasErrors = true;
 515                                         // Add exception to the output as a comment
 516                                         $errors .= self::makeComment( "Cannot show private module \"$name\"" );
 517
 518                                         continue;
 519                                 }
 520                                 $modules[$name] = $module;
 521                         } else {
 522                                 $missing[] = $name;
 523                         }
 524                 }
 525
 526                 // Preload information needed to the mtime calculation below
 527                 try {
 528                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 529                 } catch ( Exception $e ) {
 530                         MWExceptionHandler::logException( $e );
 531                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 532                         $this->hasErrors = true;
 533                         // Add exception to the output as a comment
 534                         $errors .= self::formatException( $e );
 535                 }
 536
 537                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 538
 539                 // To send Last-Modified and support If-Modified-Since, we need to detect
 540                 // the last modified time
 541                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 542                 foreach ( $modules as $module ) {
 543                         /**
 544                          * @var $module ResourceLoaderModule
 545                          */
 546                         try {
 547                                 // Calculate maximum modified time
 548                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 549                         } catch ( Exception $e ) {
 550                                 MWExceptionHandler::logException( $e );
 551                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 552                                 $this->hasErrors = true;
 553                                 // Add exception to the output as a comment
 554                                 $errors .= self::formatException( $e );
 555                         }
 556                 }
 557
 558                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 559
 560                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 561                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 562                         wfProfileOut( __METHOD__ );
 563                         return; // output handled (buffers cleared)
 564                 }
 565
 566                 // Generate a response
 567                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 568
 569                 // Prepend comments indicating exceptions
 570                 $response = $errors . $response;
 571
 572                 // Capture any PHP warnings from the output buffer and append them to the
 573                 // response in a comment if we're in debug mode.
 574                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 575                         $response = self::makeComment( $warnings ) . $response;
 576                         $this->hasErrors = true;
 577                 }
 578
 579                 // Save response to file cache unless there are errors
 580                 if ( isset( $fileCache ) && !$errors && !count( $missing ) ) {
 581                         // Cache single modules...and other requests if there are enough hits
 582                         if ( ResourceFileCache::useFileCache( $context ) ) {
 583                                 if ( $fileCache->isCacheWorthy() ) {
 584                                         $fileCache->saveText( $response );
 585                                 } else {
 586                                         $fileCache->incrMissesRecent( $context->getRequest() );
 587                                 }
 588                         }
 589                 }
 590
 591                 // Send content type and cache related headers
 592                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 593
 594                 // Remove the output buffer and output the response
 595                 ob_end_clean();
 596                 echo $response;
 597
 598                 wfProfileOut( __METHOD__ );
 599         }
 600
 601         /**
 602          * Send content type and last modified headers to the client.
 603          * @param ResourceLoaderContext $context
 604          * @param string $mtime TS_MW timestamp to use for last-modified
 605          * @param bool $errors Whether there are commented-out errors in the response
 606          * @return void
 607          */
 608         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 609                 global $wgResourceLoaderMaxage;
 610                 // If a version wasn't specified we need a shorter expiry time for updates
 611                 // to propagate to clients quickly
 612                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 613                 if ( is_null( $context->getVersion() ) || $errors ) {
 614                         $maxage = $wgResourceLoaderMaxage['unversioned']['client'];
 615                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 616                 // If a version was specified we can use a longer expiry time since changing
 617                 // version numbers causes cache misses
 618                 } else {
 619                         $maxage = $wgResourceLoaderMaxage['versioned']['client'];
 620                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 621                 }
 622                 if ( $context->getOnly() === 'styles' ) {
 623                         header( 'Content-Type: text/css; charset=utf-8' );
 624                         header( 'Access-Control-Allow-Origin: *' );
 625                 } else {
 626                         header( 'Content-Type: text/javascript; charset=utf-8' );
 627                 }
 628                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 629                 if ( $context->getDebug() ) {
 630                         // Do not cache debug responses
 631                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 632                         header( 'Pragma: no-cache' );
 633                 } else {
 634                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 635                         $exp = min( $maxage, $smaxage );
 636                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 637                 }
 638         }
 639
 640         /**
 641          * Respond with 304 Last Modified if appropiate.
 642          *
 643          * If there's an If-Modified-Since header, respond with a 304 appropriately
 644          * and clear out the output buffer. If the client cache is too old then do nothing.
 645          *
 646          * @param ResourceLoaderContext $context
 647          * @param string $mtime The TS_MW timestamp to check the header against
 648          * @return bool True if 304 header sent and output handled
 649          */
 650         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 651                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 652                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 653                 // so we get a valid timestamp.
 654                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 655                 // Never send 304s in debug mode
 656                 if ( $ims !== false && !$context->getDebug() ) {
 657                         $imsTS = strtok( $ims, ';' );
 658                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 659                                 // There's another bug in ob_gzhandler (see also the comment at
 660                                 // the top of this function) that causes it to gzip even empty
 661                                 // responses, meaning it's impossible to produce a truly empty
 662                                 // response (because the gzip header is always there). This is
 663                                 // a problem because 304 responses have to be completely empty
 664                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 665                                 // See also http://bugs.php.net/bug.php?id=51579
 666                                 // To work around this, we tear down all output buffering before
 667                                 // sending the 304.
 668                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 669
 670                                 header( 'HTTP/1.0 304 Not Modified' );
 671                                 header( 'Status: 304 Not Modified' );
 672                                 return true;
 673                         }
 674                 }
 675                 return false;
 676         }
 677
 678         /**
 679          * Send out code for a response from file cache if possible.
 680          *
 681          * @param ResourceFileCache $fileCache Cache object for this request URL
 682          * @param ResourceLoaderContext $context Context in which to generate a response
 683          * @return bool If this found a cache file and handled the response
 684          */
 685         protected function tryRespondFromFileCache(
 686                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 687         ) {
 688                 global $wgResourceLoaderMaxage;
 689                 // Buffer output to catch warnings.
 690                 ob_start();
 691                 // Get the maximum age the cache can be
 692                 $maxage = is_null( $context->getVersion() )
 693                         ? $wgResourceLoaderMaxage['unversioned']['server']
 694                         : $wgResourceLoaderMaxage['versioned']['server'];
 695                 // Minimum timestamp the cache file must have
 696                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 697                 if ( !$good ) {
 698                         try { // RL always hits the DB on file cache miss...
 699                                 wfGetDB( DB_SLAVE );
 700                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 701                                 $good = $fileCache->isCacheGood(); // cache existence check
 702                         }
 703                 }
 704                 if ( $good ) {
 705                         $ts = $fileCache->cacheTimestamp();
 706                         // Send content type and cache headers
 707                         $this->sendResponseHeaders( $context, $ts, false );
 708                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 709                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 710                                 return false; // output handled (buffers cleared)
 711                         }
 712                         $response = $fileCache->fetchText();
 713                         // Capture any PHP warnings from the output buffer and append them to the
 714                         // response in a comment if we're in debug mode.
 715                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 716                                 $response = "/*\n$warnings\n*/\n" . $response;
 717                         }
 718                         // Remove the output buffer and output the response
 719                         ob_end_clean();
 720                         echo $response . "\n/* Cached {$ts} */";
 721                         return true; // cache hit
 722                 }
 723                 // Clear buffer
 724                 ob_end_clean();
 725
 726                 return false; // cache miss
 727         }
 728
 729         /**
 730          * Generate a CSS or JS comment block.
 731          *
 732          * Only use this for public data, not error message details.
 733          *
 734          * @param string $text
 735          * @return string
 736          */
 737         public static function makeComment( $text ) {
 738                 $encText = str_replace( '*/', '* /', $text );
 739                 return "/*\n$encText\n*/\n";
 740         }
 741
 742         /**
 743          * Handle exception display.
 744          *
 745          * @param Exception $e Exception to be shown to the user
 746          * @return string Sanitized text that can be returned to the user
 747          */
 748         public static function formatException( $e ) {
 749                 global $wgShowExceptionDetails;
 750
 751                 if ( $wgShowExceptionDetails ) {
 752                         return self::makeComment( $e->__toString() );
 753                 } else {
 754                         return self::makeComment( wfMessage( 'internalerror' )->text() );
 755                 }
 756         }
 757
 758         /**
 759          * Generate code for a response.
 760          *
 761          * @param ResourceLoaderContext $context Context in which to generate a response
 762          * @param array $modules List of module objects keyed by module name
 763          * @param array $missing List of requested module names that are unregistered (optional)
 764          * @return string Response data
 765          */
 766         public function makeModuleResponse( ResourceLoaderContext $context,
 767                 array $modules, array $missing = array()
 768         ) {
 769                 $out = '';
 770                 $exceptions = '';
 771                 $states = array();
 772
 773                 if ( !count( $modules ) && !count( $missing ) ) {
 774                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 775    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 776    no modules were requested. Max made me put this here. */";
 777                 }
 778
 779                 wfProfileIn( __METHOD__ );
 780
 781                 // Pre-fetch blobs
 782                 if ( $context->shouldIncludeMessages() ) {
 783                         try {
 784                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 785                         } catch ( Exception $e ) {
 786                                 MWExceptionHandler::logException( $e );
 787                                 wfDebugLog(
 788                                         'resourceloader',
 789                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 790                                 );
 791                                 $this->hasErrors = true;
 792                                 // Add exception to the output as a comment
 793                                 $exceptions .= self::formatException( $e );
 794                         }
 795                 } else {
 796                         $blobs = array();
 797                 }
 798
 799                 foreach ( $missing as $name ) {
 800                         $states[$name] = 'missing';
 801                 }
 802
 803                 // Generate output
 804                 $isRaw = false;
 805                 foreach ( $modules as $name => $module ) {
 806                         /**
 807                          * @var $module ResourceLoaderModule
 808                          */
 809
 810                         wfProfileIn( __METHOD__ . '-' . $name );
 811                         try {
 812                                 $scripts = '';
 813                                 if ( $context->shouldIncludeScripts() ) {
 814                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 815                                         // However, we can't do this if the module doesn't support it
 816                                         // We also can't do this if there is an only= parameter, because we have to give
 817                                         // the module a way to return a load.php URL without causing an infinite loop
 818                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 819                                                 $scripts = $module->getScriptURLsForDebug( $context );
 820                                         } else {
 821                                                 $scripts = $module->getScript( $context );
 822                                                 // rtrim() because there are usually a few line breaks
 823                                                 // after the last ';'. A new line at EOF, a new line
 824                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 825                                                 if ( is_string( $scripts )
 826                                                         && strlen( $scripts )
 827                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 828                                                 ) {
 829                                                         // Append semicolon to prevent weird bugs caused by files not
 830                                                         // terminating their statements right (bug 27054)
 831                                                         $scripts .= ";\n";
 832                                                 }
 833                                         }
 834                                 }
 835                                 // Styles
 836                                 $styles = array();
 837                                 if ( $context->shouldIncludeStyles() ) {
 838                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 839                                         // that don't *have* any stylesheets (bug 38024).
 840                                         $stylePairs = $module->getStyles( $context );
 841                                         if ( count( $stylePairs ) ) {
 842                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 843                                                 // See comment near shouldIncludeScripts() for more details
 844                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 845                                                         $styles = array(
 846                                                                 'url' => $module->getStyleURLsForDebug( $context )
 847                                                         );
 848                                                 } else {
 849                                                         // Minify CSS before embedding in mw.loader.implement call
 850                                                         // (unless in debug mode)
 851                                                         if ( !$context->getDebug() ) {
 852                                                                 foreach ( $stylePairs as $media => $style ) {
 853                                                                         // Can be either a string or an array of strings.
 854                                                                         if ( is_array( $style ) ) {
 855                                                                                 $stylePairs[$media] = array();
 856                                                                                 foreach ( $style as $cssText ) {
 857                                                                                         if ( is_string( $cssText ) ) {
 858                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 859                                                                                         }
 860                                                                                 }
 861                                                                         } elseif ( is_string( $style ) ) {
 862                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 863                                                                         }
 864                                                                 }
 865                                                         }
 866                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 867                                                         $styles = array(
 868                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 869                                                         );
 870                                                 }
 871                                         }
 872                                 }
 873
 874                                 // Messages
 875                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 876
 877                                 // Append output
 878                                 switch ( $context->getOnly() ) {
 879                                         case 'scripts':
 880                                                 if ( is_string( $scripts ) ) {
 881                                                         // Load scripts raw...
 882                                                         $out .= $scripts;
 883                                                 } elseif ( is_array( $scripts ) ) {
 884                                                         // ...except when $scripts is an array of URLs
 885                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 886                                                 }
 887                                                 break;
 888                                         case 'styles':
 889                                                 // We no longer seperate into media, they are all combined now with
 890                                                 // custom media type groups into @media .. {} sections as part of the css string.
 891                                                 // Module returns either an empty array or a numerical array with css strings.
 892                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 893                                                 break;
 894                                         case 'messages':
 895                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 896                                                 break;
 897                                         default:
 898                                                 $out .= self::makeLoaderImplementScript(
 899                                                         $name,
 900                                                         $scripts,
 901                                                         $styles,
 902                                                         new XmlJsCode( $messagesBlob )
 903                                                 );
 904                                                 break;
 905                                 }
 906                         } catch ( Exception $e ) {
 907                                 MWExceptionHandler::logException( $e );
 908                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
 909                                 $this->hasErrors = true;
 910                                 // Add exception to the output as a comment
 911                                 $exceptions .= self::formatException( $e );
 912
 913                                 // Respond to client with error-state instead of module implementation
 914                                 $states[$name] = 'error';
 915                                 unset( $modules[$name] );
 916                         }
 917                         $isRaw |= $module->isRaw();
 918                         wfProfileOut( __METHOD__ . '-' . $name );
 919                 }
 920
 921                 // Update module states
 922                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
 923                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
 924                                 // Set the state of modules loaded as only scripts to ready as
 925                                 // they don't have an mw.loader.implement wrapper that sets the state
 926                                 foreach ( $modules as $name => $module ) {
 927                                         $states[$name] = 'ready';
 928                                 }
 929                         }
 930
 931                         // Set the state of modules we didn't respond to with mw.loader.implement
 932                         if ( count( $states ) ) {
 933                                 $out .= self::makeLoaderStateScript( $states );
 934                         }
 935                 } else {
 936                         if ( count( $states ) ) {
 937                                 $exceptions .= self::makeComment(
 938                                         'Problematic modules: ' . FormatJson::encode( $states, ResourceLoader::inDebugMode() )
 939                                 );
 940                         }
 941                 }
 942
 943                 if ( !$context->getDebug() ) {
 944                         if ( $context->getOnly() === 'styles' ) {
 945                                 $out = $this->filter( 'minify-css', $out );
 946                         } else {
 947                                 $out = $this->filter( 'minify-js', $out );
 948                         }
 949                 }
 950
 951                 wfProfileOut( __METHOD__ );
 952                 return $exceptions . $out;
 953         }
 954
 955         /* Static Methods */
 956
 957         /**
 958          * Return JS code that calls mw.loader.implement with given module properties.
 959          *
 960          * @param string $name Module name
 961          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
 962          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
 963          *   to CSS files keyed by media type
 964          * @param mixed $messages List of messages associated with this module. May either be an
 965          *   associative array mapping message key to value, or a JSON-encoded message blob containing
 966          *   the same data, wrapped in an XmlJsCode object.
 967          * @throws MWException
 968          * @return string
 969          */
 970         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 971                 if ( is_string( $scripts ) ) {
 972                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
 973                 } elseif ( !is_array( $scripts ) ) {
 974                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 975                 }
 976                 return Xml::encodeJsCall(
 977                         'mw.loader.implement',
 978                         array(
 979                                 $name,
 980                                 $scripts,
 981                                 // Force objects. mw.loader.implement requires them to be javascript objects.
 982                                 // Although these variables are associative arrays, which become javascript
 983                                 // objects through json_encode. In many cases they will be empty arrays, and
 984                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
 985                                 // output javascript "[]" instead of "{}". This fixes that.
 986                                 (object)$styles,
 987                                 (object)$messages
 988                         ),
 989                         ResourceLoader::inDebugMode()
 990                 );
 991         }
 992
 993         /**
 994          * Returns JS code which, when called, will register a given list of messages.
 995          *
 996          * @param mixed $messages Either an associative array mapping message key to value, or a
 997          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 998          * @return string
 999          */
1000         public static function makeMessageSetScript( $messages ) {
1001                 return Xml::encodeJsCall(
1002                         'mw.messages.set',
1003                         array( (object)$messages ),
1004                         ResourceLoader::inDebugMode()
1005                 );
1006         }
1007
1008         /**
1009          * Combines an associative array mapping media type to CSS into a
1010          * single stylesheet with "@media" blocks.
1011          *
1012          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1013          * @return array
1014          */
1015         public static function makeCombinedStyles( array $stylePairs ) {
1016                 $out = array();
1017                 foreach ( $stylePairs as $media => $styles ) {
1018                         // ResourceLoaderFileModule::getStyle can return the styles
1019                         // as a string or an array of strings. This is to allow separation in
1020                         // the front-end.
1021                         $styles = (array)$styles;
1022                         foreach ( $styles as $style ) {
1023                                 $style = trim( $style );
1024                                 // Don't output an empty "@media print { }" block (bug 40498)
1025                                 if ( $style !== '' ) {
1026                                         // Transform the media type based on request params and config
1027                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1028                                         $media = OutputPage::transformCssMedia( $media );
1029
1030                                         if ( $media === '' || $media == 'all' ) {
1031                                                 $out[] = $style;
1032                                         } elseif ( is_string( $media ) ) {
1033                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1034                                         }
1035                                         // else: skip
1036                                 }
1037                         }
1038                 }
1039                 return $out;
1040         }
1041
1042         /**
1043          * Returns a JS call to mw.loader.state, which sets the state of a
1044          * module or modules to a given value. Has two calling conventions:
1045          *
1046          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1047          *         Set the state of a single module called $name to $state
1048          *
1049          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1050          *         Set the state of modules with the given names to the given states
1051          *
1052          * @param string $name
1053          * @param string $state
1054          * @return string
1055          */
1056         public static function makeLoaderStateScript( $name, $state = null ) {
1057                 if ( is_array( $name ) ) {
1058                         return Xml::encodeJsCall(
1059                                 'mw.loader.state',
1060                                 array( $name ),
1061                                 ResourceLoader::inDebugMode()
1062                         );
1063                 } else {
1064                         return Xml::encodeJsCall(
1065                                 'mw.loader.state',
1066                                 array( $name, $state ),
1067                                 ResourceLoader::inDebugMode()
1068                         );
1069                 }
1070         }
1071
1072         /**
1073          * Returns JS code which calls the script given by $script. The script will
1074          * be called with local variables name, version, dependencies and group,
1075          * which will have values corresponding to $name, $version, $dependencies
1076          * and $group as supplied.
1077          *
1078          * @param string $name Module name
1079          * @param int $version Module version number as a timestamp
1080          * @param array $dependencies List of module names on which this module depends
1081          * @param string $group Group which the module is in.
1082          * @param string $source Source of the module, or 'local' if not foreign.
1083          * @param string $script JavaScript code
1084          * @return string
1085          */
1086         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1087                 $group, $source, $script
1088         ) {
1089                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1090                 return Xml::encodeJsCall(
1091                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1092                         array( $name, $version, $dependencies, $group, $source ),
1093                         ResourceLoader::inDebugMode()
1094                 );
1095         }
1096
1097         /**
1098          * Returns JS code which calls mw.loader.register with the given
1099          * parameters. Has three calling conventions:
1100          *
1101          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source, $skip ):
1102          *       Register a single module.
1103          *
1104          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1105          *       Register modules with the given names.
1106          *
1107          *   - ResourceLoader::makeLoaderRegisterScript( array(
1108          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1109          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1110          *        ...
1111          *     ) ):
1112          *        Registers modules with the given names and parameters.
1113          *
1114          * @param string $name Module name
1115          * @param int $version Module version number as a timestamp
1116          * @param array $dependencies List of module names on which this module depends
1117          * @param string $group Group which the module is in
1118          * @param string $source Source of the module, or 'local' if not foreign
1119          * @param string $skip Script body of the skip function
1120          * @return string
1121          */
1122         public static function makeLoaderRegisterScript( $name, $version = null,
1123                 $dependencies = null, $group = null, $source = null, $skip = null
1124         ) {
1125                 if ( is_array( $name ) ) {
1126                         return Xml::encodeJsCall(
1127                                 'mw.loader.register',
1128                                 array( $name ),
1129                                 ResourceLoader::inDebugMode()
1130                         );
1131                 } else {
1132                         $version = (int)$version > 1 ? (int)$version : 1;
1133                         return Xml::encodeJsCall(
1134                                 'mw.loader.register',
1135                                 array( $name, $version, $dependencies, $group, $source, $skip ),
1136                                 ResourceLoader::inDebugMode()
1137                         );
1138                 }
1139         }
1140
1141         /**
1142          * Returns JS code which calls mw.loader.addSource() with the given
1143          * parameters. Has two calling conventions:
1144          *
1145          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1146          *       Register a single source
1147          *
1148          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
1149          *       Register sources with the given IDs and properties.
1150          *
1151          * @param string $id Source ID
1152          * @param array $properties Source properties (see addSource())
1153          * @return string
1154          */
1155         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1156                 if ( is_array( $id ) ) {
1157                         return Xml::encodeJsCall(
1158                                 'mw.loader.addSource',
1159                                 array( $id ),
1160                                 ResourceLoader::inDebugMode()
1161                         );
1162                 } else {
1163                         return Xml::encodeJsCall(
1164                                 'mw.loader.addSource',
1165                                 array( $id, $properties ),
1166                                 ResourceLoader::inDebugMode()
1167                         );
1168                 }
1169         }
1170
1171         /**
1172          * Returns JS code which runs given JS code if the client-side framework is
1173          * present.
1174          *
1175          * @param string $script JavaScript code
1176          * @return string
1177          */
1178         public static function makeLoaderConditionalScript( $script ) {
1179                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1180         }
1181
1182         /**
1183          * Returns JS code which will set the MediaWiki configuration array to
1184          * the given value.
1185          *
1186          * @param array $configuration List of configuration values keyed by variable name
1187          * @return string
1188          */
1189         public static function makeConfigSetScript( array $configuration ) {
1190                 return Xml::encodeJsCall(
1191                         'mw.config.set',
1192                         array( $configuration ),
1193                         ResourceLoader::inDebugMode()
1194                 );
1195         }
1196
1197         /**
1198          * Convert an array of module names to a packed query string.
1199          *
1200          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1201          * becomes 'foo.bar,baz|bar.baz,quux'
1202          * @param array $modules List of module names (strings)
1203          * @return string Packed query string
1204          */
1205         public static function makePackedModulesString( $modules ) {
1206                 $groups = array(); // array( prefix => array( suffixes ) )
1207                 foreach ( $modules as $module ) {
1208                         $pos = strrpos( $module, '.' );
1209                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1210                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1211                         $groups[$prefix][] = $suffix;
1212                 }
1213
1214                 $arr = array();
1215                 foreach ( $groups as $prefix => $suffixes ) {
1216                         $p = $prefix === '' ? '' : $prefix . '.';
1217                         $arr[] = $p . implode( ',', $suffixes );
1218                 }
1219                 $str = implode( '|', $arr );
1220                 return $str;
1221         }
1222
1223         /**
1224          * Determine whether debug mode was requested
1225          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1226          * @return bool
1227          */
1228         public static function inDebugMode() {
1229                 if ( self::$debugMode === null ) {
1230                         global $wgRequest, $wgResourceLoaderDebug;
1231                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1232                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1233                         );
1234                 }
1235                 return self::$debugMode;
1236         }
1237
1238         /**
1239          * Reset static members used for caching.
1240          *
1241          * Global state and $wgRequest are evil, but we're using it right
1242          * now and sometimes we need to be able to force ResourceLoader to
1243          * re-evaluate the context because it has changed (e.g. in the test suite).
1244          */
1245         public static function clearCache() {
1246                 self::$debugMode = null;
1247         }
1248
1249         /**
1250          * Build a load.php URL
1251          *
1252          * @since 1.24
1253          * @param string $source name of the ResourceLoader source
1254          * @param ResourceLoaderContext $context
1255          * @param array $extraQuery
1256          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1257          */
1258         public function createLoaderURL( $source, ResourceLoaderContext $context,
1259                 $extraQuery = array()
1260         ) {
1261                 $query = self::createLoaderQuery( $context, $extraQuery );
1262                 $script = $this->getLoadScript( $source );
1263
1264                 // Prevent the IE6 extension check from being triggered (bug 28840)
1265                 // by appending a character that's invalid in Windows extensions ('*')
1266                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1267         }
1268
1269         /**
1270          * Build a load.php URL
1271          * @deprecated since 1.24, use createLoaderURL instead
1272          * @param array $modules Array of module names (strings)
1273          * @param string $lang Language code
1274          * @param string $skin Skin name
1275          * @param string|null $user User name. If null, the &user= parameter is omitted
1276          * @param string|null $version Versioning timestamp
1277          * @param bool $debug Whether the request should be in debug mode
1278          * @param string|null $only &only= parameter
1279          * @param bool $printable Printable mode
1280          * @param bool $handheld Handheld mode
1281          * @param array $extraQuery Extra query parameters to add
1282          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1283          */
1284         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1285                 $version = null, $debug = false, $only = null, $printable = false,
1286                 $handheld = false, $extraQuery = array()
1287         ) {
1288                 global $wgLoadScript;
1289
1290                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1291                         $only, $printable, $handheld, $extraQuery
1292                 );
1293
1294                 // Prevent the IE6 extension check from being triggered (bug 28840)
1295                 // by appending a character that's invalid in Windows extensions ('*')
1296                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1297         }
1298
1299         /**
1300          * Helper for createLoaderURL()
1301          *
1302          * @since 1.24
1303          * @see makeLoaderQuery
1304          * @param ResourceLoaderContext $context
1305          * @param array $extraQuery
1306          * @return array
1307          */
1308         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1309                 return self::makeLoaderQuery(
1310                         $context->getModules(),
1311                         $context->getLanguage(),
1312                         $context->getSkin(),
1313                         $context->getUser(),
1314                         $context->getVersion(),
1315                         $context->getDebug(),
1316                         $context->getOnly(),
1317                         $context->getRequest()->getBool( 'printable' ),
1318                         $context->getRequest()->getBool( 'handheld' ),
1319                         $extraQuery
1320                 );
1321         }
1322
1323         /**
1324          * Build a query array (array representation of query string) for load.php. Helper
1325          * function for makeLoaderURL().
1326          *
1327          * @param array $modules
1328          * @param string $lang
1329          * @param string $skin
1330          * @param string $user
1331          * @param string $version
1332          * @param bool $debug
1333          * @param string $only
1334          * @param bool $printable
1335          * @param bool $handheld
1336          * @param array $extraQuery
1337          *
1338          * @return array
1339          */
1340         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1341                 $version = null, $debug = false, $only = null, $printable = false,
1342                 $handheld = false, $extraQuery = array()
1343         ) {
1344                 $query = array(
1345                         'modules' => self::makePackedModulesString( $modules ),
1346                         'lang' => $lang,
1347                         'skin' => $skin,
1348                         'debug' => $debug ? 'true' : 'false',
1349                 );
1350                 if ( $user !== null ) {
1351                         $query['user'] = $user;
1352                 }
1353                 if ( $version !== null ) {
1354                         $query['version'] = $version;
1355                 }
1356                 if ( $only !== null ) {
1357                         $query['only'] = $only;
1358                 }
1359                 if ( $printable ) {
1360                         $query['printable'] = 1;
1361                 }
1362                 if ( $handheld ) {
1363                         $query['handheld'] = 1;
1364                 }
1365                 $query += $extraQuery;
1366
1367                 // Make queries uniform in order
1368                 ksort( $query );
1369                 return $query;
1370         }
1371
1372         /**
1373          * Check a module name for validity.
1374          *
1375          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1376          * at most 255 bytes.
1377          *
1378          * @param string $moduleName Module name to check
1379          * @return bool Whether $moduleName is a valid module name
1380          */
1381         public static function isValidModuleName( $moduleName ) {
1382                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1383         }
1384
1385         /**
1386          * Returns LESS compiler set up for use with MediaWiki
1387          *
1388          * @since 1.22
1389          * @return lessc
1390          */
1391         public static function getLessCompiler() {
1392                 global $wgResourceLoaderLESSFunctions, $wgResourceLoaderLESSImportPaths;
1393
1394                 // When called from the installer, it is possible that a required PHP extension
1395                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1396                 // exception (caught by the installer) to prevent a fatal error later on.
1397                 if ( !function_exists( 'ctype_digit' ) ) {
1398                         throw new MWException( 'lessc requires the Ctype extension' );
1399                 }
1400
1401                 $less = new lessc();
1402                 $less->setPreserveComments( true );
1403                 $less->setVariables( self::getLESSVars() );
1404                 $less->setImportDir( $wgResourceLoaderLESSImportPaths );
1405                 foreach ( $wgResourceLoaderLESSFunctions as $name => $func ) {
1406                         $less->registerFunction( $name, $func );
1407                 }
1408                 return $less;
1409         }
1410
1411         /**
1412          * Get global LESS variables.
1413          *
1414          * $since 1.22
1415          * @return array Map of variable names to string CSS values.
1416          */
1417         public static function getLESSVars() {
1418                 global $wgResourceLoaderLESSVars;
1419
1420                 $lessVars = $wgResourceLoaderLESSVars;
1421                 // Sort by key to ensure consistent hashing for cache lookups.
1422                 ksort( $lessVars );
1423                 return $lessVars;
1424         }
1425 }