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                 // See if this queue is in APC
  87                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
  88                 $data = $this->cache->get( $key );
  89                 if ( $data ) {
  90                         $this->exportExtractedData( $data );
  91                 } else {
  92                         $data = $this->readFromQueue( $this->queued );
  93                         $this->exportExtractedData( $data );
  94                         // Do this late since we don't want to extract it since we already
  95                         // did that, but it should be cached
  96                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
  97                         unset( $data['autoload'] );
  98                         $this->cache->set( $key, $data, 60 * 60 * 24 );
  99                 }
 100                 $this->queued = array();
 101         }
 102
 103         /**
 104          * Process a queue of extensions and return their extracted data
 105          *
 106          * @param array $queue keys are filenames, values are ignored
 107          * @return array extracted info
 108          * @throws Exception
 109          */
 110         public function readFromQueue( array $queue ) {
 111                 $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
 112                 $autoloadClasses = array();
 113                 $processor = new ExtensionProcessor();
 114                 foreach ( $queue as $path => $mtime ) {
 115                         $json = file_get_contents( $path );
 116                         if ( $json === false ) {
 117                                 throw new Exception( "Unable to read $path, does it exist?" );
 118                         }
 119                         $info = json_decode( $json, /* $assoc = */ true );
 120                         if ( !is_array( $info ) ) {
 121                                 throw new Exception( "$path is not a valid JSON file." );
 122                         }
 123                         $autoload = $this->processAutoLoader( dirname( $path ), $info );
 124                         // Set up the autoloader now so custom processors will work
 125                         $GLOBALS['wgAutoloadClasses'] += $autoload;
 126                         $autoloadClasses += $autoload;
 127                         $processor->extractInfo( $path, $info );
 128                 }
 129                 $data = $processor->getExtractedInfo();
 130                 // Need to set this so we can += to it later
 131                 $data['globals']['wgAutoloadClasses'] = array();
 132                 foreach ( $data['credits'] as $credit ) {
 133                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 134                 }
 135                 $data['autoload'] = $autoloadClasses;
 136                 return $data;
 137         }
 138
 139         protected function exportExtractedData( array $info ) {
 140                 foreach ( $info['globals'] as $key => $val ) {
 141                         if ( !isset( $GLOBALS[$key] ) || !$GLOBALS[$key] ) {
 142                                 $GLOBALS[$key] = $val;
 143                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 144                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 145                                 // Ideally it would have been taken care of in the first if block though.
 146                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 147                         } elseif ( $key === 'wgGroupPermissions' ) {
 148                                 // First merge individual groups
 149                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 150                                         if ( isset( $val[$name] ) ) {
 151                                                 $groupVal += $val[$name];
 152                                         }
 153                                 }
 154                                 // Now merge groups that didn't exist yet
 155                                 $GLOBALS[$key] += $val;
 156                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 157                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 158                         } // else case is a config setting where it has already been overriden, so don't set it
 159                 }
 160                 foreach ( $info['defines'] as $name => $val ) {
 161                         define( $name, $val );
 162                 }
 163                 foreach ( $info['callbacks'] as $cb ) {
 164                         call_user_func( $cb );
 165                 }
 166
 167                 $this->loaded += $info['credits'];
 168
 169                 if ( $info['attributes'] ) {
 170                         if ( !$this->attributes ) {
 171                                 $this->attributes = $info['attributes'];
 172                         } else {
 173                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 174                         }
 175                 }
 176         }
 177
 178         /**
 179          * Loads and processes the given JSON file without delay
 180          *
 181          * If some extensions are already queued, this will load
 182          * those as well.
 183          *
 184          * @param string $path Absolute path to the JSON file
 185          */
 186         public function load( $path ) {
 187                 $this->loadFromQueue(); // First clear the queue
 188                 $this->queue( $path );
 189                 $this->loadFromQueue();
 190         }
 191
 192         /**
 193          * Whether a thing has been loaded
 194          * @param string $name
 195          * @return bool
 196          */
 197         public function isLoaded( $name ) {
 198                 return isset( $this->loaded[$name] );
 199         }
 200
 201         /**
 202          * @param string $name
 203          * @return array
 204          */
 205         public function getAttribute( $name ) {
 206                 if ( isset( $this->attributes[$name] ) ) {
 207                         return $this->attributes[$name];
 208                 } else {
 209                         return array();
 210                 }
 211         }
 212
 213         /**
 214          * Get information about all things
 215          *
 216          * @return array
 217          */
 218         public function getAllThings() {
 219                 return $this->loaded;
 220         }
 221
 222         /**
 223          * Mark a thing as loaded
 224          *
 225          * @param string $name
 226          * @param array $credits
 227          */
 228         protected function markLoaded( $name, array $credits ) {
 229                 $this->loaded[$name] = $credits;
 230         }
 231
 232         /**
 233          * Register classes with the autoloader
 234          *
 235          * @param string $dir
 236          * @param array $info
 237          * @return array
 238          */
 239         protected function processAutoLoader( $dir, array $info ) {
 240                 if ( isset( $info['AutoloadClasses'] ) ) {
 241                         // Make paths absolute, relative to the JSON file
 242                         return array_map( function( $file ) use ( $dir ) {
 243                                 return "$dir/$file";
 244                         }, $info['AutoloadClasses'] );
 245                 } else {
 246                         return array();
 247                 }
 248         }
 249 }