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          * Processors, 'default' should be set by subclasses in the constructor
  43          *
  44          * @var Processor[]
  45          */
  46         protected $processors = array();
  47
  48         /**
  49          * @var ExtensionRegistry
  50          */
  51         private static $instance;
  52
  53         /**
  54          * @return ExtensionRegistry
  55          */
  56         public static function getInstance() {
  57                 if ( self::$instance === null ) {
  58                         self::$instance = new self();
  59                 }
  60
  61                 return self::$instance;
  62         }
  63
  64         public function __construct() {
  65                 // We use a try/catch instead of the $fallback parameter because
  66                 // we don't want to fail here if $wgObjectCaches is not configured
  67                 // properly for APC setup
  68                 try {
  69                         $this->cache = ObjectCache::newAccelerator( array() );
  70                 } catch ( MWException $e ) {
  71                         $this->cache = new EmptyBagOStuff();
  72                 }
  73         }
  74
  75         /**
  76          * @param string $path Absolute path to the JSON file
  77          */
  78         public function queue( $path ) {
  79                 global $wgExtensionInfoMTime;
  80                 if ( $wgExtensionInfoMTime !== false ) {
  81                         $mtime = $wgExtensionInfoMTime;
  82                 } else {
  83                         $mtime = filemtime( $path );
  84                 }
  85                 $this->queued[$path] = $mtime;
  86         }
  87
  88         public function loadFromQueue() {
  89                 if ( !$this->queued ) {
  90                         return;
  91                 }
  92
  93                 // See if this queue is in APC
  94                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
  95                 $data = $this->cache->get( $key );
  96                 if ( $data ) {
  97                         $this->exportExtractedData( $data );
  98                 } else {
  99                         $data = $this->readFromQueue( $this->queued );
 100                         $this->exportExtractedData( $data );
 101                         // Do this late since we don't want to extract it since we already
 102                         // did that, but it should be cached
 103                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 104                         unset( $data['autoload'] );
 105                         $this->cache->set( $key, $data );
 106                 }
 107                 $this->queued = array();
 108         }
 109
 110         /**
 111          * Process a queue of extensions and return their extracted data
 112          *
 113          * @param array $queue keys are filenames, values are ignored
 114          * @return array extracted info
 115          * @throws Exception
 116          */
 117         public function readFromQueue( array $queue ) {
 118                 $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
 119                 $autoloadClasses = array();
 120                 foreach ( $queue as $path => $mtime ) {
 121                         $json = file_get_contents( $path );
 122                         if ( $json === false ) {
 123                                 throw new Exception( "Unable to read $path, does it exist?" );
 124                         }
 125                         $info = json_decode( $json, /* $assoc = */ true );
 126                         if ( !is_array( $info ) ) {
 127                                 throw new Exception( "$path is not a valid JSON file." );
 128                         }
 129                         $autoload = $this->processAutoLoader( dirname( $path ), $info );
 130                         // Set up the autoloader now so custom processors will work
 131                         $GLOBALS['wgAutoloadClasses'] += $autoload;
 132                         $autoloadClasses += $autoload;
 133                         if ( isset( $info['processor'] ) ) {
 134                                 $processor = $this->getProcessor( $info['processor'] );
 135                         } else {
 136                                 $processor = $this->getProcessor( 'default' );
 137                         }
 138                         $processor->extractInfo( $path, $info );
 139                 }
 140                 foreach ( $this->processors as $processor ) {
 141                         $data = array_merge_recursive( $data, $processor->getExtractedInfo() );
 142                 }
 143                 foreach ( $data['credits'] as $credit ) {
 144                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 145                 }
 146                 $this->processors = array(); // Reset
 147                 $data['autoload'] = $autoloadClasses;
 148                 return $data;
 149         }
 150
 151         protected function getProcessor( $type ) {
 152                 if ( !isset( $this->processors[$type] ) ) {
 153                         $processor = $type === 'default' ? new ExtensionProcessor() : new $type();
 154                         if ( !$processor instanceof Processor ) {
 155                                 throw new Exception( "$type is not a Processor" );
 156                         }
 157                         $this->processors[$type] = $processor;
 158                 }
 159
 160                 return $this->processors[$type];
 161         }
 162
 163         protected function exportExtractedData( array $info ) {
 164                 foreach ( $info['globals'] as $key => $val ) {
 165                         if ( !isset( $GLOBALS[$key] ) || !$GLOBALS[$key] ) {
 166                                 $GLOBALS[$key] = $val;
 167                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 168                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 169                                 // Ideally it would have been taken care of in the first if block though.
 170                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 171                         } elseif ( $key === 'wgGroupPermissions' ) {
 172                                 // First merge individual groups
 173                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 174                                         if ( isset( $val[$name] ) ) {
 175                                                 $groupVal += $val[$name];
 176                                         }
 177                                 }
 178                                 // Now merge groups that didn't exist yet
 179                                 $GLOBALS[$key] += $val;
 180                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 181                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 182                         } // else case is a config setting where it has already been overriden, so don't set it
 183                 }
 184                 foreach ( $info['defines'] as $name => $val ) {
 185                         define( $name, $val );
 186                 }
 187                 foreach ( $info['callbacks'] as $cb ) {
 188                         call_user_func( $cb );
 189                 }
 190
 191                 $this->loaded += $info['credits'];
 192
 193                 if ( $info['attributes'] ) {
 194                         if ( !$this->attributes ) {
 195                                 $this->attributes = $info['attributes'];
 196                         } else {
 197                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 198                         }
 199                 }
 200         }
 201
 202         /**
 203          * Loads and processes the given JSON file without delay
 204          *
 205          * If some extensions are already queued, this will load
 206          * those as well.
 207          *
 208          * @param string $path Absolute path to the JSON file
 209          */
 210         public function load( $path ) {
 211                 $this->loadFromQueue(); // First clear the queue
 212                 $this->queue( $path );
 213                 $this->loadFromQueue();
 214         }
 215
 216         /**
 217          * Whether a thing has been loaded
 218          * @param string $name
 219          * @return bool
 220          */
 221         public function isLoaded( $name ) {
 222                 return isset( $this->loaded[$name] );
 223         }
 224
 225         /**
 226          * @param string $name
 227          * @return array
 228          */
 229         public function getAttribute( $name ) {
 230                 if ( isset( $this->attributes[$name] ) ) {
 231                         return $this->attributes[$name];
 232                 } else {
 233                         return array();
 234                 }
 235         }
 236
 237         /**
 238          * Get information about all things
 239          *
 240          * @return array
 241          */
 242         public function getAllThings() {
 243                 return $this->loaded;
 244         }
 245
 246         /**
 247          * Mark a thing as loaded
 248          *
 249          * @param string $name
 250          * @param array $credits
 251          */
 252         protected function markLoaded( $name, array $credits ) {
 253                 $this->loaded[$name] = $credits;
 254         }
 255
 256         /**
 257          * Register classes with the autoloader
 258          *
 259          * @param string $dir
 260          * @param array $info
 261          * @return array
 262          */
 263         protected function processAutoLoader( $dir, array $info ) {
 264                 if ( isset( $info['AutoloadClasses'] ) ) {
 265                         // Make paths absolute, relative to the JSON file
 266                         return array_map( function( $file ) use ( $dir ) {
 267                                 return "$dir/$file";
 268                         }, $info['AutoloadClasses'] );
 269                 } else {
 270                         return array();
 271                 }
 272         }
 273 }