includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @author Roan Kattouw
  20  * @author Trevor Parscal
  21  */
  22
  23 /**
  24  * Dynamic JavaScript and CSS resource loading system.
  25  *
  26  * Most of the documention is on the MediaWiki documentation wiki starting at:
  27  *    http://www.mediawiki.org/wiki/ResourceLoader
  28  */
  29 class ResourceLoader {
  30
  31         /* Protected Static Members */
  32         protected static $filterCacheVersion = 7;
  33         protected static $requiredSourceProperties = array( 'loadScript' );
  34
  35         /** Array: List of module name/ResourceLoaderModule object pairs */
  36         protected $modules = array();
  37
  38         /** Associative array mapping module name to info associative array */
  39         protected $moduleInfos = array();
  40
  41         /** Associative array mapping framework ids to a list of names of test suite modules */
  42         /** like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. ) */
  43         protected $testModuleNames = array();
  44
  45         /** array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) **/
  46         protected $sources = array();
  47
  48         /* Protected Methods */
  49
  50         /**
  51          * Loads information stored in the database about modules.
  52          *
  53          * This method grabs modules dependencies from the database and updates modules
  54          * objects.
  55          *
  56          * This is not inside the module code because it is much faster to
  57          * request all of the information at once than it is to have each module
  58          * requests its own information. This sacrifice of modularity yields a substantial
  59          * performance improvement.
  60          *
  61          * @param $modules Array: List of module names to preload information for
  62          * @param $context ResourceLoaderContext: Context to load the information within
  63          */
  64         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  65                 if ( !count( $modules ) ) {
  66                         return; // or else Database*::select() will explode, plus it's cheaper!
  67                 }
  68                 $dbr = wfGetDB( DB_SLAVE );
  69                 $skin = $context->getSkin();
  70                 $lang = $context->getLanguage();
  71
  72                 // Get file dependency information
  73                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  74                                 'md_module' => $modules,
  75                                 'md_skin' => $skin
  76                         ), __METHOD__
  77                 );
  78
  79                 // Set modules' dependencies
  80                 $modulesWithDeps = array();
  81                 foreach ( $res as $row ) {
  82                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  83                                 FormatJson::decode( $row->md_deps, true )
  84                         );
  85                         $modulesWithDeps[] = $row->md_module;
  86                 }
  87
  88                 // Register the absence of a dependency row too
  89                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  90                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  91                 }
  92
  93                 // Get message blob mtimes. Only do this for modules with messages
  94                 $modulesWithMessages = array();
  95                 foreach ( $modules as $name ) {
  96                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  97                                 $modulesWithMessages[] = $name;
  98                         }
  99                 }
 100                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 101                 if ( count( $modulesWithMessages ) ) {
 102                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 103                                         'mr_resource' => $modulesWithMessages,
 104                                         'mr_lang' => $lang
 105                                 ), __METHOD__
 106                         );
 107                         foreach ( $res as $row ) {
 108                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
 109                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 110                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 111                         }
 112                 }
 113                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 114                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 115                 }
 116         }
 117
 118         /**
 119          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 120          *
 121          * Available filters are:
 122          *  - minify-js \see JavaScriptMinifier::minify
 123          *  - minify-css \see CSSMin::minify
 124          *
 125          * If $data is empty, only contains whitespace or the filter was unknown,
 126          * $data is returned unmodified.
 127          *
 128          * @param $filter String: Name of filter to run
 129          * @param $data String: Text to filter, such as JavaScript or CSS text
 130          * @return String: Filtered data, or a comment containing an error message
 131          */
 132         protected function filter( $filter, $data ) {
 133                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 134                 wfProfileIn( __METHOD__ );
 135
 136                 // For empty/whitespace-only data or for unknown filters, don't perform
 137                 // any caching or processing
 138                 if ( trim( $data ) === ''
 139                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 140                 {
 141                         wfProfileOut( __METHOD__ );
 142                         return $data;
 143                 }
 144
 145                 // Try for cache hit
 146                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 147                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 148                 $cache = wfGetCache( CACHE_ANYTHING );
 149                 $cacheEntry = $cache->get( $key );
 150                 if ( is_string( $cacheEntry ) ) {
 151                         wfProfileOut( __METHOD__ );
 152                         return $cacheEntry;
 153                 }
 154
 155                 $result = '';
 156                 // Run the filter - we've already verified one of these will work
 157                 try {
 158                         switch ( $filter ) {
 159                                 case 'minify-js':
 160                                         $result = JavaScriptMinifier::minify( $data,
 161                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 162                                                 $wgResourceLoaderMinifierMaxLineLength
 163                                         );
 164                                         $result .= "\n\n/* cache key: $key */\n";
 165                                         break;
 166                                 case 'minify-css':
 167                                         $result = CSSMin::minify( $data );
 168                                         $result .= "\n\n/* cache key: $key */\n";
 169                                         break;
 170                         }
 171
 172                         // Save filtered text to Memcached
 173                         $cache->set( $key, $result );
 174                 } catch ( Exception $exception ) {
 175                         // Return exception as a comment
 176                         $result = "/*\n{$exception->__toString()}\n*/\n";
 177                 }
 178
 179                 wfProfileOut( __METHOD__ );
 180
 181                 return $result;
 182         }
 183
 184         /* Methods */
 185
 186         /**
 187          * Registers core modules and runs registration hooks.
 188          */
 189         public function __construct() {
 190                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript, $wgEnableJavaScriptTest;
 191
 192                 wfProfileIn( __METHOD__ );
 193
 194                 // Add 'local' source first
 195                 $this->addSource( 'local', array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) ) );
 196
 197                 // Add other sources
 198                 $this->addSource( $wgResourceLoaderSources );
 199
 200                 // Register core modules
 201                 $this->register( include( "$IP/resources/Resources.php" ) );
 202                 // Register extension modules
 203                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 204                 $this->register( $wgResourceModules );
 205
 206                 if ( $wgEnableJavaScriptTest === true ) {
 207                         $this->registerTestModules();
 208                 }
 209
 210
 211                 wfProfileOut( __METHOD__ );
 212         }
 213
 214         /**
 215          * Registers a module with the ResourceLoader system.
 216          *
 217          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 218          * @param $info array Module info array. For backwards compatibility with 1.17alpha,
 219          *   this may also be a ResourceLoaderModule object. Optional when using
 220          *   multiple-registration calling style.
 221          * @throws MWException: If a duplicate module registration is attempted
 222          * @throws MWException: If a module name contains illegal characters (pipes or commas)
 223          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 224          * @return Boolean: False if there were any errors, in which case one or more modules were not
 225          *     registered
 226          */
 227         public function register( $name, $info = null ) {
 228                 wfProfileIn( __METHOD__ );
 229
 230                 // Allow multiple modules to be registered in one call
 231                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 232                 foreach ( $registrations as $name => $info ) {
 233                         // Disallow duplicate registrations
 234                         if ( isset( $this->moduleInfos[$name] ) ) {
 235                                 // A module has already been registered by this name
 236                                 throw new MWException(
 237                                         'ResourceLoader duplicate registration error. ' .
 238                                         'Another module has already been registered as ' . $name
 239                                 );
 240                         }
 241
 242                         // Check $name for illegal characters
 243                         if ( preg_match( '/[|,!]/', $name ) ) {
 244                                 throw new MWException( "ResourceLoader module name '$name' is invalid. Names may not contain pipes (|), commas (,) or exclamation marks (!)" );
 245                         }
 246
 247                         // Attach module
 248                         if ( is_object( $info ) ) {
 249                                 // Old calling convention
 250                                 // Validate the input
 251                                 if ( !( $info instanceof ResourceLoaderModule ) ) {
 252                                         throw new MWException( 'ResourceLoader invalid module error. ' .
 253                                                 'Instances of ResourceLoaderModule expected.' );
 254                                 }
 255
 256                                 $this->moduleInfos[$name] = array( 'object' => $info );
 257                                 $info->setName( $name );
 258                                 $this->modules[$name] = $info;
 259                         } else {
 260                                 // New calling convention
 261                                 $this->moduleInfos[$name] = $info;
 262                         }
 263                 }
 264
 265                 wfProfileOut( __METHOD__ );
 266         }
 267
 268         /**
 269          */
 270         public function registerTestModules() {
 271                 global $IP, $wgEnableJavaScriptTest;
 272
 273                 if ( $wgEnableJavaScriptTest !== true ) {
 274                         throw new MWException( 'Attempt to register JavaScript test modules but <tt>$wgEnableJavaScriptTest</tt> is false. Edit your <tt>LocalSettings.php</tt> to enable it.' );
 275                 }
 276
 277                 wfProfileIn( __METHOD__ );
 278
 279                 // Get core test suites
 280                 $testModules = array();
 281                 $testModules['qunit'] = include( "$IP/tests/qunit/QUnitTestResources.php" );
 282                 // Get other test suites (e.g. from extensions)
 283                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 284
 285                 // Add the testrunner (which configures QUnit) to the dependencies.
 286                 // Since it must be ready before any of the test suites are executed.
 287                 foreach( $testModules['qunit'] as $moduleName => $moduleProps ) {
 288                         $testModules['qunit'][$moduleName]['dependencies'][] = 'mediawiki.tests.qunit.testrunner';
 289                 }
 290
 291                 foreach( $testModules as $id => $names ) {
 292                         // Register test modules
 293                         $this->register( $testModules[$id] );
 294
 295                         // Keep track of their names so that they can be loaded together
 296                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 297                 }
 298
 299                 wfProfileOut( __METHOD__ );
 300         }
 301
 302         /**
 303          * Add a foreign source of modules.
 304          *
 305          * Source properties:
 306          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 307          *
 308          * @param $id Mixed: source ID (string), or array( id1 => props1, id2 => props2, ... )
 309          * @param $properties Array: source properties
 310          */
 311         public function addSource( $id, $properties = null) {
 312                 // Allow multiple sources to be registered in one call
 313                 if ( is_array( $id ) ) {
 314                         foreach ( $id as $key => $value ) {
 315                                 $this->addSource( $key, $value );
 316                         }
 317                         return;
 318                 }
 319
 320                 // Disallow duplicates
 321                 if ( isset( $this->sources[$id] ) ) {
 322                         throw new MWException(
 323                                 'ResourceLoader duplicate source addition error. ' .
 324                                 'Another source has already been registered as ' . $id
 325                         );
 326                 }
 327
 328                 // Validate properties
 329                 foreach ( self::$requiredSourceProperties as $prop ) {
 330                         if ( !isset( $properties[$prop] ) ) {
 331                                 throw new MWException( "Required property $prop missing from source ID $id" );
 332                         }
 333                 }
 334
 335                 $this->sources[$id] = $properties;
 336         }
 337
 338         /**
 339          * Get a list of module names
 340          *
 341          * @return Array: List of module names
 342          */
 343         public function getModuleNames() {
 344                 return array_keys( $this->moduleInfos );
 345         }
 346
 347         /**
 348          * Get a list of test module names for one (or all) frameworks.
 349          * If the given framework id is unknkown, or if the in-object variable is not an array,
 350          * then it will return an empty array.
 351          *
 352          * @param $framework String: Optional. Get only the test module names for one
 353          * particular framework.
 354          * @return Array
 355          */
 356         public function getTestModuleNames( $framework = 'all' ) {
 357                 if ( $framework == 'all' ) {
 358                         return $this->testModuleNames;
 359                 } elseif ( isset( $this->testModuleNames[$framework] ) && is_array( $this->testModuleNames[$framework] ) ) {
 360                         return $this->testModuleNames[$framework];
 361                 } else {
 362                         return array();
 363                 }
 364         }
 365
 366         /**
 367          * Get the ResourceLoaderModule object for a given module name.
 368          *
 369          * @param $name String: Module name
 370          * @return ResourceLoaderModule if module has been registered, null otherwise
 371          */
 372         public function getModule( $name ) {
 373                 if ( !isset( $this->modules[$name] ) ) {
 374                         if ( !isset( $this->moduleInfos[$name] ) ) {
 375                                 // No such module
 376                                 return null;
 377                         }
 378                         // Construct the requested object
 379                         $info = $this->moduleInfos[$name];
 380                         if ( isset( $info['object'] ) ) {
 381                                 // Object given in info array
 382                                 $object = $info['object'];
 383                         } else {
 384                                 if ( !isset( $info['class'] ) ) {
 385                                         $class = 'ResourceLoaderFileModule';
 386                                 } else {
 387                                         $class = $info['class'];
 388                                 }
 389                                 $object = new $class( $info );
 390                         }
 391                         $object->setName( $name );
 392                         $this->modules[$name] = $object;
 393                 }
 394
 395                 return $this->modules[$name];
 396         }
 397
 398         /**
 399          * Get the list of sources
 400          *
 401          * @return Array: array( id => array of properties, .. )
 402          */
 403         public function getSources() {
 404                 return $this->sources;
 405         }
 406
 407         /**
 408          * Outputs a response to a resource load-request, including a content-type header.
 409          *
 410          * @param $context ResourceLoaderContext: Context in which a response should be formed
 411          */
 412         public function respond( ResourceLoaderContext $context ) {
 413                 global $wgCacheEpoch, $wgUseFileCache;
 414
 415                 // Use file cache if enabled and available...
 416                 if ( $wgUseFileCache ) {
 417                         $fileCache = ResourceFileCache::newFromContext( $context );
 418                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 419                                 return; // output handled
 420                         }
 421                 }
 422
 423                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 424                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 425                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 426                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 427                 // the whole thing in our own output buffer to be sure the active buffer
 428                 // doesn't use ob_gzhandler.
 429                 // See http://bugs.php.net/bug.php?id=36514
 430                 ob_start();
 431
 432                 wfProfileIn( __METHOD__ );
 433                 $exceptions = '';
 434
 435                 // Split requested modules into two groups, modules and missing
 436                 $modules = array();
 437                 $missing = array();
 438                 foreach ( $context->getModules() as $name ) {
 439                         if ( isset( $this->moduleInfos[$name] ) ) {
 440                                 $modules[$name] = $this->getModule( $name );
 441                         } else {
 442                                 $missing[] = $name;
 443                         }
 444                 }
 445
 446                 // Preload information needed to the mtime calculation below
 447                 try {
 448                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 449                 } catch( Exception $e ) {
 450                         // Add exception to the output as a comment
 451                         $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 452                 }
 453
 454                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 455
 456                 $private = false;
 457                 // To send Last-Modified and support If-Modified-Since, we need to detect
 458                 // the last modified time
 459                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 460                 foreach ( $modules as $module ) {
 461                         /**
 462                          * @var $module ResourceLoaderModule
 463                          */
 464                         try {
 465                                 // Bypass Squid and other shared caches if the request includes any private modules
 466                                 if ( $module->getGroup() === 'private' ) {
 467                                         $private = true;
 468                                 }
 469                                 // Calculate maximum modified time
 470                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 471                         } catch ( Exception $e ) {
 472                                 // Add exception to the output as a comment
 473                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 474                         }
 475                 }
 476
 477                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 478
 479                 // Send content type and cache related headers
 480                 $this->sendResponseHeaders( $context, $mtime, $private );
 481
 482                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 483                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 484                         wfProfileOut( __METHOD__ );
 485                         return; // output handled (buffers cleared)
 486                 }
 487
 488                 // Generate a response
 489                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 490
 491                 // Prepend comments indicating exceptions
 492                 $response = $exceptions . $response;
 493
 494                 // Capture any PHP warnings from the output buffer and append them to the
 495                 // response in a comment if we're in debug mode.
 496                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 497                         $response = "/*\n$warnings\n*/\n" . $response;
 498                 }
 499
 500                 // Remove the output buffer and output the response
 501                 ob_end_clean();
 502                 echo $response;
 503
 504                 // Save response to file cache unless there are private modules or errors
 505                 if ( isset( $fileCache ) && !$private && !$exceptions && !$missing ) {
 506                         // Cache single modules...and other requests if there are enough hits
 507                         if ( ResourceFileCache::useFileCache( $context ) ) {
 508                                 if ( $fileCache->isCacheWorthy() ) {
 509                                         $fileCache->saveText( $response );
 510                                 } else {
 511                                         $fileCache->incrMissesRecent( $context->getRequest() );
 512                                 }
 513                         }
 514                 }
 515
 516                 wfProfileOut( __METHOD__ );
 517         }
 518
 519         /**
 520          * Send content type and last modified headers to the client.
 521          * @param $context ResourceLoaderContext
 522          * @param $mtime string TS_MW timestamp to use for last-modified
 523          * @param $private bool True iff response contains any private modules
 524          * @return void
 525          */
 526         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $private ) {
 527                 global $wgResourceLoaderMaxage;
 528                 // If a version wasn't specified we need a shorter expiry time for updates
 529                 // to propagate to clients quickly
 530                 if ( is_null( $context->getVersion() ) ) {
 531                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 532                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 533                 // If a version was specified we can use a longer expiry time since changing
 534                 // version numbers causes cache misses
 535                 } else {
 536                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 537                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 538                 }
 539                 if ( $context->getOnly() === 'styles' ) {
 540                         header( 'Content-Type: text/css; charset=utf-8' );
 541                 } else {
 542                         header( 'Content-Type: text/javascript; charset=utf-8' );
 543                 }
 544                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 545                 if ( $context->getDebug() ) {
 546                         // Do not cache debug responses
 547                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 548                         header( 'Pragma: no-cache' );
 549                 } else {
 550                         if ( $private ) {
 551                                 header( "Cache-Control: private, max-age=$maxage" );
 552                                 $exp = $maxage;
 553                         } else {
 554                                 header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 555                                 $exp = min( $maxage, $smaxage );
 556                         }
 557                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 558                 }
 559         }
 560
 561         /**
 562          * If there's an If-Modified-Since header, respond with a 304 appropriately
 563          * and clear out the output buffer. If the client cache is too old then do nothing.
 564          * @param $context ResourceLoaderContext
 565          * @param $mtime string The TS_MW timestamp to check the header against
 566          * @return bool True iff 304 header sent and output handled
 567          */
 568         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 569                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 570                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 571                 // so we get a valid timestamp.
 572                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 573                 // Never send 304s in debug mode
 574                 if ( $ims !== false && !$context->getDebug() ) {
 575                         $imsTS = strtok( $ims, ';' );
 576                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 577                                 // There's another bug in ob_gzhandler (see also the comment at
 578                                 // the top of this function) that causes it to gzip even empty
 579                                 // responses, meaning it's impossible to produce a truly empty
 580                                 // response (because the gzip header is always there). This is
 581                                 // a problem because 304 responses have to be completely empty
 582                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 583                                 // See also http://bugs.php.net/bug.php?id=51579
 584                                 // To work around this, we tear down all output buffering before
 585                                 // sending the 304.
 586                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 587                                 // no matter how often we call ob_get_clean(), so instead of doing
 588                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 589                                 // we have to be safe here and avoid an infinite loop.
 590                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 591                                         ob_end_clean();
 592                                 }
 593
 594                                 header( 'HTTP/1.0 304 Not Modified' );
 595                                 header( 'Status: 304 Not Modified' );
 596                                 return true;
 597                         }
 598                 }
 599                 return false;
 600         }
 601
 602         /**
 603          * Send out code for a response from file cache if possible
 604          *
 605          * @param $fileCache ObjectFileCache: Cache object for this request URL
 606          * @param $context ResourceLoaderContext: Context in which to generate a response
 607          * @return bool If this found a cache file and handled the response
 608          */
 609         protected function tryRespondFromFileCache(
 610                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 611         ) {
 612                 global $wgResourceLoaderMaxage;
 613                 // Buffer output to catch warnings.
 614                 ob_start();
 615                 // Get the maximum age the cache can be
 616                 $maxage = is_null( $context->getVersion() )
 617                         ? $wgResourceLoaderMaxage['unversioned']['server']
 618                         : $wgResourceLoaderMaxage['versioned']['server'];
 619                 // Minimum timestamp the cache file must have
 620                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 621                 if ( !$good ) {
 622                         try { // RL always hits the DB on file cache miss...
 623                                 wfGetDB( DB_SLAVE );
 624                         } catch( DBConnectionError $e ) { // ...check if we need to fallback to cache
 625                                 $good = $fileCache->isCacheGood(); // cache existence check
 626                         }
 627                 }
 628                 if ( $good ) {
 629                         $ts = $fileCache->cacheTimestamp();
 630                         // Send content type and cache headers
 631                         $this->sendResponseHeaders( $context, $ts, false );
 632                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 633                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 634                                 return false; // output handled (buffers cleared)
 635                         }
 636                         $response = $fileCache->fetchText();
 637                         // Capture any PHP warnings from the output buffer and append them to the
 638                         // response in a comment if we're in debug mode.
 639                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 640                                 $response = "/*\n$warnings\n*/\n" . $response;
 641                         }
 642                         // Remove the output buffer and output the response
 643                         ob_end_clean();
 644                         echo $response . "\n/* Cached {$ts} */";
 645                         return true; // cache hit
 646                 }
 647                 // Clear buffer
 648                 ob_end_clean();
 649
 650                 return false; // cache miss
 651         }
 652
 653         /**
 654          * Generates code for a response
 655          *
 656          * @param $context ResourceLoaderContext: Context in which to generate a response
 657          * @param $modules Array: List of module objects keyed by module name
 658          * @param $missing Array: List of unavailable modules (optional)
 659          * @return String: Response data
 660          */
 661         public function makeModuleResponse( ResourceLoaderContext $context,
 662                 array $modules, $missing = array() )
 663         {
 664                 $out = '';
 665                 $exceptions = '';
 666                 if ( $modules === array() && $missing === array() ) {
 667                         return '/* No modules requested. Max made me put this here */';
 668                 }
 669
 670                 wfProfileIn( __METHOD__ );
 671                 // Pre-fetch blobs
 672                 if ( $context->shouldIncludeMessages() ) {
 673                         try {
 674                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 675                         } catch ( Exception $e ) {
 676                                 // Add exception to the output as a comment
 677                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 678                         }
 679                 } else {
 680                         $blobs = array();
 681                 }
 682
 683                 // Generate output
 684                 foreach ( $modules as $name => $module ) {
 685                         /**
 686                          * @var $module ResourceLoaderModule
 687                          */
 688
 689                         wfProfileIn( __METHOD__ . '-' . $name );
 690                         try {
 691                                 $scripts = '';
 692                                 if ( $context->shouldIncludeScripts() ) {
 693                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 694                                         // However, we can't do this if the module doesn't support it
 695                                         // We also can't do this if there is an only= parameter, because we have to give
 696                                         // the module a way to return a load.php URL without causing an infinite loop
 697                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 698                                                 $scripts = $module->getScriptURLsForDebug( $context );
 699                                         } else {
 700                                                 $scripts = $module->getScript( $context );
 701                                                 if ( is_string( $scripts ) ) {
 702                                                         // bug 27054: Append semicolon to prevent weird bugs
 703                                                         // caused by files not terminating their statements right
 704                                                         $scripts .= ";\n";
 705                                                 }
 706                                         }
 707                                 }
 708                                 // Styles
 709                                 $styles = array();
 710                                 if ( $context->shouldIncludeStyles() ) {
 711                                         // If we are in debug mode, we'll want to return an array of URLs
 712                                         // See comment near shouldIncludeScripts() for more details
 713                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 714                                                 $styles = $module->getStyleURLsForDebug( $context );
 715                                         } else {
 716                                                 $styles = $module->getStyles( $context );
 717                                         }
 718                                 }
 719
 720                                 // Messages
 721                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 722
 723                                 // Append output
 724                                 switch ( $context->getOnly() ) {
 725                                         case 'scripts':
 726                                                 if ( is_string( $scripts ) ) {
 727                                                         // Load scripts raw...
 728                                                         $out .= $scripts;
 729                                                 } elseif ( is_array( $scripts ) ) {
 730                                                         // ...except when $scripts is an array of URLs
 731                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 732                                                 }
 733                                                 break;
 734                                         case 'styles':
 735                                                 $out .= self::makeCombinedStyles( $styles );
 736                                                 break;
 737                                         case 'messages':
 738                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 739                                                 break;
 740                                         default:
 741                                                 // Minify CSS before embedding in mw.loader.implement call
 742                                                 // (unless in debug mode)
 743                                                 if ( !$context->getDebug() ) {
 744                                                         foreach ( $styles as $media => $style ) {
 745                                                                 if ( is_string( $style ) ) {
 746                                                                         $styles[$media] = $this->filter( 'minify-css', $style );
 747                                                                 }
 748                                                         }
 749                                                 }
 750                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 751                                                         new XmlJsCode( $messagesBlob ) );
 752                                                 break;
 753                                 }
 754                         } catch ( Exception $e ) {
 755                                 // Add exception to the output as a comment
 756                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 757
 758                                 // Register module as missing
 759                                 $missing[] = $name;
 760                                 unset( $modules[$name] );
 761                         }
 762                         wfProfileOut( __METHOD__ . '-' . $name );
 763                 }
 764
 765                 // Update module states
 766                 if ( $context->shouldIncludeScripts() ) {
 767                         // Set the state of modules loaded as only scripts to ready
 768                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 769                                 && !isset( $modules['startup'] ) )
 770                         {
 771                                 $out .= self::makeLoaderStateScript(
 772                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 773                         }
 774                         // Set the state of modules which were requested but unavailable as missing
 775                         if ( is_array( $missing ) && count( $missing ) ) {
 776                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 777                         }
 778                 }
 779
 780                 if ( !$context->getDebug() ) {
 781                         if ( $context->getOnly() === 'styles' ) {
 782                                 $out = $this->filter( 'minify-css', $out );
 783                         } else {
 784                                 $out = $this->filter( 'minify-js', $out );
 785                         }
 786                 }
 787
 788                 wfProfileOut( __METHOD__ );
 789                 return $exceptions . $out;
 790         }
 791
 792         /* Static Methods */
 793
 794         /**
 795          * Returns JS code to call to mw.loader.implement for a module with
 796          * given properties.
 797          *
 798          * @param $name string Module name
 799          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 800          * @param $styles Mixed: List of CSS strings keyed by media type, or list of lists of URLs to
 801          * CSS files keyed by media type
 802          * @param $messages Mixed: List of messages associated with this module. May either be an
 803          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 804          *     the same data, wrapped in an XmlJsCode object.
 805          *
 806          * @return string
 807          */
 808         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 809                 if ( is_string( $scripts ) ) {
 810                         $scripts = new XmlJsCode( "function( $ ) {{$scripts}}" );
 811                 } elseif ( !is_array( $scripts ) ) {
 812                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 813                 }
 814                 return Xml::encodeJsCall(
 815                         'mw.loader.implement',
 816                         array(
 817                                 $name,
 818                                 $scripts,
 819                                 (object)$styles,
 820                                 (object)$messages
 821                         ) );
 822         }
 823
 824         /**
 825          * Returns JS code which, when called, will register a given list of messages.
 826          *
 827          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 828          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 829          *
 830          * @return string
 831          */
 832         public static function makeMessageSetScript( $messages ) {
 833                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 834         }
 835
 836         /**
 837          * Combines an associative array mapping media type to CSS into a
 838          * single stylesheet with @media blocks.
 839          *
 840          * @param $styles Array: List of CSS strings keyed by media type
 841          *
 842          * @return string
 843          */
 844         public static function makeCombinedStyles( array $styles ) {
 845                 $out = '';
 846                 foreach ( $styles as $media => $style ) {
 847                         // Transform the media type based on request params and config
 848                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 849                         $media = OutputPage::transformCssMedia( $media );
 850
 851                         if ( $media === null ) {
 852                                 // Skip
 853                         } elseif ( $media === '' || $media == 'all' ) {
 854                                 // Don't output invalid or frivolous @media statements
 855                                 $out .= "$style\n";
 856                         } else {
 857                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 858                         }
 859                 }
 860                 return $out;
 861         }
 862
 863         /**
 864          * Returns a JS call to mw.loader.state, which sets the state of a
 865          * module or modules to a given value. Has two calling conventions:
 866          *
 867          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 868          *         Set the state of a single module called $name to $state
 869          *
 870          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 871          *         Set the state of modules with the given names to the given states
 872          *
 873          * @param $name string
 874          * @param $state
 875          *
 876          * @return string
 877          */
 878         public static function makeLoaderStateScript( $name, $state = null ) {
 879                 if ( is_array( $name ) ) {
 880                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 881                 } else {
 882                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 883                 }
 884         }
 885
 886         /**
 887          * Returns JS code which calls the script given by $script. The script will
 888          * be called with local variables name, version, dependencies and group,
 889          * which will have values corresponding to $name, $version, $dependencies
 890          * and $group as supplied.
 891          *
 892          * @param $name String: Module name
 893          * @param $version Integer: Module version number as a timestamp
 894          * @param $dependencies Array: List of module names on which this module depends
 895          * @param $group String: Group which the module is in.
 896          * @param $source String: Source of the module, or 'local' if not foreign.
 897          * @param $script String: JavaScript code
 898          *
 899          * @return string
 900          */
 901         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 902                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 903                 return Xml::encodeJsCall(
 904                         "( function( name, version, dependencies, group, source ) {\n\t$script\n} )",
 905                         array( $name, $version, $dependencies, $group, $source ) );
 906         }
 907
 908         /**
 909          * Returns JS code which calls mw.loader.register with the given
 910          * parameters. Has three calling conventions:
 911          *
 912          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 913          *       Register a single module.
 914          *
 915          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 916          *       Register modules with the given names.
 917          *
 918          *   - ResourceLoader::makeLoaderRegisterScript( array(
 919          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 920          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 921          *        ...
 922          *     ) ):
 923          *        Registers modules with the given names and parameters.
 924          *
 925          * @param $name String: Module name
 926          * @param $version Integer: Module version number as a timestamp
 927          * @param $dependencies Array: List of module names on which this module depends
 928          * @param $group String: group which the module is in.
 929          * @param $source String: source of the module, or 'local' if not foreign
 930          *
 931          * @return string
 932          */
 933         public static function makeLoaderRegisterScript( $name, $version = null,
 934                 $dependencies = null, $group = null, $source = null )
 935         {
 936                 if ( is_array( $name ) ) {
 937                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 938                 } else {
 939                         $version = (int) $version > 1 ? (int) $version : 1;
 940                         return Xml::encodeJsCall( 'mw.loader.register',
 941                                 array( $name, $version, $dependencies, $group, $source ) );
 942                 }
 943         }
 944
 945         /**
 946          * Returns JS code which calls mw.loader.addSource() with the given
 947          * parameters. Has two calling conventions:
 948          *
 949          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
 950          *       Register a single source
 951          *
 952          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
 953          *       Register sources with the given IDs and properties.
 954          *
 955          * @param $id String: source ID
 956          * @param $properties Array: source properties (see addSource())
 957          *
 958          * @return string
 959          */
 960         public static function makeLoaderSourcesScript( $id, $properties = null ) {
 961                 if ( is_array( $id ) ) {
 962                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
 963                 } else {
 964                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
 965                 }
 966         }
 967
 968         /**
 969          * Returns JS code which runs given JS code if the client-side framework is
 970          * present.
 971          *
 972          * @param $script String: JavaScript code
 973          *
 974          * @return string
 975          */
 976         public static function makeLoaderConditionalScript( $script ) {
 977                 return "if(window.mw){\n".trim( $script )."\n}";
 978         }
 979
 980         /**
 981          * Returns JS code which will set the MediaWiki configuration array to
 982          * the given value.
 983          *
 984          * @param $configuration Array: List of configuration values keyed by variable name
 985          *
 986          * @return string
 987          */
 988         public static function makeConfigSetScript( array $configuration ) {
 989                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
 990         }
 991
 992         /**
 993          * Convert an array of module names to a packed query string.
 994          *
 995          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
 996          * becomes 'foo.bar,baz|bar.baz,quux'
 997          * @param $modules array of module names (strings)
 998          * @return string Packed query string
 999          */
1000         public static function makePackedModulesString( $modules ) {
1001                 $groups = array(); // array( prefix => array( suffixes ) )
1002                 foreach ( $modules as $module ) {
1003                         $pos = strrpos( $module, '.' );
1004                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1005                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1006                         $groups[$prefix][] = $suffix;
1007                 }
1008
1009                 $arr = array();
1010                 foreach ( $groups as $prefix => $suffixes ) {
1011                         $p = $prefix === '' ? '' : $prefix . '.';
1012                         $arr[] = $p . implode( ',', $suffixes );
1013                 }
1014                 $str = implode( '|', $arr );
1015                 return $str;
1016         }
1017
1018         /**
1019          * Determine whether debug mode was requested
1020          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1021          * @return bool
1022          */
1023         public static function inDebugMode() {
1024                 global $wgRequest, $wgResourceLoaderDebug;
1025                 static $retval = null;
1026                 if ( !is_null( $retval ) ) {
1027                         return $retval;
1028                 }
1029                 return $retval = $wgRequest->getFuzzyBool( 'debug',
1030                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
1031         }
1032
1033         /**
1034          * Build a load.php URL
1035          * @param $modules array of module names (strings)
1036          * @param $lang string Language code
1037          * @param $skin string Skin name
1038          * @param $user string|null User name. If null, the &user= parameter is omitted
1039          * @param $version string|null Versioning timestamp
1040          * @param $debug bool Whether the request should be in debug mode
1041          * @param $only string|null &only= parameter
1042          * @param $printable bool Printable mode
1043          * @param $handheld bool Handheld mode
1044          * @param $extraQuery array Extra query parameters to add
1045          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1046          */
1047         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1048                         $printable = false, $handheld = false, $extraQuery = array() ) {
1049                 global $wgLoadScript;
1050                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1051                         $only, $printable, $handheld, $extraQuery
1052                 );
1053
1054                 // Prevent the IE6 extension check from being triggered (bug 28840)
1055                 // by appending a character that's invalid in Windows extensions ('*')
1056                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1057         }
1058
1059         /**
1060          * Build a query array (array representation of query string) for load.php. Helper
1061          * function for makeLoaderURL().
1062          * @return array
1063          */
1064         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1065                         $printable = false, $handheld = false, $extraQuery = array() ) {
1066                 $query = array(
1067                         'modules' => self::makePackedModulesString( $modules ),
1068                         'lang' => $lang,
1069                         'skin' => $skin,
1070                         'debug' => $debug ? 'true' : 'false',
1071                 );
1072                 if ( $user !== null ) {
1073                         $query['user'] = $user;
1074                 }
1075                 if ( $version !== null ) {
1076                         $query['version'] = $version;
1077                 }
1078                 if ( $only !== null ) {
1079                         $query['only'] = $only;
1080                 }
1081                 if ( $printable ) {
1082                         $query['printable'] = 1;
1083                 }
1084                 if ( $handheld ) {
1085                         $query['handheld'] = 1;
1086                 }
1087                 $query += $extraQuery;
1088
1089                 // Make queries uniform in order
1090                 ksort( $query );
1091                 return $query;
1092         }
1093 }