includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 /**
   4  * ExtensionRegistry class
   5  *
   6  * The Registry loads JSON files, and uses a Processor
   7  * to extract information from them. It also registers
   8  * classes with the autoloader.
   9  *
  10  * @since 1.25
  11  */
  12 class ExtensionRegistry {
  13
  14         /**
  15          * Version of the highest supported manifest version
  16          */
  17         const MANIFEST_VERSION = 1;
  18
  19         /**
  20          * Version of the oldest supported manifest version
  21          */
  22         const OLDEST_MANIFEST_VERSION = 1;
  23
  24         /**
  25          * @var BagOStuff
  26          */
  27         protected $cache;
  28
  29         /**
  30          * Array of loaded things, keyed by name, values are credits information
  31          *
  32          * @var array
  33          */
  34         private $loaded = array();
  35
  36         /**
  37          * List of paths that should be loaded
  38          *
  39          * @var array
  40          */
  41         protected $queued = array();
  42
  43         /**
  44          * Items in the JSON file that aren't being
  45          * set as globals
  46          *
  47          * @var array
  48          */
  49         protected $attributes = array();
  50
  51         /**
  52          * @var ExtensionRegistry
  53          */
  54         private static $instance;
  55
  56         /**
  57          * @return ExtensionRegistry
  58          */
  59         public static function getInstance() {
  60                 if ( self::$instance === null ) {
  61                         self::$instance = new self();
  62                 }
  63
  64                 return self::$instance;
  65         }
  66
  67         public function __construct() {
  68                 // We use a try/catch instead of the $fallback parameter because
  69                 // we don't want to fail here if $wgObjectCaches is not configured
  70                 // properly for APC setup
  71                 try {
  72                         $this->cache = ObjectCache::newAccelerator( array() );
  73                 } catch ( MWException $e ) {
  74                         $this->cache = new EmptyBagOStuff();
  75                 }
  76         }
  77
  78         /**
  79          * @param string $path Absolute path to the JSON file
  80          */
  81         public function queue( $path ) {
  82                 global $wgExtensionInfoMTime;
  83
  84                 $mtime = $wgExtensionInfoMTime;
  85                 if ( $mtime === false ) {
  86                         if ( file_exists( $path ) ) {
  87                                 $mtime = filemtime( $path );
  88                         } else {
  89                                 throw new Exception( "$path does not exist!" );
  90                         }
  91                         if ( !$mtime ) {
  92                                 $err = error_get_last();
  93                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
  94                         }
  95                 }
  96                 $this->queued[$path] = $mtime;
  97         }
  98
  99         public function loadFromQueue() {
 100                 if ( !$this->queued ) {
 101                         return;
 102                 }
 103
 104                 // See if this queue is in APC
 105                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
 106                 $data = $this->cache->get( $key );
 107                 if ( $data ) {
 108                         $this->exportExtractedData( $data );
 109                 } else {
 110                         $data = $this->readFromQueue( $this->queued );
 111                         $this->exportExtractedData( $data );
 112                         // Do this late since we don't want to extract it since we already
 113                         // did that, but it should be cached
 114                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 115                         unset( $data['autoload'] );
 116                         $this->cache->set( $key, $data, 60 * 60 * 24 );
 117                 }
 118                 $this->queued = array();
 119         }
 120
 121         /**
 122          * Get the current load queue. Not intended to be used
 123          * outside of the installer.
 124          *
 125          * @return array
 126          */
 127         public function getQueue() {
 128                 return $this->queued;
 129         }
 130
 131         /**
 132          * Clear the current load queue. Not intended to be used
 133          * outside of the installer.
 134          */
 135         public function clearQueue() {
 136                 $this->queued = array();
 137         }
 138
 139         /**
 140          * Process a queue of extensions and return their extracted data
 141          *
 142          * @param array $queue keys are filenames, values are ignored
 143          * @return array extracted info
 144          * @throws Exception
 145          */
 146         public function readFromQueue( array $queue ) {
 147                 $autoloadClasses = array();
 148                 $processor = new ExtensionProcessor();
 149                 foreach ( $queue as $path => $mtime ) {
 150                         $json = file_get_contents( $path );
 151                         if ( $json === false ) {
 152                                 throw new Exception( "Unable to read $path, does it exist?" );
 153                         }
 154                         $info = json_decode( $json, /* $assoc = */ true );
 155                         if ( !is_array( $info ) ) {
 156                                 throw new Exception( "$path is not a valid JSON file." );
 157                         }
 158                         if ( !isset( $info['manifest_version'] ) ) {
 159                                 // For backwards-compatability, assume a version of 1
 160                                 $info['manifest_version'] = 1;
 161                         }
 162                         $version = $info['manifest_version'];
 163                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 164                                 throw new Exception( "$path: unsupported manifest_version: {$version}" );
 165                         }
 166                         $autoload = $this->processAutoLoader( dirname( $path ), $info );
 167                         // Set up the autoloader now so custom processors will work
 168                         $GLOBALS['wgAutoloadClasses'] += $autoload;
 169                         $autoloadClasses += $autoload;
 170                         $processor->extractInfo( $path, $info, $version );
 171                 }
 172                 $data = $processor->getExtractedInfo();
 173                 // Need to set this so we can += to it later
 174                 $data['globals']['wgAutoloadClasses'] = array();
 175                 foreach ( $data['credits'] as $credit ) {
 176                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 177                 }
 178                 $data['autoload'] = $autoloadClasses;
 179                 return $data;
 180         }
 181
 182         protected function exportExtractedData( array $info ) {
 183                 foreach ( $info['globals'] as $key => $val ) {
 184                         if ( !isset( $GLOBALS[$key] ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 185                                 $GLOBALS[$key] = $val;
 186                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 187                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 188                                 // Ideally it would have been taken care of in the first if block though.
 189                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 190                         } elseif ( $key === 'wgGroupPermissions' ) {
 191                                 // First merge individual groups
 192                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 193                                         if ( isset( $val[$name] ) ) {
 194                                                 $groupVal += $val[$name];
 195                                         }
 196                                 }
 197                                 // Now merge groups that didn't exist yet
 198                                 $GLOBALS[$key] += $val;
 199                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 200                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 201                         } // else case is a config setting where it has already been overriden, so don't set it
 202                 }
 203                 foreach ( $info['defines'] as $name => $val ) {
 204                         define( $name, $val );
 205                 }
 206                 foreach ( $info['callbacks'] as $cb ) {
 207                         call_user_func( $cb );
 208                 }
 209
 210                 $this->loaded += $info['credits'];
 211
 212                 if ( $info['attributes'] ) {
 213                         if ( !$this->attributes ) {
 214                                 $this->attributes = $info['attributes'];
 215                         } else {
 216                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 217                         }
 218                 }
 219         }
 220
 221         /**
 222          * Loads and processes the given JSON file without delay
 223          *
 224          * If some extensions are already queued, this will load
 225          * those as well.
 226          *
 227          * @param string $path Absolute path to the JSON file
 228          */
 229         public function load( $path ) {
 230                 $this->loadFromQueue(); // First clear the queue
 231                 $this->queue( $path );
 232                 $this->loadFromQueue();
 233         }
 234
 235         /**
 236          * Whether a thing has been loaded
 237          * @param string $name
 238          * @return bool
 239          */
 240         public function isLoaded( $name ) {
 241                 return isset( $this->loaded[$name] );
 242         }
 243
 244         /**
 245          * @param string $name
 246          * @return array
 247          */
 248         public function getAttribute( $name ) {
 249                 if ( isset( $this->attributes[$name] ) ) {
 250                         return $this->attributes[$name];
 251                 } else {
 252                         return array();
 253                 }
 254         }
 255
 256         /**
 257          * Get information about all things
 258          *
 259          * @return array
 260          */
 261         public function getAllThings() {
 262                 return $this->loaded;
 263         }
 264
 265         /**
 266          * Mark a thing as loaded
 267          *
 268          * @param string $name
 269          * @param array $credits
 270          */
 271         protected function markLoaded( $name, array $credits ) {
 272                 $this->loaded[$name] = $credits;
 273         }
 274
 275         /**
 276          * Register classes with the autoloader
 277          *
 278          * @param string $dir
 279          * @param array $info
 280          * @return array
 281          */
 282         protected function processAutoLoader( $dir, array $info ) {
 283                 if ( isset( $info['AutoloadClasses'] ) ) {
 284                         // Make paths absolute, relative to the JSON file
 285                         return array_map( function( $file ) use ( $dir ) {
 286                                 return "$dir/$file";
 287                         }, $info['AutoloadClasses'] );
 288                 } else {
 289                         return array();
 290                 }
 291         }
 292 }