includes/filerepo/backend/SwiftFileBackend.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup FileBackend
   5  * @author Russ Nelson
   6  * @author Aaron Schulz
   7  */
   8
   9 /**
  10  * @brief Class for an OpenStack Swift based file backend.
  11  *
  12  * This requires the SwiftCloudFiles MediaWiki extension, which includes
  13  * the php-cloudfiles library (https://github.com/rackspace/php-cloudfiles).
  14  * php-cloudfiles requires the curl, fileinfo, and mb_string PHP extensions.
  15  *
  16  * Status messages should avoid mentioning the Swift account name.
  17  * Likewise, error suppression should be used to avoid path disclosure.
  18  *
  19  * @ingroup FileBackend
  20  * @since 1.19
  21  */
  22 class SwiftFileBackend extends FileBackendStore {
  23         /** @var CF_Authentication */
  24         protected $auth; // Swift authentication handler
  25         protected $authTTL; // integer seconds
  26         protected $swiftAnonUser; // string; username to handle unauthenticated requests
  27         protected $maxContCacheSize = 100; // integer; max containers with entries
  28
  29         /** @var CF_Connection */
  30         protected $conn; // Swift connection handle
  31         protected $connStarted = 0; // integer UNIX timestamp
  32         protected $connContainers = array(); // container object cache
  33
  34         /**
  35          * @see FileBackendStore::__construct()
  36          * Additional $config params include:
  37          *    swiftAuthUrl       : Swift authentication server URL
  38          *    swiftUser          : Swift user used by MediaWiki (account:username)
  39          *    swiftKey           : Swift authentication key for the above user
  40          *    swiftAuthTTL       : Swift authentication TTL (seconds)
  41          *    swiftAnonUser      : Swift user used for end-user requests (account:username)
  42          *    shardViaHashLevels : Map of container names to sharding config with:
  43          *                         'base'   : base of hash characters, 16 or 36
  44          *                         'levels' : the number of hash levels (and digits)
  45          *                         'repeat' : hash subdirectories are prefixed with all the
  46          *                                    parent hash directory names (e.g. "a/ab/abc")
  47          */
  48         public function __construct( array $config ) {
  49                 parent::__construct( $config );
  50                 // Required settings
  51                 $this->auth = new CF_Authentication(
  52                         $config['swiftUser'],
  53                         $config['swiftKey'],
  54                         null, // account; unused
  55                         $config['swiftAuthUrl']
  56                 );
  57                 // Optional settings
  58                 $this->authTTL = isset( $config['swiftAuthTTL'] )
  59                         ? $config['swiftAuthTTL']
  60                         : 120; // some sane number
  61                 $this->swiftAnonUser = isset( $config['swiftAnonUser'] )
  62                         ? $config['swiftAnonUser']
  63                         : '';
  64                 $this->shardViaHashLevels = isset( $config['shardViaHashLevels'] )
  65                         ? $config['shardViaHashLevels']
  66                         : '';
  67         }
  68
  69         /**
  70          * @see FileBackendStore::resolveContainerPath()
  71          * @return null
  72          */
  73         protected function resolveContainerPath( $container, $relStoragePath ) {
  74                 if ( strlen( urlencode( $relStoragePath ) ) > 1024 ) {
  75                         return null; // too long for Swift
  76                 }
  77                 return $relStoragePath;
  78         }
  79
  80         /**
  81          * @see FileBackendStore::isPathUsableInternal()
  82          * @return bool
  83          */
  84         public function isPathUsableInternal( $storagePath ) {
  85                 list( $container, $rel ) = $this->resolveStoragePathReal( $storagePath );
  86                 if ( $rel === null ) {
  87                         return false; // invalid
  88                 }
  89
  90                 try {
  91                         $this->getContainer( $container );
  92                         return true; // container exists
  93                 } catch ( NoSuchContainerException $e ) {
  94                 } catch ( InvalidResponseException $e ) {
  95                 } catch ( Exception $e ) { // some other exception?
  96                         $this->logException( $e, __METHOD__, array( 'path' => $storagePath ) );
  97                 }
  98
  99                 return false;
 100         }
 101
 102         /**
 103          * @see FileBackendStore::doCreateInternal()
 104          * @return Status
 105          */
 106         protected function doCreateInternal( array $params ) {
 107                 $status = Status::newGood();
 108
 109                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 110                 if ( $dstRel === null ) {
 111                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 112                         return $status;
 113                 }
 114
 115                 // (a) Check the destination container and object
 116                 try {
 117                         $dContObj = $this->getContainer( $dstCont );
 118                         if ( empty( $params['overwrite'] ) &&
 119                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 120                         {
 121                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 122                                 return $status;
 123                         }
 124                 } catch ( NoSuchContainerException $e ) {
 125                         $status->fatal( 'backend-fail-create', $params['dst'] );
 126                         return $status;
 127                 } catch ( InvalidResponseException $e ) {
 128                         $status->fatal( 'backend-fail-connect', $this->name );
 129                         return $status;
 130                 } catch ( Exception $e ) { // some other exception?
 131                         $status->fatal( 'backend-fail-internal', $this->name );
 132                         $this->logException( $e, __METHOD__, $params );
 133                         return $status;
 134                 }
 135
 136                 // (b) Get a SHA-1 hash of the object
 137                 $sha1Hash = wfBaseConvert( sha1( $params['content'] ), 16, 36, 31 );
 138
 139                 // (c) Actually create the object
 140                 try {
 141                         // Create a fresh CF_Object with no fields preloaded.
 142                         // We don't want to preserve headers, metadata, and such.
 143                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 144                         // Note: metadata keys stored as [Upper case char][[Lower case char]...]
 145                         $obj->metadata = array( 'Sha1base36' => $sha1Hash );
 146                         // Manually set the ETag (https://github.com/rackspace/php-cloudfiles/issues/59).
 147                         // The MD5 here will be checked within Swift against its own MD5.
 148                         $obj->set_etag( md5( $params['content'] ) );
 149                         // Use the same content type as StreamFile for security
 150                         $obj->content_type = StreamFile::contentTypeFromPath( $params['dst'] );
 151                         // Actually write the object in Swift
 152                         $obj->write( $params['content'] );
 153                 } catch ( BadContentTypeException $e ) {
 154                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 155                 } catch ( InvalidResponseException $e ) {
 156                         $status->fatal( 'backend-fail-connect', $this->name );
 157                 } catch ( Exception $e ) { // some other exception?
 158                         $status->fatal( 'backend-fail-internal', $this->name );
 159                         $this->logException( $e, __METHOD__, $params );
 160                 }
 161
 162                 return $status;
 163         }
 164
 165         /**
 166          * @see FileBackendStore::doStoreInternal()
 167          * @return Status
 168          */
 169         protected function doStoreInternal( array $params ) {
 170                 $status = Status::newGood();
 171
 172                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 173                 if ( $dstRel === null ) {
 174                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 175                         return $status;
 176                 }
 177
 178                 // (a) Check the destination container and object
 179                 try {
 180                         $dContObj = $this->getContainer( $dstCont );
 181                         if ( empty( $params['overwrite'] ) &&
 182                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 183                         {
 184                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 185                                 return $status;
 186                         }
 187                 } catch ( NoSuchContainerException $e ) {
 188                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 189                         return $status;
 190                 } catch ( InvalidResponseException $e ) {
 191                         $status->fatal( 'backend-fail-connect', $this->name );
 192                         return $status;
 193                 } catch ( Exception $e ) { // some other exception?
 194                         $status->fatal( 'backend-fail-internal', $this->name );
 195                         $this->logException( $e, __METHOD__, $params );
 196                         return $status;
 197                 }
 198
 199                 // (b) Get a SHA-1 hash of the object
 200                 $sha1Hash = sha1_file( $params['src'] );
 201                 if ( $sha1Hash === false ) { // source doesn't exist?
 202                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 203                         return $status;
 204                 }
 205                 $sha1Hash = wfBaseConvert( $sha1Hash, 16, 36, 31 );
 206
 207                 // (c) Actually store the object
 208                 try {
 209                         // Create a fresh CF_Object with no fields preloaded.
 210                         // We don't want to preserve headers, metadata, and such.
 211                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 212                         // Note: metadata keys stored as [Upper case char][[Lower case char]...]
 213                         $obj->metadata = array( 'Sha1base36' => $sha1Hash );
 214                         // The MD5 here will be checked within Swift against its own MD5.
 215                         $obj->set_etag( md5_file( $params['src'] ) );
 216                         // Use the same content type as StreamFile for security
 217                         $obj->content_type = StreamFile::contentTypeFromPath( $params['dst'] );
 218                         // Actually write the object in Swift
 219                         $obj->load_from_filename( $params['src'], True ); // calls $obj->write()
 220                 } catch ( BadContentTypeException $e ) {
 221                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 222                 } catch ( IOException $e ) {
 223                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 224                 } catch ( InvalidResponseException $e ) {
 225                         $status->fatal( 'backend-fail-connect', $this->name );
 226                 } catch ( Exception $e ) { // some other exception?
 227                         $status->fatal( 'backend-fail-internal', $this->name );
 228                         $this->logException( $e, __METHOD__, $params );
 229                 }
 230
 231                 return $status;
 232         }
 233
 234         /**
 235          * @see FileBackendStore::doCopyInternal()
 236          * @return Status
 237          */
 238         protected function doCopyInternal( array $params ) {
 239                 $status = Status::newGood();
 240
 241                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 242                 if ( $srcRel === null ) {
 243                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 244                         return $status;
 245                 }
 246
 247                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 248                 if ( $dstRel === null ) {
 249                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 250                         return $status;
 251                 }
 252
 253                 // (a) Check the source/destination containers and destination object
 254                 try {
 255                         $sContObj = $this->getContainer( $srcCont );
 256                         $dContObj = $this->getContainer( $dstCont );
 257                         if ( empty( $params['overwrite'] ) &&
 258                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 259                         {
 260                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 261                                 return $status;
 262                         }
 263                 } catch ( NoSuchContainerException $e ) {
 264                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 265                         return $status;
 266                 } catch ( InvalidResponseException $e ) {
 267                         $status->fatal( 'backend-fail-connect', $this->name );
 268                         return $status;
 269                 } catch ( Exception $e ) { // some other exception?
 270                         $status->fatal( 'backend-fail-internal', $this->name );
 271                         $this->logException( $e, __METHOD__, $params );
 272                         return $status;
 273                 }
 274
 275                 // (b) Actually copy the file to the destination
 276                 try {
 277                         $sContObj->copy_object_to( $srcRel, $dContObj, $dstRel );
 278                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 279                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 280                 } catch ( InvalidResponseException $e ) {
 281                         $status->fatal( 'backend-fail-connect', $this->name );
 282                 } catch ( Exception $e ) { // some other exception?
 283                         $status->fatal( 'backend-fail-internal', $this->name );
 284                         $this->logException( $e, __METHOD__, $params );
 285                 }
 286
 287                 return $status;
 288         }
 289
 290         /**
 291          * @see FileBackendStore::doDeleteInternal()
 292          * @return Status
 293          */
 294         protected function doDeleteInternal( array $params ) {
 295                 $status = Status::newGood();
 296
 297                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 298                 if ( $srcRel === null ) {
 299                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 300                         return $status;
 301                 }
 302
 303                 try {
 304                         $sContObj = $this->getContainer( $srcCont );
 305                         $sContObj->delete_object( $srcRel );
 306                 } catch ( NoSuchContainerException $e ) {
 307                         $status->fatal( 'backend-fail-delete', $params['src'] );
 308                 } catch ( NoSuchObjectException $e ) {
 309                         if ( empty( $params['ignoreMissingSource'] ) ) {
 310                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 311                         }
 312                 } catch ( InvalidResponseException $e ) {
 313                         $status->fatal( 'backend-fail-connect', $this->name );
 314                 } catch ( Exception $e ) { // some other exception?
 315                         $status->fatal( 'backend-fail-internal', $this->name );
 316                         $this->logException( $e, __METHOD__, $params );
 317                 }
 318
 319                 return $status;
 320         }
 321
 322         /**
 323          * @see FileBackendStore::doPrepareInternal()
 324          * @return Status
 325          */
 326         protected function doPrepareInternal( $fullCont, $dir, array $params ) {
 327                 $status = Status::newGood();
 328
 329                 // (a) Check if container already exists
 330                 try {
 331                         $contObj = $this->getContainer( $fullCont );
 332                         // NoSuchContainerException not thrown: container must exist
 333                         return $status; // already exists
 334                 } catch ( NoSuchContainerException $e ) {
 335                         // NoSuchContainerException thrown: container does not exist
 336                 } catch ( InvalidResponseException $e ) {
 337                         $status->fatal( 'backend-fail-connect', $this->name );
 338                         return $status;
 339                 } catch ( Exception $e ) { // some other exception?
 340                         $status->fatal( 'backend-fail-internal', $this->name );
 341                         $this->logException( $e, __METHOD__, $params );
 342                         return $status;
 343                 }
 344
 345                 // (b) Create container as needed
 346                 try {
 347                         $contObj = $this->createContainer( $fullCont );
 348                         if ( $this->swiftAnonUser != '' ) {
 349                                 // Make container public to end-users...
 350                                 $status->merge( $this->setContainerAccess(
 351                                         $contObj,
 352                                         array( $this->auth->username, $this->swiftAnonUser ), // read
 353                                         array( $this->auth->username ) // write
 354                                 ) );
 355                         }
 356                 } catch ( InvalidResponseException $e ) {
 357                         $status->fatal( 'backend-fail-connect', $this->name );
 358                         return $status;
 359                 } catch ( Exception $e ) { // some other exception?
 360                         $status->fatal( 'backend-fail-internal', $this->name );
 361                         $this->logException( $e, __METHOD__, $params );
 362                         return $status;
 363                 }
 364
 365                 return $status;
 366         }
 367
 368         /**
 369          * @see FileBackendStore::doSecureInternal()
 370          * @return Status
 371          */
 372         protected function doSecureInternal( $fullCont, $dir, array $params ) {
 373                 $status = Status::newGood();
 374
 375                 if ( $this->swiftAnonUser != '' ) {
 376                         // Restrict container from end-users...
 377                         try {
 378                                 // doPrepareInternal() should have been called,
 379                                 // so the Swift container should already exist...
 380                                 $contObj = $this->getContainer( $fullCont ); // normally a cache hit
 381                                 // NoSuchContainerException not thrown: container must exist
 382                                 if ( !isset( $contObj->mw_wasSecured ) ) {
 383                                         $status->merge( $this->setContainerAccess(
 384                                                 $contObj,
 385                                                 array( $this->auth->username ), // read
 386                                                 array( $this->auth->username ) // write
 387                                         ) );
 388                                         // @TODO: when php-cloudfiles supports container
 389                                         // metadata, we can make use of that to avoid RTTs
 390                                         $contObj->mw_wasSecured = true; // avoid useless RTTs
 391                                 }
 392                         } catch ( InvalidResponseException $e ) {
 393                                 $status->fatal( 'backend-fail-connect', $this->name );
 394                         } catch ( Exception $e ) { // some other exception?
 395                                 $status->fatal( 'backend-fail-internal', $this->name );
 396                                 $this->logException( $e, __METHOD__, $params );
 397                         }
 398                 }
 399
 400                 return $status;
 401         }
 402
 403         /**
 404          * @see FileBackendStore::doCleanInternal()
 405          * @return Status
 406          */
 407         protected function doCleanInternal( $fullCont, $dir, array $params ) {
 408                 $status = Status::newGood();
 409
 410                 // Only containers themselves can be removed, all else is virtual
 411                 if ( $dir != '' ) {
 412                         return $status; // nothing to do
 413                 }
 414
 415                 // (a) Check the container
 416                 try {
 417                         $contObj = $this->getContainer( $fullCont, true );
 418                 } catch ( NoSuchContainerException $e ) {
 419                         return $status; // ok, nothing to do
 420                 } catch ( InvalidResponseException $e ) {
 421                         $status->fatal( 'backend-fail-connect', $this->name );
 422                         return $status;
 423                 } catch ( Exception $e ) { // some other exception?
 424                         $status->fatal( 'backend-fail-internal', $this->name );
 425                         $this->logException( $e, __METHOD__, $params );
 426                         return $status;
 427                 }
 428
 429                 // (b) Delete the container if empty
 430                 if ( $contObj->object_count == 0 ) {
 431                         try {
 432                                 $this->deleteContainer( $fullCont );
 433                         } catch ( NoSuchContainerException $e ) {
 434                                 return $status; // race?
 435                         } catch ( InvalidResponseException $e ) {
 436                                 $status->fatal( 'backend-fail-connect', $this->name );
 437                                 return $status;
 438                         } catch ( Exception $e ) { // some other exception?
 439                                 $status->fatal( 'backend-fail-internal', $this->name );
 440                                 $this->logException( $e, __METHOD__, $params );
 441                                 return $status;
 442                         }
 443                 }
 444
 445                 return $status;
 446         }
 447
 448         /**
 449          * @see FileBackendStore::doFileExists()
 450          * @return array|bool|null
 451          */
 452         protected function doGetFileStat( array $params ) {
 453                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 454                 if ( $srcRel === null ) {
 455                         return false; // invalid storage path
 456                 }
 457
 458                 $stat = false;
 459                 try {
 460                         $contObj = $this->getContainer( $srcCont );
 461                         $srcObj = $contObj->get_object( $srcRel, $this->headersFromParams( $params ) );
 462                         $this->addMissingMetadata( $srcObj, $params['src'] );
 463                         $stat = array(
 464                                 // Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT" to TS_MW
 465                                 'mtime' => wfTimestamp( TS_MW, $srcObj->last_modified ),
 466                                 'size'  => $srcObj->content_length,
 467                                 'sha1'  => $srcObj->metadata['Sha1base36']
 468                         );
 469                 } catch ( NoSuchContainerException $e ) {
 470                 } catch ( NoSuchObjectException $e ) {
 471                 } catch ( InvalidResponseException $e ) {
 472                         $stat = null;
 473                 } catch ( Exception $e ) { // some other exception?
 474                         $stat = null;
 475                         $this->logException( $e, __METHOD__, $params );
 476                 }
 477
 478                 return $stat;
 479         }
 480
 481         /**
 482          * Fill in any missing object metadata and save it to Swift
 483          *
 484          * @param $obj CF_Object
 485          * @param $path string Storage path to object
 486          * @return bool Success
 487          * @throws Exception cloudfiles exceptions
 488          */
 489         protected function addMissingMetadata( CF_Object $obj, $path ) {
 490                 if ( isset( $obj->metadata['Sha1base36'] ) ) {
 491                         return true; // nothing to do
 492                 }
 493                 $status = Status::newGood();
 494                 $scopeLockS = $this->getScopedFileLocks( array( $path ), LockManager::LOCK_UW, $status );
 495                 if ( $status->isOK() ) {
 496                         $tmpFile = $this->getLocalCopy( array( 'src' => $path, 'latest' => 1 ) );
 497                         if ( $tmpFile ) {
 498                                 $hash = $tmpFile->getSha1Base36();
 499                                 if ( $hash !== false ) {
 500                                         $obj->metadata['Sha1base36'] = $hash;
 501                                         $obj->sync_metadata(); // save to Swift
 502                                         return true; // success
 503                                 }
 504                         }
 505                 }
 506                 $obj->metadata['Sha1base36'] = false;
 507                 return false; // failed
 508         }
 509
 510         /**
 511          * @see FileBackend::getFileContents()
 512          * @return bool|null|string
 513          */
 514         public function getFileContents( array $params ) {
 515                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 516                 if ( $srcRel === null ) {
 517                         return false; // invalid storage path
 518                 }
 519
 520                 if ( !$this->fileExists( $params ) ) {
 521                         return null;
 522                 }
 523
 524                 $data = false;
 525                 try {
 526                         $sContObj = $this->getContainer( $srcCont );
 527                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD request
 528                         $data = $obj->read( $this->headersFromParams( $params ) );
 529                 } catch ( NoSuchContainerException $e ) {
 530                 } catch ( InvalidResponseException $e ) {
 531                 } catch ( Exception $e ) { // some other exception?
 532                         $this->logException( $e, __METHOD__, $params );
 533                 }
 534
 535                 return $data;
 536         }
 537
 538         /**
 539          * @see FileBackendStore::getFileListInternal()
 540          * @return SwiftFileBackendFileList
 541          */
 542         public function getFileListInternal( $fullCont, $dir, array $params ) {
 543                 return new SwiftFileBackendFileList( $this, $fullCont, $dir );
 544         }
 545
 546         /**
 547          * Do not call this function outside of SwiftFileBackendFileList
 548          *
 549          * @param $fullCont string Resolved container name
 550          * @param $dir string Resolved storage directory with no trailing slash
 551          * @param $after string Storage path of file to list items after
 552          * @param $limit integer Max number of items to list
 553          * @return Array
 554          */
 555         public function getFileListPageInternal( $fullCont, $dir, $after, $limit ) {
 556                 $files = array();
 557
 558                 try {
 559                         $container = $this->getContainer( $fullCont );
 560                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
 561                         $files = $container->list_objects( $limit, $after, $prefix );
 562                 } catch ( NoSuchContainerException $e ) {
 563                 } catch ( InvalidResponseException $e ) {
 564                 } catch ( Exception $e ) { // some other exception?
 565                         $this->logException( $e, __METHOD__, array( 'cont' => $fullCont, 'dir' => $dir ) );
 566                 }
 567
 568                 return $files;
 569         }
 570
 571         /**
 572          * @see FileBackendStore::doGetFileSha1base36()
 573          * @return bool
 574          */
 575         protected function doGetFileSha1base36( array $params ) {
 576                 $stat = $this->getFileStat( $params );
 577                 if ( $stat ) {
 578                         return $stat['sha1'];
 579                 } else {
 580                         return false;
 581                 }
 582         }
 583
 584         /**
 585          * @see FileBackendStore::doStreamFile()
 586          * @return Status
 587          */
 588         protected function doStreamFile( array $params ) {
 589                 $status = Status::newGood();
 590
 591                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 592                 if ( $srcRel === null ) {
 593                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 594                 }
 595
 596                 try {
 597                         $cont = $this->getContainer( $srcCont );
 598                 } catch ( NoSuchContainerException $e ) {
 599                         $status->fatal( 'backend-fail-stream', $params['src'] );
 600                         return $status;
 601                 } catch ( InvalidResponseException $e ) {
 602                         $status->fatal( 'backend-fail-connect', $this->name );
 603                         return $status;
 604                 } catch ( Exception $e ) { // some other exception?
 605                         $status->fatal( 'backend-fail-stream', $params['src'] );
 606                         $this->logException( $e, __METHOD__, $params );
 607                         return $status;
 608                 }
 609
 610                 try {
 611                         $output = fopen( 'php://output', 'wb' );
 612                         $obj = new CF_Object( $cont, $srcRel, false, false ); // skip HEAD request
 613                         $obj->stream( $output, $this->headersFromParams( $params ) );
 614                 } catch ( InvalidResponseException $e ) { // 404? connection problem?
 615                         $status->fatal( 'backend-fail-stream', $params['src'] );
 616                 } catch ( Exception $e ) { // some other exception?
 617                         $status->fatal( 'backend-fail-stream', $params['src'] );
 618                         $this->logException( $e, __METHOD__, $params );
 619                 }
 620
 621                 return $status;
 622         }
 623
 624         /**
 625          * @see FileBackendStore::getLocalCopy()
 626          * @return null|TempFSFile
 627          */
 628         public function getLocalCopy( array $params ) {
 629                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 630                 if ( $srcRel === null ) {
 631                         return null;
 632                 }
 633
 634                 if ( !$this->fileExists( $params ) ) {
 635                         return null;
 636                 }
 637
 638                 $tmpFile = null;
 639                 try {
 640                         $sContObj = $this->getContainer( $srcCont );
 641                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 642                         // Get source file extension
 643                         $ext = FileBackend::extensionFromPath( $srcRel );
 644                         // Create a new temporary file...
 645                         $tmpFile = TempFSFile::factory( wfBaseName( $srcRel ) . '_', $ext );
 646                         if ( $tmpFile ) {
 647                                 $handle = fopen( $tmpFile->getPath(), 'wb' );
 648                                 if ( $handle ) {
 649                                         $obj->stream( $handle, $this->headersFromParams( $params ) );
 650                                         fclose( $handle );
 651                                 } else {
 652                                         $tmpFile = null; // couldn't open temp file
 653                                 }
 654                         }
 655                 } catch ( NoSuchContainerException $e ) {
 656                         $tmpFile = null;
 657                 } catch ( InvalidResponseException $e ) {
 658                         $tmpFile = null;
 659                 } catch ( Exception $e ) { // some other exception?
 660                         $tmpFile = null;
 661                         $this->logException( $e, __METHOD__, $params );
 662                 }
 663
 664                 return $tmpFile;
 665         }
 666
 667         /**
 668          * Get headers to send to Swift when reading a file based
 669          * on a FileBackend params array, e.g. that of getLocalCopy().
 670          * $params is currently only checked for a 'latest' flag.
 671          *
 672          * @param $params Array
 673          * @return Array
 674          */
 675         protected function headersFromParams( array $params ) {
 676                 $hdrs = array();
 677                 if ( !empty( $params['latest'] ) ) {
 678                         $hdrs[] = 'X-Newest: true';
 679                 }
 680                 return $hdrs;
 681         }
 682
 683         /**
 684          * Set read/write permissions for a Swift container
 685          *
 686          * @param $contObj CF_Container Swift container
 687          * @param $readGrps Array Swift users who can read (account:user)
 688          * @param $writeGrps Array Swift users who can write (account:user)
 689          * @return Status
 690          */
 691         protected function setContainerAccess(
 692                 CF_Container $contObj, array $readGrps, array $writeGrps
 693         ) {
 694                 $creds = $contObj->cfs_auth->export_credentials();
 695
 696                 $url = $creds['storage_url'] . '/' . rawurlencode( $contObj->name );
 697
 698                 // Note: 10 second timeout consistent with php-cloudfiles
 699                 $req = new CurlHttpRequest( $url, array( 'method' => 'POST', 'timeout' => 10 ) );
 700                 $req->setHeader( 'X-Auth-Token', $creds['auth_token'] );
 701                 $req->setHeader( 'X-Container-Read', implode( ',', $readGrps ) );
 702                 $req->setHeader( 'X-Container-Write', implode( ',', $writeGrps ) );
 703
 704                 return $req->execute(); // should return 204
 705         }
 706
 707         /**
 708          * Get a connection to the Swift proxy
 709          *
 710          * @return CF_Connection|bool False on failure
 711          * @throws InvalidResponseException
 712          */
 713         protected function getConnection() {
 714                 if ( $this->conn === false ) {
 715                         throw new InvalidResponseException; // failed last attempt
 716                 }
 717                 // Session keys expire after a while, so we renew them periodically
 718                 if ( $this->conn && ( time() - $this->connStarted ) > $this->authTTL ) {
 719                         $this->conn->close(); // close active cURL connections
 720                         $this->conn = null;
 721                 }
 722                 // Authenticate with proxy and get a session key...
 723                 if ( $this->conn === null ) {
 724                         $this->connContainers = array();
 725                         try {
 726                                 $this->auth->authenticate();
 727                                 $this->conn = new CF_Connection( $this->auth );
 728                                 $this->connStarted = time();
 729                         } catch ( AuthenticationException $e ) {
 730                                 $this->conn = false; // don't keep re-trying
 731                         } catch ( InvalidResponseException $e ) {
 732                                 $this->conn = false; // don't keep re-trying
 733                         }
 734                 }
 735                 if ( !$this->conn ) {
 736                         throw new InvalidResponseException; // auth/connection problem
 737                 }
 738                 return $this->conn;
 739         }
 740
 741         /**
 742          * @see FileBackendStore::doClearCache()
 743          */
 744         protected function doClearCache( array $paths = null ) {
 745                 $this->connContainers = array(); // clear container object cache
 746         }
 747
 748         /**
 749          * Get a Swift container object, possibly from process cache.
 750          * Use $reCache if the file count or byte count is needed.
 751          *
 752          * @param $container string Container name
 753          * @param $reCache bool Refresh the process cache
 754          * @return CF_Container
 755          */
 756         protected function getContainer( $container, $reCache = false ) {
 757                 $conn = $this->getConnection(); // Swift proxy connection
 758                 if ( $reCache ) {
 759                         unset( $this->connContainers[$container] ); // purge cache
 760                 }
 761                 if ( !isset( $this->connContainers[$container] ) ) {
 762                         $contObj = $conn->get_container( $container );
 763                         // NoSuchContainerException not thrown: container must exist
 764                         if ( count( $this->connContainers ) >= $this->maxContCacheSize ) { // trim cache?
 765                                 reset( $this->connContainers );
 766                                 $key = key( $this->connContainers );
 767                                 unset( $this->connContainers[$key] );
 768                         }
 769                         $this->connContainers[$container] = $contObj; // cache it
 770                 }
 771                 return $this->connContainers[$container];
 772         }
 773
 774         /**
 775          * Create a Swift container
 776          *
 777          * @param $container string Container name
 778          * @return CF_Container
 779          */
 780         protected function createContainer( $container ) {
 781                 $conn = $this->getConnection(); // Swift proxy connection
 782                 $contObj = $conn->create_container( $container );
 783                 $this->connContainers[$container] = $contObj; // cache it
 784                 return $contObj;
 785         }
 786
 787         /**
 788          * Delete a Swift container
 789          *
 790          * @param $container string Container name
 791          * @return void
 792          */
 793         protected function deleteContainer( $container ) {
 794                 $conn = $this->getConnection(); // Swift proxy connection
 795                 $conn->delete_container( $container );
 796                 unset( $this->connContainers[$container] ); // purge cache
 797         }
 798
 799         /**
 800          * Log an unexpected exception for this backend
 801          *
 802          * @param $e Exception
 803          * @param $func string
 804          * @param $params Array
 805          * @return void
 806          */
 807         protected function logException( Exception $e, $func, array $params ) {
 808                 wfDebugLog( 'SwiftBackend',
 809                         get_class( $e ) . " in '{$func}' (given '" . FormatJson::encode( $params ) . "')" .
 810                         ( $e instanceof InvalidResponseException
 811                                 ? ": {$e->getMessage()}"
 812                                 : ""
 813                         )
 814                 );
 815         }
 816 }
 817
 818 /**
 819  * SwiftFileBackend helper class to page through object listings.
 820  * Swift also has a listing limit of 10,000 objects for sanity.
 821  * Do not use this class from places outside SwiftFileBackend.
 822  *
 823  * @ingroup FileBackend
 824  */
 825 class SwiftFileBackendFileList implements Iterator {
 826         /** @var Array */
 827         protected $bufferIter = array();
 828         protected $bufferAfter = null; // string; list items *after* this path
 829         protected $pos = 0; // integer
 830
 831         /** @var SwiftFileBackend */
 832         protected $backend;
 833         protected $container; //
 834         protected $dir; // string storage directory
 835         protected $suffixStart; // integer
 836
 837         const PAGE_SIZE = 5000; // file listing buffer size
 838
 839         /**
 840          * @param $backend SwiftFileBackend
 841          * @param $fullCont string Resolved container name
 842          * @param $dir string Resolved directory relative to container
 843          */
 844         public function __construct( SwiftFileBackend $backend, $fullCont, $dir ) {
 845                 $this->backend = $backend;
 846                 $this->container = $fullCont;
 847                 $this->dir = $dir;
 848                 if ( substr( $this->dir, -1 ) === '/' ) {
 849                         $this->dir = substr( $this->dir, 0, -1 ); // remove trailing slash
 850                 }
 851                 if ( $this->dir == '' ) { // whole container
 852                         $this->suffixStart = 0;
 853                 } else { // dir within container
 854                         $this->suffixStart = strlen( $this->dir ) + 1; // size of "path/to/dir/"
 855                 }
 856         }
 857
 858         /**
 859          * @see Iterator::current()
 860          * @return string|bool String or false
 861          */
 862         public function current() {
 863                 return substr( current( $this->bufferIter ), $this->suffixStart );
 864         }
 865
 866         /**
 867          * @see Iterator::key()
 868          * @return integer
 869          */
 870         public function key() {
 871                 return $this->pos;
 872         }
 873
 874         /**
 875          * @see Iterator::next()
 876          * @return void
 877          */
 878         public function next() {
 879                 // Advance to the next file in the page
 880                 next( $this->bufferIter );
 881                 ++$this->pos;
 882                 // Check if there are no files left in this page and
 883                 // advance to the next page if this page was not empty.
 884                 if ( !$this->valid() && count( $this->bufferIter ) ) {
 885                         $this->bufferAfter = end( $this->bufferIter );
 886                         $this->bufferIter = $this->backend->getFileListPageInternal(
 887                                 $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE
 888                         );
 889                 }
 890         }
 891
 892         /**
 893          * @see Iterator::rewind()
 894          * @return void
 895          */
 896         public function rewind() {
 897                 $this->pos = 0;
 898                 $this->bufferAfter = null;
 899                 $this->bufferIter = $this->backend->getFileListPageInternal(
 900                         $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE
 901                 );
 902         }
 903
 904         /**
 905          * @see Iterator::valid()
 906          * @return bool
 907          */
 908         public function valid() {
 909                 return ( current( $this->bufferIter ) !== false ); // no paths can have this value
 910         }
 911 }