includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 use MediaWiki\MediaWikiServices;
   4
   5 /**
   6  * ExtensionRegistry class
   7  *
   8  * The Registry loads JSON files, and uses a Processor
   9  * to extract information from them. It also registers
  10  * classes with the autoloader.
  11  *
  12  * @since 1.25
  13  */
  14 class ExtensionRegistry {
  15
  16         /**
  17          * "requires" key that applies to MediaWiki core/$wgVersion
  18          */
  19         const MEDIAWIKI_CORE = 'MediaWiki';
  20
  21         /**
  22          * Version of the highest supported manifest version
  23          * Note: Update MANIFEST_VERSION_MW_VERSION when changing this
  24          */
  25         const MANIFEST_VERSION = 2;
  26
  27         /**
  28          * MediaWiki version constraint representing what the current
  29          * highest MANIFEST_VERSION is supported in
  30          */
  31         const MANIFEST_VERSION_MW_VERSION = '>= 1.29.0';
  32
  33         /**
  34          * Version of the oldest supported manifest version
  35          */
  36         const OLDEST_MANIFEST_VERSION = 1;
  37
  38         /**
  39          * Bump whenever the registration cache needs resetting
  40          */
  41         const CACHE_VERSION = 6;
  42
  43         /**
  44          * Special key that defines the merge strategy
  45          *
  46          * @since 1.26
  47          */
  48         const MERGE_STRATEGY = '_merge_strategy';
  49
  50         /**
  51          * Array of loaded things, keyed by name, values are credits information
  52          *
  53          * @var array
  54          */
  55         private $loaded = [];
  56
  57         /**
  58          * List of paths that should be loaded
  59          *
  60          * @var array
  61          */
  62         protected $queued = [];
  63
  64         /**
  65          * Whether we are done loading things
  66          *
  67          * @var bool
  68          */
  69         private $finished = false;
  70
  71         /**
  72          * Items in the JSON file that aren't being
  73          * set as globals
  74          *
  75          * @var array
  76          */
  77         protected $attributes = [];
  78
  79         /**
  80          * @var ExtensionRegistry
  81          */
  82         private static $instance;
  83
  84         /**
  85          * @codeCoverageIgnore
  86          * @return ExtensionRegistry
  87          */
  88         public static function getInstance() {
  89                 if ( self::$instance === null ) {
  90                         self::$instance = new self();
  91                 }
  92
  93                 return self::$instance;
  94         }
  95
  96         /**
  97          * @param string $path Absolute path to the JSON file
  98          */
  99         public function queue( $path ) {
 100                 global $wgExtensionInfoMTime;
 101
 102                 $mtime = $wgExtensionInfoMTime;
 103                 if ( $mtime === false ) {
 104                         if ( file_exists( $path ) ) {
 105                                 $mtime = filemtime( $path );
 106                         } else {
 107                                 throw new Exception( "$path does not exist!" );
 108                         }
 109                         // @codeCoverageIgnoreStart
 110                         if ( !$mtime ) {
 111                                 $err = error_get_last();
 112                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
 113                                 // @codeCoverageIgnoreEnd
 114                         }
 115                 }
 116                 $this->queued[$path] = $mtime;
 117         }
 118
 119         /**
 120          * @throws MWException If the queue is already marked as finished (no further things should
 121          *  be loaded then).
 122          */
 123         public function loadFromQueue() {
 124                 global $wgVersion, $wgDevelopmentWarnings;
 125                 if ( !$this->queued ) {
 126                         return;
 127                 }
 128
 129                 if ( $this->finished ) {
 130                         throw new MWException(
 131                                 "The following paths tried to load late: "
 132                                 . implode( ', ', array_keys( $this->queued ) )
 133                         );
 134                 }
 135
 136                 // A few more things to vary the cache on
 137                 $versions = [
 138                         'registration' => self::CACHE_VERSION,
 139                         'mediawiki' => $wgVersion
 140                 ];
 141
 142                 // We use a try/catch because we don't want to fail here
 143                 // if $wgObjectCaches is not configured properly for APC setup
 144                 try {
 145                         $cache = MediaWikiServices::getInstance()->getLocalServerObjectCache();
 146                 } catch ( MWException $e ) {
 147                         $cache = new EmptyBagOStuff();
 148                 }
 149                 // See if this queue is in APC
 150                 $key = $cache->makeKey(
 151                         'registration',
 152                         md5( json_encode( $this->queued + $versions ) )
 153                 );
 154                 $data = $cache->get( $key );
 155                 if ( $data ) {
 156                         $this->exportExtractedData( $data );
 157                 } else {
 158                         $data = $this->readFromQueue( $this->queued );
 159                         $this->exportExtractedData( $data );
 160                         // Do this late since we don't want to extract it since we already
 161                         // did that, but it should be cached
 162                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 163                         unset( $data['autoload'] );
 164                         if ( !( $data['warnings'] && $wgDevelopmentWarnings ) ) {
 165                                 // If there were no warnings that were shown, cache it
 166                                 $cache->set( $key, $data, 60 * 60 * 24 );
 167                         }
 168                 }
 169                 $this->queued = [];
 170         }
 171
 172         /**
 173          * Get the current load queue. Not intended to be used
 174          * outside of the installer.
 175          *
 176          * @return array
 177          */
 178         public function getQueue() {
 179                 return $this->queued;
 180         }
 181
 182         /**
 183          * Clear the current load queue. Not intended to be used
 184          * outside of the installer.
 185          */
 186         public function clearQueue() {
 187                 $this->queued = [];
 188         }
 189
 190         /**
 191          * After this is called, no more extensions can be loaded
 192          *
 193          * @since 1.29
 194          */
 195         public function finish() {
 196                 $this->finished = true;
 197         }
 198
 199         /**
 200          * Process a queue of extensions and return their extracted data
 201          *
 202          * @param array $queue keys are filenames, values are ignored
 203          * @return array extracted info
 204          * @throws Exception
 205          */
 206         public function readFromQueue( array $queue ) {
 207                 global $wgVersion;
 208                 $autoloadClasses = [];
 209                 $autoloadNamespaces = [];
 210                 $autoloaderPaths = [];
 211                 $processor = new ExtensionProcessor();
 212                 $versionChecker = new VersionChecker( $wgVersion );
 213                 $extDependencies = [];
 214                 $incompatible = [];
 215                 $warnings = false;
 216                 foreach ( $queue as $path => $mtime ) {
 217                         $json = file_get_contents( $path );
 218                         if ( $json === false ) {
 219                                 throw new Exception( "Unable to read $path, does it exist?" );
 220                         }
 221                         $info = json_decode( $json, /* $assoc = */ true );
 222                         if ( !is_array( $info ) ) {
 223                                 throw new Exception( "$path is not a valid JSON file." );
 224                         }
 225
 226                         if ( !isset( $info['manifest_version'] ) ) {
 227                                 wfDeprecated(
 228                                         "{$info['name']}'s extension.json or skin.json does not have manifest_version",
 229                                         '1.29'
 230                                 );
 231                                 $warnings = true;
 232                                 // For backwards-compatability, assume a version of 1
 233                                 $info['manifest_version'] = 1;
 234                         }
 235                         $version = $info['manifest_version'];
 236                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 237                                 $incompatible[] = "$path: unsupported manifest_version: {$version}";
 238                         }
 239
 240                         $dir = dirname( $path );
 241                         if ( isset( $info['AutoloadClasses'] ) ) {
 242                                 $autoload = $this->processAutoLoader( $dir, $info['AutoloadClasses'] );
 243                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 244                                 $autoloadClasses += $autoload;
 245                         }
 246                         if ( isset( $info['AutoloadNamespaces'] ) ) {
 247                                 $autoloadNamespaces += $this->processAutoLoader( $dir, $info['AutoloadNamespaces'] );
 248                         }
 249
 250                         // get all requirements/dependencies for this extension
 251                         $requires = $processor->getRequirements( $info );
 252
 253                         // validate the information needed and add the requirements
 254                         if ( is_array( $requires ) && $requires && isset( $info['name'] ) ) {
 255                                 $extDependencies[$info['name']] = $requires;
 256                         }
 257
 258                         // Get extra paths for later inclusion
 259                         $autoloaderPaths = array_merge( $autoloaderPaths,
 260                                 $processor->getExtraAutoloaderPaths( $dir, $info ) );
 261                         // Compatible, read and extract info
 262                         $processor->extractInfo( $path, $info, $version );
 263                 }
 264                 $data = $processor->getExtractedInfo();
 265                 $data['warnings'] = $warnings;
 266
 267                 // check for incompatible extensions
 268                 $incompatible = array_merge(
 269                         $incompatible,
 270                         $versionChecker
 271                                 ->setLoadedExtensionsAndSkins( $data['credits'] )
 272                                 ->checkArray( $extDependencies )
 273                 );
 274
 275                 if ( $incompatible ) {
 276                         if ( count( $incompatible ) === 1 ) {
 277                                 throw new Exception( $incompatible[0] );
 278                         } else {
 279                                 throw new Exception( implode( "\n", $incompatible ) );
 280                         }
 281                 }
 282
 283                 // Need to set this so we can += to it later
 284                 $data['globals']['wgAutoloadClasses'] = [];
 285                 $data['autoload'] = $autoloadClasses;
 286                 $data['autoloaderPaths'] = $autoloaderPaths;
 287                 $data['autoloaderNS'] = $autoloadNamespaces;
 288                 return $data;
 289         }
 290
 291         protected function exportExtractedData( array $info ) {
 292                 foreach ( $info['globals'] as $key => $val ) {
 293                         // If a merge strategy is set, read it and remove it from the value
 294                         // so it doesn't accidentally end up getting set.
 295                         if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
 296                                 $mergeStrategy = $val[self::MERGE_STRATEGY];
 297                                 unset( $val[self::MERGE_STRATEGY] );
 298                         } else {
 299                                 $mergeStrategy = 'array_merge';
 300                         }
 301
 302                         // Optimistic: If the global is not set, or is an empty array, replace it entirely.
 303                         // Will be O(1) performance.
 304                         if ( !array_key_exists( $key, $GLOBALS ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 305                                 $GLOBALS[$key] = $val;
 306                                 continue;
 307                         }
 308
 309                         if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
 310                                 // config setting that has already been overridden, don't set it
 311                                 continue;
 312                         }
 313
 314                         switch ( $mergeStrategy ) {
 315                                 case 'array_merge_recursive':
 316                                         $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 317                                         break;
 318                                 case 'array_replace_recursive':
 319                                         $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
 320                                         break;
 321                                 case 'array_plus_2d':
 322                                         $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
 323                                         break;
 324                                 case 'array_plus':
 325                                         $GLOBALS[$key] += $val;
 326                                         break;
 327                                 case 'array_merge':
 328                                         $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 329                                         break;
 330                                 default:
 331                                         throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
 332                         }
 333                 }
 334
 335                 if ( isset( $info['autoloaderNS'] ) ) {
 336                         AutoLoader::$psr4Namespaces += $info['autoloaderNS'];
 337                 }
 338
 339                 foreach ( $info['defines'] as $name => $val ) {
 340                         define( $name, $val );
 341                 }
 342                 foreach ( $info['autoloaderPaths'] as $path ) {
 343                         if ( file_exists( $path ) ) {
 344                                 require_once $path;
 345                         }
 346                 }
 347
 348                 $this->loaded += $info['credits'];
 349                 if ( $info['attributes'] ) {
 350                         if ( !$this->attributes ) {
 351                                 $this->attributes = $info['attributes'];
 352                         } else {
 353                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 354                         }
 355                 }
 356
 357                 foreach ( $info['callbacks'] as $name => $cb ) {
 358                         if ( !is_callable( $cb ) ) {
 359                                 if ( is_array( $cb ) ) {
 360                                         $cb = '[ ' . implode( ', ', $cb ) . ' ]';
 361                                 }
 362                                 throw new UnexpectedValueException( "callback '$cb' is not callable" );
 363                         }
 364                         call_user_func( $cb, $info['credits'][$name] );
 365                 }
 366         }
 367
 368         /**
 369          * Loads and processes the given JSON file without delay
 370          *
 371          * If some extensions are already queued, this will load
 372          * those as well.
 373          *
 374          * @param string $path Absolute path to the JSON file
 375          */
 376         public function load( $path ) {
 377                 $this->loadFromQueue(); // First clear the queue
 378                 $this->queue( $path );
 379                 $this->loadFromQueue();
 380         }
 381
 382         /**
 383          * Whether a thing has been loaded
 384          * @param string $name
 385          * @return bool
 386          */
 387         public function isLoaded( $name ) {
 388                 return isset( $this->loaded[$name] );
 389         }
 390
 391         /**
 392          * @param string $name
 393          * @return array
 394          */
 395         public function getAttribute( $name ) {
 396                 if ( isset( $this->attributes[$name] ) ) {
 397                         return $this->attributes[$name];
 398                 } else {
 399                         return [];
 400                 }
 401         }
 402
 403         /**
 404          * Get information about all things
 405          *
 406          * @return array
 407          */
 408         public function getAllThings() {
 409                 return $this->loaded;
 410         }
 411
 412         /**
 413          * Fully expand autoloader paths
 414          *
 415          * @param string $dir
 416          * @param array $files
 417          * @return array
 418          */
 419         protected function processAutoLoader( $dir, array $files ) {
 420                 // Make paths absolute, relative to the JSON file
 421                 foreach ( $files as &$file ) {
 422                         $file = "$dir/$file";
 423                 }
 424                 return $files;
 425         }
 426 }