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 documention is on the MediaWiki documentation wiki starting at:
  29  *    http://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32
  33         /* Protected Static Members */
  34         protected static $filterCacheVersion = 7;
  35         protected static $requiredSourceProperties = array( 'loadScript' );
  36
  37         /** Array: List of module name/ResourceLoaderModule object pairs */
  38         protected $modules = array();
  39
  40         /** Associative array mapping module name to info associative array */
  41         protected $moduleInfos = array();
  42
  43         /** Associative array mapping framework ids to a list of names of test suite modules */
  44         /** like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. ) */
  45         protected $testModuleNames = array();
  46
  47         /** array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) **/
  48         protected $sources = array();
  49
  50         /* Protected Methods */
  51
  52         /**
  53          * Loads information stored in the database about modules.
  54          *
  55          * This method grabs modules dependencies from the database and updates modules
  56          * objects.
  57          *
  58          * This is not inside the module code because it is much faster to
  59          * request all of the information at once than it is to have each module
  60          * requests its own information. This sacrifice of modularity yields a substantial
  61          * performance improvement.
  62          *
  63          * @param $modules Array: List of module names to preload information for
  64          * @param $context ResourceLoaderContext: Context to load the information within
  65          */
  66         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  67                 if ( !count( $modules ) ) {
  68                         return; // or else Database*::select() will explode, plus it's cheaper!
  69                 }
  70                 $dbr = wfGetDB( DB_SLAVE );
  71                 $skin = $context->getSkin();
  72                 $lang = $context->getLanguage();
  73
  74                 // Get file dependency information
  75                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  76                                 'md_module' => $modules,
  77                                 'md_skin' => $skin
  78                         ), __METHOD__
  79                 );
  80
  81                 // Set modules' dependencies
  82                 $modulesWithDeps = array();
  83                 foreach ( $res as $row ) {
  84                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  85                                 FormatJson::decode( $row->md_deps, true )
  86                         );
  87                         $modulesWithDeps[] = $row->md_module;
  88                 }
  89
  90                 // Register the absence of a dependency row too
  91                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  92                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  93                 }
  94
  95                 // Get message blob mtimes. Only do this for modules with messages
  96                 $modulesWithMessages = array();
  97                 foreach ( $modules as $name ) {
  98                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  99                                 $modulesWithMessages[] = $name;
 100                         }
 101                 }
 102                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 103                 if ( count( $modulesWithMessages ) ) {
 104                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 105                                         'mr_resource' => $modulesWithMessages,
 106                                         'mr_lang' => $lang
 107                                 ), __METHOD__
 108                         );
 109                         foreach ( $res as $row ) {
 110                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
 111                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 112                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 113                         }
 114                 }
 115                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 116                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 117                 }
 118         }
 119
 120         /**
 121          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 122          *
 123          * Available filters are:
 124          *  - minify-js \see JavaScriptMinifier::minify
 125          *  - minify-css \see CSSMin::minify
 126          *
 127          * If $data is empty, only contains whitespace or the filter was unknown,
 128          * $data is returned unmodified.
 129          *
 130          * @param $filter String: Name of filter to run
 131          * @param $data String: Text to filter, such as JavaScript or CSS text
 132          * @return String: Filtered data, or a comment containing an error message
 133          */
 134         protected function filter( $filter, $data ) {
 135                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 136                 wfProfileIn( __METHOD__ );
 137
 138                 // For empty/whitespace-only data or for unknown filters, don't perform
 139                 // any caching or processing
 140                 if ( trim( $data ) === ''
 141                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 142                 {
 143                         wfProfileOut( __METHOD__ );
 144                         return $data;
 145                 }
 146
 147                 // Try for cache hit
 148                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 149                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 150                 $cache = wfGetCache( CACHE_ANYTHING );
 151                 $cacheEntry = $cache->get( $key );
 152                 if ( is_string( $cacheEntry ) ) {
 153                         wfProfileOut( __METHOD__ );
 154                         return $cacheEntry;
 155                 }
 156
 157                 $result = '';
 158                 // Run the filter - we've already verified one of these will work
 159                 try {
 160                         switch ( $filter ) {
 161                                 case 'minify-js':
 162                                         $result = JavaScriptMinifier::minify( $data,
 163                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 164                                                 $wgResourceLoaderMinifierMaxLineLength
 165                                         );
 166                                         $result .= "\n/* cache key: $key */";
 167                                         break;
 168                                 case 'minify-css':
 169                                         $result = CSSMin::minify( $data );
 170                                         $result .= "\n/* cache key: $key */";
 171                                         break;
 172                         }
 173
 174                         // Save filtered text to Memcached
 175                         $cache->set( $key, $result );
 176                 } catch ( Exception $exception ) {
 177                         // Return exception as a comment
 178                         $result = $this->makeComment( $exception->__toString() );
 179                         $this->hasErrors = true;
 180                 }
 181
 182                 wfProfileOut( __METHOD__ );
 183
 184                 return $result;
 185         }
 186
 187         /* Methods */
 188
 189         /**
 190          * Registers core modules and runs registration hooks.
 191          */
 192         public function __construct() {
 193                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript, $wgEnableJavaScriptTest;
 194
 195                 wfProfileIn( __METHOD__ );
 196
 197                 // Add 'local' source first
 198                 $this->addSource( 'local', array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) ) );
 199
 200                 // Add other sources
 201                 $this->addSource( $wgResourceLoaderSources );
 202
 203                 // Register core modules
 204                 $this->register( include( "$IP/resources/Resources.php" ) );
 205                 // Register extension modules
 206                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 207                 $this->register( $wgResourceModules );
 208
 209                 if ( $wgEnableJavaScriptTest === true ) {
 210                         $this->registerTestModules();
 211                 }
 212
 213
 214                 wfProfileOut( __METHOD__ );
 215         }
 216
 217         /**
 218          * Registers a module with the ResourceLoader system.
 219          *
 220          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 221          * @param $info array Module info array. For backwards compatibility with 1.17alpha,
 222          *   this may also be a ResourceLoaderModule object. Optional when using
 223          *   multiple-registration calling style.
 224          * @throws MWException: If a duplicate module registration is attempted
 225          * @throws MWException: If a module name contains illegal characters (pipes or commas)
 226          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 227          * @return Boolean: False if there were any errors, in which case one or more modules were not
 228          *     registered
 229          */
 230         public function register( $name, $info = null ) {
 231                 wfProfileIn( __METHOD__ );
 232
 233                 // Allow multiple modules to be registered in one call
 234                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 235                 foreach ( $registrations as $name => $info ) {
 236                         // Disallow duplicate registrations
 237                         if ( isset( $this->moduleInfos[$name] ) ) {
 238                                 // A module has already been registered by this name
 239                                 throw new MWException(
 240                                         'ResourceLoader duplicate registration error. ' .
 241                                         'Another module has already been registered as ' . $name
 242                                 );
 243                         }
 244
 245                         // Check $name for validity
 246                         if ( !self::isValidModuleName( $name ) ) {
 247                                 throw new MWException( "ResourceLoader module name '$name' is invalid, see ResourceLoader::isValidModuleName()" );
 248                         }
 249
 250                         // Attach module
 251                         if ( is_object( $info ) ) {
 252                                 // Old calling convention
 253                                 // Validate the input
 254                                 if ( !( $info instanceof ResourceLoaderModule ) ) {
 255                                         throw new MWException( 'ResourceLoader invalid module error. ' .
 256                                                 'Instances of ResourceLoaderModule expected.' );
 257                                 }
 258
 259                                 $this->moduleInfos[$name] = array( 'object' => $info );
 260                                 $info->setName( $name );
 261                                 $this->modules[$name] = $info;
 262                         } else {
 263                                 // New calling convention
 264                                 $this->moduleInfos[$name] = $info;
 265                         }
 266                 }
 267
 268                 wfProfileOut( __METHOD__ );
 269         }
 270
 271         /**
 272          */
 273         public function registerTestModules() {
 274                 global $IP, $wgEnableJavaScriptTest;
 275
 276                 if ( $wgEnableJavaScriptTest !== true ) {
 277                         throw new MWException( 'Attempt to register JavaScript test modules but <tt>$wgEnableJavaScriptTest</tt> is false. Edit your <tt>LocalSettings.php</tt> to enable it.' );
 278                 }
 279
 280                 wfProfileIn( __METHOD__ );
 281
 282                 // Get core test suites
 283                 $testModules = array();
 284                 $testModules['qunit'] = include( "$IP/tests/qunit/QUnitTestResources.php" );
 285                 // Get other test suites (e.g. from extensions)
 286                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 287
 288                 // Add the testrunner (which configures QUnit) to the dependencies.
 289                 // Since it must be ready before any of the test suites are executed.
 290                 foreach( $testModules['qunit'] as $moduleName => $moduleProps ) {
 291                         $testModules['qunit'][$moduleName]['dependencies'][] = 'mediawiki.tests.qunit.testrunner';
 292                 }
 293
 294                 foreach( $testModules as $id => $names ) {
 295                         // Register test modules
 296                         $this->register( $testModules[$id] );
 297
 298                         // Keep track of their names so that they can be loaded together
 299                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 300                 }
 301
 302                 wfProfileOut( __METHOD__ );
 303         }
 304
 305         /**
 306          * Add a foreign source of modules.
 307          *
 308          * Source properties:
 309          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 310          *
 311          * @param $id Mixed: source ID (string), or array( id1 => props1, id2 => props2, ... )
 312          * @param $properties Array: source properties
 313          * @throws MWException
 314          */
 315         public function addSource( $id, $properties = null) {
 316                 // Allow multiple sources to be registered in one call
 317                 if ( is_array( $id ) ) {
 318                         foreach ( $id as $key => $value ) {
 319                                 $this->addSource( $key, $value );
 320                         }
 321                         return;
 322                 }
 323
 324                 // Disallow duplicates
 325                 if ( isset( $this->sources[$id] ) ) {
 326                         throw new MWException(
 327                                 'ResourceLoader duplicate source addition error. ' .
 328                                 'Another source has already been registered as ' . $id
 329                         );
 330                 }
 331
 332                 // Validate properties
 333                 foreach ( self::$requiredSourceProperties as $prop ) {
 334                         if ( !isset( $properties[$prop] ) ) {
 335                                 throw new MWException( "Required property $prop missing from source ID $id" );
 336                         }
 337                 }
 338
 339                 $this->sources[$id] = $properties;
 340         }
 341
 342         /**
 343          * Get a list of module names
 344          *
 345          * @return Array: List of module names
 346          */
 347         public function getModuleNames() {
 348                 return array_keys( $this->moduleInfos );
 349         }
 350
 351         /**
 352          * Get a list of test module names for one (or all) frameworks.
 353          * If the given framework id is unknkown, or if the in-object variable is not an array,
 354          * then it will return an empty array.
 355          *
 356          * @param $framework String: Optional. Get only the test module names for one
 357          * particular framework.
 358          * @return Array
 359          */
 360         public function getTestModuleNames( $framework = 'all' ) {
 361                 /// @TODO: api siteinfo prop testmodulenames modulenames
 362                 if ( $framework == 'all' ) {
 363                         return $this->testModuleNames;
 364                 } elseif ( isset( $this->testModuleNames[$framework] ) && is_array( $this->testModuleNames[$framework] ) ) {
 365                         return $this->testModuleNames[$framework];
 366                 } else {
 367                         return array();
 368                 }
 369         }
 370
 371         /**
 372          * Get the ResourceLoaderModule object for a given module name.
 373          *
 374          * @param $name String: Module name
 375          * @return ResourceLoaderModule if module has been registered, null otherwise
 376          */
 377         public function getModule( $name ) {
 378                 if ( !isset( $this->modules[$name] ) ) {
 379                         if ( !isset( $this->moduleInfos[$name] ) ) {
 380                                 // No such module
 381                                 return null;
 382                         }
 383                         // Construct the requested object
 384                         $info = $this->moduleInfos[$name];
 385                         if ( isset( $info['object'] ) ) {
 386                                 // Object given in info array
 387                                 $object = $info['object'];
 388                         } else {
 389                                 if ( !isset( $info['class'] ) ) {
 390                                         $class = 'ResourceLoaderFileModule';
 391                                 } else {
 392                                         $class = $info['class'];
 393                                 }
 394                                 $object = new $class( $info );
 395                         }
 396                         $object->setName( $name );
 397                         $this->modules[$name] = $object;
 398                 }
 399
 400                 return $this->modules[$name];
 401         }
 402
 403         /**
 404          * Get the list of sources
 405          *
 406          * @return Array: array( id => array of properties, .. )
 407          */
 408         public function getSources() {
 409                 return $this->sources;
 410         }
 411
 412         /**
 413          * Outputs a response to a resource load-request, including a content-type header.
 414          *
 415          * @param $context ResourceLoaderContext: Context in which a response should be formed
 416          */
 417         public function respond( ResourceLoaderContext $context ) {
 418                 global $wgCacheEpoch, $wgUseFileCache;
 419
 420                 // Use file cache if enabled and available...
 421                 if ( $wgUseFileCache ) {
 422                         $fileCache = ResourceFileCache::newFromContext( $context );
 423                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 424                                 return; // output handled
 425                         }
 426                 }
 427
 428                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 429                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 430                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 431                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 432                 // the whole thing in our own output buffer to be sure the active buffer
 433                 // doesn't use ob_gzhandler.
 434                 // See http://bugs.php.net/bug.php?id=36514
 435                 ob_start();
 436
 437                 wfProfileIn( __METHOD__ );
 438                 $errors = '';
 439                 $this->hasErrors = false;
 440
 441                 // Split requested modules into two groups, modules and missing
 442                 $modules = array();
 443                 $missing = array();
 444                 foreach ( $context->getModules() as $name ) {
 445                         if ( isset( $this->moduleInfos[$name] ) ) {
 446                                 $module = $this->getModule( $name );
 447                                 // Do not allow private modules to be loaded from the web.
 448                                 // This is a security issue, see bug 34907.
 449                                 if ( $module->getGroup() === 'private' ) {
 450                                         $errors .= $this->makeComment( "Cannot show private module \"$name\"" );
 451                                         $this->hasErrors = true;
 452                                         continue;
 453                                 }
 454                                 $modules[$name] = $module;
 455                         } else {
 456                                 $missing[] = $name;
 457                         }
 458                 }
 459
 460                 // Preload information needed to the mtime calculation below
 461                 try {
 462                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 463                 } catch( Exception $e ) {
 464                         // Add exception to the output as a comment
 465                         $errors .= $this->makeComment( $e->__toString() );
 466                         $this->hasErrors = true;
 467                 }
 468
 469                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 470
 471                 // To send Last-Modified and support If-Modified-Since, we need to detect
 472                 // the last modified time
 473                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 474                 foreach ( $modules as $module ) {
 475                         /**
 476                          * @var $module ResourceLoaderModule
 477                          */
 478                         try {
 479                                 // Calculate maximum modified time
 480                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 481                         } catch ( Exception $e ) {
 482                                 // Add exception to the output as a comment
 483                                 $errors .= $this->makeComment( $e->__toString() );
 484                                 $this->hasErrors = true;
 485                         }
 486                 }
 487
 488                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 489
 490                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 491                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 492                         wfProfileOut( __METHOD__ );
 493                         return; // output handled (buffers cleared)
 494                 }
 495
 496                 // Generate a response
 497                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 498
 499                 // Prepend comments indicating exceptions
 500                 $response = $errors . $response;
 501
 502                 // Capture any PHP warnings from the output buffer and append them to the
 503                 // response in a comment if we're in debug mode.
 504                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 505                         $response = $this->makeComment( $warnings ) . $response;
 506                         $this->hasErrors = true;
 507                 }
 508
 509                 // Save response to file cache unless there are errors
 510                 if ( isset( $fileCache ) && !$errors && !$missing ) {
 511                         // Cache single modules...and other requests if there are enough hits
 512                         if ( ResourceFileCache::useFileCache( $context ) ) {
 513                                 if ( $fileCache->isCacheWorthy() ) {
 514                                         $fileCache->saveText( $response );
 515                                 } else {
 516                                         $fileCache->incrMissesRecent( $context->getRequest() );
 517                                 }
 518                         }
 519                 }
 520
 521                 // Send content type and cache related headers
 522                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 523
 524                 // Remove the output buffer and output the response
 525                 ob_end_clean();
 526                 echo $response;
 527
 528                 wfProfileOut( __METHOD__ );
 529         }
 530
 531         /**
 532          * Send content type and last modified headers to the client.
 533          * @param $context ResourceLoaderContext
 534          * @param $mtime string TS_MW timestamp to use for last-modified
 535          * @param $error bool Whether there are commented-out errors in the response
 536          * @return void
 537          */
 538         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 539                 global $wgResourceLoaderMaxage;
 540                 // If a version wasn't specified we need a shorter expiry time for updates
 541                 // to propagate to clients quickly
 542                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 543                 if ( is_null( $context->getVersion() ) || $errors ) {
 544                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 545                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 546                 // If a version was specified we can use a longer expiry time since changing
 547                 // version numbers causes cache misses
 548                 } else {
 549                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 550                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 551                 }
 552                 if ( $context->getOnly() === 'styles' ) {
 553                         header( 'Content-Type: text/css; charset=utf-8' );
 554                 } else {
 555                         header( 'Content-Type: text/javascript; charset=utf-8' );
 556                 }
 557                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 558                 if ( $context->getDebug() ) {
 559                         // Do not cache debug responses
 560                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 561                         header( 'Pragma: no-cache' );
 562                 } else {
 563                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 564                         $exp = min( $maxage, $smaxage );
 565                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 566                 }
 567         }
 568
 569         /**
 570          * If there's an If-Modified-Since header, respond with a 304 appropriately
 571          * and clear out the output buffer. If the client cache is too old then do nothing.
 572          * @param $context ResourceLoaderContext
 573          * @param $mtime string The TS_MW timestamp to check the header against
 574          * @return bool True iff 304 header sent and output handled
 575          */
 576         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 577                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 578                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 579                 // so we get a valid timestamp.
 580                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 581                 // Never send 304s in debug mode
 582                 if ( $ims !== false && !$context->getDebug() ) {
 583                         $imsTS = strtok( $ims, ';' );
 584                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 585                                 // There's another bug in ob_gzhandler (see also the comment at
 586                                 // the top of this function) that causes it to gzip even empty
 587                                 // responses, meaning it's impossible to produce a truly empty
 588                                 // response (because the gzip header is always there). This is
 589                                 // a problem because 304 responses have to be completely empty
 590                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 591                                 // See also http://bugs.php.net/bug.php?id=51579
 592                                 // To work around this, we tear down all output buffering before
 593                                 // sending the 304.
 594                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 595                                 // no matter how often we call ob_get_clean(), so instead of doing
 596                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 597                                 // we have to be safe here and avoid an infinite loop.
 598                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 599                                         ob_end_clean();
 600                                 }
 601
 602                                 header( 'HTTP/1.0 304 Not Modified' );
 603                                 header( 'Status: 304 Not Modified' );
 604                                 return true;
 605                         }
 606                 }
 607                 return false;
 608         }
 609
 610         /**
 611          * Send out code for a response from file cache if possible
 612          *
 613          * @param $fileCache ResourceFileCache: Cache object for this request URL
 614          * @param $context ResourceLoaderContext: Context in which to generate a response
 615          * @return bool If this found a cache file and handled the response
 616          */
 617         protected function tryRespondFromFileCache(
 618                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 619         ) {
 620                 global $wgResourceLoaderMaxage;
 621                 // Buffer output to catch warnings.
 622                 ob_start();
 623                 // Get the maximum age the cache can be
 624                 $maxage = is_null( $context->getVersion() )
 625                         ? $wgResourceLoaderMaxage['unversioned']['server']
 626                         : $wgResourceLoaderMaxage['versioned']['server'];
 627                 // Minimum timestamp the cache file must have
 628                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 629                 if ( !$good ) {
 630                         try { // RL always hits the DB on file cache miss...
 631                                 wfGetDB( DB_SLAVE );
 632                         } catch( DBConnectionError $e ) { // ...check if we need to fallback to cache
 633                                 $good = $fileCache->isCacheGood(); // cache existence check
 634                         }
 635                 }
 636                 if ( $good ) {
 637                         $ts = $fileCache->cacheTimestamp();
 638                         // Send content type and cache headers
 639                         $this->sendResponseHeaders( $context, $ts, false );
 640                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 641                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 642                                 return false; // output handled (buffers cleared)
 643                         }
 644                         $response = $fileCache->fetchText();
 645                         // Capture any PHP warnings from the output buffer and append them to the
 646                         // response in a comment if we're in debug mode.
 647                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 648                                 $response = "/*\n$warnings\n*/\n" . $response;
 649                         }
 650                         // Remove the output buffer and output the response
 651                         ob_end_clean();
 652                         echo $response . "\n/* Cached {$ts} */";
 653                         return true; // cache hit
 654                 }
 655                 // Clear buffer
 656                 ob_end_clean();
 657
 658                 return false; // cache miss
 659         }
 660
 661         protected function makeComment( $text ) {
 662                 $encText = str_replace( '*/', '* /', $text );
 663                 return "/*\n$encText\n*/\n";
 664         }
 665
 666         /**
 667          * Generates code for a response
 668          *
 669          * @param $context ResourceLoaderContext: Context in which to generate a response
 670          * @param $modules Array: List of module objects keyed by module name
 671          * @param $missing Array: List of unavailable modules (optional)
 672          * @return String: Response data
 673          */
 674         public function makeModuleResponse( ResourceLoaderContext $context,
 675                 array $modules, $missing = array() )
 676         {
 677                 $out = '';
 678                 $exceptions = '';
 679                 if ( $modules === array() && $missing === array() ) {
 680                         return '/* No modules requested. Max made me put this here */';
 681                 }
 682
 683                 wfProfileIn( __METHOD__ );
 684                 // Pre-fetch blobs
 685                 if ( $context->shouldIncludeMessages() ) {
 686                         try {
 687                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 688                         } catch ( Exception $e ) {
 689                                 // Add exception to the output as a comment
 690                                 $exceptions .= $this->makeComment( $e->__toString() );
 691                                 $this->hasErrors = true;
 692                         }
 693                 } else {
 694                         $blobs = array();
 695                 }
 696
 697                 // Generate output
 698                 $isRaw = false;
 699                 foreach ( $modules as $name => $module ) {
 700                         /**
 701                          * @var $module ResourceLoaderModule
 702                          */
 703
 704                         wfProfileIn( __METHOD__ . '-' . $name );
 705                         try {
 706                                 $scripts = '';
 707                                 if ( $context->shouldIncludeScripts() ) {
 708                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 709                                         // However, we can't do this if the module doesn't support it
 710                                         // We also can't do this if there is an only= parameter, because we have to give
 711                                         // the module a way to return a load.php URL without causing an infinite loop
 712                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 713                                                 $scripts = $module->getScriptURLsForDebug( $context );
 714                                         } else {
 715                                                 $scripts = $module->getScript( $context );
 716                                                 if ( is_string( $scripts ) && strlen( $scripts ) && substr( $scripts, -1 ) !== ';' ) {
 717                                                         // bug 27054: Append semicolon to prevent weird bugs
 718                                                         // caused by files not terminating their statements right
 719                                                         $scripts .= ";\n";
 720                                                 }
 721                                         }
 722                                 }
 723                                 // Styles
 724                                 $styles = array();
 725                                 if ( $context->shouldIncludeStyles() ) {
 726                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 727                                         // that don't *have* any stylesheets (bug 38024).
 728                                         $stylePairs = $module->getStyles( $context );
 729                                         if ( count ( $stylePairs ) ) {
 730                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 731                                                 // See comment near shouldIncludeScripts() for more details
 732                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 733                                                         $styles = array(
 734                                                                 'url' => $module->getStyleURLsForDebug( $context )
 735                                                         );
 736                                                 } else {
 737                                                         // Minify CSS before embedding in mw.loader.implement call
 738                                                         // (unless in debug mode)
 739                                                         if ( !$context->getDebug() ) {
 740                                                                 foreach ( $stylePairs as $media => $style ) {
 741                                                                         // Can be either a string or an array of strings.
 742                                                                         if ( is_array( $style ) ) {
 743                                                                                 $stylePairs[$media] = array();
 744                                                                                 foreach ( $style as $cssText ) {
 745                                                                                         if ( is_string( $cssText ) ) {
 746                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 747                                                                                         }
 748                                                                                 }
 749                                                                         } elseif ( is_string( $style ) ) {
 750                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 751                                                                         }
 752                                                                 }
 753                                                         }
 754                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 755                                                         $styles = array(
 756                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 757                                                         );
 758                                                 }
 759                                         }
 760                                 }
 761
 762                                 // Messages
 763                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 764
 765                                 // Append output
 766                                 switch ( $context->getOnly() ) {
 767                                         case 'scripts':
 768                                                 if ( is_string( $scripts ) ) {
 769                                                         // Load scripts raw...
 770                                                         $out .= $scripts;
 771                                                 } elseif ( is_array( $scripts ) ) {
 772                                                         // ...except when $scripts is an array of URLs
 773                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 774                                                 }
 775                                                 break;
 776                                         case 'styles':
 777                                                 // We no longer seperate into media, they are all combined now with
 778                                                 // custom media type groups into @media .. {} sections as part of the css string.
 779                                                 // Module returns either an empty array or a numerical array with css strings.
 780                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 781                                                 break;
 782                                         case 'messages':
 783                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 784                                                 break;
 785                                         default:
 786                                                 $out .= self::makeLoaderImplementScript(
 787                                                         $name,
 788                                                         $scripts,
 789                                                         $styles,
 790                                                         new XmlJsCode( $messagesBlob )
 791                                                 );
 792                                                 break;
 793                                 }
 794                         } catch ( Exception $e ) {
 795                                 // Add exception to the output as a comment
 796                                 $exceptions .= $this->makeComment( $e->__toString() );
 797                                 $this->hasErrors = true;
 798
 799                                 // Register module as missing
 800                                 $missing[] = $name;
 801                                 unset( $modules[$name] );
 802                         }
 803                         $isRaw |= $module->isRaw();
 804                         wfProfileOut( __METHOD__ . '-' . $name );
 805                 }
 806
 807                 // Update module states
 808                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
 809                         // Set the state of modules loaded as only scripts to ready
 810                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
 811                                 $out .= self::makeLoaderStateScript(
 812                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 813                         }
 814                         // Set the state of modules which were requested but unavailable as missing
 815                         if ( is_array( $missing ) && count( $missing ) ) {
 816                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 817                         }
 818                 }
 819
 820                 if ( !$context->getDebug() ) {
 821                         if ( $context->getOnly() === 'styles' ) {
 822                                 $out = $this->filter( 'minify-css', $out );
 823                         } else {
 824                                 $out = $this->filter( 'minify-js', $out );
 825                         }
 826                 }
 827
 828                 wfProfileOut( __METHOD__ );
 829                 return $exceptions . $out;
 830         }
 831
 832         /* Static Methods */
 833
 834         /**
 835          * Returns JS code to call to mw.loader.implement for a module with
 836          * given properties.
 837          *
 838          * @param $name string Module name
 839          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 840          * @param $styles Mixed: Array of CSS strings keyed by media type, or an array of lists of URLs to
 841          * CSS files keyed by media type
 842          * @param $messages Mixed: List of messages associated with this module. May either be an
 843          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 844          *     the same data, wrapped in an XmlJsCode object.
 845          *
 846          * @throws MWException
 847          * @return string
 848          */
 849         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 850                 if ( is_string( $scripts ) ) {
 851                         $scripts = new XmlJsCode( "function () {\n{$scripts}\n}" );
 852                 } elseif ( !is_array( $scripts ) ) {
 853                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 854                 }
 855                 return Xml::encodeJsCall(
 856                         'mw.loader.implement',
 857                         array(
 858                                 $name,
 859                                 $scripts,
 860                                 // Force objects. mw.loader.implement requires them to be javascript objects.
 861                                 // Although these variables are associative arrays, which become javascript
 862                                 // objects through json_encode. In many cases they will be empty arrays, and
 863                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
 864                                 // output javascript "[]" instead of "{}". This fixes that.
 865                                 (object)$styles,
 866                                 (object)$messages
 867                         ) );
 868         }
 869
 870         /**
 871          * Returns JS code which, when called, will register a given list of messages.
 872          *
 873          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 874          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 875          *
 876          * @return string
 877          */
 878         public static function makeMessageSetScript( $messages ) {
 879                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 880         }
 881
 882         /**
 883          * Combines an associative array mapping media type to CSS into a
 884          * single stylesheet with "@media" blocks.
 885          *
 886          * @param $stylePairs Array: Array keyed by media type containing (arrays of) CSS strings.
 887          *
 888          * @return Array
 889          */
 890         private static function makeCombinedStyles( array $stylePairs ) {
 891                 $out = array();
 892                 foreach ( $stylePairs as $media => $styles ) {
 893                         // ResourceLoaderFileModule::getStyle can return the styles
 894                         // as a string or an array of strings. This is to allow separation in
 895                         // the front-end.
 896                         $styles = (array) $styles;
 897                         foreach ( $styles as $style ) {
 898                                 $style = trim( $style );
 899                                 // Don't output an empty "@media print { }" block (bug 40498)
 900                                 if ( $style !== '' ) {
 901                                         // Transform the media type based on request params and config
 902                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 903                                         $media = OutputPage::transformCssMedia( $media );
 904
 905                                         if ( $media === '' || $media == 'all' ) {
 906                                                 $out[] = $style;
 907                                         } else if ( is_string( $media ) ) {
 908                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
 909                                         }
 910                                         // else: skip
 911                                 }
 912                         }
 913                 }
 914                 return $out;
 915         }
 916
 917         /**
 918          * Returns a JS call to mw.loader.state, which sets the state of a
 919          * module or modules to a given value. Has two calling conventions:
 920          *
 921          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 922          *         Set the state of a single module called $name to $state
 923          *
 924          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 925          *         Set the state of modules with the given names to the given states
 926          *
 927          * @param $name string
 928          * @param $state
 929          *
 930          * @return string
 931          */
 932         public static function makeLoaderStateScript( $name, $state = null ) {
 933                 if ( is_array( $name ) ) {
 934                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 935                 } else {
 936                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 937                 }
 938         }
 939
 940         /**
 941          * Returns JS code which calls the script given by $script. The script will
 942          * be called with local variables name, version, dependencies and group,
 943          * which will have values corresponding to $name, $version, $dependencies
 944          * and $group as supplied.
 945          *
 946          * @param $name String: Module name
 947          * @param $version Integer: Module version number as a timestamp
 948          * @param $dependencies Array: List of module names on which this module depends
 949          * @param $group String: Group which the module is in.
 950          * @param $source String: Source of the module, or 'local' if not foreign.
 951          * @param $script String: JavaScript code
 952          *
 953          * @return string
 954          */
 955         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 956                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 957                 return Xml::encodeJsCall(
 958                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
 959                         array( $name, $version, $dependencies, $group, $source ) );
 960         }
 961
 962         /**
 963          * Returns JS code which calls mw.loader.register with the given
 964          * parameters. Has three calling conventions:
 965          *
 966          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 967          *       Register a single module.
 968          *
 969          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 970          *       Register modules with the given names.
 971          *
 972          *   - ResourceLoader::makeLoaderRegisterScript( array(
 973          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 974          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 975          *        ...
 976          *     ) ):
 977          *        Registers modules with the given names and parameters.
 978          *
 979          * @param $name String: Module name
 980          * @param $version Integer: Module version number as a timestamp
 981          * @param $dependencies Array: List of module names on which this module depends
 982          * @param $group String: group which the module is in.
 983          * @param $source String: source of the module, or 'local' if not foreign
 984          *
 985          * @return string
 986          */
 987         public static function makeLoaderRegisterScript( $name, $version = null,
 988                 $dependencies = null, $group = null, $source = null )
 989         {
 990                 if ( is_array( $name ) ) {
 991                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 992                 } else {
 993                         $version = (int) $version > 1 ? (int) $version : 1;
 994                         return Xml::encodeJsCall( 'mw.loader.register',
 995                                 array( $name, $version, $dependencies, $group, $source ) );
 996                 }
 997         }
 998
 999         /**
1000          * Returns JS code which calls mw.loader.addSource() with the given
1001          * parameters. Has two calling conventions:
1002          *
1003          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1004          *       Register a single source
1005          *
1006          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
1007          *       Register sources with the given IDs and properties.
1008          *
1009          * @param $id String: source ID
1010          * @param $properties Array: source properties (see addSource())
1011          *
1012          * @return string
1013          */
1014         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1015                 if ( is_array( $id ) ) {
1016                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
1017                 } else {
1018                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
1019                 }
1020         }
1021
1022         /**
1023          * Returns JS code which runs given JS code if the client-side framework is
1024          * present.
1025          *
1026          * @param $script String: JavaScript code
1027          *
1028          * @return string
1029          */
1030         public static function makeLoaderConditionalScript( $script ) {
1031                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1032         }
1033
1034         /**
1035          * Returns JS code which will set the MediaWiki configuration array to
1036          * the given value.
1037          *
1038          * @param $configuration Array: List of configuration values keyed by variable name
1039          *
1040          * @return string
1041          */
1042         public static function makeConfigSetScript( array $configuration ) {
1043                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
1044         }
1045
1046         /**
1047          * Convert an array of module names to a packed query string.
1048          *
1049          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1050          * becomes 'foo.bar,baz|bar.baz,quux'
1051          * @param $modules array of module names (strings)
1052          * @return string Packed query string
1053          */
1054         public static function makePackedModulesString( $modules ) {
1055                 $groups = array(); // array( prefix => array( suffixes ) )
1056                 foreach ( $modules as $module ) {
1057                         $pos = strrpos( $module, '.' );
1058                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1059                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1060                         $groups[$prefix][] = $suffix;
1061                 }
1062
1063                 $arr = array();
1064                 foreach ( $groups as $prefix => $suffixes ) {
1065                         $p = $prefix === '' ? '' : $prefix . '.';
1066                         $arr[] = $p . implode( ',', $suffixes );
1067                 }
1068                 $str = implode( '|', $arr );
1069                 return $str;
1070         }
1071
1072         /**
1073          * Determine whether debug mode was requested
1074          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1075          * @return bool
1076          */
1077         public static function inDebugMode() {
1078                 global $wgRequest, $wgResourceLoaderDebug;
1079                 static $retval = null;
1080                 if ( !is_null( $retval ) ) {
1081                         return $retval;
1082                 }
1083                 return $retval = $wgRequest->getFuzzyBool( 'debug',
1084                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
1085         }
1086
1087         /**
1088          * Build a load.php URL
1089          * @param $modules array of module names (strings)
1090          * @param $lang string Language code
1091          * @param $skin string Skin name
1092          * @param $user string|null User name. If null, the &user= parameter is omitted
1093          * @param $version string|null Versioning timestamp
1094          * @param $debug bool Whether the request should be in debug mode
1095          * @param $only string|null &only= parameter
1096          * @param $printable bool Printable mode
1097          * @param $handheld bool Handheld mode
1098          * @param $extraQuery array Extra query parameters to add
1099          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1100          */
1101         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1102                         $printable = false, $handheld = false, $extraQuery = array() ) {
1103                 global $wgLoadScript;
1104                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1105                         $only, $printable, $handheld, $extraQuery
1106                 );
1107
1108                 // Prevent the IE6 extension check from being triggered (bug 28840)
1109                 // by appending a character that's invalid in Windows extensions ('*')
1110                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1111         }
1112
1113         /**
1114          * Build a query array (array representation of query string) for load.php. Helper
1115          * function for makeLoaderURL().
1116          * @return array
1117          */
1118         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1119                         $printable = false, $handheld = false, $extraQuery = array() ) {
1120                 $query = array(
1121                         'modules' => self::makePackedModulesString( $modules ),
1122                         'lang' => $lang,
1123                         'skin' => $skin,
1124                         'debug' => $debug ? 'true' : 'false',
1125                 );
1126                 if ( $user !== null ) {
1127                         $query['user'] = $user;
1128                 }
1129                 if ( $version !== null ) {
1130                         $query['version'] = $version;
1131                 }
1132                 if ( $only !== null ) {
1133                         $query['only'] = $only;
1134                 }
1135                 if ( $printable ) {
1136                         $query['printable'] = 1;
1137                 }
1138                 if ( $handheld ) {
1139                         $query['handheld'] = 1;
1140                 }
1141                 $query += $extraQuery;
1142
1143                 // Make queries uniform in order
1144                 ksort( $query );
1145                 return $query;
1146         }
1147
1148         /**
1149          * Check a module name for validity.
1150          *
1151          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1152          * at most 255 bytes.
1153          *
1154          * @param $moduleName string Module name to check
1155          * @return bool Whether $moduleName is a valid module name
1156          */
1157         public static function isValidModuleName( $moduleName ) {
1158                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1159         }
1160 }