includes/filebackend/SwiftFileBackend.php

   1 <?php
   2 /**
   3  * OpenStack Swift based file backend.
   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 FileBackend
  22  * @author Russ Nelson
  23  * @author Aaron Schulz
  24  */
  25
  26 /**
  27  * @brief Class for an OpenStack Swift (or Ceph RGW) based file backend.
  28  *
  29  * This requires the SwiftCloudFiles MediaWiki extension, which includes
  30  * the php-cloudfiles library (https://github.com/rackspace/php-cloudfiles).
  31  * php-cloudfiles requires the curl, fileinfo, and mb_string PHP extensions.
  32  *
  33  * Status messages should avoid mentioning the Swift account name.
  34  * Likewise, error suppression should be used to avoid path disclosure.
  35  *
  36  * @ingroup FileBackend
  37  * @since 1.19
  38  */
  39 class SwiftFileBackend extends FileBackendStore {
  40         /** @var CF_Authentication Swift authentication handler */
  41         protected $auth;
  42
  43         /** @var int TTL in seconds */
  44         protected $authTTL;
  45
  46         /** @var string Shared secret value for making temp URLs */
  47         protected $swiftTempUrlKey;
  48
  49         /** @var string Username to handle unauthenticated requests */
  50         protected $swiftAnonUser;
  51
  52         /** @var bool Whether CloudFiles CDN is enabled */
  53         protected $swiftUseCDN;
  54
  55         /** @var int How long to cache things in the CDN */
  56         protected $swiftCDNExpiry;
  57
  58         /** @var bool Whether object CDN purging is enabled */
  59         protected $swiftCDNPurgable;
  60
  61         // Rados Gateway specific options
  62         /** @var string S3 access key */
  63         protected $rgwS3AccessKey;
  64
  65         /** @var string S3 authentication key */
  66         protected $rgwS3SecretKey;
  67
  68         /** @var CF_Connection Swift connection handle*/
  69         protected $conn;
  70
  71         /** @var int UNIX timestamp */
  72         protected $sessionStarted = 0;
  73
  74         /** @var CloudFilesException */
  75         protected $connException;
  76
  77         /** @var int UNIX timestamp */
  78         protected $connErrorTime = 0;
  79
  80         /** @var BagOStuff */
  81         protected $srvCache;
  82
  83         /** @var ProcessCacheLRU */
  84         protected $connContainerCache; // container object cache
  85
  86         /**
  87          * @see FileBackendStore::__construct()
  88          * Additional $config params include:
  89          *   - swiftAuthUrl       : Swift authentication server URL
  90          *   - swiftUser          : Swift user used by MediaWiki (account:username)
  91          *   - swiftKey           : Swift authentication key for the above user
  92          *   - swiftAuthTTL       : Swift authentication TTL (seconds)
  93          *   - swiftTempUrlKey    : Swift "X-Account-Meta-Temp-URL-Key" value on the account.
  94          *                          Do not set this until it has been set in the backend.
  95          *   - swiftAnonUser      : Swift user used for end-user requests (account:username).
  96          *                          If set, then views of public containers are assumed to go
  97          *                          through this user. If not set, then public containers are
  98          *                          accessible to unauthenticated requests via ".r:*" in the ACL.
  99          *   - swiftUseCDN        : Whether a Cloud Files Content Delivery Network is set up
 100          *   - swiftCDNExpiry     : How long (in seconds) to store content in the CDN.
 101          *                          If files may likely change, this should probably not exceed
 102          *                          a few days. For example, deletions may take this long to apply.
 103          *                          If object purging is enabled, however, this is not an issue.
 104          *   - swiftCDNPurgable   : Whether object purge requests are allowed by the CDN.
 105          *   - shardViaHashLevels : Map of container names to sharding config with:
 106          *                             - base   : base of hash characters, 16 or 36
 107          *                             - levels : the number of hash levels (and digits)
 108          *                             - repeat : hash subdirectories are prefixed with all the
 109          *                                        parent hash directory names (e.g. "a/ab/abc")
 110          *   - cacheAuthInfo      : Whether to cache authentication tokens in APC, XCache, ect.
 111          *                          If those are not available, then the main cache will be used.
 112          *                          This is probably insecure in shared hosting environments.
 113          *   - rgwS3AccessKey     : Ragos Gateway S3 "access key" value on the account.
 114          *                          Do not set this until it has been set in the backend.
 115          *                          This is used for generating expiring pre-authenticated URLs.
 116          *                          Only use this when using rgw and to work around
 117          *                          http://tracker.newdream.net/issues/3454.
 118          *   - rgwS3SecretKey     : Ragos Gateway S3 "secret key" value on the account.
 119          *                          Do not set this until it has been set in the backend.
 120          *                          This is used for generating expiring pre-authenticated URLs.
 121          *                          Only use this when using rgw and to work around
 122          *                          http://tracker.newdream.net/issues/3454.
 123          */
 124         public function __construct( array $config ) {
 125                 parent::__construct( $config );
 126                 if ( !class_exists( 'CF_Constants' ) ) {
 127                         throw new FileBackendException( 'SwiftCloudFiles extension not installed.' );
 128                 }
 129                 // Required settings
 130                 $this->auth = new CF_Authentication(
 131                         $config['swiftUser'],
 132                         $config['swiftKey'],
 133                         null, // account; unused
 134                         $config['swiftAuthUrl']
 135                 );
 136                 // Optional settings
 137                 $this->authTTL = isset( $config['swiftAuthTTL'] )
 138                         ? $config['swiftAuthTTL']
 139                         : 5 * 60; // some sane number
 140                 $this->swiftAnonUser = isset( $config['swiftAnonUser'] )
 141                         ? $config['swiftAnonUser']
 142                         : '';
 143                 $this->swiftTempUrlKey = isset( $config['swiftTempUrlKey'] )
 144                         ? $config['swiftTempUrlKey']
 145                         : '';
 146                 $this->shardViaHashLevels = isset( $config['shardViaHashLevels'] )
 147                         ? $config['shardViaHashLevels']
 148                         : '';
 149                 $this->swiftUseCDN = isset( $config['swiftUseCDN'] )
 150                         ? $config['swiftUseCDN']
 151                         : false;
 152                 $this->swiftCDNExpiry = isset( $config['swiftCDNExpiry'] )
 153                         ? $config['swiftCDNExpiry']
 154                         : 12 * 3600; // 12 hours is safe (tokens last 24 hours per http://docs.openstack.org)
 155                 $this->swiftCDNPurgable = isset( $config['swiftCDNPurgable'] )
 156                         ? $config['swiftCDNPurgable']
 157                         : true;
 158                 $this->rgwS3AccessKey = isset( $config['rgwS3AccessKey'] )
 159                         ? $config['rgwS3AccessKey']
 160                         : '';
 161                 $this->rgwS3SecretKey = isset( $config['rgwS3SecretKey'] )
 162                         ? $config['rgwS3SecretKey']
 163                         : '';
 164                 // Cache container information to mask latency
 165                 $this->memCache = wfGetMainCache();
 166                 // Process cache for container info
 167                 $this->connContainerCache = new ProcessCacheLRU( 300 );
 168                 // Cache auth token information to avoid RTTs
 169                 if ( !empty( $config['cacheAuthInfo'] ) ) {
 170                         if ( PHP_SAPI === 'cli' ) {
 171                                 $this->srvCache = wfGetMainCache(); // preferrably memcached
 172                         } else {
 173                                 try { // look for APC, XCache, WinCache, ect...
 174                                         $this->srvCache = ObjectCache::newAccelerator( array() );
 175                                 } catch ( Exception $e ) {
 176                                 }
 177                         }
 178                 }
 179                 $this->srvCache = $this->srvCache ? $this->srvCache : new EmptyBagOStuff();
 180         }
 181
 182         /**
 183          * @see FileBackendStore::resolveContainerPath()
 184          * @param string $container
 185          * @param string $relStoragePath
 186          * @return string|null Returns null when the URL encoded storage path is
 187          *   longer than 1024 characters or not UTF-8 encoded.
 188          */
 189         protected function resolveContainerPath( $container, $relStoragePath ) {
 190                 if ( !mb_check_encoding( $relStoragePath, 'UTF-8' ) ) { // mb_string required by CF
 191                         return null; // not UTF-8, makes it hard to use CF and the swift HTTP API
 192                 } elseif ( strlen( urlencode( $relStoragePath ) ) > 1024 ) {
 193                         return null; // too long for Swift
 194                 }
 195
 196                 return $relStoragePath;
 197         }
 198
 199         public function isPathUsableInternal( $storagePath ) {
 200                 list( $container, $rel ) = $this->resolveStoragePathReal( $storagePath );
 201                 if ( $rel === null ) {
 202                         return false; // invalid
 203                 }
 204
 205                 try {
 206                         $this->getContainer( $container );
 207
 208                         return true; // container exists
 209                 } catch ( NoSuchContainerException $e ) {
 210                 } catch ( CloudFilesException $e ) { // some other exception?
 211                         $this->handleException( $e, null, __METHOD__, array( 'path' => $storagePath ) );
 212                 }
 213
 214                 return false;
 215         }
 216
 217         /**
 218          * @param array $headers
 219          * @return array
 220          */
 221         protected function sanitizeHdrs( array $headers ) {
 222                 // By default, Swift has annoyingly low maximum header value limits
 223                 if ( isset( $headers['Content-Disposition'] ) ) {
 224                         $headers['Content-Disposition'] = $this->truncDisp( $headers['Content-Disposition'] );
 225                 }
 226
 227                 return $headers;
 228         }
 229
 230         /**
 231          * @param string $disposition Content-Disposition header value
 232          * @return string Truncated Content-Disposition header value to meet Swift limits
 233          */
 234         protected function truncDisp( $disposition ) {
 235                 $res = '';
 236                 foreach ( explode( ';', $disposition ) as $part ) {
 237                         $part = trim( $part );
 238                         $new = ( $res === '' ) ? $part : "{$res};{$part}";
 239                         if ( strlen( $new ) <= 255 ) {
 240                                 $res = $new;
 241                         } else {
 242                                 break; // too long; sigh
 243                         }
 244                 }
 245
 246                 return $res;
 247         }
 248
 249         protected function doCreateInternal( array $params ) {
 250                 $status = Status::newGood();
 251
 252                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 253                 if ( $dstRel === null ) {
 254                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 255
 256                         return $status;
 257                 }
 258
 259                 // (a) Check the destination container and object
 260                 try {
 261                         $dContObj = $this->getContainer( $dstCont );
 262                 } catch ( NoSuchContainerException $e ) {
 263                         $status->fatal( 'backend-fail-create', $params['dst'] );
 264
 265                         return $status;
 266                 } catch ( CloudFilesException $e ) { // some other exception?
 267                         $this->handleException( $e, $status, __METHOD__, $params );
 268
 269                         return $status;
 270                 }
 271
 272                 // (b) Get a SHA-1 hash of the object
 273                 $sha1Hash = wfBaseConvert( sha1( $params['content'] ), 16, 36, 31 );
 274
 275                 // (c) Actually create the object
 276                 try {
 277                         // Create a fresh CF_Object with no fields preloaded.
 278                         // We don't want to preserve headers, metadata, and such.
 279                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 280                         $obj->setMetadataValues( array( 'Sha1base36' => $sha1Hash ) );
 281                         // Manually set the ETag (https://github.com/rackspace/php-cloudfiles/issues/59).
 282                         // The MD5 here will be checked within Swift against its own MD5.
 283                         $obj->set_etag( md5( $params['content'] ) );
 284                         // Use the same content type as StreamFile for security
 285                         $obj->content_type = $this->getContentType( $params['dst'], $params['content'], null );
 286                         // Set any other custom headers if requested
 287                         if ( isset( $params['headers'] ) ) {
 288                                 $obj->headers += $this->sanitizeHdrs( $params['headers'] );
 289                         }
 290                         if ( !empty( $params['async'] ) ) { // deferred
 291                                 $op = $obj->write_async( $params['content'] );
 292                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Create', $op );
 293                                 $status->value->affectedObjects[] = $obj;
 294                         } else { // actually write the object in Swift
 295                                 $obj->write( $params['content'] );
 296                                 $this->purgeCDNCache( array( $obj ) );
 297                         }
 298                 } catch ( CDNNotEnabledException $e ) {
 299                         // CDN not enabled; nothing to see here
 300                 } catch ( BadContentTypeException $e ) {
 301                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 302                 } catch ( CloudFilesException $e ) { // some other exception?
 303                         $this->handleException( $e, $status, __METHOD__, $params );
 304                 }
 305
 306                 return $status;
 307         }
 308
 309         /**
 310          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 311          */
 312         protected function getResponseCreate( CF_Async_Op $cfOp, Status $status, array $params ) {
 313                 try {
 314                         $cfOp->getLastResponse();
 315                 } catch ( BadContentTypeException $e ) {
 316                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 317                 }
 318         }
 319
 320         protected function doStoreInternal( array $params ) {
 321                 $status = Status::newGood();
 322
 323                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 324                 if ( $dstRel === null ) {
 325                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 326
 327                         return $status;
 328                 }
 329
 330                 // (a) Check the destination container and object
 331                 try {
 332                         $dContObj = $this->getContainer( $dstCont );
 333                 } catch ( NoSuchContainerException $e ) {
 334                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 335
 336                         return $status;
 337                 } catch ( CloudFilesException $e ) { // some other exception?
 338                         $this->handleException( $e, $status, __METHOD__, $params );
 339
 340                         return $status;
 341                 }
 342
 343                 // (b) Get a SHA-1 hash of the object
 344                 wfSuppressWarnings();
 345                 $sha1Hash = sha1_file( $params['src'] );
 346                 wfRestoreWarnings();
 347                 if ( $sha1Hash === false ) { // source doesn't exist?
 348                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 349
 350                         return $status;
 351                 }
 352                 $sha1Hash = wfBaseConvert( $sha1Hash, 16, 36, 31 );
 353
 354                 // (c) Actually store the object
 355                 try {
 356                         // Create a fresh CF_Object with no fields preloaded.
 357                         // We don't want to preserve headers, metadata, and such.
 358                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 359                         $obj->setMetadataValues( array( 'Sha1base36' => $sha1Hash ) );
 360                         // The MD5 here will be checked within Swift against its own MD5.
 361                         $obj->set_etag( md5_file( $params['src'] ) );
 362                         // Use the same content type as StreamFile for security
 363                         $obj->content_type = $this->getContentType( $params['dst'], null, $params['src'] );
 364                         // Set any other custom headers if requested
 365                         if ( isset( $params['headers'] ) ) {
 366                                 $obj->headers += $this->sanitizeHdrs( $params['headers'] );
 367                         }
 368                         if ( !empty( $params['async'] ) ) { // deferred
 369                                 wfSuppressWarnings();
 370                                 $fp = fopen( $params['src'], 'rb' );
 371                                 wfRestoreWarnings();
 372                                 if ( !$fp ) {
 373                                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 374                                 } else {
 375                                         $op = $obj->write_async( $fp, filesize( $params['src'] ), true );
 376                                         $status->value = new SwiftFileOpHandle( $this, $params, 'Store', $op );
 377                                         $status->value->resourcesToClose[] = $fp;
 378                                         $status->value->affectedObjects[] = $obj;
 379                                 }
 380                         } else { // actually write the object in Swift
 381                                 $obj->load_from_filename( $params['src'], true ); // calls $obj->write()
 382                                 $this->purgeCDNCache( array( $obj ) );
 383                         }
 384                 } catch ( CDNNotEnabledException $e ) {
 385                         // CDN not enabled; nothing to see here
 386                 } catch ( BadContentTypeException $e ) {
 387                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 388                 } catch ( IOException $e ) {
 389                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 390                 } catch ( CloudFilesException $e ) { // some other exception?
 391                         $this->handleException( $e, $status, __METHOD__, $params );
 392                 }
 393
 394                 return $status;
 395         }
 396
 397         /**
 398          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 399          */
 400         protected function getResponseStore( CF_Async_Op $cfOp, Status $status, array $params ) {
 401                 try {
 402                         $cfOp->getLastResponse();
 403                 } catch ( BadContentTypeException $e ) {
 404                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 405                 } catch ( IOException $e ) {
 406                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 407                 }
 408         }
 409
 410         protected function doCopyInternal( array $params ) {
 411                 $status = Status::newGood();
 412
 413                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 414                 if ( $srcRel === null ) {
 415                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 416
 417                         return $status;
 418                 }
 419
 420                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 421                 if ( $dstRel === null ) {
 422                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 423
 424                         return $status;
 425                 }
 426
 427                 // (a) Check the source/destination containers and destination object
 428                 try {
 429                         $sContObj = $this->getContainer( $srcCont );
 430                         $dContObj = $this->getContainer( $dstCont );
 431                 } catch ( NoSuchContainerException $e ) {
 432                         if ( empty( $params['ignoreMissingSource'] ) || isset( $sContObj ) ) {
 433                                 $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 434                         }
 435
 436                         return $status;
 437                 } catch ( CloudFilesException $e ) { // some other exception?
 438                         $this->handleException( $e, $status, __METHOD__, $params );
 439
 440                         return $status;
 441                 }
 442
 443                 // (b) Actually copy the file to the destination
 444                 try {
 445                         $dstObj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 446                         $hdrs = array(); // source file headers to override with new values
 447                         // Set any other custom headers if requested
 448                         if ( isset( $params['headers'] ) ) {
 449                                 $hdrs += $this->sanitizeHdrs( $params['headers'] );
 450                         }
 451                         if ( !empty( $params['async'] ) ) { // deferred
 452                                 $op = $sContObj->copy_object_to_async( $srcRel, $dContObj, $dstRel, null, $hdrs );
 453                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Copy', $op );
 454                                 $status->value->affectedObjects[] = $dstObj;
 455                         } else { // actually write the object in Swift
 456                                 $sContObj->copy_object_to( $srcRel, $dContObj, $dstRel, null, $hdrs );
 457                                 $this->purgeCDNCache( array( $dstObj ) );
 458                         }
 459                 } catch ( CDNNotEnabledException $e ) {
 460                         // CDN not enabled; nothing to see here
 461                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 462                         if ( empty( $params['ignoreMissingSource'] ) ) {
 463                                 $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 464                         }
 465                 } catch ( CloudFilesException $e ) { // some other exception?
 466                         $this->handleException( $e, $status, __METHOD__, $params );
 467                 }
 468
 469                 return $status;
 470         }
 471
 472         /**
 473          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 474          */
 475         protected function getResponseCopy( CF_Async_Op $cfOp, Status $status, array $params ) {
 476                 try {
 477                         $cfOp->getLastResponse();
 478                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 479                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 480                 }
 481         }
 482
 483         protected function doMoveInternal( array $params ) {
 484                 $status = Status::newGood();
 485
 486                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 487                 if ( $srcRel === null ) {
 488                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 489
 490                         return $status;
 491                 }
 492
 493                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 494                 if ( $dstRel === null ) {
 495                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 496
 497                         return $status;
 498                 }
 499
 500                 // (a) Check the source/destination containers and destination object
 501                 try {
 502                         $sContObj = $this->getContainer( $srcCont );
 503                         $dContObj = $this->getContainer( $dstCont );
 504                 } catch ( NoSuchContainerException $e ) {
 505                         if ( empty( $params['ignoreMissingSource'] ) || isset( $sContObj ) ) {
 506                                 $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 507                         }
 508
 509                         return $status;
 510                 } catch ( CloudFilesException $e ) { // some other exception?
 511                         $this->handleException( $e, $status, __METHOD__, $params );
 512
 513                         return $status;
 514                 }
 515
 516                 // (b) Actually move the file to the destination
 517                 try {
 518                         $srcObj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 519                         $dstObj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 520                         $hdrs = array(); // source file headers to override with new values
 521                         // Set any other custom headers if requested
 522                         if ( isset( $params['headers'] ) ) {
 523                                 $hdrs += $this->sanitizeHdrs( $params['headers'] );
 524                         }
 525                         if ( !empty( $params['async'] ) ) { // deferred
 526                                 $op = $sContObj->move_object_to_async( $srcRel, $dContObj, $dstRel, null, $hdrs );
 527                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Move', $op );
 528                                 $status->value->affectedObjects[] = $srcObj;
 529                                 $status->value->affectedObjects[] = $dstObj;
 530                         } else { // actually write the object in Swift
 531                                 $sContObj->move_object_to( $srcRel, $dContObj, $dstRel, null, $hdrs );
 532                                 $this->purgeCDNCache( array( $srcObj ) );
 533                                 $this->purgeCDNCache( array( $dstObj ) );
 534                         }
 535                 } catch ( CDNNotEnabledException $e ) {
 536                         // CDN not enabled; nothing to see here
 537                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 538                         if ( empty( $params['ignoreMissingSource'] ) ) {
 539                                 $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 540                         }
 541                 } catch ( CloudFilesException $e ) { // some other exception?
 542                         $this->handleException( $e, $status, __METHOD__, $params );
 543                 }
 544
 545                 return $status;
 546         }
 547
 548         /**
 549          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 550          */
 551         protected function getResponseMove( CF_Async_Op $cfOp, Status $status, array $params ) {
 552                 try {
 553                         $cfOp->getLastResponse();
 554                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 555                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 556                 }
 557         }
 558
 559         protected function doDeleteInternal( array $params ) {
 560                 $status = Status::newGood();
 561
 562                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 563                 if ( $srcRel === null ) {
 564                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 565
 566                         return $status;
 567                 }
 568
 569                 try {
 570                         $sContObj = $this->getContainer( $srcCont );
 571                         $srcObj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 572                         if ( !empty( $params['async'] ) ) { // deferred
 573                                 $op = $sContObj->delete_object_async( $srcRel );
 574                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Delete', $op );
 575                                 $status->value->affectedObjects[] = $srcObj;
 576                         } else { // actually write the object in Swift
 577                                 $sContObj->delete_object( $srcRel );
 578                                 $this->purgeCDNCache( array( $srcObj ) );
 579                         }
 580                 } catch ( CDNNotEnabledException $e ) {
 581                         // CDN not enabled; nothing to see here
 582                 } catch ( NoSuchContainerException $e ) {
 583                         if ( empty( $params['ignoreMissingSource'] ) ) {
 584                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 585                         }
 586                 } catch ( NoSuchObjectException $e ) {
 587                         if ( empty( $params['ignoreMissingSource'] ) ) {
 588                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 589                         }
 590                 } catch ( CloudFilesException $e ) { // some other exception?
 591                         $this->handleException( $e, $status, __METHOD__, $params );
 592                 }
 593
 594                 return $status;
 595         }
 596
 597         /**
 598          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 599          */
 600         protected function getResponseDelete( CF_Async_Op $cfOp, Status $status, array $params ) {
 601                 try {
 602                         $cfOp->getLastResponse();
 603                 } catch ( NoSuchContainerException $e ) {
 604                         $status->fatal( 'backend-fail-delete', $params['src'] );
 605                 } catch ( NoSuchObjectException $e ) {
 606                         if ( empty( $params['ignoreMissingSource'] ) ) {
 607                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 608                         }
 609                 }
 610         }
 611
 612         protected function doDescribeInternal( array $params ) {
 613                 $status = Status::newGood();
 614
 615                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 616                 if ( $srcRel === null ) {
 617                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 618
 619                         return $status;
 620                 }
 621
 622                 try {
 623                         $sContObj = $this->getContainer( $srcCont );
 624                         // Get the latest version of the current metadata
 625                         $srcObj = $sContObj->get_object( $srcRel,
 626                                 $this->headersFromParams( array( 'latest' => true ) ) );
 627                         // Merge in the metadata updates...
 628                         if ( isset( $params['headers'] ) ) {
 629                                 $srcObj->headers = $this->sanitizeHdrs( $params['headers'] ) + $srcObj->headers;
 630                         }
 631                         $srcObj->sync_metadata(); // save to Swift
 632                         $this->purgeCDNCache( array( $srcObj ) );
 633                 } catch ( CDNNotEnabledException $e ) {
 634                         // CDN not enabled; nothing to see here
 635                 } catch ( NoSuchContainerException $e ) {
 636                         $status->fatal( 'backend-fail-describe', $params['src'] );
 637                 } catch ( NoSuchObjectException $e ) {
 638                         $status->fatal( 'backend-fail-describe', $params['src'] );
 639                 } catch ( CloudFilesException $e ) { // some other exception?
 640                         $this->handleException( $e, $status, __METHOD__, $params );
 641                 }
 642
 643                 return $status;
 644         }
 645
 646         protected function doPrepareInternal( $fullCont, $dir, array $params ) {
 647                 $status = Status::newGood();
 648
 649                 // (a) Check if container already exists
 650                 try {
 651                         $this->getContainer( $fullCont );
 652
 653                         // NoSuchContainerException not thrown: container must exist
 654                         return $status; // already exists
 655                 } catch ( NoSuchContainerException $e ) {
 656                         // NoSuchContainerException thrown: container does not exist
 657                 } catch ( CloudFilesException $e ) { // some other exception?
 658                         $this->handleException( $e, $status, __METHOD__, $params );
 659
 660                         return $status;
 661                 }
 662
 663                 // (b) Create container as needed
 664                 try {
 665                         $contObj = $this->createContainer( $fullCont );
 666                         if ( !empty( $params['noAccess'] ) ) {
 667                                 // Make container private to end-users...
 668                                 $status->merge( $this->doSecureInternal( $fullCont, $dir, $params ) );
 669                         } else {
 670                                 // Make container public to end-users...
 671                                 $status->merge( $this->doPublishInternal( $fullCont, $dir, $params ) );
 672                         }
 673                         if ( $this->swiftUseCDN ) { // Rackspace style CDN
 674                                 $contObj->make_public( $this->swiftCDNExpiry );
 675                         }
 676                 } catch ( CDNNotEnabledException $e ) {
 677                         // CDN not enabled; nothing to see here
 678                 } catch ( CloudFilesException $e ) { // some other exception?
 679                         $this->handleException( $e, $status, __METHOD__, $params );
 680
 681                         return $status;
 682                 }
 683
 684                 return $status;
 685         }
 686
 687         /**
 688          * @see FileBackendStore::doSecureInternal()
 689          * @param string $fullCont
 690          * @param string $dir
 691          * @param array $params
 692          * @return Status
 693          */
 694         protected function doSecureInternal( $fullCont, $dir, array $params ) {
 695                 $status = Status::newGood();
 696                 if ( empty( $params['noAccess'] ) ) {
 697                         return $status; // nothing to do
 698                 }
 699
 700                 // Restrict container from end-users...
 701                 try {
 702                         // doPrepareInternal() should have been called,
 703                         // so the Swift container should already exist...
 704                         $contObj = $this->getContainer( $fullCont ); // normally a cache hit
 705                         // NoSuchContainerException not thrown: container must exist
 706
 707                         // Make container private to end-users...
 708                         $status->merge( $this->setContainerAccess(
 709                                 $contObj,
 710                                 array( $this->auth->username ), // read
 711                                 array( $this->auth->username ) // write
 712                         ) );
 713                         if ( $this->swiftUseCDN && $contObj->is_public() ) { // Rackspace style CDN
 714                                 $contObj->make_private();
 715                         }
 716                 } catch ( CDNNotEnabledException $e ) {
 717                         // CDN not enabled; nothing to see here
 718                 } catch ( CloudFilesException $e ) { // some other exception?
 719                         $this->handleException( $e, $status, __METHOD__, $params );
 720                 }
 721
 722                 return $status;
 723         }
 724
 725         /**
 726          * @see FileBackendStore::doPublishInternal()
 727          * @param string $fullCont
 728          * @param string $dir
 729          * @param array $params
 730          * @return Status
 731          */
 732         protected function doPublishInternal( $fullCont, $dir, array $params ) {
 733                 $status = Status::newGood();
 734
 735                 // Unrestrict container from end-users...
 736                 try {
 737                         // doPrepareInternal() should have been called,
 738                         // so the Swift container should already exist...
 739                         $contObj = $this->getContainer( $fullCont ); // normally a cache hit
 740                         // NoSuchContainerException not thrown: container must exist
 741
 742                         // Make container public to end-users...
 743                         if ( $this->swiftAnonUser != '' ) {
 744                                 $status->merge( $this->setContainerAccess(
 745                                         $contObj,
 746                                         array( $this->auth->username, $this->swiftAnonUser ), // read
 747                                         array( $this->auth->username, $this->swiftAnonUser ) // write
 748                                 ) );
 749                         } else {
 750                                 $status->merge( $this->setContainerAccess(
 751                                         $contObj,
 752                                         array( $this->auth->username, '.r:*' ), // read
 753                                         array( $this->auth->username ) // write
 754                                 ) );
 755                         }
 756                         if ( $this->swiftUseCDN && !$contObj->is_public() ) { // Rackspace style CDN
 757                                 $contObj->make_public();
 758                         }
 759                 } catch ( CDNNotEnabledException $e ) {
 760                         // CDN not enabled; nothing to see here
 761                 } catch ( CloudFilesException $e ) { // some other exception?
 762                         $this->handleException( $e, $status, __METHOD__, $params );
 763                 }
 764
 765                 return $status;
 766         }
 767
 768         protected function doCleanInternal( $fullCont, $dir, array $params ) {
 769                 $status = Status::newGood();
 770
 771                 // Only containers themselves can be removed, all else is virtual
 772                 if ( $dir != '' ) {
 773                         return $status; // nothing to do
 774                 }
 775
 776                 // (a) Check the container
 777                 try {
 778                         $contObj = $this->getContainer( $fullCont, true );
 779                 } catch ( NoSuchContainerException $e ) {
 780                         return $status; // ok, nothing to do
 781                 } catch ( CloudFilesException $e ) { // some other exception?
 782                         $this->handleException( $e, $status, __METHOD__, $params );
 783
 784                         return $status;
 785                 }
 786
 787                 // (b) Delete the container if empty
 788                 if ( $contObj->object_count == 0 ) {
 789                         try {
 790                                 $this->deleteContainer( $fullCont );
 791                         } catch ( NoSuchContainerException $e ) {
 792                                 return $status; // race?
 793                         } catch ( NonEmptyContainerException $e ) {
 794                                 return $status; // race? consistency delay?
 795                         } catch ( CloudFilesException $e ) { // some other exception?
 796                                 $this->handleException( $e, $status, __METHOD__, $params );
 797
 798                                 return $status;
 799                         }
 800                 }
 801
 802                 return $status;
 803         }
 804
 805         protected function doGetFileStat( array $params ) {
 806                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 807                 if ( $srcRel === null ) {
 808                         return false; // invalid storage path
 809                 }
 810
 811                 $stat = false;
 812                 try {
 813                         $contObj = $this->getContainer( $srcCont );
 814                         $srcObj = $contObj->get_object( $srcRel, $this->headersFromParams( $params ) );
 815                         $this->addMissingMetadata( $srcObj, $params['src'] );
 816                         $stat = array(
 817                                 // Convert various random Swift dates to TS_MW
 818                                 'mtime' => $this->convertSwiftDate( $srcObj->last_modified, TS_MW ),
 819                                 'size' => (int)$srcObj->content_length,
 820                                 'sha1' => $srcObj->getMetadataValue( 'Sha1base36' )
 821                         );
 822                 } catch ( NoSuchContainerException $e ) {
 823                 } catch ( NoSuchObjectException $e ) {
 824                 } catch ( CloudFilesException $e ) { // some other exception?
 825                         $stat = null;
 826                         $this->handleException( $e, null, __METHOD__, $params );
 827                 }
 828
 829                 return $stat;
 830         }
 831
 832         /**
 833          * Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT"/"2013-05-11T07:37:27.678360Z".
 834          * Dates might also come in like "2013-05-11T07:37:27.678360" from Swift listings,
 835          * missing the timezone suffix (though Ceph RGW does not appear to have this bug).
 836          *
 837          * @param string $ts
 838          * @param int $format Output format (TS_* constant)
 839          * @return string
 840          * @throws FileBackendError
 841          */
 842         protected function convertSwiftDate( $ts, $format = TS_MW ) {
 843                 try {
 844                         $timestamp = new MWTimestamp( $ts );
 845                         return $timestamp->getTimestamp( $format );
 846                 } catch ( MWException $e ) {
 847                         throw new FileBackendError( $e->getMessage() );
 848                 }
 849         }
 850
 851         /**
 852          * Fill in any missing object metadata and save it to Swift
 853          *
 854          * @param CF_Object $obj
 855          * @param string $path Storage path to object
 856          * @return bool Success
 857          * @throws Exception cloudfiles exceptions
 858          */
 859         protected function addMissingMetadata( CF_Object $obj, $path ) {
 860                 if ( $obj->getMetadataValue( 'Sha1base36' ) !== null ) {
 861                         return true; // nothing to do
 862                 }
 863                 wfProfileIn( __METHOD__ );
 864                 trigger_error( "$path was not stored with SHA-1 metadata.", E_USER_WARNING );
 865                 $status = Status::newGood();
 866                 $scopeLockS = $this->getScopedFileLocks( array( $path ), LockManager::LOCK_UW, $status );
 867                 if ( $status->isOK() ) {
 868                         $tmpFile = $this->getLocalCopy( array( 'src' => $path, 'latest' => 1 ) );
 869                         if ( $tmpFile ) {
 870                                 $hash = $tmpFile->getSha1Base36();
 871                                 if ( $hash !== false ) {
 872                                         $obj->setMetadataValues( array( 'Sha1base36' => $hash ) );
 873                                         $obj->sync_metadata(); // save to Swift
 874                                         wfProfileOut( __METHOD__ );
 875
 876                                         return true; // success
 877                                 }
 878                         }
 879                 }
 880                 trigger_error( "Unable to set SHA-1 metadata for $path", E_USER_WARNING );
 881                 $obj->setMetadataValues( array( 'Sha1base36' => false ) );
 882                 wfProfileOut( __METHOD__ );
 883
 884                 return false; // failed
 885         }
 886
 887         protected function doGetFileContentsMulti( array $params ) {
 888                 $contents = array();
 889
 890                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
 891                 // Blindly create tmp files and stream to them, catching any exception if the file does
 892                 // not exist. Doing stats here is useless and will loop infinitely in addMissingMetadata().
 893                 foreach ( array_chunk( $params['srcs'], $params['concurrency'] ) as $pathBatch ) {
 894                         $cfOps = array(); // (path => CF_Async_Op)
 895
 896                         foreach ( $pathBatch as $path ) { // each path in this concurrent batch
 897                                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
 898                                 if ( $srcRel === null ) {
 899                                         $contents[$path] = false;
 900                                         continue;
 901                                 }
 902                                 $data = false;
 903                                 try {
 904                                         $sContObj = $this->getContainer( $srcCont );
 905                                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 906                                         // Create a new temporary memory file...
 907                                         $handle = fopen( 'php://temp', 'wb' );
 908                                         if ( $handle ) {
 909                                                 $headers = $this->headersFromParams( $params );
 910                                                 if ( count( $pathBatch ) > 1 ) {
 911                                                         $cfOps[$path] = $obj->stream_async( $handle, $headers );
 912                                                         $cfOps[$path]->_file_handle = $handle; // close this later
 913                                                 } else {
 914                                                         $obj->stream( $handle, $headers );
 915                                                         rewind( $handle ); // start from the beginning
 916                                                         $data = stream_get_contents( $handle );
 917                                                         fclose( $handle );
 918                                                 }
 919                                         } else {
 920                                                 $data = false;
 921                                         }
 922                                 } catch ( NoSuchContainerException $e ) {
 923                                         $data = false;
 924                                 } catch ( NoSuchObjectException $e ) {
 925                                         $data = false;
 926                                 } catch ( CloudFilesException $e ) { // some other exception?
 927                                         $data = false;
 928                                         $this->handleException( $e, null, __METHOD__, array( 'src' => $path ) + $ep );
 929                                 }
 930                                 $contents[$path] = $data;
 931                         }
 932
 933                         $batch = new CF_Async_Op_Batch( $cfOps );
 934                         $cfOps = $batch->execute();
 935                         foreach ( $cfOps as $path => $cfOp ) {
 936                                 try {
 937                                         $cfOp->getLastResponse();
 938                                         rewind( $cfOp->_file_handle ); // start from the beginning
 939                                         $contents[$path] = stream_get_contents( $cfOp->_file_handle );
 940                                 } catch ( NoSuchContainerException $e ) {
 941                                         $contents[$path] = false;
 942                                 } catch ( NoSuchObjectException $e ) {
 943                                         $contents[$path] = false;
 944                                 } catch ( CloudFilesException $e ) { // some other exception?
 945                                         $contents[$path] = false;
 946                                         $this->handleException( $e, null, __METHOD__, array( 'src' => $path ) + $ep );
 947                                 }
 948                                 fclose( $cfOp->_file_handle ); // close open handle
 949                         }
 950                 }
 951
 952                 return $contents;
 953         }
 954
 955         /**
 956          * @see FileBackendStore::doDirectoryExists()
 957          * @param string $fullCont
 958          * @param string $dir
 959          * @param array $params
 960          * @return bool|null
 961          */
 962         protected function doDirectoryExists( $fullCont, $dir, array $params ) {
 963                 try {
 964                         $container = $this->getContainer( $fullCont );
 965                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
 966
 967                         return ( count( $container->list_objects( 1, null, $prefix ) ) > 0 );
 968                 } catch ( NoSuchContainerException $e ) {
 969                         return false;
 970                 } catch ( CloudFilesException $e ) { // some other exception?
 971                         $this->handleException( $e, null, __METHOD__,
 972                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
 973                 }
 974
 975                 return null; // error
 976         }
 977
 978         /**
 979          * @see FileBackendStore::getDirectoryListInternal()
 980          * @param string $fullCont
 981          * @param string $dir
 982          * @param array $params
 983          * @return SwiftFileBackendDirList
 984          */
 985         public function getDirectoryListInternal( $fullCont, $dir, array $params ) {
 986                 return new SwiftFileBackendDirList( $this, $fullCont, $dir, $params );
 987         }
 988
 989         /**
 990          * @see FileBackendStore::getFileListInternal()
 991          * @param string $fullCont
 992          * @param string $dir
 993          * @param array $params
 994          * @return SwiftFileBackendFileList
 995          */
 996         public function getFileListInternal( $fullCont, $dir, array $params ) {
 997                 return new SwiftFileBackendFileList( $this, $fullCont, $dir, $params );
 998         }
 999
1000         /**
1001          * Do not call this function outside of SwiftFileBackendFileList
1002          *
1003          * @param string $fullCont Resolved container name
1004          * @param string $dir Resolved storage directory with no trailing slash
1005          * @param string|null $after Resolved container relative path to list items after
1006          * @param int $limit Max number of items to list
1007          * @param array $params Parameters for getDirectoryList()
1008          * @return array List of container relative resolved paths of directories directly under $dir
1009          * @throws FileBackendError
1010          */
1011         public function getDirListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
1012                 $dirs = array();
1013                 if ( $after === INF ) {
1014                         return $dirs; // nothing more
1015                 }
1016
1017                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
1018                 try {
1019                         $container = $this->getContainer( $fullCont );
1020                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
1021                         // Non-recursive: only list dirs right under $dir
1022                         if ( !empty( $params['topOnly'] ) ) {
1023                                 $objects = $container->list_objects( $limit, $after, $prefix, null, '/' );
1024                                 foreach ( $objects as $object ) { // files and directories
1025                                         if ( substr( $object, -1 ) === '/' ) {
1026                                                 $dirs[] = $object; // directories end in '/'
1027                                         }
1028                                 }
1029                         // Recursive: list all dirs under $dir and its subdirs
1030                         } else {
1031                                 // Get directory from last item of prior page
1032                                 $lastDir = $this->getParentDir( $after ); // must be first page
1033                                 $objects = $container->list_objects( $limit, $after, $prefix );
1034                                 foreach ( $objects as $object ) { // files
1035                                         $objectDir = $this->getParentDir( $object ); // directory of object
1036                                         if ( $objectDir !== false && $objectDir !== $dir ) {
1037                                                 // Swift stores paths in UTF-8, using binary sorting.
1038                                                 // See function "create_container_table" in common/db.py.
1039                                                 // If a directory is not "greater" than the last one,
1040                                                 // then it was already listed by the calling iterator.
1041                                                 if ( strcmp( $objectDir, $lastDir ) > 0 ) {
1042                                                         $pDir = $objectDir;
1043                                                         do { // add dir and all its parent dirs
1044                                                                 $dirs[] = "{$pDir}/";
1045                                                                 $pDir = $this->getParentDir( $pDir );
1046                                                         } while ( $pDir !== false // sanity
1047                                                                 && strcmp( $pDir, $lastDir ) > 0 // not done already
1048                                                                 && strlen( $pDir ) > strlen( $dir ) // within $dir
1049                                                         );
1050                                                 }
1051                                                 $lastDir = $objectDir;
1052                                         }
1053                                 }
1054                         }
1055                         // Page on the unfiltered directory listing (what is returned may be filtered)
1056                         if ( count( $objects ) < $limit ) {
1057                                 $after = INF; // avoid a second RTT
1058                         } else {
1059                                 $after = end( $objects ); // update last item
1060                         }
1061                 } catch ( NoSuchContainerException $e ) {
1062                 } catch ( CloudFilesException $e ) { // some other exception?
1063                         $this->handleException( $e, null, __METHOD__,
1064                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
1065                         throw new FileBackendError( "Got " . get_class( $e ) . " exception." );
1066                 }
1067
1068                 return $dirs;
1069         }
1070
1071         protected function getParentDir( $path ) {
1072                 return ( strpos( $path, '/' ) !== false ) ? dirname( $path ) : false;
1073         }
1074
1075         /**
1076          * Do not call this function outside of SwiftFileBackendFileList
1077          *
1078          * @param string $fullCont Resolved container name
1079          * @param string $dir Resolved storage directory with no trailing slash
1080          * @param string|null $after Resolved container relative path of file to list items after
1081          * @param int $limit Max number of items to list
1082          * @param array $params Parameters for getDirectoryList()
1083          * @return array List of resolved container relative paths of files under $dir
1084          * @throws FileBackendError
1085          */
1086         public function getFileListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
1087                 $files = array(); // list of (path, stat array or null) entries
1088                 if ( $after === INF ) {
1089                         return $files; // nothing more
1090                 }
1091
1092                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
1093                 try {
1094                         $container = $this->getContainer( $fullCont );
1095                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
1096
1097                         // $objects will contain a list of unfiltered names or CF_Object items
1098                         // Non-recursive: only list files right under $dir
1099                         if ( !empty( $params['topOnly'] ) ) {
1100                                 if ( !empty( $params['adviseStat'] ) ) {
1101                                         // Note: get_objects() does not include directories
1102                                         $objects = $container->get_objects( $limit, $after, $prefix, null, '/' );
1103                                 } else {
1104                                         // Note: list_objects() includes directories here
1105                                         $objects = $container->list_objects( $limit, $after, $prefix, null, '/' );
1106                                 }
1107                                 $files = $this->buildFileObjectListing( $params, $dir, $objects );
1108                         // Recursive: list all files under $dir and its subdirs
1109                         } else {
1110                                 // Note: get_objects()/list_objects() here only return file objects
1111                                 if ( !empty( $params['adviseStat'] ) ) {
1112                                         $objects = $container->get_objects( $limit, $after, $prefix );
1113                                 } else {
1114                                         $objects = $container->list_objects( $limit, $after, $prefix );
1115                                 }
1116                                 $files = $this->buildFileObjectListing( $params, $dir, $objects );
1117                         }
1118                         // Page on the unfiltered object listing (what is returned may be filtered)
1119                         if ( count( $objects ) < $limit ) {
1120                                 $after = INF; // avoid a second RTT
1121                         } else {
1122                                 $after = end( $objects ); // update last item
1123                                 $after = is_object( $after ) ? $after->name : $after;
1124                         }
1125                 } catch ( NoSuchContainerException $e ) {
1126                 } catch ( CloudFilesException $e ) { // some other exception?
1127                         $this->handleException( $e, null, __METHOD__,
1128                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
1129                         throw new FileBackendError( "Got " . get_class( $e ) . " exception." );
1130                 }
1131
1132                 return $files;
1133         }
1134
1135         /**
1136          * Build a list of file objects, filtering out any directories
1137          * and extracting any stat info if provided in $objects (for CF_Objects)
1138          *
1139          * @param array $params Parameters for getDirectoryList()
1140          * @param string $dir Resolved container directory path
1141          * @param array $objects List of CF_Object items or object names
1142          * @return array List of (names,stat array or null) entries
1143          */
1144         private function buildFileObjectListing( array $params, $dir, array $objects ) {
1145                 $names = array();
1146                 foreach ( $objects as $object ) {
1147                         if ( is_object( $object ) ) {
1148                                 $stat = array(
1149                                         // Convert various random Swift dates to TS_MW
1150                                         'mtime' => $this->convertSwiftDate( $object->last_modified, TS_MW ),
1151                                         'size' => (int)$object->content_length,
1152                                         'latest' => false // eventually consistent
1153                                 );
1154                                 $names[] = array( $object->name, $stat );
1155                         } elseif ( substr( $object, -1 ) !== '/' ) {
1156                                 // Omit directories, which end in '/' in listings
1157                                 $names[] = array( $object, null );
1158                         }
1159                 }
1160
1161                 return $names;
1162         }
1163
1164         /**
1165          * Do not call this function outside of SwiftFileBackendFileList
1166          *
1167          * @param string $path Storage path
1168          * @param array $val Stat value
1169          */
1170         public function loadListingStatInternal( $path, array $val ) {
1171                 $this->cheapCache->set( $path, 'stat', $val );
1172         }
1173
1174         protected function doGetFileSha1base36( array $params ) {
1175                 $stat = $this->getFileStat( $params );
1176                 if ( $stat ) {
1177                         if ( !isset( $stat['sha1'] ) ) {
1178                                 // Stat entries filled by file listings don't include SHA1
1179                                 $this->clearCache( array( $params['src'] ) );
1180                                 $stat = $this->getFileStat( $params );
1181                         }
1182
1183                         return $stat['sha1'];
1184                 } else {
1185                         return false;
1186                 }
1187         }
1188
1189         protected function doStreamFile( array $params ) {
1190                 $status = Status::newGood();
1191
1192                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
1193                 if ( $srcRel === null ) {
1194                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
1195                 }
1196
1197                 try {
1198                         $cont = $this->getContainer( $srcCont );
1199                 } catch ( NoSuchContainerException $e ) {
1200                         $status->fatal( 'backend-fail-stream', $params['src'] );
1201
1202                         return $status;
1203                 } catch ( CloudFilesException $e ) { // some other exception?
1204                         $this->handleException( $e, $status, __METHOD__, $params );
1205
1206                         return $status;
1207                 }
1208
1209                 try {
1210                         $output = fopen( 'php://output', 'wb' );
1211                         $obj = new CF_Object( $cont, $srcRel, false, false ); // skip HEAD
1212                         $obj->stream( $output, $this->headersFromParams( $params ) );
1213                 } catch ( NoSuchObjectException $e ) {
1214                         $status->fatal( 'backend-fail-stream', $params['src'] );
1215                 } catch ( CloudFilesException $e ) { // some other exception?
1216                         $this->handleException( $e, $status, __METHOD__, $params );
1217                 }
1218
1219                 return $status;
1220         }
1221
1222         protected function doGetLocalCopyMulti( array $params ) {
1223                 $tmpFiles = array();
1224
1225                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
1226                 // Blindly create tmp files and stream to them, catching any exception if the file does
1227                 // not exist. Doing a stat here is useless causes infinite loops in addMissingMetadata().
1228                 foreach ( array_chunk( $params['srcs'], $params['concurrency'] ) as $pathBatch ) {
1229                         $cfOps = array(); // (path => CF_Async_Op)
1230
1231                         foreach ( $pathBatch as $path ) { // each path in this concurrent batch
1232                                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
1233                                 if ( $srcRel === null ) {
1234                                         $tmpFiles[$path] = null;
1235                                         continue;
1236                                 }
1237                                 $tmpFile = null;
1238                                 try {
1239                                         $sContObj = $this->getContainer( $srcCont );
1240                                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
1241                                         // Get source file extension
1242                                         $ext = FileBackend::extensionFromPath( $path );
1243                                         // Create a new temporary file...
1244                                         $tmpFile = TempFSFile::factory( 'localcopy_', $ext );
1245                                         if ( $tmpFile ) {
1246                                                 $handle = fopen( $tmpFile->getPath(), 'wb' );
1247                                                 if ( $handle ) {
1248                                                         $headers = $this->headersFromParams( $params );
1249                                                         if ( count( $pathBatch ) > 1 ) {
1250                                                                 $cfOps[$path] = $obj->stream_async( $handle, $headers );
1251                                                                 $cfOps[$path]->_file_handle = $handle; // close this later
1252                                                         } else {
1253                                                                 $obj->stream( $handle, $headers );
1254                                                                 fclose( $handle );
1255                                                         }
1256                                                 } else {
1257                                                         $tmpFile = null;
1258                                                 }
1259                                         }
1260                                 } catch ( NoSuchContainerException $e ) {
1261                                         $tmpFile = null;
1262                                 } catch ( NoSuchObjectException $e ) {
1263                                         $tmpFile = null;
1264                                 } catch ( CloudFilesException $e ) { // some other exception?
1265                                         $tmpFile = null;
1266                                         $this->handleException( $e, null, __METHOD__, array( 'src' => $path ) + $ep );
1267                                 }
1268                                 $tmpFiles[$path] = $tmpFile;
1269                         }
1270
1271                         $batch = new CF_Async_Op_Batch( $cfOps );
1272                         $cfOps = $batch->execute();
1273                         foreach ( $cfOps as $path => $cfOp ) {
1274                                 try {
1275                                         $cfOp->getLastResponse();
1276                                 } catch ( NoSuchContainerException $e ) {
1277                                         $tmpFiles[$path] = null;
1278                                 } catch ( NoSuchObjectException $e ) {
1279                                         $tmpFiles[$path] = null;
1280                                 } catch ( CloudFilesException $e ) { // some other exception?
1281                                         $tmpFiles[$path] = null;
1282                                         $this->handleException( $e, null, __METHOD__, array( 'src' => $path ) + $ep );
1283                                 }
1284                                 fclose( $cfOp->_file_handle ); // close open handle
1285                         }
1286                 }
1287
1288                 return $tmpFiles;
1289         }
1290
1291         public function getFileHttpUrl( array $params ) {
1292                 if ( $this->swiftTempUrlKey != '' ||
1293                         ( $this->rgwS3AccessKey != '' && $this->rgwS3SecretKey != '' )
1294                 ) {
1295                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
1296                         if ( $srcRel === null ) {
1297                                 return null; // invalid path
1298                         }
1299                         try {
1300                                 $ttl = isset( $params['ttl'] ) ? $params['ttl'] : 86400;
1301                                 $sContObj = $this->getContainer( $srcCont );
1302                                 $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
1303                                 if ( $this->swiftTempUrlKey != '' ) {
1304                                         return $obj->get_temp_url( $this->swiftTempUrlKey, $ttl, "GET" );
1305                                 } else { // give S3 API URL for rgw
1306                                         $expires = time() + $ttl;
1307                                         // Path for signature starts with the bucket
1308                                         $spath = '/' . rawurlencode( $srcCont ) . '/' .
1309                                                 str_replace( '%2F', '/', rawurlencode( $srcRel ) );
1310                                         // Calculate the hash
1311                                         $signature = base64_encode( hash_hmac(
1312                                                 'sha1',
1313                                                 "GET\n\n\n{$expires}\n{$spath}",
1314                                                 $this->rgwS3SecretKey,
1315                                                 true // raw
1316                                         ) );
1317
1318                                         // See http://s3.amazonaws.com/doc/s3-developer-guide/RESTAuthentication.html.
1319                                         // Note: adding a newline for empty CanonicalizedAmzHeaders does not work.
1320                                         return wfAppendQuery(
1321                                                 str_replace( '/swift/v1', '', // S3 API is the rgw default
1322                                                         $sContObj->cfs_http->getStorageUrl() . $spath ),
1323                                                 array(
1324                                                         'Signature' => $signature,
1325                                                         'Expires' => $expires,
1326                                                         'AWSAccessKeyId' => $this->rgwS3AccessKey )
1327                                         );
1328                                 }
1329                         } catch ( NoSuchContainerException $e ) {
1330                         } catch ( CloudFilesException $e ) { // some other exception?
1331                                 $this->handleException( $e, null, __METHOD__, $params );
1332                         }
1333                 }
1334
1335                 return null;
1336         }
1337
1338         protected function directoriesAreVirtual() {
1339                 return true;
1340         }
1341
1342         /**
1343          * Get headers to send to Swift when reading a file based
1344          * on a FileBackend params array, e.g. that of getLocalCopy().
1345          * $params is currently only checked for a 'latest' flag.
1346          *
1347          * @param array $params
1348          * @return array
1349          */
1350         protected function headersFromParams( array $params ) {
1351                 $hdrs = array();
1352                 if ( !empty( $params['latest'] ) ) {
1353                         $hdrs[] = 'X-Newest: true';
1354                 }
1355
1356                 return $hdrs;
1357         }
1358
1359         protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
1360                 $statuses = array();
1361
1362                 $cfOps = array(); // list of CF_Async_Op objects
1363                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
1364                         $cfOps[$index] = $fileOpHandle->cfOp;
1365                 }
1366                 $batch = new CF_Async_Op_Batch( $cfOps );
1367
1368                 $cfOps = $batch->execute();
1369                 foreach ( $cfOps as $index => $cfOp ) {
1370                         $status = Status::newGood();
1371                         $function = 'getResponse' . $fileOpHandles[$index]->call;
1372                         try { // catch exceptions; update status
1373                                 $this->$function( $cfOp, $status, $fileOpHandles[$index]->params );
1374                                 $this->purgeCDNCache( $fileOpHandles[$index]->affectedObjects );
1375                         } catch ( CloudFilesException $e ) { // some other exception?
1376                                 $this->handleException( $e, $status,
1377                                         __CLASS__ . ":$function", $fileOpHandles[$index]->params );
1378                         }
1379                         $statuses[$index] = $status;
1380                 }
1381
1382                 return $statuses;
1383         }
1384
1385         /**
1386          * Set read/write permissions for a Swift container.
1387          *
1388          * @see http://swift.openstack.org/misc.html#acls
1389          *
1390          * In general, we don't allow listings to end-users. It's not useful, isn't well-defined
1391          * (lists are truncated to 10000 item with no way to page), and is just a performance risk.
1392          *
1393          * @param CF_Container $contObj Swift container
1394          * @param array $readGrps List of the possible criteria for a request to have
1395          * access to read a container. Each item is one of the following formats:
1396          *   - account:user        : Grants access if the request is by the given user
1397          *   - ".r:<regex>"        : Grants access if the request is from a referrer host that
1398          *                           matches the expression and the request is not for a listing.
1399          *                           Setting this to '*' effectively makes a container public.
1400          *   -".rlistings:<regex>" : Grants access if the request is from a referrer host that
1401          *                           matches the expression and the request is for a listing.
1402          * @param array $writeGrps A list of the possible criteria for a request to have
1403          * access to write to a container. Each item is of the following format:
1404          *   - account:user       : Grants access if the request is by the given user
1405          * @return Status
1406          */
1407         protected function setContainerAccess(
1408                 CF_Container $contObj, array $readGrps, array $writeGrps
1409         ) {
1410                 $creds = $contObj->cfs_auth->export_credentials();
1411
1412                 $url = $creds['storage_url'] . '/' . rawurlencode( $contObj->name );
1413
1414                 // Note: 10 second timeout consistent with php-cloudfiles
1415                 $req = MWHttpRequest::factory( $url, array( 'method' => 'POST', 'timeout' => 10 ) );
1416                 $req->setHeader( 'X-Auth-Token', $creds['auth_token'] );
1417                 $req->setHeader( 'X-Container-Read', implode( ',', $readGrps ) );
1418                 $req->setHeader( 'X-Container-Write', implode( ',', $writeGrps ) );
1419
1420                 return $req->execute(); // should return 204
1421         }
1422
1423         /**
1424          * Purge the CDN cache of affected objects if CDN caching is enabled.
1425          * This is for Rackspace/Akamai CDNs.
1426          *
1427          * @param array $objects List of CF_Object items
1428          */
1429         public function purgeCDNCache( array $objects ) {
1430                 if ( $this->swiftUseCDN && $this->swiftCDNPurgable ) {
1431                         foreach ( $objects as $object ) {
1432                                 try {
1433                                         $object->purge_from_cdn();
1434                                 } catch ( CDNNotEnabledException $e ) {
1435                                         // CDN not enabled; nothing to see here
1436                                 } catch ( CloudFilesException $e ) {
1437                                         $this->handleException( $e, null, __METHOD__,
1438                                                 array( 'cont' => $object->container->name, 'obj' => $object->name ) );
1439                                 }
1440                         }
1441                 }
1442         }
1443
1444         /**
1445          * Get an authenticated connection handle to the Swift proxy
1446          *
1447          * @throws CloudFilesException
1448          * @throws CloudFilesException|Exception
1449          * @return CF_Connection|bool False on failure
1450          */
1451         protected function getConnection() {
1452                 if ( $this->connException instanceof CloudFilesException ) {
1453                         if ( ( time() - $this->connErrorTime ) < 60 ) {
1454                                 throw $this->connException; // failed last attempt; don't bother
1455                         } else { // actually retry this time
1456                                 $this->connException = null;
1457                                 $this->connErrorTime = 0;
1458                         }
1459                 }
1460                 // Session keys expire after a while, so we renew them periodically
1461                 $reAuth = ( ( time() - $this->sessionStarted ) > $this->authTTL );
1462                 // Authenticate with proxy and get a session key...
1463                 if ( !$this->conn || $reAuth ) {
1464                         $this->sessionStarted = 0;
1465                         $this->connContainerCache->clear();
1466                         $cacheKey = $this->getCredsCacheKey( $this->auth->username );
1467                         $creds = $this->srvCache->get( $cacheKey ); // credentials
1468                         if ( is_array( $creds ) ) { // cache hit
1469                                 $this->auth->load_cached_credentials(
1470                                         $creds['auth_token'], $creds['storage_url'], $creds['cdnm_url'] );
1471                                 $this->sessionStarted = time() - ceil( $this->authTTL / 2 ); // skew for worst case
1472                         } else { // cache miss
1473                                 try {
1474                                         $this->auth->authenticate();
1475                                         $creds = $this->auth->export_credentials();
1476                                         $this->srvCache->add( $cacheKey, $creds, ceil( $this->authTTL / 2 ) ); // cache
1477                                         $this->sessionStarted = time();
1478                                 } catch ( CloudFilesException $e ) {
1479                                         $this->connException = $e; // don't keep re-trying
1480                                         $this->connErrorTime = time();
1481                                         throw $e; // throw it back
1482                                 }
1483                         }
1484                         if ( $this->conn ) { // re-authorizing?
1485                                 $this->conn->close(); // close active cURL handles in CF_Http object
1486                         }
1487                         $this->conn = new CF_Connection( $this->auth );
1488                 }
1489
1490                 return $this->conn;
1491         }
1492
1493         /**
1494          * Close the connection to the Swift proxy
1495          */
1496         protected function closeConnection() {
1497                 if ( $this->conn ) {
1498                         $this->conn->close(); // close active cURL handles in CF_Http object
1499                         $this->conn = null;
1500                         $this->sessionStarted = 0;
1501                         $this->connContainerCache->clear();
1502                 }
1503         }
1504
1505         /**
1506          * Get the cache key for a container
1507          *
1508          * @param string $username
1509          * @return string
1510          */
1511         private function getCredsCacheKey( $username ) {
1512                 return wfMemcKey( 'backend', $this->getName(), 'usercreds', $username );
1513         }
1514
1515         /**
1516          * Get a Swift container object, possibly from process cache.
1517          * Use $reCache if the file count or byte count is needed.
1518          *
1519          * @param string $container Container name
1520          * @param bool $bypassCache Bypass all caches and load from Swift
1521          * @return CF_Container
1522          * @throws CloudFilesException
1523          */
1524         protected function getContainer( $container, $bypassCache = false ) {
1525                 $conn = $this->getConnection(); // Swift proxy connection
1526                 if ( $bypassCache ) { // purge cache
1527                         $this->connContainerCache->clear( $container );
1528                 } elseif ( !$this->connContainerCache->has( $container, 'obj' ) ) {
1529                         $this->primeContainerCache( array( $container ) ); // check persistent cache
1530                 }
1531                 if ( !$this->connContainerCache->has( $container, 'obj' ) ) {
1532                         $contObj = $conn->get_container( $container );
1533                         // NoSuchContainerException not thrown: container must exist
1534                         $this->connContainerCache->set( $container, 'obj', $contObj ); // cache it
1535                         if ( !$bypassCache ) {
1536                                 $this->setContainerCache( $container, // update persistent cache
1537                                         array( 'bytes' => $contObj->bytes_used, 'count' => $contObj->object_count )
1538                                 );
1539                         }
1540                 }
1541
1542                 return $this->connContainerCache->get( $container, 'obj' );
1543         }
1544
1545         /**
1546          * Create a Swift container
1547          *
1548          * @param string $container Container name
1549          * @return CF_Container
1550          * @throws CloudFilesException
1551          */
1552         protected function createContainer( $container ) {
1553                 $conn = $this->getConnection(); // Swift proxy connection
1554                 $contObj = $conn->create_container( $container );
1555                 $this->connContainerCache->set( $container, 'obj', $contObj ); // cache
1556                 return $contObj;
1557         }
1558
1559         /**
1560          * Delete a Swift container
1561          *
1562          * @param string $container Container name
1563          * @throws CloudFilesException
1564          */
1565         protected function deleteContainer( $container ) {
1566                 $conn = $this->getConnection(); // Swift proxy connection
1567                 $this->connContainerCache->clear( $container ); // purge
1568                 $conn->delete_container( $container );
1569         }
1570
1571         protected function doPrimeContainerCache( array $containerInfo ) {
1572                 try {
1573                         $conn = $this->getConnection(); // Swift proxy connection
1574                         foreach ( $containerInfo as $container => $info ) {
1575                                 $contObj = new CF_Container( $conn->cfs_auth, $conn->cfs_http,
1576                                         $container, $info['count'], $info['bytes'] );
1577                                 $this->connContainerCache->set( $container, 'obj', $contObj );
1578                         }
1579                 } catch ( CloudFilesException $e ) { // some other exception?
1580                         $this->handleException( $e, null, __METHOD__, array() );
1581                 }
1582         }
1583
1584         /**
1585          * Log an unexpected exception for this backend.
1586          * This also sets the Status object to have a fatal error.
1587          *
1588          * @param Exception $e
1589          * @param Status $status null
1590          * @param string $func
1591          * @param array $params
1592          */
1593         protected function handleException( Exception $e, $status, $func, array $params ) {
1594                 if ( $status instanceof Status ) {
1595                         if ( $e instanceof AuthenticationException ) {
1596                                 $status->fatal( 'backend-fail-connect', $this->name );
1597                         } else {
1598                                 $status->fatal( 'backend-fail-internal', $this->name );
1599                         }
1600                 }
1601                 if ( $e->getMessage() ) {
1602                         trigger_error( "$func: " . $e->getMessage(), E_USER_WARNING );
1603                 }
1604                 if ( $e instanceof InvalidResponseException ) { // possibly a stale token
1605                         $this->srvCache->delete( $this->getCredsCacheKey( $this->auth->username ) );
1606                         $this->closeConnection(); // force a re-connect and re-auth next time
1607                 }
1608                 wfDebugLog( 'SwiftBackend',
1609                         get_class( $e ) . " in '{$func}' (given '" . FormatJson::encode( $params ) . "')" .
1610                         ( $e->getMessage() ? ": {$e->getMessage()}" : "" )
1611                 );
1612         }
1613 }
1614
1615 /**
1616  * @see FileBackendStoreOpHandle
1617  */
1618 class SwiftFileOpHandle extends FileBackendStoreOpHandle {
1619         /** @var CF_Async_Op */
1620         public $cfOp;
1621
1622         /** @var array */
1623         public $affectedObjects = array();
1624
1625         /**
1626          * @param SwiftFileBackend $backend
1627          * @param array $params
1628          * @param string $call
1629          * @param CF_Async_Op $cfOp
1630          */
1631         public function __construct(
1632                 SwiftFileBackend $backend, array $params, $call, CF_Async_Op $cfOp
1633         ) {
1634                 $this->backend = $backend;
1635                 $this->params = $params;
1636                 $this->call = $call;
1637                 $this->cfOp = $cfOp;
1638         }
1639 }
1640
1641 /**
1642  * SwiftFileBackend helper class to page through listings.
1643  * Swift also has a listing limit of 10,000 objects for sanity.
1644  * Do not use this class from places outside SwiftFileBackend.
1645  *
1646  * @ingroup FileBackend
1647  */
1648 abstract class SwiftFileBackendList implements Iterator {
1649         /** @var array List of path or (path,stat array) entries */
1650         protected $bufferIter = array();
1651
1652         /** @var string List items *after* this path */
1653         protected $bufferAfter = null;
1654
1655         /** @var int */
1656         protected $pos = 0;
1657
1658         /** @var array */
1659         protected $params = array();
1660
1661         /** @var SwiftFileBackend */
1662         protected $backend;
1663
1664         /** @var string Container name */
1665         protected $container;
1666
1667         /** @var string Storage directory */
1668         protected $dir;
1669
1670         /** @var int */
1671         protected $suffixStart;
1672
1673         const PAGE_SIZE = 9000; // file listing buffer size
1674
1675         /**
1676          * @param SwiftFileBackend $backend
1677          * @param string $fullCont Resolved container name
1678          * @param string $dir Resolved directory relative to container
1679          * @param array $params
1680          */
1681         public function __construct( SwiftFileBackend $backend, $fullCont, $dir, array $params ) {
1682                 $this->backend = $backend;
1683                 $this->container = $fullCont;
1684                 $this->dir = $dir;
1685                 if ( substr( $this->dir, -1 ) === '/' ) {
1686                         $this->dir = substr( $this->dir, 0, -1 ); // remove trailing slash
1687                 }
1688                 if ( $this->dir == '' ) { // whole container
1689                         $this->suffixStart = 0;
1690                 } else { // dir within container
1691                         $this->suffixStart = strlen( $this->dir ) + 1; // size of "path/to/dir/"
1692                 }
1693                 $this->params = $params;
1694         }
1695
1696         /**
1697          * @see Iterator::key()
1698          * @return int
1699          */
1700         public function key() {
1701                 return $this->pos;
1702         }
1703
1704         /**
1705          * @see Iterator::next()
1706          */
1707         public function next() {
1708                 // Advance to the next file in the page
1709                 next( $this->bufferIter );
1710                 ++$this->pos;
1711                 // Check if there are no files left in this page and
1712                 // advance to the next page if this page was not empty.
1713                 if ( !$this->valid() && count( $this->bufferIter ) ) {
1714                         $this->bufferIter = $this->pageFromList(
1715                                 $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1716                         ); // updates $this->bufferAfter
1717                 }
1718         }
1719
1720         /**
1721          * @see Iterator::rewind()
1722          */
1723         public function rewind() {
1724                 $this->pos = 0;
1725                 $this->bufferAfter = null;
1726                 $this->bufferIter = $this->pageFromList(
1727                         $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1728                 ); // updates $this->bufferAfter
1729         }
1730
1731         /**
1732          * @see Iterator::valid()
1733          * @return bool
1734          */
1735         public function valid() {
1736                 if ( $this->bufferIter === null ) {
1737                         return false; // some failure?
1738                 } else {
1739                         return ( current( $this->bufferIter ) !== false ); // no paths can have this value
1740                 }
1741         }
1742
1743         /**
1744          * Get the given list portion (page)
1745          *
1746          * @param string $container Resolved container name
1747          * @param string $dir Resolved path relative to container
1748          * @param string $after null
1749          * @param int $limit
1750          * @param array $params
1751          * @return Traversable|array
1752          */
1753         abstract protected function pageFromList( $container, $dir, &$after, $limit, array $params );
1754 }
1755
1756 /**
1757  * Iterator for listing directories
1758  */
1759 class SwiftFileBackendDirList extends SwiftFileBackendList {
1760         /**
1761          * @see Iterator::current()
1762          * @return string|bool String (relative path) or false
1763          */
1764         public function current() {
1765                 return substr( current( $this->bufferIter ), $this->suffixStart, -1 );
1766         }
1767
1768         /**
1769          * @see SwiftFileBackendList::pageFromList()
1770          * @param string $container
1771          * @param string $dir
1772          * @param string $after
1773          * @param int $limit
1774          * @param array $params
1775          * @return array
1776          */
1777         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1778                 return $this->backend->getDirListPageInternal( $container, $dir, $after, $limit, $params );
1779         }
1780 }
1781
1782 /**
1783  * Iterator for listing regular files
1784  */
1785 class SwiftFileBackendFileList extends SwiftFileBackendList {
1786         /**
1787          * @see Iterator::current()
1788          * @return string|bool String (relative path) or false
1789          */
1790         public function current() {
1791                 list( $path, $stat ) = current( $this->bufferIter );
1792                 $relPath = substr( $path, $this->suffixStart );
1793                 if ( is_array( $stat ) ) {
1794                         $storageDir = rtrim( $this->params['dir'], '/' );
1795                         $this->backend->loadListingStatInternal( "$storageDir/$relPath", $stat );
1796                 }
1797
1798                 return $relPath;
1799         }
1800
1801         /**
1802          * @see SwiftFileBackendList::pageFromList()
1803          * @param string $container
1804          * @param string $dir
1805          * @param string $after
1806          * @param int $limit
1807          * @param array $params
1808          * @return array
1809          */
1810         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1811                 return $this->backend->getFileListPageInternal( $container, $dir, $after, $limit, $params );
1812         }
1813 }