includes/filebackend/SwiftFileBackend.php

   1 <?php
   2 /**
   3  * OpenStack Swift based file backend.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup FileBackend
  22  * @author Russ Nelson
  23  * @author Aaron Schulz
  24  */
  25
  26 /**
  27  * @brief Class for an OpenStack Swift (or Ceph RGW) based file backend.
  28  *
  29  * Status messages should avoid mentioning the Swift account name.
  30  * Likewise, error suppression should be used to avoid path disclosure.
  31  *
  32  * @ingroup FileBackend
  33  * @since 1.19
  34  */
  35 class SwiftFileBackend extends FileBackendStore {
  36         /** @var MultiHttpClient */
  37         protected $http;
  38
  39         /** @var int TTL in seconds */
  40         protected $authTTL;
  41
  42         /** @var string Authentication base URL (without version) */
  43         protected $swiftAuthUrl;
  44
  45         /** @var string Swift user (account:user) to authenticate as */
  46         protected $swiftUser;
  47
  48         /** @var string Secret key for user */
  49         protected $swiftKey;
  50
  51         /** @var string Shared secret value for making temp URLs */
  52         protected $swiftTempUrlKey;
  53
  54         /** @var string S3 access key (RADOS Gateway) */
  55         protected $rgwS3AccessKey;
  56
  57         /** @var string S3 authentication key (RADOS Gateway) */
  58         protected $rgwS3SecretKey;
  59
  60         /** @var BagOStuff */
  61         protected $srvCache;
  62
  63         /** @var ProcessCacheLRU Container stat cache */
  64         protected $containerStatCache;
  65
  66         /** @var array */
  67         protected $authCreds;
  68
  69         /** @var int UNIX timestamp */
  70         protected $authSessionTimestamp = 0;
  71
  72         /** @var int UNIX timestamp */
  73         protected $authErrorTimestamp = null;
  74
  75         /** @var bool Whether the server is an Ceph RGW */
  76         protected $isRGW = false;
  77
  78         /**
  79          * @see FileBackendStore::__construct()
  80          * Additional $config params include:
  81          *   - swiftAuthUrl       : Swift authentication server URL
  82          *   - swiftUser          : Swift user used by MediaWiki (account:username)
  83          *   - swiftKey           : Swift authentication key for the above user
  84          *   - swiftAuthTTL       : Swift authentication TTL (seconds)
  85          *   - swiftTempUrlKey    : Swift "X-Account-Meta-Temp-URL-Key" value on the account.
  86          *                          Do not set this until it has been set in the backend.
  87          *   - shardViaHashLevels : Map of container names to sharding config with:
  88          *                             - base   : base of hash characters, 16 or 36
  89          *                             - levels : the number of hash levels (and digits)
  90          *                             - repeat : hash subdirectories are prefixed with all the
  91          *                                        parent hash directory names (e.g. "a/ab/abc")
  92          *   - cacheAuthInfo      : Whether to cache authentication tokens in APC, XCache, ect.
  93          *                          If those are not available, then the main cache will be used.
  94          *                          This is probably insecure in shared hosting environments.
  95          *   - rgwS3AccessKey     : Rados Gateway S3 "access key" value on the account.
  96          *                          Do not set this until it has been set in the backend.
  97          *                          This is used for generating expiring pre-authenticated URLs.
  98          *                          Only use this when using rgw and to work around
  99          *                          http://tracker.newdream.net/issues/3454.
 100          *   - rgwS3SecretKey     : Rados Gateway S3 "secret key" value on the account.
 101          *                          Do not set this until it has been set in the backend.
 102          *                          This is used for generating expiring pre-authenticated URLs.
 103          *                          Only use this when using rgw and to work around
 104          *                          http://tracker.newdream.net/issues/3454.
 105          */
 106         public function __construct( array $config ) {
 107                 parent::__construct( $config );
 108                 // Required settings
 109                 $this->swiftAuthUrl = $config['swiftAuthUrl'];
 110                 $this->swiftUser = $config['swiftUser'];
 111                 $this->swiftKey = $config['swiftKey'];
 112                 // Optional settings
 113                 $this->authTTL = isset( $config['swiftAuthTTL'] )
 114                         ? $config['swiftAuthTTL']
 115                         : 5 * 60; // some sane number
 116                 $this->swiftTempUrlKey = isset( $config['swiftTempUrlKey'] )
 117                         ? $config['swiftTempUrlKey']
 118                         : '';
 119                 $this->shardViaHashLevels = isset( $config['shardViaHashLevels'] )
 120                         ? $config['shardViaHashLevels']
 121                         : '';
 122                 $this->rgwS3AccessKey = isset( $config['rgwS3AccessKey'] )
 123                         ? $config['rgwS3AccessKey']
 124                         : '';
 125                 $this->rgwS3SecretKey = isset( $config['rgwS3SecretKey'] )
 126                         ? $config['rgwS3SecretKey']
 127                         : '';
 128                 // HTTP helper client
 129                 $this->http = new MultiHttpClient( array() );
 130                 // Cache container information to mask latency
 131                 $this->memCache = wfGetMainCache();
 132                 // Process cache for container info
 133                 $this->containerStatCache = new ProcessCacheLRU( 300 );
 134                 // Cache auth token information to avoid RTTs
 135                 if ( !empty( $config['cacheAuthInfo'] ) ) {
 136                         if ( PHP_SAPI === 'cli' ) {
 137                                 $this->srvCache = wfGetMainCache(); // preferrably memcached
 138                         } else {
 139                                 try { // look for APC, XCache, WinCache, ect...
 140                                         $this->srvCache = ObjectCache::newAccelerator( array() );
 141                                 } catch ( Exception $e ) {
 142                                 }
 143                         }
 144                 }
 145                 $this->srvCache = $this->srvCache ?: new EmptyBagOStuff();
 146         }
 147
 148         public function getFeatures() {
 149                 return ( FileBackend::ATTR_HEADERS | FileBackend::ATTR_METADATA );
 150         }
 151
 152         protected function resolveContainerPath( $container, $relStoragePath ) {
 153                 if ( !mb_check_encoding( $relStoragePath, 'UTF-8' ) ) { // mb_string required by CF
 154                         return null; // not UTF-8, makes it hard to use CF and the swift HTTP API
 155                 } elseif ( strlen( urlencode( $relStoragePath ) ) > 1024 ) {
 156                         return null; // too long for Swift
 157                 }
 158
 159                 return $relStoragePath;
 160         }
 161
 162         public function isPathUsableInternal( $storagePath ) {
 163                 list( $container, $rel ) = $this->resolveStoragePathReal( $storagePath );
 164                 if ( $rel === null ) {
 165                         return false; // invalid
 166                 }
 167
 168                 return is_array( $this->getContainerStat( $container ) );
 169         }
 170
 171         /**
 172          * Sanitize and filter the custom headers from a $params array.
 173          * We only allow certain Content- and X-Content- headers.
 174          *
 175          * @param array $headers
 176          * @return array Sanitized value of 'headers' field in $params
 177          */
 178         protected function sanitizeHdrs( array $params ) {
 179                 $headers = array();
 180
 181                 // Normalize casing, and strip out illegal headers
 182                 if ( isset( $params['headers'] ) ) {
 183                         foreach ( $params['headers'] as $name => $value ) {
 184                                 $name = strtolower( $name );
 185                                 if ( preg_match( '/^content-(type|length)$/', $name ) ) {
 186                                         continue; // blacklisted
 187                                 } elseif ( preg_match( '/^(x-)?content-/', $name ) ) {
 188                                         $headers[$name] = $value; // allowed
 189                                 } elseif ( preg_match( '/^content-(disposition)/', $name ) ) {
 190                                         $headers[$name] = $value; // allowed
 191                                 }
 192                         }
 193                 }
 194                 // By default, Swift has annoyingly low maximum header value limits
 195                 if ( isset( $headers['content-disposition'] ) ) {
 196                         $disposition = '';
 197                         foreach ( explode( ';', $headers['content-disposition'] ) as $part ) {
 198                                 $part = trim( $part );
 199                                 $new = ( $disposition === '' ) ? $part : "{$disposition};{$part}";
 200                                 if ( strlen( $new ) <= 255 ) {
 201                                         $disposition = $new;
 202                                 } else {
 203                                         break; // too long; sigh
 204                                 }
 205                         }
 206                         $headers['content-disposition'] = $disposition;
 207                 }
 208
 209                 return $headers;
 210         }
 211
 212         protected function doCreateInternal( array $params ) {
 213                 $status = Status::newGood();
 214
 215                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 216                 if ( $dstRel === null ) {
 217                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 218
 219                         return $status;
 220                 }
 221
 222                 $sha1Hash = wfBaseConvert( sha1( $params['content'] ), 16, 36, 31 );
 223                 $contentType = $this->getContentType( $params['dst'], $params['content'], null );
 224
 225                 $reqs = array( array(
 226                         'method' => 'PUT',
 227                         'url' => array( $dstCont, $dstRel ),
 228                         'headers' => array(
 229                                 'content-length' => strlen( $params['content'] ),
 230                                 'etag' => md5( $params['content'] ),
 231                                 'content-type' => $contentType,
 232                                 'x-object-meta-sha1base36' => $sha1Hash
 233                         ) + $this->sanitizeHdrs( $params ),
 234                         'body' => $params['content']
 235                 ) );
 236
 237                 $be = $this;
 238                 $method = __METHOD__;
 239                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 240                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 241                         if ( $rcode === 201 ) {
 242                                 // good
 243                         } elseif ( $rcode === 412 ) {
 244                                 $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 245                         } else {
 246                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 247                         }
 248                 };
 249
 250                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 251                 if ( !empty( $params['async'] ) ) { // deferred
 252                         $status->value = $opHandle;
 253                 } else { // actually write the object in Swift
 254                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 255                 }
 256
 257                 return $status;
 258         }
 259
 260         protected function doStoreInternal( array $params ) {
 261                 $status = Status::newGood();
 262
 263                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 264                 if ( $dstRel === null ) {
 265                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 266
 267                         return $status;
 268                 }
 269
 270                 wfSuppressWarnings();
 271                 $sha1Hash = sha1_file( $params['src'] );
 272                 wfRestoreWarnings();
 273                 if ( $sha1Hash === false ) { // source doesn't exist?
 274                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 275
 276                         return $status;
 277                 }
 278                 $sha1Hash = wfBaseConvert( $sha1Hash, 16, 36, 31 );
 279                 $contentType = $this->getContentType( $params['dst'], null, $params['src'] );
 280
 281                 $handle = fopen( $params['src'], 'rb' );
 282                 if ( $handle === false ) { // source doesn't exist?
 283                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 284
 285                         return $status;
 286                 }
 287
 288                 $reqs = array( array(
 289                         'method' => 'PUT',
 290                         'url' => array( $dstCont, $dstRel ),
 291                         'headers' => array(
 292                                 'content-length' => filesize( $params['src'] ),
 293                                 'etag' => md5_file( $params['src'] ),
 294                                 'content-type' => $contentType,
 295                                 'x-object-meta-sha1base36' => $sha1Hash
 296                         ) + $this->sanitizeHdrs( $params ),
 297                         'body' => $handle // resource
 298                 ) );
 299
 300                 $be = $this;
 301                 $method = __METHOD__;
 302                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 303                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 304                         if ( $rcode === 201 ) {
 305                                 // good
 306                         } elseif ( $rcode === 412 ) {
 307                                 $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 308                         } else {
 309                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 310                         }
 311                 };
 312
 313                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 314                 if ( !empty( $params['async'] ) ) { // deferred
 315                         $status->value = $opHandle;
 316                 } else { // actually write the object in Swift
 317                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 318                 }
 319
 320                 return $status;
 321         }
 322
 323         protected function doCopyInternal( array $params ) {
 324                 $status = Status::newGood();
 325
 326                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 327                 if ( $srcRel === null ) {
 328                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 329
 330                         return $status;
 331                 }
 332
 333                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 334                 if ( $dstRel === null ) {
 335                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 336
 337                         return $status;
 338                 }
 339
 340                 $reqs = array( array(
 341                         'method' => 'PUT',
 342                         'url' => array( $dstCont, $dstRel ),
 343                         'headers' => array(
 344                                 'x-copy-from' => '/' . rawurlencode( $srcCont ) .
 345                                         '/' . str_replace( "%2F", "/", rawurlencode( $srcRel ) )
 346                         ) + $this->sanitizeHdrs( $params ), // extra headers merged into object
 347                 ) );
 348
 349                 $be = $this;
 350                 $method = __METHOD__;
 351                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 352                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 353                         if ( $rcode === 201 ) {
 354                                 // good
 355                         } elseif ( $rcode === 404 ) {
 356                                 $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 357                         } else {
 358                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 359                         }
 360                 };
 361
 362                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 363                 if ( !empty( $params['async'] ) ) { // deferred
 364                         $status->value = $opHandle;
 365                 } else { // actually write the object in Swift
 366                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 367                 }
 368
 369                 return $status;
 370         }
 371
 372         protected function doMoveInternal( array $params ) {
 373                 $status = Status::newGood();
 374
 375                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 376                 if ( $srcRel === null ) {
 377                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 378
 379                         return $status;
 380                 }
 381
 382                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 383                 if ( $dstRel === null ) {
 384                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 385
 386                         return $status;
 387                 }
 388
 389                 $reqs = array(
 390                         array(
 391                                 'method' => 'PUT',
 392                                 'url' => array( $dstCont, $dstRel ),
 393                                 'headers' => array(
 394                                         'x-copy-from' => '/' . rawurlencode( $srcCont ) .
 395                                                 '/' . str_replace( "%2F", "/", rawurlencode( $srcRel ) )
 396                                 ) + $this->sanitizeHdrs( $params ) // extra headers merged into object
 397                         )
 398                 );
 399                 if ( "{$srcCont}/{$srcRel}" !== "{$dstCont}/{$dstRel}" ) {
 400                         $reqs[] = array(
 401                                 'method' => 'DELETE',
 402                                 'url' => array( $srcCont, $srcRel ),
 403                                 'headers' => array()
 404                         );
 405                 }
 406
 407                 $be = $this;
 408                 $method = __METHOD__;
 409                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 410                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 411                         if ( $request['method'] === 'PUT' && $rcode === 201 ) {
 412                                 // good
 413                         } elseif ( $request['method'] === 'DELETE' && $rcode === 204 ) {
 414                                 // good
 415                         } elseif ( $rcode === 404 ) {
 416                                 $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 417                         } else {
 418                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 419                         }
 420                 };
 421
 422                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 423                 if ( !empty( $params['async'] ) ) { // deferred
 424                         $status->value = $opHandle;
 425                 } else { // actually move the object in Swift
 426                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 427                 }
 428
 429                 return $status;
 430         }
 431
 432         protected function doDeleteInternal( array $params ) {
 433                 $status = Status::newGood();
 434
 435                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 436                 if ( $srcRel === null ) {
 437                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 438
 439                         return $status;
 440                 }
 441
 442                 $reqs = array( array(
 443                         'method' => 'DELETE',
 444                         'url' => array( $srcCont, $srcRel ),
 445                         'headers' => array()
 446                 ) );
 447
 448                 $be = $this;
 449                 $method = __METHOD__;
 450                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 451                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 452                         if ( $rcode === 204 ) {
 453                                 // good
 454                         } elseif ( $rcode === 404 ) {
 455                                 if ( empty( $params['ignoreMissingSource'] ) ) {
 456                                         $status->fatal( 'backend-fail-delete', $params['src'] );
 457                                 }
 458                         } else {
 459                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 460                         }
 461                 };
 462
 463                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 464                 if ( !empty( $params['async'] ) ) { // deferred
 465                         $status->value = $opHandle;
 466                 } else { // actually delete the object in Swift
 467                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 468                 }
 469
 470                 return $status;
 471         }
 472
 473         protected function doDescribeInternal( array $params ) {
 474                 $status = Status::newGood();
 475
 476                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 477                 if ( $srcRel === null ) {
 478                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 479
 480                         return $status;
 481                 }
 482
 483                 // Fetch the old object headers/metadata...this should be in stat cache by now
 484                 $stat = $this->getFileStat( array( 'src' => $params['src'], 'latest' => 1 ) );
 485                 if ( $stat && !isset( $stat['xattr'] ) ) { // older cache entry
 486                         $stat = $this->doGetFileStat( array( 'src' => $params['src'], 'latest' => 1 ) );
 487                 }
 488                 if ( !$stat ) {
 489                         $status->fatal( 'backend-fail-describe', $params['src'] );
 490
 491                         return $status;
 492                 }
 493
 494                 // POST clears prior headers, so we need to merge the changes in to the old ones
 495                 $metaHdrs = array();
 496                 foreach ( $stat['xattr']['metadata'] as $name => $value ) {
 497                         $metaHdrs["x-object-meta-$name"] = $value;
 498                 }
 499                 $customHdrs = $this->sanitizeHdrs( $params ) + $stat['xattr']['headers'];
 500
 501                 $reqs = array( array(
 502                         'method' => 'POST',
 503                         'url' => array( $srcCont, $srcRel ),
 504                         'headers' => $metaHdrs + $customHdrs
 505                 ) );
 506
 507                 $be = $this;
 508                 $method = __METHOD__;
 509                 $handler = function ( array $request, Status $status ) use ( $be, $method, $params ) {
 510                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 511                         if ( $rcode === 202 ) {
 512                                 // good
 513                         } elseif ( $rcode === 404 ) {
 514                                 $status->fatal( 'backend-fail-describe', $params['src'] );
 515                         } else {
 516                                 $be->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 517                         }
 518                 };
 519
 520                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 521                 if ( !empty( $params['async'] ) ) { // deferred
 522                         $status->value = $opHandle;
 523                 } else { // actually change the object in Swift
 524                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 525                 }
 526
 527                 return $status;
 528         }
 529
 530         protected function doPrepareInternal( $fullCont, $dir, array $params ) {
 531                 $status = Status::newGood();
 532
 533                 // (a) Check if container already exists
 534                 $stat = $this->getContainerStat( $fullCont );
 535                 if ( is_array( $stat ) ) {
 536                         return $status; // already there
 537                 } elseif ( $stat === null ) {
 538                         $status->fatal( 'backend-fail-internal', $this->name );
 539
 540                         return $status;
 541                 }
 542
 543                 // (b) Create container as needed with proper ACLs
 544                 if ( $stat === false ) {
 545                         $params['op'] = 'prepare';
 546                         $status->merge( $this->createContainer( $fullCont, $params ) );
 547                 }
 548
 549                 return $status;
 550         }
 551
 552         protected function doSecureInternal( $fullCont, $dir, array $params ) {
 553                 $status = Status::newGood();
 554                 if ( empty( $params['noAccess'] ) ) {
 555                         return $status; // nothing to do
 556                 }
 557
 558                 $stat = $this->getContainerStat( $fullCont );
 559                 if ( is_array( $stat ) ) {
 560                         // Make container private to end-users...
 561                         $status->merge( $this->setContainerAccess(
 562                                 $fullCont,
 563                                 array( $this->swiftUser ), // read
 564                                 array( $this->swiftUser ) // write
 565                         ) );
 566                 } elseif ( $stat === false ) {
 567                         $status->fatal( 'backend-fail-usable', $params['dir'] );
 568                 } else {
 569                         $status->fatal( 'backend-fail-internal', $this->name );
 570                 }
 571
 572                 return $status;
 573         }
 574
 575         protected function doPublishInternal( $fullCont, $dir, array $params ) {
 576                 $status = Status::newGood();
 577
 578                 $stat = $this->getContainerStat( $fullCont );
 579                 if ( is_array( $stat ) ) {
 580                         // Make container public to end-users...
 581                         $status->merge( $this->setContainerAccess(
 582                                 $fullCont,
 583                                 array( $this->swiftUser, '.r:*' ), // read
 584                                 array( $this->swiftUser ) // write
 585                         ) );
 586                 } elseif ( $stat === false ) {
 587                         $status->fatal( 'backend-fail-usable', $params['dir'] );
 588                 } else {
 589                         $status->fatal( 'backend-fail-internal', $this->name );
 590                 }
 591
 592                 return $status;
 593         }
 594
 595         protected function doCleanInternal( $fullCont, $dir, array $params ) {
 596                 $status = Status::newGood();
 597
 598                 // Only containers themselves can be removed, all else is virtual
 599                 if ( $dir != '' ) {
 600                         return $status; // nothing to do
 601                 }
 602
 603                 // (a) Check the container
 604                 $stat = $this->getContainerStat( $fullCont, true );
 605                 if ( $stat === false ) {
 606                         return $status; // ok, nothing to do
 607                 } elseif ( !is_array( $stat ) ) {
 608                         $status->fatal( 'backend-fail-internal', $this->name );
 609
 610                         return $status;
 611                 }
 612
 613                 // (b) Delete the container if empty
 614                 if ( $stat['count'] == 0 ) {
 615                         $params['op'] = 'clean';
 616                         $status->merge( $this->deleteContainer( $fullCont, $params ) );
 617                 }
 618
 619                 return $status;
 620         }
 621
 622         protected function doGetFileStat( array $params ) {
 623                 $params = array( 'srcs' => array( $params['src'] ), 'concurrency' => 1 ) + $params;
 624                 unset( $params['src'] );
 625                 $stats = $this->doGetFileStatMulti( $params );
 626
 627                 return reset( $stats );
 628         }
 629
 630         /**
 631          * Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT"/"2013-05-11T07:37:27.678360Z".
 632          * Dates might also come in like "2013-05-11T07:37:27.678360" from Swift listings,
 633          * missing the timezone suffix (though Ceph RGW does not appear to have this bug).
 634          *
 635          * @param string $ts
 636          * @param int $format Output format (TS_* constant)
 637          * @return string
 638          * @throws FileBackendError
 639          */
 640         protected function convertSwiftDate( $ts, $format = TS_MW ) {
 641                 try {
 642                         $timestamp = new MWTimestamp( $ts );
 643
 644                         return $timestamp->getTimestamp( $format );
 645                 } catch ( MWException $e ) {
 646                         throw new FileBackendError( $e->getMessage() );
 647                 }
 648         }
 649
 650         /**
 651          * Fill in any missing object metadata and save it to Swift
 652          *
 653          * @param array $objHdrs Object response headers
 654          * @param string $path Storage path to object
 655          * @return array New headers
 656          */
 657         protected function addMissingMetadata( array $objHdrs, $path ) {
 658                 if ( isset( $objHdrs['x-object-meta-sha1base36'] ) ) {
 659                         return $objHdrs; // nothing to do
 660                 }
 661
 662                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
 663                 trigger_error( "$path was not stored with SHA-1 metadata.", E_USER_WARNING );
 664
 665                 $auth = $this->getAuthentication();
 666                 if ( !$auth ) {
 667                         $objHdrs['x-object-meta-sha1base36'] = false;
 668
 669                         return $objHdrs; // failed
 670                 }
 671
 672                 $status = Status::newGood();
 673                 $scopeLockS = $this->getScopedFileLocks( array( $path ), LockManager::LOCK_UW, $status );
 674                 if ( $status->isOK() ) {
 675                         $tmpFile = $this->getLocalCopy( array( 'src' => $path, 'latest' => 1 ) );
 676                         if ( $tmpFile ) {
 677                                 $hash = $tmpFile->getSha1Base36();
 678                                 if ( $hash !== false ) {
 679                                         $objHdrs['x-object-meta-sha1base36'] = $hash;
 680                                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
 681                                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
 682                                                 'method' => 'POST',
 683                                                 'url' => $this->storageUrl( $auth, $srcCont, $srcRel ),
 684                                                 'headers' => $this->authTokenHeaders( $auth ) + $objHdrs
 685                                         ) );
 686                                         if ( $rcode >= 200 && $rcode <= 299 ) {
 687                                                 return $objHdrs; // success
 688                                         }
 689                                 }
 690                         }
 691                 }
 692                 trigger_error( "Unable to set SHA-1 metadata for $path", E_USER_WARNING );
 693                 $objHdrs['x-object-meta-sha1base36'] = false;
 694
 695                 return $objHdrs; // failed
 696         }
 697
 698         protected function doGetFileContentsMulti( array $params ) {
 699                 $contents = array();
 700
 701                 $auth = $this->getAuthentication();
 702
 703                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
 704                 // Blindly create tmp files and stream to them, catching any exception if the file does
 705                 // not exist. Doing stats here is useless and will loop infinitely in addMissingMetadata().
 706                 $reqs = array(); // (path => op)
 707
 708                 foreach ( $params['srcs'] as $path ) { // each path in this concurrent batch
 709                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
 710                         if ( $srcRel === null || !$auth ) {
 711                                 $contents[$path] = false;
 712                                 continue;
 713                         }
 714                         // Create a new temporary memory file...
 715                         $handle = fopen( 'php://temp', 'wb' );
 716                         if ( $handle ) {
 717                                 $reqs[$path] = array(
 718                                         'method'  => 'GET',
 719                                         'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
 720                                         'headers' => $this->authTokenHeaders( $auth )
 721                                                 + $this->headersFromParams( $params ),
 722                                         'stream'  => $handle,
 723                                 );
 724                         }
 725                         $contents[$path] = false;
 726                 }
 727
 728                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
 729                 $reqs = $this->http->runMulti( $reqs, $opts );
 730                 foreach ( $reqs as $path => $op ) {
 731                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $op['response'];
 732                         if ( $rcode >= 200 && $rcode <= 299 ) {
 733                                 rewind( $op['stream'] ); // start from the beginning
 734                                 $contents[$path] = stream_get_contents( $op['stream'] );
 735                         } elseif ( $rcode === 404 ) {
 736                                 $contents[$path] = false;
 737                         } else {
 738                                 $this->onError( null, __METHOD__,
 739                                         array( 'src' => $path ) + $ep, $rerr, $rcode, $rdesc );
 740                         }
 741                         fclose( $op['stream'] ); // close open handle
 742                 }
 743
 744                 return $contents;
 745         }
 746
 747         protected function doDirectoryExists( $fullCont, $dir, array $params ) {
 748                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 749                 $status = $this->objectListing( $fullCont, 'names', 1, null, $prefix );
 750                 if ( $status->isOk() ) {
 751                         return ( count( $status->value ) ) > 0;
 752                 }
 753
 754                 return null; // error
 755         }
 756
 757         /**
 758          * @see FileBackendStore::getDirectoryListInternal()
 759          * @param string $fullCont
 760          * @param string $dir
 761          * @param array $params
 762          * @return SwiftFileBackendDirList
 763          */
 764         public function getDirectoryListInternal( $fullCont, $dir, array $params ) {
 765                 return new SwiftFileBackendDirList( $this, $fullCont, $dir, $params );
 766         }
 767
 768         /**
 769          * @see FileBackendStore::getFileListInternal()
 770          * @param string $fullCont
 771          * @param string $dir
 772          * @param array $params
 773          * @return SwiftFileBackendFileList
 774          */
 775         public function getFileListInternal( $fullCont, $dir, array $params ) {
 776                 return new SwiftFileBackendFileList( $this, $fullCont, $dir, $params );
 777         }
 778
 779         /**
 780          * Do not call this function outside of SwiftFileBackendFileList
 781          *
 782          * @param string $fullCont Resolved container name
 783          * @param string $dir Resolved storage directory with no trailing slash
 784          * @param string|null $after Resolved container relative path to list items after
 785          * @param int $limit Max number of items to list
 786          * @param array $params Parameters for getDirectoryList()
 787          * @return array List of container relative resolved paths of directories directly under $dir
 788          * @throws FileBackendError
 789          */
 790         public function getDirListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 791                 $dirs = array();
 792                 if ( $after === INF ) {
 793                         return $dirs; // nothing more
 794                 }
 795
 796                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
 797
 798                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 799                 // Non-recursive: only list dirs right under $dir
 800                 if ( !empty( $params['topOnly'] ) ) {
 801                         $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix, '/' );
 802                         if ( !$status->isOk() ) {
 803                                 return $dirs; // error
 804                         }
 805                         $objects = $status->value;
 806                         foreach ( $objects as $object ) { // files and directories
 807                                 if ( substr( $object, -1 ) === '/' ) {
 808                                         $dirs[] = $object; // directories end in '/'
 809                                 }
 810                         }
 811                 } else {
 812                         // Recursive: list all dirs under $dir and its subdirs
 813                         $getParentDir = function ( $path ) {
 814                                 return ( strpos( $path, '/' ) !== false ) ? dirname( $path ) : false;
 815                         };
 816
 817                         // Get directory from last item of prior page
 818                         $lastDir = $getParentDir( $after ); // must be first page
 819                         $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix );
 820
 821                         if ( !$status->isOk() ) {
 822                                 return $dirs; // error
 823                         }
 824
 825                         $objects = $status->value;
 826
 827                         foreach ( $objects as $object ) { // files
 828                                 $objectDir = $getParentDir( $object ); // directory of object
 829
 830                                 if ( $objectDir !== false && $objectDir !== $dir ) {
 831                                         // Swift stores paths in UTF-8, using binary sorting.
 832                                         // See function "create_container_table" in common/db.py.
 833                                         // If a directory is not "greater" than the last one,
 834                                         // then it was already listed by the calling iterator.
 835                                         if ( strcmp( $objectDir, $lastDir ) > 0 ) {
 836                                                 $pDir = $objectDir;
 837                                                 do { // add dir and all its parent dirs
 838                                                         $dirs[] = "{$pDir}/";
 839                                                         $pDir = $getParentDir( $pDir );
 840                                                 } while ( $pDir !== false // sanity
 841                                                         && strcmp( $pDir, $lastDir ) > 0 // not done already
 842                                                         && strlen( $pDir ) > strlen( $dir ) // within $dir
 843                                                 );
 844                                         }
 845                                         $lastDir = $objectDir;
 846                                 }
 847                         }
 848                 }
 849                 // Page on the unfiltered directory listing (what is returned may be filtered)
 850                 if ( count( $objects ) < $limit ) {
 851                         $after = INF; // avoid a second RTT
 852                 } else {
 853                         $after = end( $objects ); // update last item
 854                 }
 855
 856                 return $dirs;
 857         }
 858
 859         /**
 860          * Do not call this function outside of SwiftFileBackendFileList
 861          *
 862          * @param string $fullCont Resolved container name
 863          * @param string $dir Resolved storage directory with no trailing slash
 864          * @param string|null $after Resolved container relative path of file to list items after
 865          * @param int $limit Max number of items to list
 866          * @param array $params Parameters for getDirectoryList()
 867          * @return array List of resolved container relative paths of files under $dir
 868          * @throws FileBackendError
 869          */
 870         public function getFileListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 871                 $files = array(); // list of (path, stat array or null) entries
 872                 if ( $after === INF ) {
 873                         return $files; // nothing more
 874                 }
 875
 876                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
 877
 878                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 879                 // $objects will contain a list of unfiltered names or CF_Object items
 880                 // Non-recursive: only list files right under $dir
 881                 if ( !empty( $params['topOnly'] ) ) {
 882                         if ( !empty( $params['adviseStat'] ) ) {
 883                                 $status = $this->objectListing( $fullCont, 'info', $limit, $after, $prefix, '/' );
 884                         } else {
 885                                 $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix, '/' );
 886                         }
 887                 } else {
 888                         // Recursive: list all files under $dir and its subdirs
 889                         if ( !empty( $params['adviseStat'] ) ) {
 890                                 $status = $this->objectListing( $fullCont, 'info', $limit, $after, $prefix );
 891                         } else {
 892                                 $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix );
 893                         }
 894                 }
 895
 896                 // Reformat this list into a list of (name, stat array or null) entries
 897                 if ( !$status->isOk() ) {
 898                         return $files; // error
 899                 }
 900
 901                 $objects = $status->value;
 902                 $files = $this->buildFileObjectListing( $params, $dir, $objects );
 903
 904                 // Page on the unfiltered object listing (what is returned may be filtered)
 905                 if ( count( $objects ) < $limit ) {
 906                         $after = INF; // avoid a second RTT
 907                 } else {
 908                         $after = end( $objects ); // update last item
 909                         $after = is_object( $after ) ? $after->name : $after;
 910                 }
 911
 912                 return $files;
 913         }
 914
 915         /**
 916          * Build a list of file objects, filtering out any directories
 917          * and extracting any stat info if provided in $objects (for CF_Objects)
 918          *
 919          * @param array $params Parameters for getDirectoryList()
 920          * @param string $dir Resolved container directory path
 921          * @param array $objects List of CF_Object items or object names
 922          * @return array List of (names,stat array or null) entries
 923          */
 924         private function buildFileObjectListing( array $params, $dir, array $objects ) {
 925                 $names = array();
 926                 foreach ( $objects as $object ) {
 927                         if ( is_object( $object ) ) {
 928                                 if ( isset( $object->subdir ) || !isset( $object->name ) ) {
 929                                         continue; // virtual directory entry; ignore
 930                                 }
 931                                 $stat = array(
 932                                         // Convert various random Swift dates to TS_MW
 933                                         'mtime'  => $this->convertSwiftDate( $object->last_modified, TS_MW ),
 934                                         'size'   => (int)$object->bytes,
 935                                         // Note: manifiest ETags are not an MD5 of the file
 936                                         'md5'    => ctype_xdigit( $object->hash ) ? $object->hash : null,
 937                                         'latest' => false // eventually consistent
 938                                 );
 939                                 $names[] = array( $object->name, $stat );
 940                         } elseif ( substr( $object, -1 ) !== '/' ) {
 941                                 // Omit directories, which end in '/' in listings
 942                                 $names[] = array( $object, null );
 943                         }
 944                 }
 945
 946                 return $names;
 947         }
 948
 949         /**
 950          * Do not call this function outside of SwiftFileBackendFileList
 951          *
 952          * @param string $path Storage path
 953          * @param array $val Stat value
 954          */
 955         public function loadListingStatInternal( $path, array $val ) {
 956                 $this->cheapCache->set( $path, 'stat', $val );
 957         }
 958
 959         protected function doGetFileXAttributes( array $params ) {
 960                 $stat = $this->getFileStat( $params );
 961                 if ( $stat ) {
 962                         if ( !isset( $stat['xattr'] ) ) {
 963                                 // Stat entries filled by file listings don't include metadata/headers
 964                                 $this->clearCache( array( $params['src'] ) );
 965                                 $stat = $this->getFileStat( $params );
 966                         }
 967
 968                         return $stat['xattr'];
 969                 } else {
 970                         return false;
 971                 }
 972         }
 973
 974         protected function doGetFileSha1base36( array $params ) {
 975                 $stat = $this->getFileStat( $params );
 976                 if ( $stat ) {
 977                         if ( !isset( $stat['sha1'] ) ) {
 978                                 // Stat entries filled by file listings don't include SHA1
 979                                 $this->clearCache( array( $params['src'] ) );
 980                                 $stat = $this->getFileStat( $params );
 981                         }
 982
 983                         return $stat['sha1'];
 984                 } else {
 985                         return false;
 986                 }
 987         }
 988
 989         protected function doStreamFile( array $params ) {
 990                 $status = Status::newGood();
 991
 992                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 993                 if ( $srcRel === null ) {
 994                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 995                 }
 996
 997                 $auth = $this->getAuthentication();
 998                 if ( !$auth || !is_array( $this->getContainerStat( $srcCont ) ) ) {
 999                         $status->fatal( 'backend-fail-stream', $params['src'] );
1000
1001                         return $status;
1002                 }
1003
1004                 $handle = fopen( 'php://output', 'wb' );
1005
1006                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1007                         'method' => 'GET',
1008                         'url' => $this->storageUrl( $auth, $srcCont, $srcRel ),
1009                         'headers' => $this->authTokenHeaders( $auth )
1010                                 + $this->headersFromParams( $params ),
1011                         'stream' => $handle,
1012                 ) );
1013
1014                 if ( $rcode >= 200 && $rcode <= 299 ) {
1015                         // good
1016                 } elseif ( $rcode === 404 ) {
1017                         $status->fatal( 'backend-fail-stream', $params['src'] );
1018                 } else {
1019                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1020                 }
1021
1022                 return $status;
1023         }
1024
1025         protected function doGetLocalCopyMulti( array $params ) {
1026                 $tmpFiles = array();
1027
1028                 $auth = $this->getAuthentication();
1029
1030                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
1031                 // Blindly create tmp files and stream to them, catching any exception if the file does
1032                 // not exist. Doing a stat here is useless causes infinite loops in addMissingMetadata().
1033                 $reqs = array(); // (path => op)
1034
1035                 foreach ( $params['srcs'] as $path ) { // each path in this concurrent batch
1036                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
1037                         if ( $srcRel === null || !$auth ) {
1038                                 $tmpFiles[$path] = null;
1039                                 continue;
1040                         }
1041                         // Get source file extension
1042                         $ext = FileBackend::extensionFromPath( $path );
1043                         // Create a new temporary file...
1044                         $tmpFile = TempFSFile::factory( 'localcopy_', $ext );
1045                         if ( $tmpFile ) {
1046                                 $handle = fopen( $tmpFile->getPath(), 'wb' );
1047                                 if ( $handle ) {
1048                                         $reqs[$path] = array(
1049                                                 'method'  => 'GET',
1050                                                 'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
1051                                                 'headers' => $this->authTokenHeaders( $auth )
1052                                                         + $this->headersFromParams( $params ),
1053                                                 'stream'  => $handle,
1054                                         );
1055                                 } else {
1056                                         $tmpFile = null;
1057                                 }
1058                         }
1059                         $tmpFiles[$path] = $tmpFile;
1060                 }
1061
1062                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
1063                 $reqs = $this->http->runMulti( $reqs, $opts );
1064                 foreach ( $reqs as $path => $op ) {
1065                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $op['response'];
1066                         fclose( $op['stream'] ); // close open handle
1067                         if ( $rcode >= 200 && $rcode <= 299
1068                                 // double check that the disk is not full/broken
1069                                 && $tmpFiles[$path]->getSize() == $rhdrs['content-length']
1070                         ) {
1071                                 // good
1072                         } elseif ( $rcode === 404 ) {
1073                                 $tmpFiles[$path] = false;
1074                         } else {
1075                                 $tmpFiles[$path] = null;
1076                                 $this->onError( null, __METHOD__,
1077                                         array( 'src' => $path ) + $ep, $rerr, $rcode, $rdesc );
1078                         }
1079                 }
1080
1081                 return $tmpFiles;
1082         }
1083
1084         public function getFileHttpUrl( array $params ) {
1085                 if ( $this->swiftTempUrlKey != '' ||
1086                         ( $this->rgwS3AccessKey != '' && $this->rgwS3SecretKey != '' )
1087                 ) {
1088                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
1089                         if ( $srcRel === null ) {
1090                                 return null; // invalid path
1091                         }
1092
1093                         $auth = $this->getAuthentication();
1094                         if ( !$auth ) {
1095                                 return null;
1096                         }
1097
1098                         $ttl = isset( $params['ttl'] ) ? $params['ttl'] : 86400;
1099                         $expires = time() + $ttl;
1100
1101                         if ( $this->swiftTempUrlKey != '' ) {
1102                                 $url = $this->storageUrl( $auth, $srcCont, $srcRel );
1103                                 // Swift wants the signature based on the unencoded object name
1104                                 $contPath = parse_url( $this->storageUrl( $auth, $srcCont ), PHP_URL_PATH );
1105                                 $signature = hash_hmac( 'sha1',
1106                                         "GET\n{$expires}\n{$contPath}/{$srcRel}",
1107                                         $this->swiftTempUrlKey
1108                                 );
1109
1110                                 return "{$url}?temp_url_sig={$signature}&temp_url_expires={$expires}";
1111                         } else { // give S3 API URL for rgw
1112                                 // Path for signature starts with the bucket
1113                                 $spath = '/' . rawurlencode( $srcCont ) . '/' .
1114                                         str_replace( '%2F', '/', rawurlencode( $srcRel ) );
1115                                 // Calculate the hash
1116                                 $signature = base64_encode( hash_hmac(
1117                                         'sha1',
1118                                         "GET\n\n\n{$expires}\n{$spath}",
1119                                         $this->rgwS3SecretKey,
1120                                         true // raw
1121                                 ) );
1122                                 // See http://s3.amazonaws.com/doc/s3-developer-guide/RESTAuthentication.html.
1123                                 // Note: adding a newline for empty CanonicalizedAmzHeaders does not work.
1124                                 return wfAppendQuery(
1125                                         str_replace( '/swift/v1', '', // S3 API is the rgw default
1126                                                 $this->storageUrl( $auth ) . $spath ),
1127                                         array(
1128                                                 'Signature' => $signature,
1129                                                 'Expires' => $expires,
1130                                                 'AWSAccessKeyId' => $this->rgwS3AccessKey )
1131                                 );
1132                         }
1133                 }
1134
1135                 return null;
1136         }
1137
1138         protected function directoriesAreVirtual() {
1139                 return true;
1140         }
1141
1142         /**
1143          * Get headers to send to Swift when reading a file based
1144          * on a FileBackend params array, e.g. that of getLocalCopy().
1145          * $params is currently only checked for a 'latest' flag.
1146          *
1147          * @param array $params
1148          * @return array
1149          */
1150         protected function headersFromParams( array $params ) {
1151                 $hdrs = array();
1152                 if ( !empty( $params['latest'] ) ) {
1153                         $hdrs['x-newest'] = 'true';
1154                 }
1155
1156                 return $hdrs;
1157         }
1158
1159         protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
1160                 $statuses = array();
1161
1162                 $auth = $this->getAuthentication();
1163                 if ( !$auth ) {
1164                         foreach ( $fileOpHandles as $index => $fileOpHandle ) {
1165                                 $statuses[$index] = Status::newFatal( 'backend-fail-connect', $this->name );
1166                         }
1167
1168                         return $statuses;
1169                 }
1170
1171                 // Split the HTTP requests into stages that can be done concurrently
1172                 $httpReqsByStage = array(); // map of (stage => index => HTTP request)
1173                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
1174                         $reqs = $fileOpHandle->httpOp;
1175                         // Convert the 'url' parameter to an actual URL using $auth
1176                         foreach ( $reqs as $stage => &$req ) {
1177                                 list( $container, $relPath ) = $req['url'];
1178                                 $req['url'] = $this->storageUrl( $auth, $container, $relPath );
1179                                 $req['headers'] = isset( $req['headers'] ) ? $req['headers'] : array();
1180                                 $req['headers'] = $this->authTokenHeaders( $auth ) + $req['headers'];
1181                                 $httpReqsByStage[$stage][$index] = $req;
1182                         }
1183                         $statuses[$index] = Status::newGood();
1184                 }
1185
1186                 // Run all requests for the first stage, then the next, and so on
1187                 $reqCount = count( $httpReqsByStage );
1188                 for ( $stage = 0; $stage < $reqCount; ++$stage ) {
1189                         $httpReqs = $this->http->runMulti( $httpReqsByStage[$stage] );
1190                         foreach ( $httpReqs as $index => $httpReq ) {
1191                                 // Run the callback for each request of this operation
1192                                 $callback = $fileOpHandles[$index]->callback;
1193                                 call_user_func_array( $callback, array( $httpReq, $statuses[$index] ) );
1194                                 // On failure, abort all remaining requests for this operation
1195                                 // (e.g. abort the DELETE request if the COPY request fails for a move)
1196                                 if ( !$statuses[$index]->isOK() ) {
1197                                         $stages = count( $fileOpHandles[$index]->httpOp );
1198                                         for ( $s = ( $stage + 1 ); $s < $stages; ++$s ) {
1199                                                 unset( $httpReqsByStage[$s][$index] );
1200                                         }
1201                                 }
1202                         }
1203                 }
1204
1205                 return $statuses;
1206         }
1207
1208         /**
1209          * Set read/write permissions for a Swift container.
1210          *
1211          * @see http://swift.openstack.org/misc.html#acls
1212          *
1213          * In general, we don't allow listings to end-users. It's not useful, isn't well-defined
1214          * (lists are truncated to 10000 item with no way to page), and is just a performance risk.
1215          *
1216          * @param string $container Resolved Swift container
1217          * @param array $readGrps List of the possible criteria for a request to have
1218          * access to read a container. Each item is one of the following formats:
1219          *   - account:user        : Grants access if the request is by the given user
1220          *   - ".r:<regex>"        : Grants access if the request is from a referrer host that
1221          *                           matches the expression and the request is not for a listing.
1222          *                           Setting this to '*' effectively makes a container public.
1223          *   -".rlistings:<regex>" : Grants access if the request is from a referrer host that
1224          *                           matches the expression and the request is for a listing.
1225          * @param array $writeGrps A list of the possible criteria for a request to have
1226          * access to write to a container. Each item is of the following format:
1227          *   - account:user       : Grants access if the request is by the given user
1228          * @return Status
1229          */
1230         protected function setContainerAccess( $container, array $readGrps, array $writeGrps ) {
1231                 $status = Status::newGood();
1232                 $auth = $this->getAuthentication();
1233
1234                 if ( !$auth ) {
1235                         $status->fatal( 'backend-fail-connect', $this->name );
1236
1237                         return $status;
1238                 }
1239
1240                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1241                         'method' => 'POST',
1242                         'url' => $this->storageUrl( $auth, $container ),
1243                         'headers' => $this->authTokenHeaders( $auth ) + array(
1244                                 'x-container-read' => implode( ',', $readGrps ),
1245                                 'x-container-write' => implode( ',', $writeGrps )
1246                         )
1247                 ) );
1248
1249                 if ( $rcode != 204 && $rcode !== 202 ) {
1250                         $status->fatal( 'backend-fail-internal', $this->name );
1251                 }
1252
1253                 return $status;
1254         }
1255
1256         /**
1257          * Get a Swift container stat array, possibly from process cache.
1258          * Use $reCache if the file count or byte count is needed.
1259          *
1260          * @param string $container Container name
1261          * @param bool $bypassCache Bypass all caches and load from Swift
1262          * @return array|bool|null False on 404, null on failure
1263          */
1264         protected function getContainerStat( $container, $bypassCache = false ) {
1265                 $section = new ProfileSection( __METHOD__ . '-' . $this->name );
1266
1267                 if ( $bypassCache ) { // purge cache
1268                         $this->containerStatCache->clear( $container );
1269                 } elseif ( !$this->containerStatCache->has( $container, 'stat' ) ) {
1270                         $this->primeContainerCache( array( $container ) ); // check persistent cache
1271                 }
1272                 if ( !$this->containerStatCache->has( $container, 'stat' ) ) {
1273                         $auth = $this->getAuthentication();
1274                         if ( !$auth ) {
1275                                 return null;
1276                         }
1277
1278                         wfProfileIn( __METHOD__ . "-{$this->name}-miss" );
1279                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1280                                 'method' => 'HEAD',
1281                                 'url' => $this->storageUrl( $auth, $container ),
1282                                 'headers' => $this->authTokenHeaders( $auth )
1283                         ) );
1284                         wfProfileOut( __METHOD__ . "-{$this->name}-miss" );
1285
1286                         if ( $rcode === 204 ) {
1287                                 $stat = array(
1288                                         'count' => $rhdrs['x-container-object-count'],
1289                                         'bytes' => $rhdrs['x-container-bytes-used']
1290                                 );
1291                                 if ( $bypassCache ) {
1292                                         return $stat;
1293                                 } else {
1294                                         $this->containerStatCache->set( $container, 'stat', $stat ); // cache it
1295                                         $this->setContainerCache( $container, $stat ); // update persistent cache
1296                                 }
1297                         } elseif ( $rcode === 404 ) {
1298                                 return false;
1299                         } else {
1300                                 $this->onError( null, __METHOD__,
1301                                         array( 'cont' => $container ), $rerr, $rcode, $rdesc );
1302
1303                                 return null;
1304                         }
1305                 }
1306
1307                 return $this->containerStatCache->get( $container, 'stat' );
1308         }
1309
1310         /**
1311          * Create a Swift container
1312          *
1313          * @param string $container Container name
1314          * @param array $params
1315          * @return Status
1316          */
1317         protected function createContainer( $container, array $params ) {
1318                 $status = Status::newGood();
1319
1320                 $auth = $this->getAuthentication();
1321                 if ( !$auth ) {
1322                         $status->fatal( 'backend-fail-connect', $this->name );
1323
1324                         return $status;
1325                 }
1326
1327                 // @see SwiftFileBackend::setContainerAccess()
1328                 if ( empty( $params['noAccess'] ) ) {
1329                         $readGrps = array( '.r:*', $this->swiftUser ); // public
1330                 } else {
1331                         $readGrps = array( $this->swiftUser ); // private
1332                 }
1333                 $writeGrps = array( $this->swiftUser ); // sanity
1334
1335                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1336                         'method' => 'PUT',
1337                         'url' => $this->storageUrl( $auth, $container ),
1338                         'headers' => $this->authTokenHeaders( $auth ) + array(
1339                                 'x-container-read' => implode( ',', $readGrps ),
1340                                 'x-container-write' => implode( ',', $writeGrps )
1341                         )
1342                 ) );
1343
1344                 if ( $rcode === 201 ) { // new
1345                         // good
1346                 } elseif ( $rcode === 202 ) { // already there
1347                         // this shouldn't really happen, but is OK
1348                 } else {
1349                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1350                 }
1351
1352                 return $status;
1353         }
1354
1355         /**
1356          * Delete a Swift container
1357          *
1358          * @param string $container Container name
1359          * @param array $params
1360          * @return Status
1361          */
1362         protected function deleteContainer( $container, array $params ) {
1363                 $status = Status::newGood();
1364
1365                 $auth = $this->getAuthentication();
1366                 if ( !$auth ) {
1367                         $status->fatal( 'backend-fail-connect', $this->name );
1368
1369                         return $status;
1370                 }
1371
1372                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1373                         'method' => 'DELETE',
1374                         'url' => $this->storageUrl( $auth, $container ),
1375                         'headers' => $this->authTokenHeaders( $auth )
1376                 ) );
1377
1378                 if ( $rcode >= 200 && $rcode <= 299 ) { // deleted
1379                         $this->containerStatCache->clear( $container ); // purge
1380                 } elseif ( $rcode === 404 ) { // not there
1381                         // this shouldn't really happen, but is OK
1382                 } elseif ( $rcode === 409 ) { // not empty
1383                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc ); // race?
1384                 } else {
1385                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1386                 }
1387
1388                 return $status;
1389         }
1390
1391         /**
1392          * Get a list of objects under a container.
1393          * Either just the names or a list of stdClass objects with details can be returned.
1394          *
1395          * @param string $fullCont
1396          * @param string $type ('info' for a list of object detail maps, 'names' for names only)
1397          * @param int $limit
1398          * @param string|null $after
1399          * @param string|null $prefix
1400          * @param string|null $delim
1401          * @return Status With the list as value
1402          */
1403         private function objectListing(
1404                 $fullCont, $type, $limit, $after = null, $prefix = null, $delim = null
1405         ) {
1406                 $status = Status::newGood();
1407
1408                 $auth = $this->getAuthentication();
1409                 if ( !$auth ) {
1410                         $status->fatal( 'backend-fail-connect', $this->name );
1411
1412                         return $status;
1413                 }
1414
1415                 $query = array( 'limit' => $limit );
1416                 if ( $type === 'info' ) {
1417                         $query['format'] = 'json';
1418                 }
1419                 if ( $after !== null ) {
1420                         $query['marker'] = $after;
1421                 }
1422                 if ( $prefix !== null ) {
1423                         $query['prefix'] = $prefix;
1424                 }
1425                 if ( $delim !== null ) {
1426                         $query['delimiter'] = $delim;
1427                 }
1428
1429                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1430                         'method' => 'GET',
1431                         'url' => $this->storageUrl( $auth, $fullCont ),
1432                         'query' => $query,
1433                         'headers' => $this->authTokenHeaders( $auth )
1434                 ) );
1435
1436                 $params = array( 'cont' => $fullCont, 'prefix' => $prefix, 'delim' => $delim );
1437                 if ( $rcode === 200 ) { // good
1438                         if ( $type === 'info' ) {
1439                                 $status->value = FormatJson::decode( trim( $rbody ) );
1440                         } else {
1441                                 $status->value = explode( "\n", trim( $rbody ) );
1442                         }
1443                 } elseif ( $rcode === 204 ) {
1444                         $status->value = array(); // empty container
1445                 } elseif ( $rcode === 404 ) {
1446                         $status->value = array(); // no container
1447                 } else {
1448                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1449                 }
1450
1451                 return $status;
1452         }
1453
1454         protected function doPrimeContainerCache( array $containerInfo ) {
1455                 foreach ( $containerInfo as $container => $info ) {
1456                         $this->containerStatCache->set( $container, 'stat', $info );
1457                 }
1458         }
1459
1460         protected function doGetFileStatMulti( array $params ) {
1461                 $stats = array();
1462
1463                 $auth = $this->getAuthentication();
1464
1465                 $reqs = array();
1466                 foreach ( $params['srcs'] as $path ) {
1467                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
1468                         if ( $srcRel === null ) {
1469                                 $stats[$path] = false;
1470                                 continue; // invalid storage path
1471                         } elseif ( !$auth ) {
1472                                 $stats[$path] = null;
1473                                 continue;
1474                         }
1475
1476                         // (a) Check the container
1477                         $cstat = $this->getContainerStat( $srcCont );
1478                         if ( $cstat === false ) {
1479                                 $stats[$path] = false;
1480                                 continue; // ok, nothing to do
1481                         } elseif ( !is_array( $cstat ) ) {
1482                                 $stats[$path] = null;
1483                                 continue;
1484                         }
1485
1486                         $reqs[$path] = array(
1487                                 'method'  => 'HEAD',
1488                                 'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
1489                                 'headers' => $this->authTokenHeaders( $auth ) + $this->headersFromParams( $params )
1490                         );
1491                 }
1492
1493                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
1494                 $reqs = $this->http->runMulti( $reqs, $opts );
1495
1496                 foreach ( $params['srcs'] as $path ) {
1497                         if ( array_key_exists( $path, $stats ) ) {
1498                                 continue; // some sort of failure above
1499                         }
1500                         // (b) Check the file
1501                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $reqs[$path]['response'];
1502                         if ( $rcode === 200 || $rcode === 204 ) {
1503                                 // Update the object if it is missing some headers
1504                                 $rhdrs = $this->addMissingMetadata( $rhdrs, $path );
1505                                 // Fetch all of the custom metadata headers
1506                                 $metadata = array();
1507                                 foreach ( $rhdrs as $name => $value ) {
1508                                         if ( strpos( $name, 'x-object-meta-' ) === 0 ) {
1509                                                 $metadata[substr( $name, strlen( 'x-object-meta-' ) )] = $value;
1510                                         }
1511                                 }
1512                                 // Fetch all of the custom raw HTTP headers
1513                                 $headers = $this->sanitizeHdrs( array( 'headers' => $rhdrs ) );
1514                                 $stat = array(
1515                                         // Convert various random Swift dates to TS_MW
1516                                         'mtime' => $this->convertSwiftDate( $rhdrs['last-modified'], TS_MW ),
1517                                         // Empty objects actually return no content-length header in Ceph
1518                                         'size'  => isset( $rhdrs['content-length'] ) ? (int)$rhdrs['content-length'] : 0,
1519                                         'sha1'  => $rhdrs[ 'x-object-meta-sha1base36'],
1520                                         // Note: manifiest ETags are not an MD5 of the file
1521                                         'md5'   => ctype_xdigit( $rhdrs['etag'] ) ? $rhdrs['etag'] : null,
1522                                         'xattr' => array( 'metadata' => $metadata, 'headers' => $headers )
1523                                 );
1524                                 if ( $this->isRGW ) {
1525                                         $stat['latest'] = true; // strong consistency
1526                                 }
1527                         } elseif ( $rcode === 404 ) {
1528                                 $stat = false;
1529                         } else {
1530                                 $stat = null;
1531                                 $this->onError( null, __METHOD__, $params, $rerr, $rcode, $rdesc );
1532                         }
1533                         $stats[$path] = $stat;
1534                 }
1535
1536                 return $stats;
1537         }
1538
1539         /**
1540          * @return array|null Credential map
1541          */
1542         protected function getAuthentication() {
1543                 if ( $this->authErrorTimestamp !== null ) {
1544                         if ( ( time() - $this->authErrorTimestamp ) < 60 ) {
1545                                 return null; // failed last attempt; don't bother
1546                         } else { // actually retry this time
1547                                 $this->authErrorTimestamp = null;
1548                         }
1549                 }
1550                 // Session keys expire after a while, so we renew them periodically
1551                 $reAuth = ( ( time() - $this->authSessionTimestamp ) > $this->authTTL );
1552                 // Authenticate with proxy and get a session key...
1553                 if ( !$this->authCreds || $reAuth ) {
1554                         $this->authSessionTimestamp = 0;
1555                         $cacheKey = $this->getCredsCacheKey( $this->swiftUser );
1556                         $creds = $this->srvCache->get( $cacheKey ); // credentials
1557                         // Try to use the credential cache
1558                         if ( isset( $creds['auth_token'] ) && isset( $creds['storage_url'] ) ) {
1559                                 $this->authCreds = $creds;
1560                                 // Skew the timestamp for worst case to avoid using stale credentials
1561                                 $this->authSessionTimestamp = time() - ceil( $this->authTTL / 2 );
1562                         } else { // cache miss
1563                                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1564                                         'method' => 'GET',
1565                                         'url' => "{$this->swiftAuthUrl}/v1.0",
1566                                         'headers' => array(
1567                                                 'x-auth-user' => $this->swiftUser,
1568                                                 'x-auth-key' => $this->swiftKey
1569                                         )
1570                                 ) );
1571
1572                                 if ( $rcode >= 200 && $rcode <= 299 ) { // OK
1573                                         $this->authCreds = array(
1574                                                 'auth_token' => $rhdrs['x-auth-token'],
1575                                                 'storage_url' => $rhdrs['x-storage-url']
1576                                         );
1577                                         $this->srvCache->set( $cacheKey, $this->authCreds, ceil( $this->authTTL / 2 ) );
1578                                         $this->authSessionTimestamp = time();
1579                                 } elseif ( $rcode === 401 ) {
1580                                         $this->onError( null, __METHOD__, array(), "Authentication failed.", $rcode );
1581                                         $this->authErrorTimestamp = time();
1582
1583                                         return null;
1584                                 } else {
1585                                         $this->onError( null, __METHOD__, array(), "HTTP return code: $rcode", $rcode );
1586                                         $this->authErrorTimestamp = time();
1587
1588                                         return null;
1589                                 }
1590                         }
1591                         // Ceph RGW does not use <account> in URLs (OpenStack Swift uses "/v1/<account>")
1592                         if ( substr( $this->authCreds['storage_url'], -3 ) === '/v1' ) {
1593                                 $this->isRGW = true; // take advantage of strong consistency
1594                         }
1595                 }
1596
1597                 return $this->authCreds;
1598         }
1599
1600         /**
1601          * @param array $creds From getAuthentication()
1602          * @param string $container
1603          * @param string $object
1604          * @return array
1605          */
1606         protected function storageUrl( array $creds, $container = null, $object = null ) {
1607                 $parts = array( $creds['storage_url'] );
1608                 if ( strlen( $container ) ) {
1609                         $parts[] = rawurlencode( $container );
1610                 }
1611                 if ( strlen( $object ) ) {
1612                         $parts[] = str_replace( "%2F", "/", rawurlencode( $object ) );
1613                 }
1614
1615                 return implode( '/', $parts );
1616         }
1617
1618         /**
1619          * @param array $creds From getAuthentication()
1620          * @return array
1621          */
1622         protected function authTokenHeaders( array $creds ) {
1623                 return array( 'x-auth-token' => $creds['auth_token'] );
1624         }
1625
1626         /**
1627          * Get the cache key for a container
1628          *
1629          * @param string $username
1630          * @return string
1631          */
1632         private function getCredsCacheKey( $username ) {
1633                 return 'swiftcredentials:' . md5( $username . ':' . $this->swiftAuthUrl );
1634         }
1635
1636         /**
1637          * Log an unexpected exception for this backend.
1638          * This also sets the Status object to have a fatal error.
1639          *
1640          * @param Status|null $status
1641          * @param string $func
1642          * @param array $params
1643          * @param string $err Error string
1644          * @param int $code HTTP status
1645          * @param string $desc HTTP status description
1646          */
1647         public function onError( $status, $func, array $params, $err = '', $code = 0, $desc = '' ) {
1648                 if ( $status instanceof Status ) {
1649                         $status->fatal( 'backend-fail-internal', $this->name );
1650                 }
1651                 if ( $code == 401 ) { // possibly a stale token
1652                         $this->srvCache->delete( $this->getCredsCacheKey( $this->swiftUser ) );
1653                 }
1654                 wfDebugLog( 'SwiftBackend',
1655                         "HTTP $code ($desc) in '{$func}' (given '" . FormatJson::encode( $params ) . "')" .
1656                         ( $err ? ": $err" : "" )
1657                 );
1658         }
1659 }
1660
1661 /**
1662  * @see FileBackendStoreOpHandle
1663  */
1664 class SwiftFileOpHandle extends FileBackendStoreOpHandle {
1665         /** @var array List of Requests for MultiHttpClient */
1666         public $httpOp;
1667         /** @var Closure */
1668         public $callback;
1669
1670         /**
1671          * @param SwiftFileBackend $backend
1672          * @param Closure $callback Function that takes (HTTP request array, status)
1673          * @param array $httpOp MultiHttpClient op
1674          */
1675         public function __construct( SwiftFileBackend $backend, Closure $callback, array $httpOp ) {
1676                 $this->backend = $backend;
1677                 $this->callback = $callback;
1678                 $this->httpOp = $httpOp;
1679         }
1680 }
1681
1682 /**
1683  * SwiftFileBackend helper class to page through listings.
1684  * Swift also has a listing limit of 10,000 objects for sanity.
1685  * Do not use this class from places outside SwiftFileBackend.
1686  *
1687  * @ingroup FileBackend
1688  */
1689 abstract class SwiftFileBackendList implements Iterator {
1690         /** @var array List of path or (path,stat array) entries */
1691         protected $bufferIter = array();
1692
1693         /** @var string List items *after* this path */
1694         protected $bufferAfter = null;
1695
1696         /** @var int */
1697         protected $pos = 0;
1698
1699         /** @var array */
1700         protected $params = array();
1701
1702         /** @var SwiftFileBackend */
1703         protected $backend;
1704
1705         /** @var string Container name */
1706         protected $container;
1707
1708         /** @var string Storage directory */
1709         protected $dir;
1710
1711         /** @var int */
1712         protected $suffixStart;
1713
1714         const PAGE_SIZE = 9000; // file listing buffer size
1715
1716         /**
1717          * @param SwiftFileBackend $backend
1718          * @param string $fullCont Resolved container name
1719          * @param string $dir Resolved directory relative to container
1720          * @param array $params
1721          */
1722         public function __construct( SwiftFileBackend $backend, $fullCont, $dir, array $params ) {
1723                 $this->backend = $backend;
1724                 $this->container = $fullCont;
1725                 $this->dir = $dir;
1726                 if ( substr( $this->dir, -1 ) === '/' ) {
1727                         $this->dir = substr( $this->dir, 0, -1 ); // remove trailing slash
1728                 }
1729                 if ( $this->dir == '' ) { // whole container
1730                         $this->suffixStart = 0;
1731                 } else { // dir within container
1732                         $this->suffixStart = strlen( $this->dir ) + 1; // size of "path/to/dir/"
1733                 }
1734                 $this->params = $params;
1735         }
1736
1737         /**
1738          * @see Iterator::key()
1739          * @return int
1740          */
1741         public function key() {
1742                 return $this->pos;
1743         }
1744
1745         /**
1746          * @see Iterator::next()
1747          */
1748         public function next() {
1749                 // Advance to the next file in the page
1750                 next( $this->bufferIter );
1751                 ++$this->pos;
1752                 // Check if there are no files left in this page and
1753                 // advance to the next page if this page was not empty.
1754                 if ( !$this->valid() && count( $this->bufferIter ) ) {
1755                         $this->bufferIter = $this->pageFromList(
1756                                 $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1757                         ); // updates $this->bufferAfter
1758                 }
1759         }
1760
1761         /**
1762          * @see Iterator::rewind()
1763          */
1764         public function rewind() {
1765                 $this->pos = 0;
1766                 $this->bufferAfter = null;
1767                 $this->bufferIter = $this->pageFromList(
1768                         $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1769                 ); // updates $this->bufferAfter
1770         }
1771
1772         /**
1773          * @see Iterator::valid()
1774          * @return bool
1775          */
1776         public function valid() {
1777                 if ( $this->bufferIter === null ) {
1778                         return false; // some failure?
1779                 } else {
1780                         return ( current( $this->bufferIter ) !== false ); // no paths can have this value
1781                 }
1782         }
1783
1784         /**
1785          * Get the given list portion (page)
1786          *
1787          * @param string $container Resolved container name
1788          * @param string $dir Resolved path relative to container
1789          * @param string $after null
1790          * @param int $limit
1791          * @param array $params
1792          * @return Traversable|array
1793          */
1794         abstract protected function pageFromList( $container, $dir, &$after, $limit, array $params );
1795 }
1796
1797 /**
1798  * Iterator for listing directories
1799  */
1800 class SwiftFileBackendDirList extends SwiftFileBackendList {
1801         /**
1802          * @see Iterator::current()
1803          * @return string|bool String (relative path) or false
1804          */
1805         public function current() {
1806                 return substr( current( $this->bufferIter ), $this->suffixStart, -1 );
1807         }
1808
1809         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1810                 return $this->backend->getDirListPageInternal( $container, $dir, $after, $limit, $params );
1811         }
1812 }
1813
1814 /**
1815  * Iterator for listing regular files
1816  */
1817 class SwiftFileBackendFileList extends SwiftFileBackendList {
1818         /**
1819          * @see Iterator::current()
1820          * @return string|bool String (relative path) or false
1821          */
1822         public function current() {
1823                 list( $path, $stat ) = current( $this->bufferIter );
1824                 $relPath = substr( $path, $this->suffixStart );
1825                 if ( is_array( $stat ) ) {
1826                         $storageDir = rtrim( $this->params['dir'], '/' );
1827                         $this->backend->loadListingStatInternal( "$storageDir/$relPath", $stat );
1828                 }
1829
1830                 return $relPath;
1831         }
1832
1833         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1834                 return $this->backend->getFileListPageInternal( $container, $dir, $after, $limit, $params );
1835         }
1836 }