includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 use Composer\Semver\Semver;
   4 use Wikimedia\ScopedCallback;
   5 use MediaWiki\Shell\Shell;
   6 use MediaWiki\ShellDisabledError;
   7
   8 /**
   9  * ExtensionRegistry class
  10  *
  11  * The Registry loads JSON files, and uses a Processor
  12  * to extract information from them. It also registers
  13  * classes with the autoloader.
  14  *
  15  * @since 1.25
  16  */
  17 class ExtensionRegistry {
  18
  19         /**
  20          * "requires" key that applies to MediaWiki core/$wgVersion
  21          */
  22         const MEDIAWIKI_CORE = 'MediaWiki';
  23
  24         /**
  25          * Version of the highest supported manifest version
  26          * Note: Update MANIFEST_VERSION_MW_VERSION when changing this
  27          */
  28         const MANIFEST_VERSION = 2;
  29
  30         /**
  31          * MediaWiki version constraint representing what the current
  32          * highest MANIFEST_VERSION is supported in
  33          */
  34         const MANIFEST_VERSION_MW_VERSION = '>= 1.29.0';
  35
  36         /**
  37          * Version of the oldest supported manifest version
  38          */
  39         const OLDEST_MANIFEST_VERSION = 1;
  40
  41         /**
  42          * Bump whenever the registration cache needs resetting
  43          */
  44         const CACHE_VERSION = 7;
  45
  46         /**
  47          * Special key that defines the merge strategy
  48          *
  49          * @since 1.26
  50          */
  51         const MERGE_STRATEGY = '_merge_strategy';
  52
  53         /**
  54          * Array of loaded things, keyed by name, values are credits information
  55          *
  56          * @var array
  57          */
  58         private $loaded = [];
  59
  60         /**
  61          * List of paths that should be loaded
  62          *
  63          * @var array
  64          */
  65         protected $queued = [];
  66
  67         /**
  68          * Whether we are done loading things
  69          *
  70          * @var bool
  71          */
  72         private $finished = false;
  73
  74         /**
  75          * Items in the JSON file that aren't being
  76          * set as globals
  77          *
  78          * @var array
  79          */
  80         protected $attributes = [];
  81
  82         /**
  83          * Attributes for testing
  84          *
  85          * @var array
  86          */
  87         protected $testAttributes = [];
  88
  89         /**
  90          * @var ExtensionRegistry
  91          */
  92         private static $instance;
  93
  94         /**
  95          * @codeCoverageIgnore
  96          * @return ExtensionRegistry
  97          */
  98         public static function getInstance() {
  99                 if ( self::$instance === null ) {
 100                         self::$instance = new self();
 101                 }
 102
 103                 return self::$instance;
 104         }
 105
 106         /**
 107          * @param string $path Absolute path to the JSON file
 108          */
 109         public function queue( $path ) {
 110                 global $wgExtensionInfoMTime;
 111
 112                 $mtime = $wgExtensionInfoMTime;
 113                 if ( $mtime === false ) {
 114                         if ( file_exists( $path ) ) {
 115                                 $mtime = filemtime( $path );
 116                         } else {
 117                                 throw new Exception( "$path does not exist!" );
 118                         }
 119                         // @codeCoverageIgnoreStart
 120                         if ( $mtime === false ) {
 121                                 $err = error_get_last();
 122                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
 123                                 // @codeCoverageIgnoreEnd
 124                         }
 125                 }
 126                 $this->queued[$path] = $mtime;
 127         }
 128
 129         /**
 130          * @throws MWException If the queue is already marked as finished (no further things should
 131          *  be loaded then).
 132          */
 133         public function loadFromQueue() {
 134                 global $wgVersion, $wgDevelopmentWarnings;
 135                 if ( !$this->queued ) {
 136                         return;
 137                 }
 138
 139                 if ( $this->finished ) {
 140                         throw new MWException(
 141                                 "The following paths tried to load late: "
 142                                 . implode( ', ', array_keys( $this->queued ) )
 143                         );
 144                 }
 145
 146                 // A few more things to vary the cache on
 147                 $versions = [
 148                         'registration' => self::CACHE_VERSION,
 149                         'mediawiki' => $wgVersion,
 150                         'abilities' => $this->getAbilities(),
 151                 ];
 152
 153                 // We use a try/catch because we don't want to fail here
 154                 // if $wgObjectCaches is not configured properly for APC setup
 155                 try {
 156                         // Don't use MediaWikiServices here to prevent instantiating it before extensions have
 157                         // been loaded
 158                         $cacheId = ObjectCache::detectLocalServerCache();
 159                         $cache = ObjectCache::newFromId( $cacheId );
 160                 } catch ( InvalidArgumentException $e ) {
 161                         $cache = new EmptyBagOStuff();
 162                 }
 163                 // See if this queue is in APC
 164                 $key = $cache->makeKey(
 165                         'registration',
 166                         md5( json_encode( $this->queued + $versions ) )
 167                 );
 168                 $data = $cache->get( $key );
 169                 if ( $data ) {
 170                         $this->exportExtractedData( $data );
 171                 } else {
 172                         $data = $this->readFromQueue( $this->queued );
 173                         $this->exportExtractedData( $data );
 174                         // Do this late since we don't want to extract it since we already
 175                         // did that, but it should be cached
 176                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 177                         unset( $data['autoload'] );
 178                         if ( !( $data['warnings'] && $wgDevelopmentWarnings ) ) {
 179                                 // If there were no warnings that were shown, cache it
 180                                 $cache->set( $key, $data, 60 * 60 * 24 );
 181                         }
 182                 }
 183                 $this->queued = [];
 184         }
 185
 186         /**
 187          * Get the current load queue. Not intended to be used
 188          * outside of the installer.
 189          *
 190          * @return array
 191          */
 192         public function getQueue() {
 193                 return $this->queued;
 194         }
 195
 196         /**
 197          * Clear the current load queue. Not intended to be used
 198          * outside of the installer.
 199          */
 200         public function clearQueue() {
 201                 $this->queued = [];
 202         }
 203
 204         /**
 205          * After this is called, no more extensions can be loaded
 206          *
 207          * @since 1.29
 208          */
 209         public function finish() {
 210                 $this->finished = true;
 211         }
 212
 213         /**
 214          * Get the list of abilities and their values
 215          * @return bool[]
 216          */
 217         private function getAbilities() {
 218                 return [
 219                         'shell' => !Shell::isDisabled(),
 220                 ];
 221         }
 222
 223         /**
 224          * Queries information about the software environment and constructs an appropiate version checker
 225          *
 226          * @return VersionChecker
 227          */
 228         private function buildVersionChecker() {
 229                 global $wgVersion;
 230                 // array to optionally specify more verbose error messages for
 231                 // missing abilities
 232                 $abilityErrors = [
 233                         'shell' => ( new ShellDisabledError() )->getMessage(),
 234                 ];
 235
 236                 return new VersionChecker(
 237                         $wgVersion,
 238                         PHP_MAJOR_VERSION . '.' . PHP_MINOR_VERSION . '.' . PHP_RELEASE_VERSION,
 239                         get_loaded_extensions(),
 240                         $this->getAbilities(),
 241                         $abilityErrors
 242                 );
 243         }
 244
 245         /**
 246          * Process a queue of extensions and return their extracted data
 247          *
 248          * @param array $queue keys are filenames, values are ignored
 249          * @return array extracted info
 250          * @throws Exception
 251          * @throws ExtensionDependencyError
 252          */
 253         public function readFromQueue( array $queue ) {
 254                 $autoloadClasses = [];
 255                 $autoloadNamespaces = [];
 256                 $autoloaderPaths = [];
 257                 $processor = new ExtensionProcessor();
 258                 $versionChecker = $this->buildVersionChecker();
 259                 $extDependencies = [];
 260                 $incompatible = [];
 261                 $warnings = false;
 262                 foreach ( $queue as $path => $mtime ) {
 263                         $json = file_get_contents( $path );
 264                         if ( $json === false ) {
 265                                 throw new Exception( "Unable to read $path, does it exist?" );
 266                         }
 267                         $info = json_decode( $json, /* $assoc = */ true );
 268                         if ( !is_array( $info ) ) {
 269                                 throw new Exception( "$path is not a valid JSON file." );
 270                         }
 271
 272                         if ( !isset( $info['manifest_version'] ) ) {
 273                                 wfDeprecated(
 274                                         "{$info['name']}'s extension.json or skin.json does not have manifest_version",
 275                                         '1.29'
 276                                 );
 277                                 $warnings = true;
 278                                 // For backwards-compatability, assume a version of 1
 279                                 $info['manifest_version'] = 1;
 280                         }
 281                         $version = $info['manifest_version'];
 282                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 283                                 $incompatible[] = "$path: unsupported manifest_version: {$version}";
 284                         }
 285
 286                         $dir = dirname( $path );
 287                         if ( isset( $info['AutoloadClasses'] ) ) {
 288                                 $autoload = $this->processAutoLoader( $dir, $info['AutoloadClasses'] );
 289                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 290                                 $autoloadClasses += $autoload;
 291                         }
 292                         if ( isset( $info['AutoloadNamespaces'] ) ) {
 293                                 $autoloadNamespaces += $this->processAutoLoader( $dir, $info['AutoloadNamespaces'] );
 294                                 AutoLoader::$psr4Namespaces += $autoloadNamespaces;
 295                         }
 296
 297                         // get all requirements/dependencies for this extension
 298                         $requires = $processor->getRequirements( $info );
 299
 300                         // validate the information needed and add the requirements
 301                         if ( is_array( $requires ) && $requires && isset( $info['name'] ) ) {
 302                                 $extDependencies[$info['name']] = $requires;
 303                         }
 304
 305                         // Get extra paths for later inclusion
 306                         $autoloaderPaths = array_merge( $autoloaderPaths,
 307                                 $processor->getExtraAutoloaderPaths( $dir, $info ) );
 308                         // Compatible, read and extract info
 309                         $processor->extractInfo( $path, $info, $version );
 310                 }
 311                 $data = $processor->getExtractedInfo();
 312                 $data['warnings'] = $warnings;
 313
 314                 // check for incompatible extensions
 315                 $incompatible = array_merge(
 316                         $incompatible,
 317                         $versionChecker
 318                                 ->setLoadedExtensionsAndSkins( $data['credits'] )
 319                                 ->checkArray( $extDependencies )
 320                 );
 321
 322                 if ( $incompatible ) {
 323                         throw new ExtensionDependencyError( $incompatible );
 324                 }
 325
 326                 // Need to set this so we can += to it later
 327                 $data['globals']['wgAutoloadClasses'] = [];
 328                 $data['autoload'] = $autoloadClasses;
 329                 $data['autoloaderPaths'] = $autoloaderPaths;
 330                 $data['autoloaderNS'] = $autoloadNamespaces;
 331                 return $data;
 332         }
 333
 334         protected function exportExtractedData( array $info ) {
 335                 foreach ( $info['globals'] as $key => $val ) {
 336                         // If a merge strategy is set, read it and remove it from the value
 337                         // so it doesn't accidentally end up getting set.
 338                         if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
 339                                 $mergeStrategy = $val[self::MERGE_STRATEGY];
 340                                 unset( $val[self::MERGE_STRATEGY] );
 341                         } else {
 342                                 $mergeStrategy = 'array_merge';
 343                         }
 344
 345                         // Optimistic: If the global is not set, or is an empty array, replace it entirely.
 346                         // Will be O(1) performance.
 347                         if ( !array_key_exists( $key, $GLOBALS ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 348                                 $GLOBALS[$key] = $val;
 349                                 continue;
 350                         }
 351
 352                         if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
 353                                 // config setting that has already been overridden, don't set it
 354                                 continue;
 355                         }
 356
 357                         switch ( $mergeStrategy ) {
 358                                 case 'array_merge_recursive':
 359                                         $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 360                                         break;
 361                                 case 'array_replace_recursive':
 362                                         $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
 363                                         break;
 364                                 case 'array_plus_2d':
 365                                         $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
 366                                         break;
 367                                 case 'array_plus':
 368                                         $GLOBALS[$key] += $val;
 369                                         break;
 370                                 case 'array_merge':
 371                                         $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 372                                         break;
 373                                 default:
 374                                         throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
 375                         }
 376                 }
 377
 378                 if ( isset( $info['autoloaderNS'] ) ) {
 379                         AutoLoader::$psr4Namespaces += $info['autoloaderNS'];
 380                 }
 381
 382                 foreach ( $info['defines'] as $name => $val ) {
 383                         define( $name, $val );
 384                 }
 385                 foreach ( $info['autoloaderPaths'] as $path ) {
 386                         if ( file_exists( $path ) ) {
 387                                 require_once $path;
 388                         }
 389                 }
 390
 391                 $this->loaded += $info['credits'];
 392                 if ( $info['attributes'] ) {
 393                         if ( !$this->attributes ) {
 394                                 $this->attributes = $info['attributes'];
 395                         } else {
 396                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 397                         }
 398                 }
 399
 400                 foreach ( $info['callbacks'] as $name => $cb ) {
 401                         if ( !is_callable( $cb ) ) {
 402                                 if ( is_array( $cb ) ) {
 403                                         $cb = '[ ' . implode( ', ', $cb ) . ' ]';
 404                                 }
 405                                 throw new UnexpectedValueException( "callback '$cb' is not callable" );
 406                         }
 407                         $cb( $info['credits'][$name] );
 408                 }
 409         }
 410
 411         /**
 412          * Loads and processes the given JSON file without delay
 413          *
 414          * If some extensions are already queued, this will load
 415          * those as well.
 416          *
 417          * @param string $path Absolute path to the JSON file
 418          */
 419         public function load( $path ) {
 420                 $this->loadFromQueue(); // First clear the queue
 421                 $this->queue( $path );
 422                 $this->loadFromQueue();
 423         }
 424
 425         /**
 426          * Whether a thing has been loaded
 427          * @param string $name
 428          * @param string $constraint The required version constraint for this dependency
 429          * @throws LogicException if a specific contraint is asked for,
 430          *                        but the extension isn't versioned
 431          * @return bool
 432          */
 433         public function isLoaded( $name, $constraint = '*' ) {
 434                 $isLoaded = isset( $this->loaded[$name] );
 435                 if ( $constraint === '*' || !$isLoaded ) {
 436                         return $isLoaded;
 437                 }
 438                 // if a specific constraint is requested, but no version is set, throw an exception
 439                 if ( !isset( $this->loaded[$name]['version'] ) ) {
 440                         $msg = "{$name} does not expose its version, but an extension or a skin"
 441                                         . " requires: {$constraint}.";
 442                         throw new LogicException( $msg );
 443                 }
 444
 445                 return SemVer::satisfies( $this->loaded[$name]['version'], $constraint );
 446         }
 447
 448         /**
 449          * @param string $name
 450          * @return array
 451          */
 452         public function getAttribute( $name ) {
 453                 return $this->testAttributes[$name] ??
 454                         $this->attributes[$name] ?? [];
 455         }
 456
 457         /**
 458          * Force override the value of an attribute during tests
 459          *
 460          * @param string $name Name of attribute to override
 461          * @param array $value Value to set
 462          * @return ScopedCallback to reset
 463          * @since 1.33
 464          */
 465         public function setAttributeForTest( $name, array $value ) {
 466                 // @codeCoverageIgnoreStart
 467                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 468                         throw new RuntimeException( __METHOD__ . ' can only be used in tests' );
 469                 }
 470                 // @codeCoverageIgnoreEnd
 471                 if ( isset( $this->testAttributes[$name] ) ) {
 472                         throw new Exception( "The attribute '$name' has already been overridden" );
 473                 }
 474                 $this->testAttributes[$name] = $value;
 475                 return new ScopedCallback( function () use ( $name ) {
 476                         unset( $this->testAttributes[$name] );
 477                 } );
 478         }
 479
 480         /**
 481          * Get information about all things
 482          *
 483          * @return array
 484          */
 485         public function getAllThings() {
 486                 return $this->loaded;
 487         }
 488
 489         /**
 490          * Fully expand autoloader paths
 491          *
 492          * @param string $dir
 493          * @param array $files
 494          * @return array
 495          */
 496         protected function processAutoLoader( $dir, array $files ) {
 497                 // Make paths absolute, relative to the JSON file
 498                 foreach ( $files as &$file ) {
 499                         $file = "$dir/$file";
 500                 }
 501                 return $files;
 502         }
 503 }