includes/filerepo/backend/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 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 */
  41         protected $auth; // Swift authentication handler
  42         protected $authTTL; // integer seconds
  43         protected $swiftAnonUser; // string; username to handle unauthenticated requests
  44         protected $swiftUseCDN; // boolean; whether CloudFiles CDN is enabled
  45         protected $maxContCacheSize = 300; // integer; max containers with entries
  46
  47         /** @var CF_Connection */
  48         protected $conn; // Swift connection handle
  49         protected $connStarted = 0; // integer UNIX timestamp
  50         protected $connContainers = array(); // container object cache
  51
  52         /**
  53          * @see FileBackendStore::__construct()
  54          * Additional $config params include:
  55          *    swiftAuthUrl       : Swift authentication server URL
  56          *    swiftUser          : Swift user used by MediaWiki (account:username)
  57          *    swiftKey           : Swift authentication key for the above user
  58          *    swiftAuthTTL       : Swift authentication TTL (seconds)
  59          *    swiftAnonUser      : Swift user used for end-user requests (account:username)
  60          *    swiftUseCDN        : Whether a Cloud Files Content Delivery Network is set up
  61          *    shardViaHashLevels : Map of container names to sharding config with:
  62          *                         'base'   : base of hash characters, 16 or 36
  63          *                         'levels' : the number of hash levels (and digits)
  64          *                         'repeat' : hash subdirectories are prefixed with all the
  65          *                                    parent hash directory names (e.g. "a/ab/abc")
  66          */
  67         public function __construct( array $config ) {
  68                 parent::__construct( $config );
  69                 if ( !MWInit::classExists( 'CF_Constants' ) ) {
  70                         throw new MWException( 'SwiftCloudFiles extension not installed.' );
  71                 }
  72                 // Required settings
  73                 $this->auth = new CF_Authentication(
  74                         $config['swiftUser'],
  75                         $config['swiftKey'],
  76                         null, // account; unused
  77                         $config['swiftAuthUrl']
  78                 );
  79                 // Optional settings
  80                 $this->authTTL = isset( $config['swiftAuthTTL'] )
  81                         ? $config['swiftAuthTTL']
  82                         : 5 * 60; // some sane number
  83                 $this->swiftAnonUser = isset( $config['swiftAnonUser'] )
  84                         ? $config['swiftAnonUser']
  85                         : '';
  86                 $this->shardViaHashLevels = isset( $config['shardViaHashLevels'] )
  87                         ? $config['shardViaHashLevels']
  88                         : '';
  89                 $this->swiftUseCDN = isset( $config['swiftUseCDN'] )
  90                         ? $config['swiftUseCDN']
  91                         : false;
  92                 // Cache container info to mask latency
  93                 $this->memCache = wfGetMainCache();
  94         }
  95
  96         /**
  97          * @see FileBackendStore::resolveContainerPath()
  98          * @return null
  99          */
 100         protected function resolveContainerPath( $container, $relStoragePath ) {
 101                 if ( strlen( urlencode( $relStoragePath ) ) > 1024 ) {
 102                         return null; // too long for Swift
 103                 }
 104                 return $relStoragePath;
 105         }
 106
 107         /**
 108          * @see FileBackendStore::isPathUsableInternal()
 109          * @return bool
 110          */
 111         public function isPathUsableInternal( $storagePath ) {
 112                 list( $container, $rel ) = $this->resolveStoragePathReal( $storagePath );
 113                 if ( $rel === null ) {
 114                         return false; // invalid
 115                 }
 116
 117                 try {
 118                         $this->getContainer( $container );
 119                         return true; // container exists
 120                 } catch ( NoSuchContainerException $e ) {
 121                 } catch ( CloudFilesException $e ) { // some other exception?
 122                         $this->handleException( $e, null, __METHOD__, array( 'path' => $storagePath ) );
 123                 }
 124
 125                 return false;
 126         }
 127
 128         /**
 129          * @see FileBackendStore::doCreateInternal()
 130          * @return Status
 131          */
 132         protected function doCreateInternal( array $params ) {
 133                 $status = Status::newGood();
 134
 135                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 136                 if ( $dstRel === null ) {
 137                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 138                         return $status;
 139                 }
 140
 141                 // (a) Check the destination container and object
 142                 try {
 143                         $dContObj = $this->getContainer( $dstCont );
 144                         if ( empty( $params['overwrite'] ) &&
 145                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 146                         {
 147                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 148                                 return $status;
 149                         }
 150                 } catch ( NoSuchContainerException $e ) {
 151                         $status->fatal( 'backend-fail-create', $params['dst'] );
 152                         return $status;
 153                 } catch ( CloudFilesException $e ) { // some other exception?
 154                         $this->handleException( $e, $status, __METHOD__, $params );
 155                         return $status;
 156                 }
 157
 158                 // (b) Get a SHA-1 hash of the object
 159                 $sha1Hash = wfBaseConvert( sha1( $params['content'] ), 16, 36, 31 );
 160
 161                 // (c) Actually create the object
 162                 try {
 163                         // Create a fresh CF_Object with no fields preloaded.
 164                         // We don't want to preserve headers, metadata, and such.
 165                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 166                         // Note: metadata keys stored as [Upper case char][[Lower case char]...]
 167                         $obj->metadata = array( 'Sha1base36' => $sha1Hash );
 168                         // Manually set the ETag (https://github.com/rackspace/php-cloudfiles/issues/59).
 169                         // The MD5 here will be checked within Swift against its own MD5.
 170                         $obj->set_etag( md5( $params['content'] ) );
 171                         // Use the same content type as StreamFile for security
 172                         $obj->content_type = StreamFile::contentTypeFromPath( $params['dst'] );
 173                         if ( !empty( $params['async'] ) ) { // deferred
 174                                 $handle = $obj->write_async( $params['content'] );
 175                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Create', $handle );
 176                                 $status->value->affectedObjects[] = $obj;
 177                         } else { // actually write the object in Swift
 178                                 $obj->write( $params['content'] );
 179                                 $this->purgeCDNCache( array( $obj ) );
 180                         }
 181                 } catch ( CDNNotEnabledException $e ) {
 182                         // CDN not enabled; nothing to see here
 183                 } catch ( BadContentTypeException $e ) {
 184                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 185                 } catch ( CloudFilesException $e ) { // some other exception?
 186                         $this->handleException( $e, $status, __METHOD__, $params );
 187                 }
 188
 189                 return $status;
 190         }
 191
 192         /**
 193          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 194          */
 195         protected function _getResponseCreate( CF_Async_Op $cfOp, Status $status, array $params ) {
 196                 try {
 197                         $cfOp->getLastResponse();
 198                 } catch ( BadContentTypeException $e ) {
 199                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 200                 }
 201         }
 202
 203         /**
 204          * @see FileBackendStore::doStoreInternal()
 205          * @return Status
 206          */
 207         protected function doStoreInternal( array $params ) {
 208                 $status = Status::newGood();
 209
 210                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 211                 if ( $dstRel === null ) {
 212                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 213                         return $status;
 214                 }
 215
 216                 // (a) Check the destination container and object
 217                 try {
 218                         $dContObj = $this->getContainer( $dstCont );
 219                         if ( empty( $params['overwrite'] ) &&
 220                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 221                         {
 222                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 223                                 return $status;
 224                         }
 225                 } catch ( NoSuchContainerException $e ) {
 226                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 227                         return $status;
 228                 } catch ( CloudFilesException $e ) { // some other exception?
 229                         $this->handleException( $e, $status, __METHOD__, $params );
 230                         return $status;
 231                 }
 232
 233                 // (b) Get a SHA-1 hash of the object
 234                 $sha1Hash = sha1_file( $params['src'] );
 235                 if ( $sha1Hash === false ) { // source doesn't exist?
 236                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 237                         return $status;
 238                 }
 239                 $sha1Hash = wfBaseConvert( $sha1Hash, 16, 36, 31 );
 240
 241                 // (c) Actually store the object
 242                 try {
 243                         // Create a fresh CF_Object with no fields preloaded.
 244                         // We don't want to preserve headers, metadata, and such.
 245                         $obj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 246                         // Note: metadata keys stored as [Upper case char][[Lower case char]...]
 247                         $obj->metadata = array( 'Sha1base36' => $sha1Hash );
 248                         // The MD5 here will be checked within Swift against its own MD5.
 249                         $obj->set_etag( md5_file( $params['src'] ) );
 250                         // Use the same content type as StreamFile for security
 251                         $obj->content_type = StreamFile::contentTypeFromPath( $params['dst'] );
 252                         if ( !empty( $params['async'] ) ) { // deferred
 253                                 wfSuppressWarnings();
 254                                 $fp = fopen( $params['src'], 'rb' );
 255                                 wfRestoreWarnings();
 256                                 if ( !$fp ) {
 257                                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 258                                 } else {
 259                                         $handle = $obj->write_async( $fp, filesize( $params['src'] ), true );
 260                                         $status->value = new SwiftFileOpHandle( $this, $params, 'Store', $handle );
 261                                         $status->value->resourcesToClose[] = $fp;
 262                                         $status->value->affectedObjects[] = $obj;
 263                                 }
 264                         } else { // actually write the object in Swift
 265                                 $obj->load_from_filename( $params['src'], true ); // calls $obj->write()
 266                                 $this->purgeCDNCache( array( $obj ) );
 267                         }
 268                 } catch ( CDNNotEnabledException $e ) {
 269                         // CDN not enabled; nothing to see here
 270                 } catch ( BadContentTypeException $e ) {
 271                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 272                 } catch ( IOException $e ) {
 273                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 274                 } catch ( CloudFilesException $e ) { // some other exception?
 275                         $this->handleException( $e, $status, __METHOD__, $params );
 276                 }
 277
 278                 return $status;
 279         }
 280
 281         /**
 282          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 283          */
 284         protected function _getResponseStore( CF_Async_Op $cfOp, Status $status, array $params ) {
 285                 try {
 286                         $cfOp->getLastResponse();
 287                 } catch ( BadContentTypeException $e ) {
 288                         $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 289                 } catch ( IOException $e ) {
 290                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 291                 }
 292         }
 293
 294         /**
 295          * @see FileBackendStore::doCopyInternal()
 296          * @return Status
 297          */
 298         protected function doCopyInternal( array $params ) {
 299                 $status = Status::newGood();
 300
 301                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 302                 if ( $srcRel === null ) {
 303                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 304                         return $status;
 305                 }
 306
 307                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 308                 if ( $dstRel === null ) {
 309                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 310                         return $status;
 311                 }
 312
 313                 // (a) Check the source/destination containers and destination object
 314                 try {
 315                         $sContObj = $this->getContainer( $srcCont );
 316                         $dContObj = $this->getContainer( $dstCont );
 317                         if ( empty( $params['overwrite'] ) &&
 318                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 319                         {
 320                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 321                                 return $status;
 322                         }
 323                 } catch ( NoSuchContainerException $e ) {
 324                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 325                         return $status;
 326                 } catch ( CloudFilesException $e ) { // some other exception?
 327                         $this->handleException( $e, $status, __METHOD__, $params );
 328                         return $status;
 329                 }
 330
 331                 // (b) Actually copy the file to the destination
 332                 try {
 333                         $dstObj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 334                         if ( !empty( $params['async'] ) ) { // deferred
 335                                 $handle = $sContObj->copy_object_to_async( $srcRel, $dContObj, $dstRel );
 336                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Copy', $handle );
 337                                 $status->value->affectedObjects[] = $dstObj;
 338                         } else { // actually write the object in Swift
 339                                 $sContObj->copy_object_to( $srcRel, $dContObj, $dstRel );
 340                                 $this->purgeCDNCache( array( $dstObj ) );
 341                         }
 342                 } catch ( CDNNotEnabledException $e ) {
 343                         // CDN not enabled; nothing to see here
 344                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 345                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 346                 } catch ( CloudFilesException $e ) { // some other exception?
 347                         $this->handleException( $e, $status, __METHOD__, $params );
 348                 }
 349
 350                 return $status;
 351         }
 352
 353         /**
 354          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 355          */
 356         protected function _getResponseCopy( CF_Async_Op $cfOp, Status $status, array $params ) {
 357                 try {
 358                         $cfOp->getLastResponse();
 359                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 360                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 361                 }
 362         }
 363
 364         /**
 365          * @see FileBackendStore::doMoveInternal()
 366          * @return Status
 367          */
 368         protected function doMoveInternal( array $params ) {
 369                 $status = Status::newGood();
 370
 371                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 372                 if ( $srcRel === null ) {
 373                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 374                         return $status;
 375                 }
 376
 377                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 378                 if ( $dstRel === null ) {
 379                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 380                         return $status;
 381                 }
 382
 383                 // (a) Check the source/destination containers and destination object
 384                 try {
 385                         $sContObj = $this->getContainer( $srcCont );
 386                         $dContObj = $this->getContainer( $dstCont );
 387                         if ( empty( $params['overwrite'] ) &&
 388                                 $this->fileExists( array( 'src' => $params['dst'], 'latest' => 1 ) ) )
 389                         {
 390                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 391                                 return $status;
 392                         }
 393                 } catch ( NoSuchContainerException $e ) {
 394                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 395                         return $status;
 396                 } catch ( CloudFilesException $e ) { // some other exception?
 397                         $this->handleException( $e, $status, __METHOD__, $params );
 398                         return $status;
 399                 }
 400
 401                 // (b) Actually move the file to the destination
 402                 try {
 403                         $srcObj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 404                         $dstObj = new CF_Object( $dContObj, $dstRel, false, false ); // skip HEAD
 405                         if ( !empty( $params['async'] ) ) { // deferred
 406                                 $handle = $sContObj->move_object_to_async( $srcRel, $dContObj, $dstRel );
 407                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Move', $handle );
 408                                 $status->value->affectedObjects[] = $srcObj;
 409                                 $status->value->affectedObjects[] = $dstObj;
 410                         } else { // actually write the object in Swift
 411                                 $sContObj->move_object_to( $srcRel, $dContObj, $dstRel );
 412                                 $this->purgeCDNCache( array( $srcObj, $dstObj ) );
 413                         }
 414                 } catch ( CDNNotEnabledException $e ) {
 415                         // CDN not enabled; nothing to see here
 416                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 417                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 418                 } catch ( CloudFilesException $e ) { // some other exception?
 419                         $this->handleException( $e, $status, __METHOD__, $params );
 420                 }
 421
 422                 return $status;
 423         }
 424
 425         /**
 426          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 427          */
 428         protected function _getResponseMove( CF_Async_Op $cfOp, Status $status, array $params ) {
 429                 try {
 430                         $cfOp->getLastResponse();
 431                 } catch ( NoSuchObjectException $e ) { // source object does not exist
 432                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 433                 }
 434         }
 435
 436         /**
 437          * @see FileBackendStore::doDeleteInternal()
 438          * @return Status
 439          */
 440         protected function doDeleteInternal( array $params ) {
 441                 $status = Status::newGood();
 442
 443                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 444                 if ( $srcRel === null ) {
 445                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 446                         return $status;
 447                 }
 448
 449                 try {
 450                         $sContObj = $this->getContainer( $srcCont );
 451                         $srcObj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 452                         if ( !empty( $params['async'] ) ) { // deferred
 453                                 $handle = $sContObj->delete_object_async( $srcRel );
 454                                 $status->value = new SwiftFileOpHandle( $this, $params, 'Delete', $handle );
 455                                 $status->value->affectedObjects[] = $srcObj;
 456                         } else { // actually write the object in Swift
 457                                 $sContObj->delete_object( $srcRel );
 458                                 $this->purgeCDNCache( array( $srcObj ) );
 459                         }
 460                 } catch ( CDNNotEnabledException $e ) {
 461                         // CDN not enabled; nothing to see here
 462                 } catch ( NoSuchContainerException $e ) {
 463                         $status->fatal( 'backend-fail-delete', $params['src'] );
 464                 } catch ( NoSuchObjectException $e ) {
 465                         if ( empty( $params['ignoreMissingSource'] ) ) {
 466                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 467                         }
 468                 } catch ( CloudFilesException $e ) { // some other exception?
 469                         $this->handleException( $e, $status, __METHOD__, $params );
 470                 }
 471
 472                 return $status;
 473         }
 474
 475         /**
 476          * @see SwiftFileBackend::doExecuteOpHandlesInternal()
 477          */
 478         protected function _getResponseDelete( CF_Async_Op $cfOp, Status $status, array $params ) {
 479                 try {
 480                         $cfOp->getLastResponse();
 481                 } catch ( NoSuchContainerException $e ) {
 482                         $status->fatal( 'backend-fail-delete', $params['src'] );
 483                 } catch ( NoSuchObjectException $e ) {
 484                         if ( empty( $params['ignoreMissingSource'] ) ) {
 485                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 486                         }
 487                 }
 488         }
 489
 490         /**
 491          * @see FileBackendStore::doPrepareInternal()
 492          * @return Status
 493          */
 494         protected function doPrepareInternal( $fullCont, $dir, array $params ) {
 495                 $status = Status::newGood();
 496
 497                 // (a) Check if container already exists
 498                 try {
 499                         $contObj = $this->getContainer( $fullCont );
 500                         // NoSuchContainerException not thrown: container must exist
 501                         return $status; // already exists
 502                 } catch ( NoSuchContainerException $e ) {
 503                         // NoSuchContainerException thrown: container does not exist
 504                 } catch ( CloudFilesException $e ) { // some other exception?
 505                         $this->handleException( $e, $status, __METHOD__, $params );
 506                         return $status;
 507                 }
 508
 509                 // (b) Create container as needed
 510                 try {
 511                         $contObj = $this->createContainer( $fullCont );
 512                         // Make container public to end-users...
 513                         if ( $this->swiftAnonUser != '' ) {
 514                                 $status->merge( $this->setContainerAccess(
 515                                         $contObj,
 516                                         array( $this->auth->username, $this->swiftAnonUser ), // read
 517                                         array( $this->auth->username ) // write
 518                                 ) );
 519                         }
 520                         if ( $this->swiftUseCDN ) { // Rackspace style CDN
 521                                 $contObj->make_public();
 522                         }
 523                 } catch ( CDNNotEnabledException $e ) {
 524                         // CDN not enabled; nothing to see here
 525                 } catch ( CloudFilesException $e ) { // some other exception?
 526                         $this->handleException( $e, $status, __METHOD__, $params );
 527                         return $status;
 528                 }
 529
 530                 return $status;
 531         }
 532
 533         /**
 534          * @see FileBackendStore::doSecureInternal()
 535          * @return Status
 536          */
 537         protected function doSecureInternal( $fullCont, $dir, array $params ) {
 538                 $status = Status::newGood();
 539
 540                 // Restrict container from end-users...
 541                 try {
 542                         // doPrepareInternal() should have been called,
 543                         // so the Swift container should already exist...
 544                         $contObj = $this->getContainer( $fullCont ); // normally a cache hit
 545                         // NoSuchContainerException not thrown: container must exist
 546
 547                         // Make container private to end-users...
 548                         if ( $this->swiftAnonUser != '' && !isset( $contObj->mw_wasSecured ) ) {
 549                                 $status->merge( $this->setContainerAccess(
 550                                         $contObj,
 551                                         array( $this->auth->username ), // read
 552                                         array( $this->auth->username ) // write
 553                                 ) );
 554                                 // @TODO: when php-cloudfiles supports container
 555                                 // metadata, we can make use of that to avoid RTTs
 556                                 $contObj->mw_wasSecured = true; // avoid useless RTTs
 557                         }
 558                         if ( $this->swiftUseCDN && $contObj->is_public() ) { // Rackspace style CDN
 559                                 $contObj->make_private();
 560                         }
 561                 } catch ( CDNNotEnabledException $e ) {
 562                         // CDN not enabled; nothing to see here
 563                 } catch ( CloudFilesException $e ) { // some other exception?
 564                         $this->handleException( $e, $status, __METHOD__, $params );
 565                 }
 566
 567                 return $status;
 568         }
 569
 570         /**
 571          * @see FileBackendStore::doCleanInternal()
 572          * @return Status
 573          */
 574         protected function doCleanInternal( $fullCont, $dir, array $params ) {
 575                 $status = Status::newGood();
 576
 577                 // Only containers themselves can be removed, all else is virtual
 578                 if ( $dir != '' ) {
 579                         return $status; // nothing to do
 580                 }
 581
 582                 // (a) Check the container
 583                 try {
 584                         $contObj = $this->getContainer( $fullCont, true );
 585                 } catch ( NoSuchContainerException $e ) {
 586                         return $status; // ok, nothing to do
 587                 } catch ( CloudFilesException $e ) { // some other exception?
 588                         $this->handleException( $e, $status, __METHOD__, $params );
 589                         return $status;
 590                 }
 591
 592                 // (b) Delete the container if empty
 593                 if ( $contObj->object_count == 0 ) {
 594                         try {
 595                                 $this->deleteContainer( $fullCont );
 596                         } catch ( NoSuchContainerException $e ) {
 597                                 return $status; // race?
 598                         } catch ( NonEmptyContainerException $e ) {
 599                                 return $status; // race? consistency delay?
 600                         } catch ( CloudFilesException $e ) { // some other exception?
 601                                 $this->handleException( $e, $status, __METHOD__, $params );
 602                                 return $status;
 603                         }
 604                 }
 605
 606                 return $status;
 607         }
 608
 609         /**
 610          * @see FileBackendStore::doFileExists()
 611          * @return array|bool|null
 612          */
 613         protected function doGetFileStat( array $params ) {
 614                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 615                 if ( $srcRel === null ) {
 616                         return false; // invalid storage path
 617                 }
 618
 619                 $stat = false;
 620                 try {
 621                         $contObj = $this->getContainer( $srcCont );
 622                         $srcObj = $contObj->get_object( $srcRel, $this->headersFromParams( $params ) );
 623                         $this->addMissingMetadata( $srcObj, $params['src'] );
 624                         $stat = array(
 625                                 // Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT" to TS_MW
 626                                 'mtime' => wfTimestamp( TS_MW, $srcObj->last_modified ),
 627                                 'size'  => $srcObj->content_length,
 628                                 'sha1'  => $srcObj->metadata['Sha1base36']
 629                         );
 630                 } catch ( NoSuchContainerException $e ) {
 631                 } catch ( NoSuchObjectException $e ) {
 632                 } catch ( CloudFilesException $e ) { // some other exception?
 633                         $stat = null;
 634                         $this->handleException( $e, null, __METHOD__, $params );
 635                 }
 636
 637                 return $stat;
 638         }
 639
 640         /**
 641          * Fill in any missing object metadata and save it to Swift
 642          *
 643          * @param $obj CF_Object
 644          * @param $path string Storage path to object
 645          * @return bool Success
 646          * @throws Exception cloudfiles exceptions
 647          */
 648         protected function addMissingMetadata( CF_Object $obj, $path ) {
 649                 if ( isset( $obj->metadata['Sha1base36'] ) ) {
 650                         return true; // nothing to do
 651                 }
 652                 $status = Status::newGood();
 653                 $scopeLockS = $this->getScopedFileLocks( array( $path ), LockManager::LOCK_UW, $status );
 654                 if ( $status->isOK() ) {
 655                         # Do not stat the file in getLocalCopy() to avoid infinite loops
 656                         $tmpFile = $this->getLocalCopy( array( 'src' => $path, 'latest' => 1, 'nostat' => 1 ) );
 657                         if ( $tmpFile ) {
 658                                 $hash = $tmpFile->getSha1Base36();
 659                                 if ( $hash !== false ) {
 660                                         $obj->metadata['Sha1base36'] = $hash;
 661                                         $obj->sync_metadata(); // save to Swift
 662                                         return true; // success
 663                                 }
 664                         }
 665                 }
 666                 $obj->metadata['Sha1base36'] = false;
 667                 return false; // failed
 668         }
 669
 670         /**
 671          * @see FileBackend::getFileContents()
 672          * @return bool|null|string
 673          */
 674         public function getFileContents( array $params ) {
 675                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 676                 if ( $srcRel === null ) {
 677                         return false; // invalid storage path
 678                 }
 679
 680                 if ( !$this->fileExists( $params ) ) {
 681                         return null;
 682                 }
 683
 684                 $data = false;
 685                 try {
 686                         $sContObj = $this->getContainer( $srcCont );
 687                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 688                         $data = $obj->read( $this->headersFromParams( $params ) );
 689                 } catch ( NoSuchContainerException $e ) {
 690                 } catch ( CloudFilesException $e ) { // some other exception?
 691                         $this->handleException( $e, null, __METHOD__, $params );
 692                 }
 693
 694                 return $data;
 695         }
 696
 697         /**
 698          * @see FileBackendStore::doDirectoryExists()
 699          * @return bool|null
 700          */
 701         protected function doDirectoryExists( $fullCont, $dir, array $params ) {
 702                 try {
 703                         $container = $this->getContainer( $fullCont );
 704                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
 705                         return ( count( $container->list_objects( 1, null, $prefix ) ) > 0 );
 706                 } catch ( NoSuchContainerException $e ) {
 707                         return false;
 708                 } catch ( CloudFilesException $e ) { // some other exception?
 709                         $this->handleException( $e, null, __METHOD__,
 710                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
 711                 }
 712
 713                 return null; // error
 714         }
 715
 716         /**
 717          * @see FileBackendStore::getDirectoryListInternal()
 718          * @return SwiftFileBackendDirList
 719          */
 720         public function getDirectoryListInternal( $fullCont, $dir, array $params ) {
 721                 return new SwiftFileBackendDirList( $this, $fullCont, $dir, $params );
 722         }
 723
 724         /**
 725          * @see FileBackendStore::getFileListInternal()
 726          * @return SwiftFileBackendFileList
 727          */
 728         public function getFileListInternal( $fullCont, $dir, array $params ) {
 729                 return new SwiftFileBackendFileList( $this, $fullCont, $dir, $params );
 730         }
 731
 732         /**
 733          * Do not call this function outside of SwiftFileBackendFileList
 734          *
 735          * @param $fullCont string Resolved container name
 736          * @param $dir string Resolved storage directory with no trailing slash
 737          * @param $after string|null Storage path of file to list items after
 738          * @param $limit integer Max number of items to list
 739          * @param $params Array Includes flag for 'topOnly'
 740          * @return Array List of relative paths of dirs directly under $dir
 741          */
 742         public function getDirListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 743                 $dirs = array();
 744
 745                 try {
 746                         $container = $this->getContainer( $fullCont );
 747                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
 748                         // Non-recursive: only list dirs right under $dir
 749                         if ( !empty( $params['topOnly'] ) ) {
 750                                 $objects = $container->list_objects( $limit, $after, $prefix, null, '/' );
 751                                 foreach ( $objects as $object ) { // files and dirs
 752                                         if ( substr( $object, -1 ) === '/' ) {
 753                                                 $dirs[] = $object; // directories end in '/'
 754                                         }
 755                                         $after = $object; // update last item
 756                                 }
 757                         // Recursive: list all dirs under $dir and its subdirs
 758                         } else {
 759                                 // Get directory from last item of prior page
 760                                 $lastDir = $this->getParentDir( $after ); // must be first page
 761                                 $objects = $container->list_objects( $limit, $after, $prefix );
 762                                 foreach ( $objects as $object ) { // files
 763                                         $objectDir = $this->getParentDir( $object ); // directory of object
 764                                         if ( $objectDir !== false ) { // file has a parent dir
 765                                                 // Swift stores paths in UTF-8, using binary sorting.
 766                                                 // See function "create_container_table" in common/db.py.
 767                                                 // If a directory is not "greater" than the last one,
 768                                                 // then it was already listed by the calling iterator.
 769                                                 if ( $objectDir > $lastDir ) {
 770                                                         $pDir = $objectDir;
 771                                                         do { // add dir and all its parent dirs
 772                                                                 $dirs[] = "{$pDir}/";
 773                                                                 $pDir = $this->getParentDir( $pDir );
 774                                                         } while ( $pDir !== false // sanity
 775                                                                 && $pDir > $lastDir // not done already
 776                                                                 && strlen( $pDir ) > strlen( $dir ) // within $dir
 777                                                         );
 778                                                 }
 779                                                 $lastDir = $objectDir;
 780                                         }
 781                                         $after = $object; // update last item
 782                                 }
 783                         }
 784                 } catch ( NoSuchContainerException $e ) {
 785                 } catch ( CloudFilesException $e ) { // some other exception?
 786                         $this->handleException( $e, null, __METHOD__,
 787                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
 788                 }
 789
 790                 return $dirs;
 791         }
 792
 793         protected function getParentDir( $path ) {
 794                 return ( strpos( $path, '/' ) !== false ) ? dirname( $path ) : false;
 795         }
 796
 797         /**
 798          * Do not call this function outside of SwiftFileBackendFileList
 799          *
 800          * @param $fullCont string Resolved container name
 801          * @param $dir string Resolved storage directory with no trailing slash
 802          * @param $after string|null Storage path of file to list items after
 803          * @param $limit integer Max number of items to list
 804          * @param $params Array Includes flag for 'topOnly'
 805          * @return Array List of relative paths of files under $dir
 806          */
 807         public function getFileListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 808                 $files = array();
 809
 810                 try {
 811                         $container = $this->getContainer( $fullCont );
 812                         $prefix = ( $dir == '' ) ? null : "{$dir}/";
 813                         // Non-recursive: only list files right under $dir
 814                         if ( !empty( $params['topOnly'] ) ) { // files and dirs
 815                                 $objects = $container->list_objects( $limit, $after, $prefix, null, '/' );
 816                                 foreach ( $objects as $object ) {
 817                                         if ( substr( $object, -1 ) !== '/' ) {
 818                                                 $files[] = $object; // directories end in '/'
 819                                         }
 820                                 }
 821                         // Recursive: list all files under $dir and its subdirs
 822                         } else { // files
 823                                 $files = $container->list_objects( $limit, $after, $prefix );
 824                         }
 825                         $after = end( $files ); // update last item
 826                         reset( $files ); // reset pointer
 827                 } catch ( NoSuchContainerException $e ) {
 828                 } catch ( CloudFilesException $e ) { // some other exception?
 829                         $this->handleException( $e, null, __METHOD__,
 830                                 array( 'cont' => $fullCont, 'dir' => $dir ) );
 831                 }
 832
 833                 return $files;
 834         }
 835
 836         /**
 837          * @see FileBackendStore::doGetFileSha1base36()
 838          * @return bool
 839          */
 840         protected function doGetFileSha1base36( array $params ) {
 841                 $stat = $this->getFileStat( $params );
 842                 if ( $stat ) {
 843                         return $stat['sha1'];
 844                 } else {
 845                         return false;
 846                 }
 847         }
 848
 849         /**
 850          * @see FileBackendStore::doStreamFile()
 851          * @return Status
 852          */
 853         protected function doStreamFile( array $params ) {
 854                 $status = Status::newGood();
 855
 856                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 857                 if ( $srcRel === null ) {
 858                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 859                 }
 860
 861                 try {
 862                         $cont = $this->getContainer( $srcCont );
 863                 } catch ( NoSuchContainerException $e ) {
 864                         $status->fatal( 'backend-fail-stream', $params['src'] );
 865                         return $status;
 866                 } catch ( CloudFilesException $e ) { // some other exception?
 867                         $this->handleException( $e, $status, __METHOD__, $params );
 868                         return $status;
 869                 }
 870
 871                 try {
 872                         $output = fopen( 'php://output', 'wb' );
 873                         $obj = new CF_Object( $cont, $srcRel, false, false ); // skip HEAD
 874                         $obj->stream( $output, $this->headersFromParams( $params ) );
 875                 } catch ( CloudFilesException $e ) { // some other exception?
 876                         $this->handleException( $e, $status, __METHOD__, $params );
 877                 }
 878
 879                 return $status;
 880         }
 881
 882         /**
 883          * @see FileBackendStore::getLocalCopy()
 884          * @return null|TempFSFile
 885          */
 886         public function getLocalCopy( array $params ) {
 887                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 888                 if ( $srcRel === null ) {
 889                         return null;
 890                 }
 891
 892                 # Check the recursion guard to avoid loops when filling metadata
 893                 if ( empty( $params['nostat'] ) && !$this->fileExists( $params ) ) {
 894                         return null;
 895                 }
 896
 897                 $tmpFile = null;
 898                 try {
 899                         $sContObj = $this->getContainer( $srcCont );
 900                         $obj = new CF_Object( $sContObj, $srcRel, false, false ); // skip HEAD
 901                         // Get source file extension
 902                         $ext = FileBackend::extensionFromPath( $srcRel );
 903                         // Create a new temporary file...
 904                         $tmpFile = TempFSFile::factory( wfBaseName( $srcRel ) . '_', $ext );
 905                         if ( $tmpFile ) {
 906                                 $handle = fopen( $tmpFile->getPath(), 'wb' );
 907                                 if ( $handle ) {
 908                                         $obj->stream( $handle, $this->headersFromParams( $params ) );
 909                                         fclose( $handle );
 910                                 } else {
 911                                         $tmpFile = null; // couldn't open temp file
 912                                 }
 913                         }
 914                 } catch ( NoSuchContainerException $e ) {
 915                         $tmpFile = null;
 916                 } catch ( CloudFilesException $e ) { // some other exception?
 917                         $tmpFile = null;
 918                         $this->handleException( $e, null, __METHOD__, $params );
 919                 }
 920
 921                 return $tmpFile;
 922         }
 923
 924         /**
 925          * @see FileBackendStore::directoriesAreVirtual()
 926          * @return bool
 927          */
 928         protected function directoriesAreVirtual() {
 929                 return true;
 930         }
 931
 932         /**
 933          * Get headers to send to Swift when reading a file based
 934          * on a FileBackend params array, e.g. that of getLocalCopy().
 935          * $params is currently only checked for a 'latest' flag.
 936          *
 937          * @param $params Array
 938          * @return Array
 939          */
 940         protected function headersFromParams( array $params ) {
 941                 $hdrs = array();
 942                 if ( !empty( $params['latest'] ) ) {
 943                         $hdrs[] = 'X-Newest: true';
 944                 }
 945                 return $hdrs;
 946         }
 947
 948         /**
 949          * @see FileBackendStore::doExecuteOpHandlesInternal()
 950          * @return Array List of corresponding Status objects
 951          */
 952         protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
 953                 $statuses = array();
 954
 955                 $cfOps = array(); // list of CF_Async_Op objects
 956                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
 957                         $cfOps[$index] = $fileOpHandle->cfOp;
 958                 }
 959                 $batch = new CF_Async_Op_Batch( $cfOps );
 960
 961                 $cfOps = $batch->execute();
 962                 foreach ( $cfOps as $index => $cfOp ) {
 963                         $status = Status::newGood();
 964                         try { // catch exceptions; update status
 965                                 $function = '_getResponse' . $fileOpHandles[$index]->call;
 966                                 $this->$function( $cfOp, $status, $fileOpHandles[$index]->params );
 967                                 $this->purgeCDNCache( $fileOpHandles[$index]->affectedObjects );
 968                         } catch ( CloudFilesException $e ) { // some other exception?
 969                                 $this->handleException( $e, $status,
 970                                         __CLASS__ . ":$function", $fileOpHandles[$index]->params );
 971                         }
 972                         $statuses[$index] = $status;
 973                 }
 974
 975                 foreach ( $fileOpHandles as $fileOpHandle ) {
 976                         $fileOpHandle->closeResources();
 977                 }
 978
 979                 return $statuses;
 980         }
 981
 982         /**
 983          * Set read/write permissions for a Swift container
 984          *
 985          * @param $contObj CF_Container Swift container
 986          * @param $readGrps Array Swift users who can read (account:user)
 987          * @param $writeGrps Array Swift users who can write (account:user)
 988          * @return Status
 989          */
 990         protected function setContainerAccess(
 991                 CF_Container $contObj, array $readGrps, array $writeGrps
 992         ) {
 993                 $creds = $contObj->cfs_auth->export_credentials();
 994
 995                 $url = $creds['storage_url'] . '/' . rawurlencode( $contObj->name );
 996
 997                 // Note: 10 second timeout consistent with php-cloudfiles
 998                 $req = new CurlHttpRequest( $url, array( 'method' => 'POST', 'timeout' => 10 ) );
 999                 $req->setHeader( 'X-Auth-Token', $creds['auth_token'] );
1000                 $req->setHeader( 'X-Container-Read', implode( ',', $readGrps ) );
1001                 $req->setHeader( 'X-Container-Write', implode( ',', $writeGrps ) );
1002
1003                 return $req->execute(); // should return 204
1004         }
1005
1006         /**
1007          * Purge the CDN cache of affected objects if CDN caching is enabled
1008          *
1009          * @param $objects Array List of CF_Object items
1010          * @return void
1011          */
1012         public function purgeCDNCache( array $objects ) {
1013                 if ( $this->swiftUseCDN ) { // Rackspace style CDN
1014                         foreach ( $objects as $object ) {
1015                                 try {
1016                                         $object->purge_from_cdn();
1017                                 } catch ( CDNNotEnabledException $e ) {
1018                                         // CDN not enabled; nothing to see here
1019                                 } catch ( CloudFilesException $e ) {
1020                                         $this->handleException( $e, null, __METHOD__,
1021                                                 array( 'cont' => $object->container->name, 'obj' => $object->name ) );
1022                                 }
1023                         }
1024                 }
1025         }
1026
1027         /**
1028          * Get a connection to the Swift proxy
1029          *
1030          * @return CF_Connection|bool False on failure
1031          * @throws InvalidResponseException
1032          */
1033         protected function getConnection() {
1034                 if ( $this->conn === false ) {
1035                         throw new InvalidResponseException; // failed last attempt
1036                 }
1037                 // Session keys expire after a while, so we renew them periodically
1038                 if ( $this->conn && ( time() - $this->connStarted ) > $this->authTTL ) {
1039                         $this->conn->close(); // close active cURL connections
1040                         $this->conn = null;
1041                 }
1042                 // Authenticate with proxy and get a session key...
1043                 if ( $this->conn === null ) {
1044                         $this->connContainers = array();
1045                         try {
1046                                 $this->auth->authenticate();
1047                                 $this->conn = new CF_Connection( $this->auth );
1048                                 $this->connStarted = time();
1049                         } catch ( AuthenticationException $e ) {
1050                                 $this->conn = false; // don't keep re-trying
1051                         } catch ( InvalidResponseException $e ) {
1052                                 $this->conn = false; // don't keep re-trying
1053                         }
1054                 }
1055                 if ( !$this->conn ) {
1056                         throw new InvalidResponseException; // auth/connection problem
1057                 }
1058                 return $this->conn;
1059         }
1060
1061         /**
1062          * @see FileBackendStore::doClearCache()
1063          */
1064         protected function doClearCache( array $paths = null ) {
1065                 $this->connContainers = array(); // clear container object cache
1066         }
1067
1068         /**
1069          * Get a Swift container object, possibly from process cache.
1070          * Use $reCache if the file count or byte count is needed.
1071          *
1072          * @param $container string Container name
1073          * @param $bypassCache bool Bypass all caches and load from Swift
1074          * @return CF_Container
1075          * @throws NoSuchContainerException
1076          * @throws InvalidResponseException
1077          */
1078         protected function getContainer( $container, $bypassCache = false ) {
1079                 $conn = $this->getConnection(); // Swift proxy connection
1080                 if ( $bypassCache ) { // purge cache
1081                         unset( $this->connContainers[$container] );
1082                 } elseif ( !isset( $this->connContainers[$container] ) ) {
1083                         $this->primeContainerCache( array( $container ) ); // check persistent cache
1084                 }
1085                 if ( !isset( $this->connContainers[$container] ) ) {
1086                         $contObj = $conn->get_container( $container );
1087                         // NoSuchContainerException not thrown: container must exist
1088                         if ( count( $this->connContainers ) >= $this->maxContCacheSize ) { // trim cache?
1089                                 reset( $this->connContainers );
1090                                 unset( $this->connContainers[key( $this->connContainers )] );
1091                         }
1092                         $this->connContainers[$container] = $contObj; // cache it
1093                         if ( !$bypassCache ) {
1094                                 $this->setContainerCache( $container, // update persistent cache
1095                                         array( 'bytes' => $contObj->bytes_used, 'count' => $contObj->object_count )
1096                                 );
1097                         }
1098                 }
1099                 return $this->connContainers[$container];
1100         }
1101
1102         /**
1103          * Create a Swift container
1104          *
1105          * @param $container string Container name
1106          * @return CF_Container
1107          * @throws InvalidResponseException
1108          */
1109         protected function createContainer( $container ) {
1110                 $conn = $this->getConnection(); // Swift proxy connection
1111                 $contObj = $conn->create_container( $container );
1112                 $this->connContainers[$container] = $contObj; // cache it
1113                 return $contObj;
1114         }
1115
1116         /**
1117          * Delete a Swift container
1118          *
1119          * @param $container string Container name
1120          * @return void
1121          * @throws InvalidResponseException
1122          */
1123         protected function deleteContainer( $container ) {
1124                 $conn = $this->getConnection(); // Swift proxy connection
1125                 $conn->delete_container( $container );
1126                 unset( $this->connContainers[$container] ); // purge cache
1127         }
1128
1129         /**
1130          * @see FileBackendStore::doPrimeContainerCache()
1131          * @return void
1132          */
1133         protected function doPrimeContainerCache( array $containerInfo ) {
1134                 try {
1135                         $conn = $this->getConnection(); // Swift proxy connection
1136                         foreach ( $containerInfo as $container => $info ) {
1137                                 $this->connContainers[$container] = new CF_Container(
1138                                         $conn->cfs_auth,
1139                                         $conn->cfs_http,
1140                                         $container,
1141                                         $info['count'],
1142                                         $info['bytes']
1143                                 );
1144                         }
1145                 } catch ( CloudFilesException $e ) { // some other exception?
1146                         $this->handleException( $e, null, __METHOD__, array() );
1147                 }
1148         }
1149
1150         /**
1151          * Log an unexpected exception for this backend.
1152          * This also sets the Status object to have a fatal error.
1153          *
1154          * @param $e Exception
1155          * @param $status Status|null
1156          * @param $func string
1157          * @param $params Array
1158          * @return void
1159          */
1160         protected function handleException( Exception $e, $status, $func, array $params ) {
1161                 if ( $status instanceof Status ) {
1162                         if ( $e instanceof AuthenticationException ) {
1163                                 $status->fatal( 'backend-fail-connect', $this->name );
1164                         } else {
1165                                 $status->fatal( 'backend-fail-internal', $this->name );
1166                         }
1167                 }
1168                 if ( $e->getMessage() ) {
1169                         trigger_error( "$func: " . $e->getMessage(), E_USER_WARNING );
1170                 }
1171                 wfDebugLog( 'SwiftBackend',
1172                         get_class( $e ) . " in '{$func}' (given '" . FormatJson::encode( $params ) . "')" .
1173                         ( $e->getMessage() ? ": {$e->getMessage()}" : "" )
1174                 );
1175         }
1176 }
1177
1178 /**
1179  * @see FileBackendStoreOpHandle
1180  */
1181 class SwiftFileOpHandle extends FileBackendStoreOpHandle {
1182         /** @var CF_Async_Op */
1183         public $cfOp;
1184         /** @var Array */
1185         public $affectedObjects = array();
1186
1187         public function __construct( $backend, array $params, $call, CF_Async_Op $cfOp ) {
1188                 $this->backend = $backend;
1189                 $this->params = $params;
1190                 $this->call = $call;
1191                 $this->cfOp = $cfOp;
1192         }
1193 }
1194
1195 /**
1196  * SwiftFileBackend helper class to page through listings.
1197  * Swift also has a listing limit of 10,000 objects for sanity.
1198  * Do not use this class from places outside SwiftFileBackend.
1199  *
1200  * @ingroup FileBackend
1201  */
1202 abstract class SwiftFileBackendList implements Iterator {
1203         /** @var Array */
1204         protected $bufferIter = array();
1205         protected $bufferAfter = null; // string; list items *after* this path
1206         protected $pos = 0; // integer
1207         /** @var Array */
1208         protected $params = array();
1209
1210         /** @var SwiftFileBackend */
1211         protected $backend;
1212         protected $container; // string; container name
1213         protected $dir; // string; storage directory
1214         protected $suffixStart; // integer
1215
1216         const PAGE_SIZE = 5000; // file listing buffer size
1217
1218         /**
1219          * @param $backend SwiftFileBackend
1220          * @param $fullCont string Resolved container name
1221          * @param $dir string Resolved directory relative to container
1222          * @param $params Array
1223          */
1224         public function __construct( SwiftFileBackend $backend, $fullCont, $dir, array $params ) {
1225                 $this->backend = $backend;
1226                 $this->container = $fullCont;
1227                 $this->dir = $dir;
1228                 if ( substr( $this->dir, -1 ) === '/' ) {
1229                         $this->dir = substr( $this->dir, 0, -1 ); // remove trailing slash
1230                 }
1231                 if ( $this->dir == '' ) { // whole container
1232                         $this->suffixStart = 0;
1233                 } else { // dir within container
1234                         $this->suffixStart = strlen( $this->dir ) + 1; // size of "path/to/dir/"
1235                 }
1236                 $this->params = $params;
1237         }
1238
1239         /**
1240          * @see Iterator::key()
1241          * @return integer
1242          */
1243         public function key() {
1244                 return $this->pos;
1245         }
1246
1247         /**
1248          * @see Iterator::next()
1249          * @return void
1250          */
1251         public function next() {
1252                 // Advance to the next file in the page
1253                 next( $this->bufferIter );
1254                 ++$this->pos;
1255                 // Check if there are no files left in this page and
1256                 // advance to the next page if this page was not empty.
1257                 if ( !$this->valid() && count( $this->bufferIter ) ) {
1258                         $this->bufferIter = $this->pageFromList(
1259                                 $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1260                         ); // updates $this->bufferAfter
1261                 }
1262         }
1263
1264         /**
1265          * @see Iterator::rewind()
1266          * @return void
1267          */
1268         public function rewind() {
1269                 $this->pos = 0;
1270                 $this->bufferAfter = null;
1271                 $this->bufferIter = $this->pageFromList(
1272                         $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1273                 ); // updates $this->bufferAfter
1274         }
1275
1276         /**
1277          * @see Iterator::valid()
1278          * @return bool
1279          */
1280         public function valid() {
1281                 if ( $this->bufferIter === null ) {
1282                         return false; // some failure?
1283                 } else {
1284                         return ( current( $this->bufferIter ) !== false ); // no paths can have this value
1285                 }
1286         }
1287
1288         /**
1289          * Get the given list portion (page)
1290          *
1291          * @param $container string Resolved container name
1292          * @param $dir string Resolved path relative to container
1293          * @param $after string|null
1294          * @param $limit integer
1295          * @param $params Array
1296          * @return Traversable|Array|null Returns null on failure
1297          */
1298         abstract protected function pageFromList( $container, $dir, &$after, $limit, array $params );
1299 }
1300
1301 /**
1302  * Iterator for listing directories
1303  */
1304 class SwiftFileBackendDirList extends SwiftFileBackendList {
1305         /**
1306          * @see Iterator::current()
1307          * @return string|bool String (relative path) or false
1308          */
1309         public function current() {
1310                 return substr( current( $this->bufferIter ), $this->suffixStart, -1 );
1311         }
1312
1313         /**
1314          * @see SwiftFileBackendList::pageFromList()
1315          * @return Array|null
1316          */
1317         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1318                 return $this->backend->getDirListPageInternal( $container, $dir, $after, $limit, $params );
1319         }
1320 }
1321
1322 /**
1323  * Iterator for listing regular files
1324  */
1325 class SwiftFileBackendFileList extends SwiftFileBackendList {
1326         /**
1327          * @see Iterator::current()
1328          * @return string|bool String (relative path) or false
1329          */
1330         public function current() {
1331                 return substr( current( $this->bufferIter ), $this->suffixStart );
1332         }
1333
1334         /**
1335          * @see SwiftFileBackendList::pageFromList()
1336          * @return Array|null
1337          */
1338         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1339                 return $this->backend->getFileListPageInternal( $container, $dir, $after, $limit, $params );
1340         }
1341 }