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                 if ( empty( $options['ignoreRedirect'] )
 139                         && empty( $options['private'] )
 140                         && empty( $options['bypassCache'] )
 141                 ) {
 142                         $time = isset( $options['time'] ) ? $options['time'] : '';
 143                         $dbkey = $title->getDBkey();
 144                         if ( $this->cache->has( $dbkey, $time, 60 ) ) {
 145                                 return $this->cache->get( $dbkey, $time );
 146                         }
 147                         $useCache = true;
 148                 } else {
 149                         $useCache = false;
 150                 }
 151
 152                 # Check the local repo
 153                 $image = $this->localRepo->findFile( $title, $options );
 154
 155                 # Check the foreign repos
 156                 if ( !$image ) {
 157                         foreach ( $this->foreignRepos as $repo ) {
 158                                 $image = $repo->findFile( $title, $options );
 159                                 if ( $image ) {
 160                                         break;
 161                                 }
 162                         }
 163                 }
 164
 165                 $image = $image ? $image : false; // type sanity
 166                 # Cache file existence or non-existence
 167                 if ( $useCache && ( !$image || $image->isCacheable() ) ) {
 168                         $this->cache->set( $dbkey, $time, $image );
 169                 }
 170
 171                 return $image;
 172         }
 173
 174         /**
 175          * Search repositories for many files at once.
 176          *
 177          * @param array $inputItems An array of titles, or an array of findFile() options with
 178          *    the "title" option giving the title. Example:
 179          *
 180          *     $findItem = array( 'title' => $title, 'private' => true );
 181          *     $findBatch = array( $findItem );
 182          *     $repo->findFiles( $findBatch );
 183          *
 184          *    No title should appear in $items twice, as the result use titles as keys
 185          * @param int $flags Supports:
 186          *     - FileRepo::NAME_AND_TIME_ONLY : return a (search title => (title,timestamp)) map.
 187          *       The search title uses the input titles; the other is the final post-redirect title.
 188          *       All titles are returned as string DB keys and the inner array is associative.
 189          * @return array Map of (file name => File objects) for matches
 190          */
 191         function findFiles( array $inputItems, $flags = 0 ) {
 192                 if ( !$this->reposInitialised ) {
 193                         $this->initialiseRepos();
 194                 }
 195
 196                 $items = [];
 197                 foreach ( $inputItems as $item ) {
 198                         if ( !is_array( $item ) ) {
 199                                 $item = [ 'title' => $item ];
 200                         }
 201                         $item['title'] = File::normalizeTitle( $item['title'] );
 202                         if ( $item['title'] ) {
 203                                 $items[$item['title']->getDBkey()] = $item;
 204                         }
 205                 }
 206
 207                 $images = $this->localRepo->findFiles( $items, $flags );
 208
 209                 foreach ( $this->foreignRepos as $repo ) {
 210                         // Remove found files from $items
 211                         foreach ( $images as $name => $image ) {
 212                                 unset( $items[$name] );
 213                         }
 214
 215                         $images = array_merge( $images, $repo->findFiles( $items, $flags ) );
 216                 }
 217
 218                 return $images;
 219         }
 220
 221         /**
 222          * Interface for FileRepo::checkRedirect()
 223          * @param Title $title
 224          * @return bool|Title
 225          */
 226         function checkRedirect( Title $title ) {
 227                 if ( !$this->reposInitialised ) {
 228                         $this->initialiseRepos();
 229                 }
 230
 231                 $redir = $this->localRepo->checkRedirect( $title );
 232                 if ( $redir ) {
 233                         return $redir;
 234                 }
 235
 236                 foreach ( $this->foreignRepos as $repo ) {
 237                         $redir = $repo->checkRedirect( $title );
 238                         if ( $redir ) {
 239                                 return $redir;
 240                         }
 241                 }
 242
 243                 return false;
 244         }
 245
 246         /**
 247          * Find an instance of the file with this key, created at the specified time
 248          * Returns false if the file does not exist.
 249          *
 250          * @param string $hash Base 36 SHA-1 hash
 251          * @param array $options Option array, same as findFile()
 252          * @return File|bool File object or false if it is not found
 253          */
 254         function findFileFromKey( $hash, $options = [] ) {
 255                 if ( !$this->reposInitialised ) {
 256                         $this->initialiseRepos();
 257                 }
 258
 259                 $file = $this->localRepo->findFileFromKey( $hash, $options );
 260                 if ( !$file ) {
 261                         foreach ( $this->foreignRepos as $repo ) {
 262                                 $file = $repo->findFileFromKey( $hash, $options );
 263                                 if ( $file ) {
 264                                         break;
 265                                 }
 266                         }
 267                 }
 268
 269                 return $file;
 270         }
 271
 272         /**
 273          * Find all instances of files with this key
 274          *
 275          * @param string $hash Base 36 SHA-1 hash
 276          * @return File[]
 277          */
 278         function findBySha1( $hash ) {
 279                 if ( !$this->reposInitialised ) {
 280                         $this->initialiseRepos();
 281                 }
 282
 283                 $result = $this->localRepo->findBySha1( $hash );
 284                 foreach ( $this->foreignRepos as $repo ) {
 285                         $result = array_merge( $result, $repo->findBySha1( $hash ) );
 286                 }
 287                 usort( $result, 'File::compare' );
 288
 289                 return $result;
 290         }
 291
 292         /**
 293          * Find all instances of files with this keys
 294          *
 295          * @param array $hashes Base 36 SHA-1 hashes
 296          * @return array Array of array of File objects
 297          */
 298         function findBySha1s( array $hashes ) {
 299                 if ( !$this->reposInitialised ) {
 300                         $this->initialiseRepos();
 301                 }
 302
 303                 $result = $this->localRepo->findBySha1s( $hashes );
 304                 foreach ( $this->foreignRepos as $repo ) {
 305                         $result = array_merge_recursive( $result, $repo->findBySha1s( $hashes ) );
 306                 }
 307                 // sort the merged (and presorted) sublist of each hash
 308                 foreach ( $result as $hash => $files ) {
 309                         usort( $result[$hash], 'File::compare' );
 310                 }
 311
 312                 return $result;
 313         }
 314
 315         /**
 316          * Get the repo instance with a given key.
 317          * @param string|int $index
 318          * @return bool|LocalRepo
 319          */
 320         function getRepo( $index ) {
 321                 if ( !$this->reposInitialised ) {
 322                         $this->initialiseRepos();
 323                 }
 324                 if ( $index === 'local' ) {
 325                         return $this->localRepo;
 326                 } elseif ( isset( $this->foreignRepos[$index] ) ) {
 327                         return $this->foreignRepos[$index];
 328                 } else {
 329                         return false;
 330                 }
 331         }
 332
 333         /**
 334          * Get the repo instance by its name
 335          * @param string $name
 336          * @return bool
 337          */
 338         function getRepoByName( $name ) {
 339                 if ( !$this->reposInitialised ) {
 340                         $this->initialiseRepos();
 341                 }
 342                 foreach ( $this->foreignRepos as $repo ) {
 343                         if ( $repo->name == $name ) {
 344                                 return $repo;
 345                         }
 346                 }
 347
 348                 return false;
 349         }
 350
 351         /**
 352          * Get the local repository, i.e. the one corresponding to the local image
 353          * table. Files are typically uploaded to the local repository.
 354          *
 355          * @return LocalRepo
 356          */
 357         function getLocalRepo() {
 358                 return $this->getRepo( 'local' );
 359         }
 360
 361         /**
 362          * Call a function for each foreign repo, with the repo object as the
 363          * first parameter.
 364          *
 365          * @param callable $callback The function to call
 366          * @param array $params Optional additional parameters to pass to the function
 367          * @return bool
 368          */
 369         function forEachForeignRepo( $callback, $params = [] ) {
 370                 if ( !$this->reposInitialised ) {
 371                         $this->initialiseRepos();
 372                 }
 373                 foreach ( $this->foreignRepos as $repo ) {
 374                         $args = array_merge( [ $repo ], $params );
 375                         if ( call_user_func_array( $callback, $args ) ) {
 376                                 return true;
 377                         }
 378                 }
 379
 380                 return false;
 381         }
 382
 383         /**
 384          * Does the installation have any foreign repos set up?
 385          * @return bool
 386          */
 387         function hasForeignRepos() {
 388                 if ( !$this->reposInitialised ) {
 389                         $this->initialiseRepos();
 390                 }
 391                 return (bool)$this->foreignRepos;
 392         }
 393
 394         /**
 395          * Initialise the $repos array
 396          */
 397         function initialiseRepos() {
 398                 if ( $this->reposInitialised ) {
 399                         return;
 400                 }
 401                 $this->reposInitialised = true;
 402
 403                 $this->localRepo = $this->newRepo( $this->localInfo );
 404                 $this->foreignRepos = [];
 405                 foreach ( $this->foreignInfo as $key => $info ) {
 406                         $this->foreignRepos[$key] = $this->newRepo( $info );
 407                 }
 408         }
 409
 410         /**
 411          * Create a repo class based on an info structure
 412          * @param array $info
 413          * @return FileRepo
 414          */
 415         protected function newRepo( $info ) {
 416                 $class = $info['class'];
 417
 418                 return new $class( $info );
 419         }
 420
 421         /**
 422          * Split a virtual URL into repo, zone and rel parts
 423          * @param string $url
 424          * @throws MWException
 425          * @return array Containing repo, zone and rel
 426          */
 427         function splitVirtualUrl( $url ) {
 428                 if ( substr( $url, 0, 9 ) != 'mwrepo://' ) {
 429                         throw new MWException( __METHOD__ . ': unknown protocol' );
 430                 }
 431
 432                 $bits = explode( '/', substr( $url, 9 ), 3 );
 433                 if ( count( $bits ) != 3 ) {
 434                         throw new MWException( __METHOD__ . ": invalid mwrepo URL: $url" );
 435                 }
 436
 437                 return $bits;
 438         }
 439
 440         /**
 441          * @param string $fileName
 442          * @return array
 443          */
 444         function getFileProps( $fileName ) {
 445                 if ( FileRepo::isVirtualUrl( $fileName ) ) {
 446                         list( $repoName, /* $zone */, /* $rel */ ) = $this->splitVirtualUrl( $fileName );
 447                         if ( $repoName === '' ) {
 448                                 $repoName = 'local';
 449                         }
 450                         $repo = $this->getRepo( $repoName );
 451
 452                         return $repo->getFileProps( $fileName );
 453                 } else {
 454                         return FSFile::getPropsFromPath( $fileName );
 455                 }
 456         }
 457
 458         /**
 459          * Clear RepoGroup process cache used for finding a file
 460          * @param Title|null $title Title of the file or null to clear all files
 461          */
 462         public function clearCache( Title $title = null ) {
 463                 if ( $title == null ) {
 464                         $this->cache->clear();
 465                 } else {
 466                         $this->cache->clear( $title->getDBkey() );
 467                 }
 468         }
 469 }