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