includes/filerepo/RepoGroup.php

   1 <?php
   2 /**
   3  * Prioritized list of file repositories.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup FileRepo
  22  */
  23
  24 /**
  25  * Prioritized list of file repositories
  26  *
  27  * @ingroup FileRepo
  28  */
  29 class RepoGroup {
  30         /** @var LocalRepo */
  31         protected $localRepo;
  32
  33         /** @var FileRepo[] */
  34         protected $foreignRepos;
  35
  36         /** @var bool */
  37         protected $reposInitialised = false;
  38
  39         /** @var array */
  40         protected $localInfo;
  41
  42         /** @var array */
  43         protected $foreignInfo;
  44
  45         /** @var ProcessCacheLRU */
  46         protected $cache;
  47
  48         /** @var RepoGroup */
  49         protected static $instance;
  50
  51         /** Maximum number of cache items */
  52         const MAX_CACHE_SIZE = 500;
  53
  54         /**
  55          * Get a RepoGroup instance. At present only one instance of RepoGroup is
  56          * needed in a MediaWiki invocation, this may change in the future.
  57          * @return RepoGroup
  58          */
  59         static function singleton() {
  60                 if ( self::$instance ) {
  61                         return self::$instance;
  62                 }
  63                 global $wgLocalFileRepo, $wgForeignFileRepos;
  64                 self::$instance = new RepoGroup( $wgLocalFileRepo, $wgForeignFileRepos );
  65
  66                 return self::$instance;
  67         }
  68
  69         /**
  70          * Destroy the singleton instance, so that a new one will be created next
  71          * time singleton() is called.
  72          */
  73         static function destroySingleton() {
  74                 self::$instance = null;
  75         }
  76
  77         /**
  78          * Set the singleton instance to a given object
  79          * Used by extensions which hook into the Repo chain.
  80          * It's not enough to just create a superclass ... you have
  81          * to get people to call into it even though all they know is RepoGroup::singleton()
  82          *
  83          * @param RepoGroup $instance
  84          */
  85         static function setSingleton( $instance ) {
  86                 self::$instance = $instance;
  87         }
  88
  89         /**
  90          * Construct a group of file repositories.
  91          *
  92          * @param array $localInfo Associative array for local repo's info
  93          * @param array $foreignInfo Array of repository info arrays.
  94          *   Each info array is an associative array with the 'class' member
  95          *   giving the class name. The entire array is passed to the repository
  96          *   constructor as the first parameter.
  97          */
  98         function __construct( $localInfo, $foreignInfo ) {
  99                 $this->localInfo = $localInfo;
 100                 $this->foreignInfo = $foreignInfo;
 101                 $this->cache = new ProcessCacheLRU( self::MAX_CACHE_SIZE );
 102         }
 103
 104         /**
 105          * Search repositories for an image.
 106          * You can also use wfFindFile() to do this.
 107          *
 108          * @param Title|string $title Title object or string
 109          * @param array $options Associative array of options:
 110          *   time:           requested time for an archived image, or false for the
 111          *                   current version. An image object will be returned which was
 112          *                   created at the specified time.
 113          *   ignoreRedirect: If true, do not follow file redirects
 114          *   private:        If true, return restricted (deleted) files if the current
 115          *                   user is allowed to view them. Otherwise, such files will not
 116          *                   be found.
 117          *   latest:         If true, load from the latest available data into File objects
 118          * @return File|bool False if title is not found
 119          */
 120         function findFile( $title, $options = [] ) {
 121                 if ( !is_array( $options ) ) {
 122                         // MW 1.15 compat
 123                         $options = [ 'time' => $options ];
 124                 }
 125                 if ( isset( $options['bypassCache'] ) ) {
 126                         $options['latest'] = $options['bypassCache']; // b/c
 127                 }
 128
 129                 if ( !$this->reposInitialised ) {
 130                         $this->initialiseRepos();
 131                 }
 132                 $title = File::normalizeTitle( $title );
 133                 if ( !$title ) {
 134                         return false;
 135                 }
 136
 137                 # Check the cache
 138                 $dbkey = $title->getDBkey();
 139                 if ( empty( $options['ignoreRedirect'] )
 140                         && empty( $options['private'] )
 141                         && empty( $options['bypassCache'] )
 142                 ) {
 143                         $time = isset( $options['time'] ) ? $options['time'] : '';
 144                         if ( $this->cache->has( $dbkey, $time, 60 ) ) {
 145                                 return $this->cache->get( $dbkey, $time );
 146                         }
 147                         $useCache = true;
 148                 } else {
 149                         $time = false;
 150                         $useCache = false;
 151                 }
 152
 153                 # Check the local repo
 154                 $image = $this->localRepo->findFile( $title, $options );
 155
 156                 # Check the foreign repos
 157                 if ( !$image ) {
 158                         foreach ( $this->foreignRepos as $repo ) {
 159                                 $image = $repo->findFile( $title, $options );
 160                                 if ( $image ) {
 161                                         break;
 162                                 }
 163                         }
 164                 }
 165
 166                 $image = $image ? $image : false; // type sanity
 167                 # Cache file existence or non-existence
 168                 if ( $useCache && ( !$image || $image->isCacheable() ) ) {
 169                         $this->cache->set( $dbkey, $time, $image );
 170                 }
 171
 172                 return $image;
 173         }
 174
 175         /**
 176          * Search repositories for many files at once.
 177          *
 178          * @param array $inputItems An array of titles, or an array of findFile() options with
 179          *    the "title" option giving the title. Example:
 180          *
 181          *     $findItem = [ 'title' => $title, 'private' => true ];
 182          *     $findBatch = [ $findItem ];
 183          *     $repo->findFiles( $findBatch );
 184          *
 185          *    No title should appear in $items twice, as the result use titles as keys
 186          * @param int $flags Supports:
 187          *     - FileRepo::NAME_AND_TIME_ONLY : return a (search title => (title,timestamp)) map.
 188          *       The search title uses the input titles; the other is the final post-redirect title.
 189          *       All titles are returned as string DB keys and the inner array is associative.
 190          * @return array Map of (file name => File objects) for matches
 191          */
 192         function findFiles( array $inputItems, $flags = 0 ) {
 193                 if ( !$this->reposInitialised ) {
 194                         $this->initialiseRepos();
 195                 }
 196
 197                 $items = [];
 198                 foreach ( $inputItems as $item ) {
 199                         if ( !is_array( $item ) ) {
 200                                 $item = [ 'title' => $item ];
 201                         }
 202                         $item['title'] = File::normalizeTitle( $item['title'] );
 203                         if ( $item['title'] ) {
 204                                 $items[$item['title']->getDBkey()] = $item;
 205                         }
 206                 }
 207
 208                 $images = $this->localRepo->findFiles( $items, $flags );
 209
 210                 foreach ( $this->foreignRepos as $repo ) {
 211                         // Remove found files from $items
 212                         foreach ( $images as $name => $image ) {
 213                                 unset( $items[$name] );
 214                         }
 215
 216                         $images = array_merge( $images, $repo->findFiles( $items, $flags ) );
 217                 }
 218
 219                 return $images;
 220         }
 221
 222         /**
 223          * Interface for FileRepo::checkRedirect()
 224          * @param Title $title
 225          * @return bool|Title
 226          */
 227         function checkRedirect( Title $title ) {
 228                 if ( !$this->reposInitialised ) {
 229                         $this->initialiseRepos();
 230                 }
 231
 232                 $redir = $this->localRepo->checkRedirect( $title );
 233                 if ( $redir ) {
 234                         return $redir;
 235                 }
 236
 237                 foreach ( $this->foreignRepos as $repo ) {
 238                         $redir = $repo->checkRedirect( $title );
 239                         if ( $redir ) {
 240                                 return $redir;
 241                         }
 242                 }
 243
 244                 return false;
 245         }
 246
 247         /**
 248          * Find an instance of the file with this key, created at the specified time
 249          * Returns false if the file does not exist.
 250          *
 251          * @param string $hash Base 36 SHA-1 hash
 252          * @param array $options Option array, same as findFile()
 253          * @return File|bool File object or false if it is not found
 254          */
 255         function findFileFromKey( $hash, $options = [] ) {
 256                 if ( !$this->reposInitialised ) {
 257                         $this->initialiseRepos();
 258                 }
 259
 260                 $file = $this->localRepo->findFileFromKey( $hash, $options );
 261                 if ( !$file ) {
 262                         foreach ( $this->foreignRepos as $repo ) {
 263                                 $file = $repo->findFileFromKey( $hash, $options );
 264                                 if ( $file ) {
 265                                         break;
 266                                 }
 267                         }
 268                 }
 269
 270                 return $file;
 271         }
 272
 273         /**
 274          * Find all instances of files with this key
 275          *
 276          * @param string $hash Base 36 SHA-1 hash
 277          * @return File[]
 278          */
 279         function findBySha1( $hash ) {
 280                 if ( !$this->reposInitialised ) {
 281                         $this->initialiseRepos();
 282                 }
 283
 284                 $result = $this->localRepo->findBySha1( $hash );
 285                 foreach ( $this->foreignRepos as $repo ) {
 286                         $result = array_merge( $result, $repo->findBySha1( $hash ) );
 287                 }
 288                 usort( $result, 'File::compare' );
 289
 290                 return $result;
 291         }
 292
 293         /**
 294          * Find all instances of files with this keys
 295          *
 296          * @param array $hashes Base 36 SHA-1 hashes
 297          * @return array Array of array of File objects
 298          */
 299         function findBySha1s( array $hashes ) {
 300                 if ( !$this->reposInitialised ) {
 301                         $this->initialiseRepos();
 302                 }
 303
 304                 $result = $this->localRepo->findBySha1s( $hashes );
 305                 foreach ( $this->foreignRepos as $repo ) {
 306                         $result = array_merge_recursive( $result, $repo->findBySha1s( $hashes ) );
 307                 }
 308                 // sort the merged (and presorted) sublist of each hash
 309                 foreach ( $result as $hash => $files ) {
 310                         usort( $result[$hash], 'File::compare' );
 311                 }
 312
 313                 return $result;
 314         }
 315
 316         /**
 317          * Get the repo instance with a given key.
 318          * @param string|int $index
 319          * @return bool|LocalRepo
 320          */
 321         function getRepo( $index ) {
 322                 if ( !$this->reposInitialised ) {
 323                         $this->initialiseRepos();
 324                 }
 325                 if ( $index === 'local' ) {
 326                         return $this->localRepo;
 327                 } elseif ( isset( $this->foreignRepos[$index] ) ) {
 328                         return $this->foreignRepos[$index];
 329                 } else {
 330                         return false;
 331                 }
 332         }
 333
 334         /**
 335          * Get the repo instance by its name
 336          * @param string $name
 337          * @return bool
 338          */
 339         function getRepoByName( $name ) {
 340                 if ( !$this->reposInitialised ) {
 341                         $this->initialiseRepos();
 342                 }
 343                 foreach ( $this->foreignRepos as $repo ) {
 344                         if ( $repo->name == $name ) {
 345                                 return $repo;
 346                         }
 347                 }
 348
 349                 return false;
 350         }
 351
 352         /**
 353          * Get the local repository, i.e. the one corresponding to the local image
 354          * table. Files are typically uploaded to the local repository.
 355          *
 356          * @return LocalRepo
 357          */
 358         function getLocalRepo() {
 359                 return $this->getRepo( 'local' );
 360         }
 361
 362         /**
 363          * Call a function for each foreign repo, with the repo object as the
 364          * first parameter.
 365          *
 366          * @param callable $callback The function to call
 367          * @param array $params Optional additional parameters to pass to the function
 368          * @return bool
 369          */
 370         function forEachForeignRepo( $callback, $params = [] ) {
 371                 if ( !$this->reposInitialised ) {
 372                         $this->initialiseRepos();
 373                 }
 374                 foreach ( $this->foreignRepos as $repo ) {
 375                         $args = array_merge( [ $repo ], $params );
 376                         if ( call_user_func_array( $callback, $args ) ) {
 377                                 return true;
 378                         }
 379                 }
 380
 381                 return false;
 382         }
 383
 384         /**
 385          * Does the installation have any foreign repos set up?
 386          * @return bool
 387          */
 388         function hasForeignRepos() {
 389                 if ( !$this->reposInitialised ) {
 390                         $this->initialiseRepos();
 391                 }
 392                 return (bool)$this->foreignRepos;
 393         }
 394
 395         /**
 396          * Initialise the $repos array
 397          */
 398         function initialiseRepos() {
 399                 if ( $this->reposInitialised ) {
 400                         return;
 401                 }
 402                 $this->reposInitialised = true;
 403
 404                 $this->localRepo = $this->newRepo( $this->localInfo );
 405                 $this->foreignRepos = [];
 406                 foreach ( $this->foreignInfo as $key => $info ) {
 407                         $this->foreignRepos[$key] = $this->newRepo( $info );
 408                 }
 409         }
 410
 411         /**
 412          * Create a repo class based on an info structure
 413          * @param array $info
 414          * @return FileRepo
 415          */
 416         protected function newRepo( $info ) {
 417                 $class = $info['class'];
 418
 419                 return new $class( $info );
 420         }
 421
 422         /**
 423          * Split a virtual URL into repo, zone and rel parts
 424          * @param string $url
 425          * @throws MWException
 426          * @return array Containing repo, zone and rel
 427          */
 428         function splitVirtualUrl( $url ) {
 429                 if ( substr( $url, 0, 9 ) != 'mwrepo://' ) {
 430                         throw new MWException( __METHOD__ . ': unknown protocol' );
 431                 }
 432
 433                 $bits = explode( '/', substr( $url, 9 ), 3 );
 434                 if ( count( $bits ) != 3 ) {
 435                         throw new MWException( __METHOD__ . ": invalid mwrepo URL: $url" );
 436                 }
 437
 438                 return $bits;
 439         }
 440
 441         /**
 442          * @param string $fileName
 443          * @return array
 444          */
 445         function getFileProps( $fileName ) {
 446                 if ( FileRepo::isVirtualUrl( $fileName ) ) {
 447                         list( $repoName, /* $zone */, /* $rel */ ) = $this->splitVirtualUrl( $fileName );
 448                         if ( $repoName === '' ) {
 449                                 $repoName = 'local';
 450                         }
 451                         $repo = $this->getRepo( $repoName );
 452
 453                         return $repo->getFileProps( $fileName );
 454                 } else {
 455                         $mwProps = new MWFileProps( MimeMagic::singleton() );
 456
 457                         return $mwProps->getPropsFromPath( $fileName, true );
 458                 }
 459         }
 460
 461         /**
 462          * Clear RepoGroup process cache used for finding a file
 463          * @param Title|null $title Title of the file or null to clear all files
 464          */
 465         public function clearCache( Title $title = null ) {
 466                 if ( $title == null ) {
 467                         $this->cache->clear();
 468                 } else {
 469                         $this->cache->clear( $title->getDBkey() );
 470                 }
 471         }
 472 }