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