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 use Psr\Log\LoggerAwareInterface;
  26 use Psr\Log\LoggerInterface;
  27 use Psr\Log\NullLogger;
  28
  29 /**
  30  * Dynamic JavaScript and CSS resource loading system.
  31  *
  32  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  33  *    https://www.mediawiki.org/wiki/ResourceLoader
  34  */
  35 class ResourceLoader implements LoggerAwareInterface {
  36         /** @var int */
  37         protected static $filterCacheVersion = 7;
  38
  39         /** @var bool */
  40         protected static $debugMode = null;
  41
  42         /** @var array */
  43         private static $lessVars = null;
  44
  45         /**
  46          * Module name/ResourceLoaderModule object pairs
  47          * @var array
  48          */
  49         protected $modules = array();
  50
  51         /**
  52          * Associative array mapping module name to info associative array
  53          * @var array
  54          */
  55         protected $moduleInfos = array();
  56
  57         /** @var Config $config */
  58         private $config;
  59
  60         /**
  61          * Associative array mapping framework ids to a list of names of test suite modules
  62          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  63          * @var array
  64          */
  65         protected $testModuleNames = array();
  66
  67         /**
  68          * E.g. array( 'source-id' => 'http://.../load.php' )
  69          * @var array
  70          */
  71         protected $sources = array();
  72
  73         /**
  74          * Errors accumulated during current respond() call.
  75          * @var array
  76          */
  77         protected $errors = array();
  78
  79         /**
  80          * @var MessageBlobStore
  81          */
  82         protected $blobStore;
  83
  84         /**
  85          * @var LoggerInterface
  86          */
  87         private $logger;
  88
  89         /**
  90          * Load information stored in the database about modules.
  91          *
  92          * This method grabs modules dependencies from the database and updates modules
  93          * objects.
  94          *
  95          * This is not inside the module code because it is much faster to
  96          * request all of the information at once than it is to have each module
  97          * requests its own information. This sacrifice of modularity yields a substantial
  98          * performance improvement.
  99          *
 100          * @param array $modules List of module names to preload information for
 101          * @param ResourceLoaderContext $context Context to load the information within
 102          */
 103         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
 104                 if ( !count( $modules ) ) {
 105                         // Or else Database*::select() will explode, plus it's cheaper!
 106                         return;
 107                 }
 108                 $dbr = wfGetDB( DB_SLAVE );
 109                 $skin = $context->getSkin();
 110                 $lang = $context->getLanguage();
 111
 112                 // Get file dependency information
 113                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
 114                                 'md_module' => $modules,
 115                                 'md_skin' => $skin
 116                         ), __METHOD__
 117                 );
 118
 119                 // Set modules' dependencies
 120                 $modulesWithDeps = array();
 121                 foreach ( $res as $row ) {
 122                         $module = $this->getModule( $row->md_module );
 123                         if ( $module ) {
 124                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 125                                 $modulesWithDeps[] = $row->md_module;
 126                         }
 127                 }
 128
 129                 // Register the absence of a dependency row too
 130                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 131                         $module = $this->getModule( $name );
 132                         if ( $module ) {
 133                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 134                         }
 135                 }
 136
 137                 // Get message blob mtimes. Only do this for modules with messages
 138                 $modulesWithMessages = array();
 139                 foreach ( $modules as $name ) {
 140                         $module = $this->getModule( $name );
 141                         if ( $module && count( $module->getMessages() ) ) {
 142                                 $modulesWithMessages[] = $name;
 143                         }
 144                 }
 145                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 146                 if ( count( $modulesWithMessages ) ) {
 147                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 148                                         'mr_resource' => $modulesWithMessages,
 149                                         'mr_lang' => $lang
 150                                 ), __METHOD__
 151                         );
 152                         foreach ( $res as $row ) {
 153                                 $module = $this->getModule( $row->mr_resource );
 154                                 if ( $module ) {
 155                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 156                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 157                                 }
 158                         }
 159                 }
 160                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 161                         $module = $this->getModule( $name );
 162                         if ( $module ) {
 163                                 $module->setMsgBlobMtime( $lang, 1 );
 164                         }
 165                 }
 166         }
 167
 168         /**
 169          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 170          *
 171          * Available filters are:
 172          *
 173          *    - minify-js \see JavaScriptMinifier::minify
 174          *    - minify-css \see CSSMin::minify
 175          *
 176          * If $data is empty, only contains whitespace or the filter was unknown,
 177          * $data is returned unmodified.
 178          *
 179          * @param string $filter Name of filter to run
 180          * @param string $data Text to filter, such as JavaScript or CSS text
 181          * @param array $options For back-compat, can also be the boolean value for "cacheReport". Keys:
 182          *  - (bool) cache: Whether to allow caching this data. Default: true.
 183          *  - (bool) cacheReport: Whether to include the "cache key" report comment. Default: true.
 184          * @return string Filtered data, or a comment containing an error message
 185          */
 186         public function filter( $filter, $data, $options = array() ) {
 187                 // Back-compat
 188                 if ( is_bool( $options ) ) {
 189                         $options = array( 'cacheReport' => $options );
 190                 }
 191                 // Defaults
 192                 $options += array( 'cache' => true, 'cacheReport' => true );
 193
 194                 // Don't filter empty content
 195                 if ( trim( $data ) === '' ) {
 196                         return $data;
 197                 }
 198
 199                 if ( !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 200                         $this->logger->warning( 'Invalid filter {filter}', array(
 201                                 'filter' => $filter
 202                         ) );
 203                         return $data;
 204                 }
 205
 206                 if ( !$options['cache'] ) {
 207                         $result = $this->applyFilter( $filter, $data );
 208                 } else {
 209                         $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 210                         $cache = wfGetCache( wfIsHHVM() ? CACHE_ACCEL : CACHE_ANYTHING );
 211                         $cacheEntry = $cache->get( $key );
 212                         if ( is_string( $cacheEntry ) ) {
 213                                 wfIncrStats( "resourceloader_cache.$filter.hit" );
 214                                 return $cacheEntry;
 215                         }
 216                         $result = '';
 217                         try {
 218                                 wfIncrStats( "resourceloader_cache.$filter.miss" );
 219                                 $result = $this->applyFilter( $filter, $data );
 220                                 if ( $options['cacheReport'] ) {
 221                                         $result .= "\n/* cache key: $key */";
 222                                 }
 223                                 $cache->set( $key, $result );
 224                         } catch ( Exception $e ) {
 225                                 MWExceptionHandler::logException( $e );
 226                                 $this->logger->warning( 'Minification failed: {exception}', array(
 227                                         'exception' => $e
 228                                 ) );
 229                                 $this->errors[] = self::formatExceptionNoComment( $e );
 230                         }
 231                 }
 232
 233                 return $result;
 234         }
 235
 236         private function applyFilter( $filter, $data ) {
 237                         switch ( $filter ) {
 238                                 case 'minify-js':
 239                                         return JavaScriptMinifier::minify( $data,
 240                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 241                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 242                                         );
 243                                 case 'minify-css':
 244                                         return CSSMin::minify( $data );
 245                         }
 246                         return $data;
 247         }
 248
 249         /* Methods */
 250
 251         /**
 252          * Register core modules and runs registration hooks.
 253          * @param Config|null $config
 254          */
 255         public function __construct( Config $config = null, LoggerInterface $logger = null ) {
 256                 global $IP;
 257
 258                 if ( !$logger ) {
 259                         $logger = new NullLogger();
 260                 }
 261                 $this->setLogger( $logger );
 262
 263                 if ( !$config ) {
 264                         $this->logger->debug( __METHOD__ . ' was called without providing a Config instance' );
 265                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 266                 }
 267                 $this->config = $config;
 268
 269                 // Add 'local' source first
 270                 $this->addSource( 'local', wfScript( 'load' ) );
 271
 272                 // Add other sources
 273                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 274
 275                 // Register core modules
 276                 $this->register( include "$IP/resources/Resources.php" );
 277                 $this->register( include "$IP/resources/ResourcesOOUI.php" );
 278                 // Register extension modules
 279                 Hooks::run( 'ResourceLoaderRegisterModules', array( &$this ) );
 280                 $this->register( $config->get( 'ResourceModules' ) );
 281
 282                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 283                         $this->registerTestModules();
 284                 }
 285
 286                 $this->setMessageBlobStore( new MessageBlobStore() );
 287         }
 288
 289         /**
 290          * @return Config
 291          */
 292         public function getConfig() {
 293                 return $this->config;
 294         }
 295
 296         public function setLogger( LoggerInterface $logger ) {
 297                 $this->logger = $logger;
 298         }
 299
 300         /**
 301          * @param MessageBlobStore $blobStore
 302          * @since 1.25
 303          */
 304         public function setMessageBlobStore( MessageBlobStore $blobStore ) {
 305                 $this->blobStore = $blobStore;
 306         }
 307
 308         /**
 309          * Register a module with the ResourceLoader system.
 310          *
 311          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 312          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 313          *   this may also be a ResourceLoaderModule object. Optional when using
 314          *   multiple-registration calling style.
 315          * @throws MWException If a duplicate module registration is attempted
 316          * @throws MWException If a module name contains illegal characters (pipes or commas)
 317          * @throws MWException If something other than a ResourceLoaderModule is being registered
 318          * @return bool False if there were any errors, in which case one or more modules were
 319          *   not registered
 320          */
 321         public function register( $name, $info = null ) {
 322
 323                 // Allow multiple modules to be registered in one call
 324                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 325                 foreach ( $registrations as $name => $info ) {
 326                         // Disallow duplicate registrations
 327                         if ( isset( $this->moduleInfos[$name] ) ) {
 328                                 // A module has already been registered by this name
 329                                 throw new MWException(
 330                                         'ResourceLoader duplicate registration error. ' .
 331                                         'Another module has already been registered as ' . $name
 332                                 );
 333                         }
 334
 335                         // Check $name for validity
 336                         if ( !self::isValidModuleName( $name ) ) {
 337                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 338                                         . "see ResourceLoader::isValidModuleName()" );
 339                         }
 340
 341                         // Attach module
 342                         if ( $info instanceof ResourceLoaderModule ) {
 343                                 $this->moduleInfos[$name] = array( 'object' => $info );
 344                                 $info->setName( $name );
 345                                 $this->modules[$name] = $info;
 346                         } elseif ( is_array( $info ) ) {
 347                                 // New calling convention
 348                                 $this->moduleInfos[$name] = $info;
 349                         } else {
 350                                 throw new MWException(
 351                                         'ResourceLoader module info type error for module \'' . $name .
 352                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 353                                 );
 354                         }
 355
 356                         // Last-minute changes
 357
 358                         // Apply custom skin-defined styles to existing modules.
 359                         if ( $this->isFileModule( $name ) ) {
 360                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 361                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 362                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 363                                                 continue;
 364                                         }
 365
 366                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 367                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 368                                         if ( isset( $skinStyles[$name] ) ) {
 369                                                 $paths = (array)$skinStyles[$name];
 370                                                 $styleFiles = array();
 371                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 372                                                 $paths = (array)$skinStyles['+' . $name];
 373                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 374                                                         (array)$this->moduleInfos[$name]['skinStyles']['default'] :
 375                                                         array();
 376                                         } else {
 377                                                 continue;
 378                                         }
 379
 380                                         // Add new file paths, remapping them to refer to our directories and not use settings
 381                                         // from the module we're modifying, which come from the base definition.
 382                                         list( $localBasePath, $remoteBasePath ) =
 383                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 384
 385                                         foreach ( $paths as $path ) {
 386                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 387                                         }
 388
 389                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 390                                 }
 391                         }
 392                 }
 393
 394         }
 395
 396         /**
 397          */
 398         public function registerTestModules() {
 399                 global $IP;
 400
 401                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 402                         throw new MWException( 'Attempt to register JavaScript test modules '
 403                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 404                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 405                 }
 406
 407                 // Get core test suites
 408                 $testModules = array();
 409                 $testModules['qunit'] = array();
 410                 // Get other test suites (e.g. from extensions)
 411                 Hooks::run( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 412
 413                 // Add the testrunner (which configures QUnit) to the dependencies.
 414                 // Since it must be ready before any of the test suites are executed.
 415                 foreach ( $testModules['qunit'] as &$module ) {
 416                         // Make sure all test modules are top-loading so that when QUnit starts
 417                         // on document-ready, it will run once and finish. If some tests arrive
 418                         // later (possibly after QUnit has already finished) they will be ignored.
 419                         $module['position'] = 'top';
 420                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 421                 }
 422
 423                 $testModules['qunit'] =
 424                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 425
 426                 foreach ( $testModules as $id => $names ) {
 427                         // Register test modules
 428                         $this->register( $testModules[$id] );
 429
 430                         // Keep track of their names so that they can be loaded together
 431                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 432                 }
 433
 434         }
 435
 436         /**
 437          * Add a foreign source of modules.
 438          *
 439          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 440          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 441          *  backwards-compatibility.
 442          * @throws MWException
 443          */
 444         public function addSource( $id, $loadUrl = null ) {
 445                 // Allow multiple sources to be registered in one call
 446                 if ( is_array( $id ) ) {
 447                         foreach ( $id as $key => $value ) {
 448                                 $this->addSource( $key, $value );
 449                         }
 450                         return;
 451                 }
 452
 453                 // Disallow duplicates
 454                 if ( isset( $this->sources[$id] ) ) {
 455                         throw new MWException(
 456                                 'ResourceLoader duplicate source addition error. ' .
 457                                 'Another source has already been registered as ' . $id
 458                         );
 459                 }
 460
 461                 // Pre 1.24 backwards-compatibility
 462                 if ( is_array( $loadUrl ) ) {
 463                         if ( !isset( $loadUrl['loadScript'] ) ) {
 464                                 throw new MWException(
 465                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 466                                 );
 467                         }
 468
 469                         $loadUrl = $loadUrl['loadScript'];
 470                 }
 471
 472                 $this->sources[$id] = $loadUrl;
 473         }
 474
 475         /**
 476          * Get a list of module names.
 477          *
 478          * @return array List of module names
 479          */
 480         public function getModuleNames() {
 481                 return array_keys( $this->moduleInfos );
 482         }
 483
 484         /**
 485          * Get a list of test module names for one (or all) frameworks.
 486          *
 487          * If the given framework id is unknkown, or if the in-object variable is not an array,
 488          * then it will return an empty array.
 489          *
 490          * @param string $framework Get only the test module names for one
 491          *   particular framework (optional)
 492          * @return array
 493          */
 494         public function getTestModuleNames( $framework = 'all' ) {
 495                 /** @todo api siteinfo prop testmodulenames modulenames */
 496                 if ( $framework == 'all' ) {
 497                         return $this->testModuleNames;
 498                 } elseif ( isset( $this->testModuleNames[$framework] )
 499                         && is_array( $this->testModuleNames[$framework] )
 500                 ) {
 501                         return $this->testModuleNames[$framework];
 502                 } else {
 503                         return array();
 504                 }
 505         }
 506
 507         /**
 508          * Check whether a ResourceLoader module is registered
 509          *
 510          * @since 1.25
 511          * @param string $name
 512          * @return bool
 513          */
 514         public function isModuleRegistered( $name ) {
 515                 return isset( $this->moduleInfos[$name] );
 516         }
 517
 518         /**
 519          * Get the ResourceLoaderModule object for a given module name.
 520          *
 521          * If an array of module parameters exists but a ResourceLoaderModule object has not
 522          * yet been instantiated, this method will instantiate and cache that object such that
 523          * subsequent calls simply return the same object.
 524          *
 525          * @param string $name Module name
 526          * @return ResourceLoaderModule|null If module has been registered, return a
 527          *  ResourceLoaderModule instance. Otherwise, return null.
 528          */
 529         public function getModule( $name ) {
 530                 if ( !isset( $this->modules[$name] ) ) {
 531                         if ( !isset( $this->moduleInfos[$name] ) ) {
 532                                 // No such module
 533                                 return null;
 534                         }
 535                         // Construct the requested object
 536                         $info = $this->moduleInfos[$name];
 537                         /** @var ResourceLoaderModule $object */
 538                         if ( isset( $info['object'] ) ) {
 539                                 // Object given in info array
 540                                 $object = $info['object'];
 541                         } else {
 542                                 if ( !isset( $info['class'] ) ) {
 543                                         $class = 'ResourceLoaderFileModule';
 544                                 } else {
 545                                         $class = $info['class'];
 546                                 }
 547                                 /** @var ResourceLoaderModule $object */
 548                                 $object = new $class( $info );
 549                                 $object->setConfig( $this->getConfig() );
 550                         }
 551                         $object->setName( $name );
 552                         $this->modules[$name] = $object;
 553                 }
 554
 555                 return $this->modules[$name];
 556         }
 557
 558         /**
 559          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 560          *
 561          * @param string $name Module name
 562          * @return bool
 563          */
 564         protected function isFileModule( $name ) {
 565                 if ( !isset( $this->moduleInfos[$name] ) ) {
 566                         return false;
 567                 }
 568                 $info = $this->moduleInfos[$name];
 569                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 570                         return false;
 571                 }
 572                 return true;
 573         }
 574
 575         /**
 576          * Get the list of sources.
 577          *
 578          * @return array Like array( id => load.php url, .. )
 579          */
 580         public function getSources() {
 581                 return $this->sources;
 582         }
 583
 584         /**
 585          * Get the URL to the load.php endpoint for the given
 586          * ResourceLoader source
 587          *
 588          * @since 1.24
 589          * @param string $source
 590          * @throws MWException On an invalid $source name
 591          * @return string
 592          */
 593         public function getLoadScript( $source ) {
 594                 if ( !isset( $this->sources[$source] ) ) {
 595                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 596                 }
 597                 return $this->sources[$source];
 598         }
 599
 600         /**
 601          * @since 1.26
 602          * @param string $value
 603          * @return string Hash
 604          */
 605         public static function makeHash( $value ) {
 606                 // Use base64 to output more entropy in a more compact string (default hex is only base16).
 607                 // The first 8 chars of a base64 encoded digest represent the same binary as
 608                 // the first 12 chars of a hex encoded digest.
 609                 return substr( base64_encode( sha1( $value, true ) ), 0, 8 );
 610         }
 611
 612         /**
 613          * Helper method to get and combine versions of multiple modules.
 614          *
 615          * @since 1.26
 616          * @param ResourceLoaderContext $context
 617          * @param array $modules List of ResourceLoaderModule objects
 618          * @return string Hash
 619          */
 620         public function getCombinedVersion( ResourceLoaderContext $context, Array $modules ) {
 621                 if ( !$modules ) {
 622                         return '';
 623                 }
 624                 // Support: PHP 5.3 ("$this" for anonymous functions was added in PHP 5.4.0)
 625                 // http://php.net/functions.anonymous
 626                 $rl = $this;
 627                 $hashes = array_map( function ( $module ) use ( $rl, $context ) {
 628                         return $rl->getModule( $module )->getVersionHash( $context );
 629                 }, $modules );
 630                 return self::makeHash( implode( $hashes ) );
 631         }
 632
 633         /**
 634          * Output a response to a load request, including the content-type header.
 635          *
 636          * @param ResourceLoaderContext $context Context in which a response should be formed
 637          */
 638         public function respond( ResourceLoaderContext $context ) {
 639                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 640                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 641                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 642                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 643                 // the whole thing in our own output buffer to be sure the active buffer
 644                 // doesn't use ob_gzhandler.
 645                 // See http://bugs.php.net/bug.php?id=36514
 646                 ob_start();
 647
 648                 // Find out which modules are missing and instantiate the others
 649                 $modules = array();
 650                 $missing = array();
 651                 foreach ( $context->getModules() as $name ) {
 652                         $module = $this->getModule( $name );
 653                         if ( $module ) {
 654                                 // Do not allow private modules to be loaded from the web.
 655                                 // This is a security issue, see bug 34907.
 656                                 if ( $module->getGroup() === 'private' ) {
 657                                         $this->logger->debug( "Request for private module '$name' denied" );
 658                                         $this->errors[] = "Cannot show private module \"$name\"";
 659                                         continue;
 660                                 }
 661                                 $modules[$name] = $module;
 662                         } else {
 663                                 $missing[] = $name;
 664                         }
 665                 }
 666
 667                 try {
 668                         // Preload for getCombinedVersion()
 669                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 670                 } catch ( Exception $e ) {
 671                         MWExceptionHandler::logException( $e );
 672                         $this->logger->warning( 'Preloading module info failed: {exception}', array(
 673                                 'exception' => $e
 674                         ) );
 675                         $this->errors[] = self::formatExceptionNoComment( $e );
 676                 }
 677
 678                 // Combine versions to propagate cache invalidation
 679                 $versionHash = '';
 680                 try {
 681                         $versionHash = $this->getCombinedVersion( $context, array_keys( $modules ) );
 682                 } catch ( Exception $e ) {
 683                         MWExceptionHandler::logException( $e );
 684                         $this->logger->warning( 'Calculating version hash failed: {exception}', array(
 685                                 'exception' => $e
 686                         ) );
 687                         $this->errors[] = self::formatExceptionNoComment( $e );
 688                 }
 689
 690                 // See RFC 2616 § 3.11 Entity Tags
 691                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.11
 692                 $etag = 'W/"' . $versionHash . '"';
 693
 694                 // Try the client-side cache first
 695                 if ( $this->tryRespondNotModified( $context, $etag ) ) {
 696                         return; // output handled (buffers cleared)
 697                 }
 698
 699                 // Use file cache if enabled and available...
 700                 if ( $this->config->get( 'UseFileCache' ) ) {
 701                         $fileCache = ResourceFileCache::newFromContext( $context );
 702                         if ( $this->tryRespondFromFileCache( $fileCache, $context, $etag ) ) {
 703                                 return; // output handled
 704                         }
 705                 }
 706
 707                 // Generate a response
 708                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 709
 710                 // Capture any PHP warnings from the output buffer and append them to the
 711                 // error list if we're in debug mode.
 712                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 713                         $this->errors[] = $warnings;
 714                 }
 715
 716                 // Save response to file cache unless there are errors
 717                 if ( isset( $fileCache ) && !$this->errors && !count( $missing ) ) {
 718                         // Cache single modules and images...and other requests if there are enough hits
 719                         if ( ResourceFileCache::useFileCache( $context ) ) {
 720                                 if ( $fileCache->isCacheWorthy() ) {
 721                                         $fileCache->saveText( $response );
 722                                 } else {
 723                                         $fileCache->incrMissesRecent( $context->getRequest() );
 724                                 }
 725                         }
 726                 }
 727
 728                 $this->sendResponseHeaders( $context, $etag, (bool)$this->errors );
 729
 730                 // Remove the output buffer and output the response
 731                 ob_end_clean();
 732
 733                 if ( $context->getImageObj() && $this->errors ) {
 734                         // We can't show both the error messages and the response when it's an image.
 735                         $errorText = '';
 736                         foreach ( $this->errors as $error ) {
 737                                 $errorText .= $error . "\n";
 738                         }
 739                         $response = $errorText;
 740                 } elseif ( $this->errors ) {
 741                         // Prepend comments indicating errors
 742                         $errorText = '';
 743                         foreach ( $this->errors as $error ) {
 744                                 $errorText .= self::makeComment( $error );
 745                         }
 746                         $response = $errorText . $response;
 747                 }
 748
 749                 $this->errors = array();
 750                 echo $response;
 751
 752         }
 753
 754         /**
 755          * Send main response headers to the client.
 756          *
 757          * Deals with Content-Type, CORS (for stylesheets), and caching.
 758          *
 759          * @param ResourceLoaderContext $context
 760          * @param string $etag ETag header value
 761          * @param bool $errors Whether there are errors in the response
 762          * @return void
 763          */
 764         protected function sendResponseHeaders( ResourceLoaderContext $context, $etag, $errors ) {
 765                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 766                 // If a version wasn't specified we need a shorter expiry time for updates
 767                 // to propagate to clients quickly
 768                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 769                 if ( is_null( $context->getVersion() ) || $errors ) {
 770                         $maxage = $rlMaxage['unversioned']['client'];
 771                         $smaxage = $rlMaxage['unversioned']['server'];
 772                 // If a version was specified we can use a longer expiry time since changing
 773                 // version numbers causes cache misses
 774                 } else {
 775                         $maxage = $rlMaxage['versioned']['client'];
 776                         $smaxage = $rlMaxage['versioned']['server'];
 777                 }
 778                 if ( $context->getImageObj() ) {
 779                         // Output different headers if we're outputting textual errors.
 780                         if ( $errors ) {
 781                                 header( 'Content-Type: text/plain; charset=utf-8' );
 782                         } else {
 783                                 $context->getImageObj()->sendResponseHeaders( $context );
 784                         }
 785                 } elseif ( $context->getOnly() === 'styles' ) {
 786                         header( 'Content-Type: text/css; charset=utf-8' );
 787                         header( 'Access-Control-Allow-Origin: *' );
 788                 } else {
 789                         header( 'Content-Type: text/javascript; charset=utf-8' );
 790                 }
 791                 // See RFC 2616 § 14.19 ETag
 792                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19
 793                 header( 'ETag: ' . $etag );
 794                 if ( $context->getDebug() ) {
 795                         // Do not cache debug responses
 796                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 797                         header( 'Pragma: no-cache' );
 798                 } else {
 799                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 800                         $exp = min( $maxage, $smaxage );
 801                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 802                 }
 803         }
 804
 805         /**
 806          * Respond with HTTP 304 Not Modified if appropiate.
 807          *
 808          * If there's an If-None-Match header, respond with a 304 appropriately
 809          * and clear out the output buffer. If the client cache is too old then do nothing.
 810          *
 811          * @param ResourceLoaderContext $context
 812          * @param string $etag ETag header value
 813          * @return bool True if HTTP 304 was sent and output handled
 814          */
 815         protected function tryRespondNotModified( ResourceLoaderContext $context, $etag ) {
 816                 // See RFC 2616 § 14.26 If-None-Match
 817                 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
 818                 $clientKeys = $context->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST );
 819                 // Never send 304s in debug mode
 820                 if ( $clientKeys !== false && !$context->getDebug() && in_array( $etag, $clientKeys ) ) {
 821                         // There's another bug in ob_gzhandler (see also the comment at
 822                         // the top of this function) that causes it to gzip even empty
 823                         // responses, meaning it's impossible to produce a truly empty
 824                         // response (because the gzip header is always there). This is
 825                         // a problem because 304 responses have to be completely empty
 826                         // per the HTTP spec, and Firefox behaves buggily when they're not.
 827                         // See also http://bugs.php.net/bug.php?id=51579
 828                         // To work around this, we tear down all output buffering before
 829                         // sending the 304.
 830                         wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 831
 832                         HttpStatus::header( 304 );
 833
 834                         $this->sendResponseHeaders( $context, $etag, false );
 835                         return true;
 836                 }
 837                 return false;
 838         }
 839
 840         /**
 841          * Send out code for a response from file cache if possible.
 842          *
 843          * @param ResourceFileCache $fileCache Cache object for this request URL
 844          * @param ResourceLoaderContext $context Context in which to generate a response
 845          * @param string $etag ETag header value
 846          * @return bool If this found a cache file and handled the response
 847          */
 848         protected function tryRespondFromFileCache(
 849                 ResourceFileCache $fileCache,
 850                 ResourceLoaderContext $context,
 851                 $etag
 852         ) {
 853                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 854                 // Buffer output to catch warnings.
 855                 ob_start();
 856                 // Get the maximum age the cache can be
 857                 $maxage = is_null( $context->getVersion() )
 858                         ? $rlMaxage['unversioned']['server']
 859                         : $rlMaxage['versioned']['server'];
 860                 // Minimum timestamp the cache file must have
 861                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 862                 if ( !$good ) {
 863                         try { // RL always hits the DB on file cache miss...
 864                                 wfGetDB( DB_SLAVE );
 865                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 866                                 $good = $fileCache->isCacheGood(); // cache existence check
 867                         }
 868                 }
 869                 if ( $good ) {
 870                         $ts = $fileCache->cacheTimestamp();
 871                         // Send content type and cache headers
 872                         $this->sendResponseHeaders( $context, $etag, false );
 873                         $response = $fileCache->fetchText();
 874                         // Capture any PHP warnings from the output buffer and append them to the
 875                         // response in a comment if we're in debug mode.
 876                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 877                                 $response = self::makeComment( $warnings ) . $response;
 878                         }
 879                         // Remove the output buffer and output the response
 880                         ob_end_clean();
 881                         echo $response . "\n/* Cached {$ts} */";
 882                         return true; // cache hit
 883                 }
 884                 // Clear buffer
 885                 ob_end_clean();
 886
 887                 return false; // cache miss
 888         }
 889
 890         /**
 891          * Generate a CSS or JS comment block.
 892          *
 893          * Only use this for public data, not error message details.
 894          *
 895          * @param string $text
 896          * @return string
 897          */
 898         public static function makeComment( $text ) {
 899                 $encText = str_replace( '*/', '* /', $text );
 900                 return "/*\n$encText\n*/\n";
 901         }
 902
 903         /**
 904          * Handle exception display.
 905          *
 906          * @param Exception $e Exception to be shown to the user
 907          * @return string Sanitized text in a CSS/JS comment that can be returned to the user
 908          */
 909         public static function formatException( $e ) {
 910                 return self::makeComment( self::formatExceptionNoComment( $e ) );
 911         }
 912
 913         /**
 914          * Handle exception display.
 915          *
 916          * @since 1.25
 917          * @param Exception $e Exception to be shown to the user
 918          * @return string Sanitized text that can be returned to the user
 919          */
 920         protected static function formatExceptionNoComment( $e ) {
 921                 global $wgShowExceptionDetails;
 922
 923                 if ( $wgShowExceptionDetails ) {
 924                         return $e->__toString();
 925                 } else {
 926                         return wfMessage( 'internalerror' )->text();
 927                 }
 928         }
 929
 930         /**
 931          * Generate code for a response.
 932          *
 933          * @param ResourceLoaderContext $context Context in which to generate a response
 934          * @param array $modules List of module objects keyed by module name
 935          * @param array $missing List of requested module names that are unregistered (optional)
 936          * @return string Response data
 937          */
 938         public function makeModuleResponse( ResourceLoaderContext $context,
 939                 array $modules, array $missing = array()
 940         ) {
 941                 $out = '';
 942                 $states = array();
 943
 944                 if ( !count( $modules ) && !count( $missing ) ) {
 945                         return <<<MESSAGE
 946 /* This file is the Web entry point for MediaWiki's ResourceLoader:
 947    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 948    no modules were requested. Max made me put this here. */
 949 MESSAGE;
 950                 }
 951
 952                 $image = $context->getImageObj();
 953                 if ( $image ) {
 954                         $data = $image->getImageData( $context );
 955                         if ( $data === false ) {
 956                                 $data = '';
 957                                 $this->errors[] = 'Image generation failed';
 958                         }
 959                         return $data;
 960                 }
 961
 962                 // Pre-fetch blobs
 963                 if ( $context->shouldIncludeMessages() ) {
 964                         try {
 965                                 $blobs = $this->blobStore->get( $this, $modules, $context->getLanguage() );
 966                         } catch ( Exception $e ) {
 967                                 MWExceptionHandler::logException( $e );
 968                                 $this->logger->warning( 'Prefetching MessageBlobStore failed: {exception}', array(
 969                                         'exception' => $e
 970                                 ) );
 971                                 $this->errors[] = self::formatExceptionNoComment( $e );
 972                         }
 973                 } else {
 974                         $blobs = array();
 975                 }
 976
 977                 foreach ( $missing as $name ) {
 978                         $states[$name] = 'missing';
 979                 }
 980
 981                 // Generate output
 982                 $isRaw = false;
 983                 foreach ( $modules as $name => $module ) {
 984                         /**
 985                          * @var $module ResourceLoaderModule
 986                          */
 987
 988                         try {
 989                                 $scripts = '';
 990                                 if ( $context->shouldIncludeScripts() ) {
 991                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 992                                         // However, we can't do this if the module doesn't support it
 993                                         // We also can't do this if there is an only= parameter, because we have to give
 994                                         // the module a way to return a load.php URL without causing an infinite loop
 995                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 996                                                 $scripts = $module->getScriptURLsForDebug( $context );
 997                                         } else {
 998                                                 $scripts = $module->getScript( $context );
 999                                                 // rtrim() because there are usually a few line breaks
1000                                                 // after the last ';'. A new line at EOF, a new line
1001                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
1002                                                 if ( is_string( $scripts )
1003                                                         && strlen( $scripts )
1004                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
1005                                                 ) {
1006                                                         // Append semicolon to prevent weird bugs caused by files not
1007                                                         // terminating their statements right (bug 27054)
1008                                                         $scripts .= ";\n";
1009                                                 }
1010                                         }
1011                                 }
1012                                 // Styles
1013                                 $styles = array();
1014                                 if ( $context->shouldIncludeStyles() ) {
1015                                         // Don't create empty stylesheets like array( '' => '' ) for modules
1016                                         // that don't *have* any stylesheets (bug 38024).
1017                                         $stylePairs = $module->getStyles( $context );
1018                                         if ( count( $stylePairs ) ) {
1019                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
1020                                                 // See comment near shouldIncludeScripts() for more details
1021                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
1022                                                         $styles = array(
1023                                                                 'url' => $module->getStyleURLsForDebug( $context )
1024                                                         );
1025                                                 } else {
1026                                                         // Minify CSS before embedding in mw.loader.implement call
1027                                                         // (unless in debug mode)
1028                                                         if ( !$context->getDebug() ) {
1029                                                                 foreach ( $stylePairs as $media => $style ) {
1030                                                                         // Can be either a string or an array of strings.
1031                                                                         if ( is_array( $style ) ) {
1032                                                                                 $stylePairs[$media] = array();
1033                                                                                 foreach ( $style as $cssText ) {
1034                                                                                         if ( is_string( $cssText ) ) {
1035                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
1036                                                                                         }
1037                                                                                 }
1038                                                                         } elseif ( is_string( $style ) ) {
1039                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
1040                                                                         }
1041                                                                 }
1042                                                         }
1043                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
1044                                                         $styles = array(
1045                                                                 'css' => self::makeCombinedStyles( $stylePairs )
1046                                                         );
1047                                                 }
1048                                         }
1049                                 }
1050
1051                                 // Messages
1052                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
1053
1054                                 // Append output
1055                                 switch ( $context->getOnly() ) {
1056                                         case 'scripts':
1057                                                 if ( is_string( $scripts ) ) {
1058                                                         // Load scripts raw...
1059                                                         $out .= $scripts;
1060                                                 } elseif ( is_array( $scripts ) ) {
1061                                                         // ...except when $scripts is an array of URLs
1062                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
1063                                                 }
1064                                                 break;
1065                                         case 'styles':
1066                                                 // We no longer seperate into media, they are all combined now with
1067                                                 // custom media type groups into @media .. {} sections as part of the css string.
1068                                                 // Module returns either an empty array or a numerical array with css strings.
1069                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
1070                                                 break;
1071                                         default:
1072                                                 $out .= self::makeLoaderImplementScript(
1073                                                         $name,
1074                                                         $scripts,
1075                                                         $styles,
1076                                                         new XmlJsCode( $messagesBlob ),
1077                                                         $module->getTemplates()
1078                                                 );
1079                                                 break;
1080                                 }
1081                         } catch ( Exception $e ) {
1082                                 MWExceptionHandler::logException( $e );
1083                                 $this->logger->warning( 'Generating module package failed: {exception}', array(
1084                                         'exception' => $e
1085                                 ) );
1086                                 $this->errors[] = self::formatExceptionNoComment( $e );
1087
1088                                 // Respond to client with error-state instead of module implementation
1089                                 $states[$name] = 'error';
1090                                 unset( $modules[$name] );
1091                         }
1092                         $isRaw |= $module->isRaw();
1093                 }
1094
1095                 // Update module states
1096                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1097                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1098                                 // Set the state of modules loaded as only scripts to ready as
1099                                 // they don't have an mw.loader.implement wrapper that sets the state
1100                                 foreach ( $modules as $name => $module ) {
1101                                         $states[$name] = 'ready';
1102                                 }
1103                         }
1104
1105                         // Set the state of modules we didn't respond to with mw.loader.implement
1106                         if ( count( $states ) ) {
1107                                 $out .= self::makeLoaderStateScript( $states );
1108                         }
1109                 } else {
1110                         if ( count( $states ) ) {
1111                                 $this->errors[] = 'Problematic modules: ' .
1112                                         FormatJson::encode( $states, ResourceLoader::inDebugMode() );
1113                         }
1114                 }
1115
1116                 $enableFilterCache = true;
1117                 if ( count( $modules ) === 1 && reset( $modules ) instanceof ResourceLoaderUserTokensModule ) {
1118                         // If we're building the embedded user.tokens, don't cache (T84960)
1119                         $enableFilterCache = false;
1120                 }
1121
1122                 if ( !$context->getDebug() ) {
1123                         if ( $context->getOnly() === 'styles' ) {
1124                                 $out = $this->filter( 'minify-css', $out );
1125                         } else {
1126                                 $out = $this->filter( 'minify-js', $out, array(
1127                                         'cache' => $enableFilterCache
1128                                 ) );
1129                         }
1130                 }
1131
1132                 return $out;
1133         }
1134
1135         /* Static Methods */
1136
1137         /**
1138          * Return JS code that calls mw.loader.implement with given module properties.
1139          *
1140          * @param string $name Module name
1141          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1142          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1143          *   to CSS files keyed by media type
1144          * @param mixed $messages List of messages associated with this module. May either be an
1145          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1146          *   the same data, wrapped in an XmlJsCode object.
1147          * @param array $templates Keys are name of templates and values are the source of
1148          *   the template.
1149          * @throws MWException
1150          * @return string
1151          */
1152         public static function makeLoaderImplementScript(
1153                 $name, $scripts, $styles, $messages, $templates
1154         ) {
1155                 if ( is_string( $scripts ) ) {
1156                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1157                 } elseif ( !is_array( $scripts ) ) {
1158                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1159                 }
1160                 // mw.loader.implement requires 'styles', 'messages' and 'templates' to be objects (not
1161                 // arrays). json_encode considers empty arrays to be numerical and outputs "[]" instead
1162                 // of "{}". Force them to objects.
1163                 $module = array(
1164                         $name,
1165                         $scripts,
1166                         (object) $styles,
1167                         (object) $messages,
1168                         (object) $templates,
1169                 );
1170                 self::trimArray( $module );
1171
1172                 return Xml::encodeJsCall( 'mw.loader.implement', $module, ResourceLoader::inDebugMode() );
1173         }
1174
1175         /**
1176          * Returns JS code which, when called, will register a given list of messages.
1177          *
1178          * @param mixed $messages Either an associative array mapping message key to value, or a
1179          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1180          * @return string
1181          */
1182         public static function makeMessageSetScript( $messages ) {
1183                 return Xml::encodeJsCall(
1184                         'mw.messages.set',
1185                         array( (object)$messages ),
1186                         ResourceLoader::inDebugMode()
1187                 );
1188         }
1189
1190         /**
1191          * Combines an associative array mapping media type to CSS into a
1192          * single stylesheet with "@media" blocks.
1193          *
1194          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1195          * @return array
1196          */
1197         public static function makeCombinedStyles( array $stylePairs ) {
1198                 $out = array();
1199                 foreach ( $stylePairs as $media => $styles ) {
1200                         // ResourceLoaderFileModule::getStyle can return the styles
1201                         // as a string or an array of strings. This is to allow separation in
1202                         // the front-end.
1203                         $styles = (array)$styles;
1204                         foreach ( $styles as $style ) {
1205                                 $style = trim( $style );
1206                                 // Don't output an empty "@media print { }" block (bug 40498)
1207                                 if ( $style !== '' ) {
1208                                         // Transform the media type based on request params and config
1209                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1210                                         $media = OutputPage::transformCssMedia( $media );
1211
1212                                         if ( $media === '' || $media == 'all' ) {
1213                                                 $out[] = $style;
1214                                         } elseif ( is_string( $media ) ) {
1215                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1216                                         }
1217                                         // else: skip
1218                                 }
1219                         }
1220                 }
1221                 return $out;
1222         }
1223
1224         /**
1225          * Returns a JS call to mw.loader.state, which sets the state of a
1226          * module or modules to a given value. Has two calling conventions:
1227          *
1228          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1229          *         Set the state of a single module called $name to $state
1230          *
1231          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1232          *         Set the state of modules with the given names to the given states
1233          *
1234          * @param string $name
1235          * @param string $state
1236          * @return string
1237          */
1238         public static function makeLoaderStateScript( $name, $state = null ) {
1239                 if ( is_array( $name ) ) {
1240                         return Xml::encodeJsCall(
1241                                 'mw.loader.state',
1242                                 array( $name ),
1243                                 ResourceLoader::inDebugMode()
1244                         );
1245                 } else {
1246                         return Xml::encodeJsCall(
1247                                 'mw.loader.state',
1248                                 array( $name, $state ),
1249                                 ResourceLoader::inDebugMode()
1250                         );
1251                 }
1252         }
1253
1254         /**
1255          * Returns JS code which calls the script given by $script. The script will
1256          * be called with local variables name, version, dependencies and group,
1257          * which will have values corresponding to $name, $version, $dependencies
1258          * and $group as supplied.
1259          *
1260          * @param string $name Module name
1261          * @param string $version Module version hash
1262          * @param array $dependencies List of module names on which this module depends
1263          * @param string $group Group which the module is in.
1264          * @param string $source Source of the module, or 'local' if not foreign.
1265          * @param string $script JavaScript code
1266          * @return string
1267          */
1268         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1269                 $group, $source, $script
1270         ) {
1271                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1272                 return Xml::encodeJsCall(
1273                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1274                         array( $name, $version, $dependencies, $group, $source ),
1275                         ResourceLoader::inDebugMode()
1276                 );
1277         }
1278
1279         private static function isEmptyObject( stdClass $obj ) {
1280                 foreach ( $obj as $key => &$value ) {
1281                         return false;
1282                 }
1283                 return true;
1284         }
1285
1286         /**
1287          * Remove empty values from the end of an array.
1288          *
1289          * Values considered empty:
1290          *
1291          * - null
1292          * - array()
1293          * - new XmlJsCode( '{}' )
1294          * - new stdClass() // (object) array()
1295          *
1296          * @param Array $array
1297          */
1298         private static function trimArray( Array &$array ) {
1299                 $i = count( $array );
1300                 while ( $i-- ) {
1301                         if ( $array[$i] === null
1302                                 || $array[$i] === array()
1303                                 || ( $array[$i] instanceof XmlJsCode && $array[$i]->value === '{}' )
1304                                 || ( $array[$i] instanceof stdClass && self::isEmptyObject( $array[$i] ) )
1305                         ) {
1306                                 unset( $array[$i] );
1307                         } else {
1308                                 break;
1309                         }
1310                 }
1311         }
1312
1313         /**
1314          * Returns JS code which calls mw.loader.register with the given
1315          * parameters. Has three calling conventions:
1316          *
1317          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1318          *        $dependencies, $group, $source, $skip
1319          *     ):
1320          *        Register a single module.
1321          *
1322          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1323          *        Register modules with the given names.
1324          *
1325          *   - ResourceLoader::makeLoaderRegisterScript( array(
1326          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1327          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1328          *        ...
1329          *     ) ):
1330          *        Registers modules with the given names and parameters.
1331          *
1332          * @param string $name Module name
1333          * @param string $version Module version hash
1334          * @param array $dependencies List of module names on which this module depends
1335          * @param string $group Group which the module is in
1336          * @param string $source Source of the module, or 'local' if not foreign
1337          * @param string $skip Script body of the skip function
1338          * @return string
1339          */
1340         public static function makeLoaderRegisterScript( $name, $version = null,
1341                 $dependencies = null, $group = null, $source = null, $skip = null
1342         ) {
1343                 if ( is_array( $name ) ) {
1344                         // Build module name index
1345                         $index = array();
1346                         foreach ( $name as $i => &$module ) {
1347                                 $index[$module[0]] = $i;
1348                         }
1349
1350                         // Transform dependency names into indexes when possible, they will be resolved by
1351                         // mw.loader.register on the other end
1352                         foreach ( $name as &$module ) {
1353                                 if ( isset( $module[2] ) ) {
1354                                         foreach ( $module[2] as &$dependency ) {
1355                                                 if ( isset( $index[$dependency] ) ) {
1356                                                         $dependency = $index[$dependency];
1357                                                 }
1358                                         }
1359                                 }
1360                         }
1361
1362                         array_walk( $name, array( 'self', 'trimArray' ) );
1363
1364                         return Xml::encodeJsCall(
1365                                 'mw.loader.register',
1366                                 array( $name ),
1367                                 ResourceLoader::inDebugMode()
1368                         );
1369                 } else {
1370                         $registration = array( $name, $version, $dependencies, $group, $source, $skip );
1371                         self::trimArray( $registration );
1372                         return Xml::encodeJsCall(
1373                                 'mw.loader.register',
1374                                 $registration,
1375                                 ResourceLoader::inDebugMode()
1376                         );
1377                 }
1378         }
1379
1380         /**
1381          * Returns JS code which calls mw.loader.addSource() with the given
1382          * parameters. Has two calling conventions:
1383          *
1384          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1385          *       Register a single source
1386          *
1387          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1388          *       Register sources with the given IDs and properties.
1389          *
1390          * @param string $id Source ID
1391          * @param array $properties Source properties (see addSource())
1392          * @return string
1393          */
1394         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1395                 if ( is_array( $id ) ) {
1396                         return Xml::encodeJsCall(
1397                                 'mw.loader.addSource',
1398                                 array( $id ),
1399                                 ResourceLoader::inDebugMode()
1400                         );
1401                 } else {
1402                         return Xml::encodeJsCall(
1403                                 'mw.loader.addSource',
1404                                 array( $id, $properties ),
1405                                 ResourceLoader::inDebugMode()
1406                         );
1407                 }
1408         }
1409
1410         /**
1411          * Returns JS code which runs given JS code if the client-side framework is
1412          * present.
1413          *
1414          * @deprecated since 1.25; use makeInlineScript instead
1415          * @param string $script JavaScript code
1416          * @return string
1417          */
1418         public static function makeLoaderConditionalScript( $script ) {
1419                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1420         }
1421
1422         /**
1423          * Construct an inline script tag with given JS code.
1424          *
1425          * The code will be wrapped in a closure, and it will be executed by ResourceLoader
1426          * only if the client has adequate support for MediaWiki JavaScript code.
1427          *
1428          * @param string $script JavaScript code
1429          * @return string HTML
1430          */
1431         public static function makeInlineScript( $script ) {
1432                 $js = self::makeLoaderConditionalScript( $script );
1433                 return Html::inlineScript( $js );
1434         }
1435
1436         /**
1437          * Returns JS code which will set the MediaWiki configuration array to
1438          * the given value.
1439          *
1440          * @param array $configuration List of configuration values keyed by variable name
1441          * @return string
1442          */
1443         public static function makeConfigSetScript( array $configuration ) {
1444                 return Xml::encodeJsCall(
1445                         'mw.config.set',
1446                         array( $configuration ),
1447                         ResourceLoader::inDebugMode()
1448                 );
1449         }
1450
1451         /**
1452          * Convert an array of module names to a packed query string.
1453          *
1454          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1455          * becomes 'foo.bar,baz|bar.baz,quux'
1456          * @param array $modules List of module names (strings)
1457          * @return string Packed query string
1458          */
1459         public static function makePackedModulesString( $modules ) {
1460                 $groups = array(); // array( prefix => array( suffixes ) )
1461                 foreach ( $modules as $module ) {
1462                         $pos = strrpos( $module, '.' );
1463                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1464                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1465                         $groups[$prefix][] = $suffix;
1466                 }
1467
1468                 $arr = array();
1469                 foreach ( $groups as $prefix => $suffixes ) {
1470                         $p = $prefix === '' ? '' : $prefix . '.';
1471                         $arr[] = $p . implode( ',', $suffixes );
1472                 }
1473                 $str = implode( '|', $arr );
1474                 return $str;
1475         }
1476
1477         /**
1478          * Determine whether debug mode was requested
1479          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1480          * @return bool
1481          */
1482         public static function inDebugMode() {
1483                 if ( self::$debugMode === null ) {
1484                         global $wgRequest, $wgResourceLoaderDebug;
1485                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1486                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1487                         );
1488                 }
1489                 return self::$debugMode;
1490         }
1491
1492         /**
1493          * Reset static members used for caching.
1494          *
1495          * Global state and $wgRequest are evil, but we're using it right
1496          * now and sometimes we need to be able to force ResourceLoader to
1497          * re-evaluate the context because it has changed (e.g. in the test suite).
1498          */
1499         public static function clearCache() {
1500                 self::$debugMode = null;
1501         }
1502
1503         /**
1504          * Build a load.php URL
1505          *
1506          * @since 1.24
1507          * @param string $source Name of the ResourceLoader source
1508          * @param ResourceLoaderContext $context
1509          * @param array $extraQuery
1510          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1511          */
1512         public function createLoaderURL( $source, ResourceLoaderContext $context,
1513                 $extraQuery = array()
1514         ) {
1515                 $query = self::createLoaderQuery( $context, $extraQuery );
1516                 $script = $this->getLoadScript( $source );
1517
1518                 // Prevent the IE6 extension check from being triggered (bug 28840)
1519                 // by appending a character that's invalid in Windows extensions ('*')
1520                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1521         }
1522
1523         /**
1524          * Build a load.php URL
1525          * @deprecated since 1.24 Use createLoaderURL() instead
1526          * @param array $modules Array of module names (strings)
1527          * @param string $lang Language code
1528          * @param string $skin Skin name
1529          * @param string|null $user User name. If null, the &user= parameter is omitted
1530          * @param string|null $version Versioning timestamp
1531          * @param bool $debug Whether the request should be in debug mode
1532          * @param string|null $only &only= parameter
1533          * @param bool $printable Printable mode
1534          * @param bool $handheld Handheld mode
1535          * @param array $extraQuery Extra query parameters to add
1536          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1537          */
1538         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1539                 $version = null, $debug = false, $only = null, $printable = false,
1540                 $handheld = false, $extraQuery = array()
1541         ) {
1542                 global $wgLoadScript;
1543
1544                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1545                         $only, $printable, $handheld, $extraQuery
1546                 );
1547
1548                 // Prevent the IE6 extension check from being triggered (bug 28840)
1549                 // by appending a character that's invalid in Windows extensions ('*')
1550                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1551         }
1552
1553         /**
1554          * Helper for createLoaderURL()
1555          *
1556          * @since 1.24
1557          * @see makeLoaderQuery
1558          * @param ResourceLoaderContext $context
1559          * @param array $extraQuery
1560          * @return array
1561          */
1562         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1563                 return self::makeLoaderQuery(
1564                         $context->getModules(),
1565                         $context->getLanguage(),
1566                         $context->getSkin(),
1567                         $context->getUser(),
1568                         $context->getVersion(),
1569                         $context->getDebug(),
1570                         $context->getOnly(),
1571                         $context->getRequest()->getBool( 'printable' ),
1572                         $context->getRequest()->getBool( 'handheld' ),
1573                         $extraQuery
1574                 );
1575         }
1576
1577         /**
1578          * Build a query array (array representation of query string) for load.php. Helper
1579          * function for makeLoaderURL().
1580          *
1581          * @param array $modules
1582          * @param string $lang
1583          * @param string $skin
1584          * @param string $user
1585          * @param string $version
1586          * @param bool $debug
1587          * @param string $only
1588          * @param bool $printable
1589          * @param bool $handheld
1590          * @param array $extraQuery
1591          *
1592          * @return array
1593          */
1594         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1595                 $version = null, $debug = false, $only = null, $printable = false,
1596                 $handheld = false, $extraQuery = array()
1597         ) {
1598                 $query = array(
1599                         'modules' => self::makePackedModulesString( $modules ),
1600                         'lang' => $lang,
1601                         'skin' => $skin,
1602                         'debug' => $debug ? 'true' : 'false',
1603                 );
1604                 if ( $user !== null ) {
1605                         $query['user'] = $user;
1606                 }
1607                 if ( $version !== null ) {
1608                         $query['version'] = $version;
1609                 }
1610                 if ( $only !== null ) {
1611                         $query['only'] = $only;
1612                 }
1613                 if ( $printable ) {
1614                         $query['printable'] = 1;
1615                 }
1616                 if ( $handheld ) {
1617                         $query['handheld'] = 1;
1618                 }
1619                 $query += $extraQuery;
1620
1621                 // Make queries uniform in order
1622                 ksort( $query );
1623                 return $query;
1624         }
1625
1626         /**
1627          * Check a module name for validity.
1628          *
1629          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1630          * at most 255 bytes.
1631          *
1632          * @param string $moduleName Module name to check
1633          * @return bool Whether $moduleName is a valid module name
1634          */
1635         public static function isValidModuleName( $moduleName ) {
1636                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1637         }
1638
1639         /**
1640          * Returns LESS compiler set up for use with MediaWiki
1641          *
1642          * @param Config $config
1643          * @throws MWException
1644          * @since 1.22
1645          * @return lessc
1646          */
1647         public static function getLessCompiler( Config $config ) {
1648                 // When called from the installer, it is possible that a required PHP extension
1649                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1650                 // exception (caught by the installer) to prevent a fatal error later on.
1651                 if ( !class_exists( 'lessc' ) ) {
1652                         throw new MWException( 'MediaWiki requires the lessphp compiler' );
1653                 }
1654                 if ( !function_exists( 'ctype_digit' ) ) {
1655                         throw new MWException( 'lessc requires the Ctype extension' );
1656                 }
1657
1658                 $less = new lessc();
1659                 $less->setPreserveComments( true );
1660                 $less->setVariables( self::getLessVars( $config ) );
1661                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1662                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1663                         $less->registerFunction( $name, $func );
1664                 }
1665                 return $less;
1666         }
1667
1668         /**
1669          * Get global LESS variables.
1670          *
1671          * @param Config $config
1672          * @since 1.22
1673          * @return array Map of variable names to string CSS values.
1674          */
1675         public static function getLessVars( Config $config ) {
1676                 if ( !self::$lessVars ) {
1677                         $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1678                         Hooks::run( 'ResourceLoaderGetLessVars', array( &$lessVars ) );
1679                         // Sort by key to ensure consistent hashing for cache lookups.
1680                         ksort( $lessVars );
1681                         self::$lessVars = $lessVars;
1682                 }
1683                 return self::$lessVars;
1684         }
1685 }