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