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                         : 15 * 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                 if ( isset( $config['wanCache'] ) && $config['wanCache'] instanceof WANObjectCache ) {
 132                         $this->memCache = $config['wanCache'];
 133                 }
 134                 // Process cache for container info
 135                 $this->containerStatCache = new ProcessCacheLRU( 300 );
 136                 // Cache auth token information to avoid RTTs
 137                 if ( !empty( $config['cacheAuthInfo'] ) ) {
 138                         if ( PHP_SAPI === 'cli' ) {
 139                                 // Preferrably memcached
 140                                 $this->srvCache = ObjectCache::getLocalClusterInstance();
 141                         } else {
 142                                 // Look for APC, XCache, WinCache, ect...
 143                                 $this->srvCache = ObjectCache::getLocalServerInstance( CACHE_NONE );
 144                         }
 145                 } else {
 146                         $this->srvCache = new EmptyBagOStuff();
 147                 }
 148         }
 149
 150         public function getFeatures() {
 151                 return ( FileBackend::ATTR_UNICODE_PATHS |
 152                         FileBackend::ATTR_HEADERS | FileBackend::ATTR_METADATA );
 153         }
 154
 155         protected function resolveContainerPath( $container, $relStoragePath ) {
 156                 if ( !mb_check_encoding( $relStoragePath, 'UTF-8' ) ) { // mb_string required by CF
 157                         return null; // not UTF-8, makes it hard to use CF and the swift HTTP API
 158                 } elseif ( strlen( urlencode( $relStoragePath ) ) > 1024 ) {
 159                         return null; // too long for Swift
 160                 }
 161
 162                 return $relStoragePath;
 163         }
 164
 165         public function isPathUsableInternal( $storagePath ) {
 166                 list( $container, $rel ) = $this->resolveStoragePathReal( $storagePath );
 167                 if ( $rel === null ) {
 168                         return false; // invalid
 169                 }
 170
 171                 return is_array( $this->getContainerStat( $container ) );
 172         }
 173
 174         /**
 175          * Sanitize and filter the custom headers from a $params array.
 176          * Only allows certain "standard" Content- and X-Content- headers.
 177          *
 178          * @param array $params
 179          * @return array Sanitized value of 'headers' field in $params
 180          */
 181         protected function sanitizeHdrs( array $params ) {
 182                 return isset( $params['headers'] )
 183                         ? $this->getCustomHeaders( $params['headers'] )
 184                         : array();
 185
 186         }
 187
 188         /**
 189          * @param array $rawHeaders
 190          * @return array Custom non-metadata HTTP headers
 191          */
 192         protected function getCustomHeaders( array $rawHeaders ) {
 193                 $headers = array();
 194
 195                 // Normalize casing, and strip out illegal headers
 196                 foreach ( $rawHeaders as $name => $value ) {
 197                         $name = strtolower( $name );
 198                         if ( preg_match( '/^content-(type|length)$/', $name ) ) {
 199                                 continue; // blacklisted
 200                         } elseif ( preg_match( '/^(x-)?content-/', $name ) ) {
 201                                 $headers[$name] = $value; // allowed
 202                         } elseif ( preg_match( '/^content-(disposition)/', $name ) ) {
 203                                 $headers[$name] = $value; // allowed
 204                         }
 205                 }
 206                 // By default, Swift has annoyingly low maximum header value limits
 207                 if ( isset( $headers['content-disposition'] ) ) {
 208                         $disposition = '';
 209                         // @note: assume FileBackend::makeContentDisposition() already used
 210                         foreach ( explode( ';', $headers['content-disposition'] ) as $part ) {
 211                                 $part = trim( $part );
 212                                 $new = ( $disposition === '' ) ? $part : "{$disposition};{$part}";
 213                                 if ( strlen( $new ) <= 255 ) {
 214                                         $disposition = $new;
 215                                 } else {
 216                                         break; // too long; sigh
 217                                 }
 218                         }
 219                         $headers['content-disposition'] = $disposition;
 220                 }
 221
 222                 return $headers;
 223         }
 224
 225         /**
 226          * @param array $rawHeaders
 227          * @return array Custom metadata headers
 228          */
 229         protected function getMetadataHeaders( array $rawHeaders ) {
 230                 $headers = array();
 231                 foreach ( $rawHeaders as $name => $value ) {
 232                         $name = strtolower( $name );
 233                         if ( strpos( $name, 'x-object-meta-' ) === 0 ) {
 234                                 $headers[$name] = $value;
 235                         }
 236                 }
 237
 238                 return $headers;
 239         }
 240
 241         /**
 242          * @param array $rawHeaders
 243          * @return array Custom metadata headers with prefix removed
 244          */
 245         protected function getMetadata( array $rawHeaders ) {
 246                 $metadata = array();
 247                 foreach ( $this->getMetadataHeaders( $rawHeaders ) as $name => $value ) {
 248                         $metadata[substr( $name, strlen( 'x-object-meta-' ) )] = $value;
 249                 }
 250
 251                 return $metadata;
 252         }
 253
 254         protected function doCreateInternal( array $params ) {
 255                 $status = Status::newGood();
 256
 257                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 258                 if ( $dstRel === null ) {
 259                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 260
 261                         return $status;
 262                 }
 263
 264                 $sha1Hash = Wikimedia\base_convert( sha1( $params['content'] ), 16, 36, 31 );
 265                 $contentType = isset( $params['headers']['content-type'] )
 266                         ? $params['headers']['content-type']
 267                         : $this->getContentType( $params['dst'], $params['content'], null );
 268
 269                 $reqs = array( array(
 270                         'method' => 'PUT',
 271                         'url' => array( $dstCont, $dstRel ),
 272                         'headers' => array(
 273                                 'content-length' => strlen( $params['content'] ),
 274                                 'etag' => md5( $params['content'] ),
 275                                 'content-type' => $contentType,
 276                                 'x-object-meta-sha1base36' => $sha1Hash
 277                         ) + $this->sanitizeHdrs( $params ),
 278                         'body' => $params['content']
 279                 ) );
 280
 281                 $that = $this;
 282                 $method = __METHOD__;
 283                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 284                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 285                         if ( $rcode === 201 ) {
 286                                 // good
 287                         } elseif ( $rcode === 412 ) {
 288                                 $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 289                         } else {
 290                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 291                         }
 292                 };
 293
 294                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 295                 if ( !empty( $params['async'] ) ) { // deferred
 296                         $status->value = $opHandle;
 297                 } else { // actually write the object in Swift
 298                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 299                 }
 300
 301                 return $status;
 302         }
 303
 304         protected function doStoreInternal( array $params ) {
 305                 $status = Status::newGood();
 306
 307                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 308                 if ( $dstRel === null ) {
 309                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 310
 311                         return $status;
 312                 }
 313
 314                 MediaWiki\suppressWarnings();
 315                 $sha1Hash = sha1_file( $params['src'] );
 316                 MediaWiki\restoreWarnings();
 317                 if ( $sha1Hash === false ) { // source doesn't exist?
 318                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 319
 320                         return $status;
 321                 }
 322                 $sha1Hash = Wikimedia\base_convert( $sha1Hash, 16, 36, 31 );
 323                 $contentType = isset( $params['headers']['content-type'] )
 324                         ? $params['headers']['content-type']
 325                         : $this->getContentType( $params['dst'], null, $params['src'] );
 326
 327                 $handle = fopen( $params['src'], 'rb' );
 328                 if ( $handle === false ) { // source doesn't exist?
 329                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 330
 331                         return $status;
 332                 }
 333
 334                 $reqs = array( array(
 335                         'method' => 'PUT',
 336                         'url' => array( $dstCont, $dstRel ),
 337                         'headers' => array(
 338                                 'content-length' => filesize( $params['src'] ),
 339                                 'etag' => md5_file( $params['src'] ),
 340                                 'content-type' => $contentType,
 341                                 'x-object-meta-sha1base36' => $sha1Hash
 342                         ) + $this->sanitizeHdrs( $params ),
 343                         'body' => $handle // resource
 344                 ) );
 345
 346                 $that = $this;
 347                 $method = __METHOD__;
 348                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 349                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 350                         if ( $rcode === 201 ) {
 351                                 // good
 352                         } elseif ( $rcode === 412 ) {
 353                                 $status->fatal( 'backend-fail-contenttype', $params['dst'] );
 354                         } else {
 355                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 356                         }
 357                 };
 358
 359                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 360                 if ( !empty( $params['async'] ) ) { // deferred
 361                         $status->value = $opHandle;
 362                 } else { // actually write the object in Swift
 363                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 364                 }
 365
 366                 return $status;
 367         }
 368
 369         protected function doCopyInternal( array $params ) {
 370                 $status = Status::newGood();
 371
 372                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 373                 if ( $srcRel === null ) {
 374                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 375
 376                         return $status;
 377                 }
 378
 379                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 380                 if ( $dstRel === null ) {
 381                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 382
 383                         return $status;
 384                 }
 385
 386                 $reqs = array( array(
 387                         'method' => 'PUT',
 388                         'url' => array( $dstCont, $dstRel ),
 389                         'headers' => array(
 390                                 'x-copy-from' => '/' . rawurlencode( $srcCont ) .
 391                                         '/' . str_replace( "%2F", "/", rawurlencode( $srcRel ) )
 392                         ) + $this->sanitizeHdrs( $params ), // extra headers merged into object
 393                 ) );
 394
 395                 $that = $this;
 396                 $method = __METHOD__;
 397                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 398                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 399                         if ( $rcode === 201 ) {
 400                                 // good
 401                         } elseif ( $rcode === 404 ) {
 402                                 $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 403                         } else {
 404                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 405                         }
 406                 };
 407
 408                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 409                 if ( !empty( $params['async'] ) ) { // deferred
 410                         $status->value = $opHandle;
 411                 } else { // actually write the object in Swift
 412                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 413                 }
 414
 415                 return $status;
 416         }
 417
 418         protected function doMoveInternal( array $params ) {
 419                 $status = Status::newGood();
 420
 421                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 422                 if ( $srcRel === null ) {
 423                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 424
 425                         return $status;
 426                 }
 427
 428                 list( $dstCont, $dstRel ) = $this->resolveStoragePathReal( $params['dst'] );
 429                 if ( $dstRel === null ) {
 430                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 431
 432                         return $status;
 433                 }
 434
 435                 $reqs = array(
 436                         array(
 437                                 'method' => 'PUT',
 438                                 'url' => array( $dstCont, $dstRel ),
 439                                 'headers' => array(
 440                                         'x-copy-from' => '/' . rawurlencode( $srcCont ) .
 441                                                 '/' . str_replace( "%2F", "/", rawurlencode( $srcRel ) )
 442                                 ) + $this->sanitizeHdrs( $params ) // extra headers merged into object
 443                         )
 444                 );
 445                 if ( "{$srcCont}/{$srcRel}" !== "{$dstCont}/{$dstRel}" ) {
 446                         $reqs[] = array(
 447                                 'method' => 'DELETE',
 448                                 'url' => array( $srcCont, $srcRel ),
 449                                 'headers' => array()
 450                         );
 451                 }
 452
 453                 $that = $this;
 454                 $method = __METHOD__;
 455                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 456                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 457                         if ( $request['method'] === 'PUT' && $rcode === 201 ) {
 458                                 // good
 459                         } elseif ( $request['method'] === 'DELETE' && $rcode === 204 ) {
 460                                 // good
 461                         } elseif ( $rcode === 404 ) {
 462                                 $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 463                         } else {
 464                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 465                         }
 466                 };
 467
 468                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 469                 if ( !empty( $params['async'] ) ) { // deferred
 470                         $status->value = $opHandle;
 471                 } else { // actually move the object in Swift
 472                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 473                 }
 474
 475                 return $status;
 476         }
 477
 478         protected function doDeleteInternal( array $params ) {
 479                 $status = Status::newGood();
 480
 481                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 482                 if ( $srcRel === null ) {
 483                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 484
 485                         return $status;
 486                 }
 487
 488                 $reqs = array( array(
 489                         'method' => 'DELETE',
 490                         'url' => array( $srcCont, $srcRel ),
 491                         'headers' => array()
 492                 ) );
 493
 494                 $that = $this;
 495                 $method = __METHOD__;
 496                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 497                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 498                         if ( $rcode === 204 ) {
 499                                 // good
 500                         } elseif ( $rcode === 404 ) {
 501                                 if ( empty( $params['ignoreMissingSource'] ) ) {
 502                                         $status->fatal( 'backend-fail-delete', $params['src'] );
 503                                 }
 504                         } else {
 505                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 506                         }
 507                 };
 508
 509                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 510                 if ( !empty( $params['async'] ) ) { // deferred
 511                         $status->value = $opHandle;
 512                 } else { // actually delete the object in Swift
 513                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 514                 }
 515
 516                 return $status;
 517         }
 518
 519         protected function doDescribeInternal( array $params ) {
 520                 $status = Status::newGood();
 521
 522                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
 523                 if ( $srcRel === null ) {
 524                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 525
 526                         return $status;
 527                 }
 528
 529                 // Fetch the old object headers/metadata...this should be in stat cache by now
 530                 $stat = $this->getFileStat( array( 'src' => $params['src'], 'latest' => 1 ) );
 531                 if ( $stat && !isset( $stat['xattr'] ) ) { // older cache entry
 532                         $stat = $this->doGetFileStat( array( 'src' => $params['src'], 'latest' => 1 ) );
 533                 }
 534                 if ( !$stat ) {
 535                         $status->fatal( 'backend-fail-describe', $params['src'] );
 536
 537                         return $status;
 538                 }
 539
 540                 // POST clears prior headers, so we need to merge the changes in to the old ones
 541                 $metaHdrs = array();
 542                 foreach ( $stat['xattr']['metadata'] as $name => $value ) {
 543                         $metaHdrs["x-object-meta-$name"] = $value;
 544                 }
 545                 $customHdrs = $this->sanitizeHdrs( $params ) + $stat['xattr']['headers'];
 546
 547                 $reqs = array( array(
 548                         'method' => 'POST',
 549                         'url' => array( $srcCont, $srcRel ),
 550                         'headers' => $metaHdrs + $customHdrs
 551                 ) );
 552
 553                 $that = $this;
 554                 $method = __METHOD__;
 555                 $handler = function ( array $request, Status $status ) use ( $that, $method, $params ) {
 556                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $request['response'];
 557                         if ( $rcode === 202 ) {
 558                                 // good
 559                         } elseif ( $rcode === 404 ) {
 560                                 $status->fatal( 'backend-fail-describe', $params['src'] );
 561                         } else {
 562                                 $that->onError( $status, $method, $params, $rerr, $rcode, $rdesc );
 563                         }
 564                 };
 565
 566                 $opHandle = new SwiftFileOpHandle( $this, $handler, $reqs );
 567                 if ( !empty( $params['async'] ) ) { // deferred
 568                         $status->value = $opHandle;
 569                 } else { // actually change the object in Swift
 570                         $status->merge( current( $this->doExecuteOpHandlesInternal( array( $opHandle ) ) ) );
 571                 }
 572
 573                 return $status;
 574         }
 575
 576         protected function doPrepareInternal( $fullCont, $dir, array $params ) {
 577                 $status = Status::newGood();
 578
 579                 // (a) Check if container already exists
 580                 $stat = $this->getContainerStat( $fullCont );
 581                 if ( is_array( $stat ) ) {
 582                         return $status; // already there
 583                 } elseif ( $stat === null ) {
 584                         $status->fatal( 'backend-fail-internal', $this->name );
 585                         wfDebugLog( 'SwiftBackend', __METHOD__ . ': cannot get container stat' );
 586
 587                         return $status;
 588                 }
 589
 590                 // (b) Create container as needed with proper ACLs
 591                 if ( $stat === false ) {
 592                         $params['op'] = 'prepare';
 593                         $status->merge( $this->createContainer( $fullCont, $params ) );
 594                 }
 595
 596                 return $status;
 597         }
 598
 599         protected function doSecureInternal( $fullCont, $dir, array $params ) {
 600                 $status = Status::newGood();
 601                 if ( empty( $params['noAccess'] ) ) {
 602                         return $status; // nothing to do
 603                 }
 604
 605                 $stat = $this->getContainerStat( $fullCont );
 606                 if ( is_array( $stat ) ) {
 607                         // Make container private to end-users...
 608                         $status->merge( $this->setContainerAccess(
 609                                 $fullCont,
 610                                 array( $this->swiftUser ), // read
 611                                 array( $this->swiftUser ) // write
 612                         ) );
 613                 } elseif ( $stat === false ) {
 614                         $status->fatal( 'backend-fail-usable', $params['dir'] );
 615                 } else {
 616                         $status->fatal( 'backend-fail-internal', $this->name );
 617                         wfDebugLog( 'SwiftBackend', __METHOD__ . ': cannot get container stat' );
 618                 }
 619
 620                 return $status;
 621         }
 622
 623         protected function doPublishInternal( $fullCont, $dir, array $params ) {
 624                 $status = Status::newGood();
 625
 626                 $stat = $this->getContainerStat( $fullCont );
 627                 if ( is_array( $stat ) ) {
 628                         // Make container public to end-users...
 629                         $status->merge( $this->setContainerAccess(
 630                                 $fullCont,
 631                                 array( $this->swiftUser, '.r:*' ), // read
 632                                 array( $this->swiftUser ) // write
 633                         ) );
 634                 } elseif ( $stat === false ) {
 635                         $status->fatal( 'backend-fail-usable', $params['dir'] );
 636                 } else {
 637                         $status->fatal( 'backend-fail-internal', $this->name );
 638                         wfDebugLog( 'SwiftBackend', __METHOD__ . ': cannot get container stat' );
 639                 }
 640
 641                 return $status;
 642         }
 643
 644         protected function doCleanInternal( $fullCont, $dir, array $params ) {
 645                 $status = Status::newGood();
 646
 647                 // Only containers themselves can be removed, all else is virtual
 648                 if ( $dir != '' ) {
 649                         return $status; // nothing to do
 650                 }
 651
 652                 // (a) Check the container
 653                 $stat = $this->getContainerStat( $fullCont, true );
 654                 if ( $stat === false ) {
 655                         return $status; // ok, nothing to do
 656                 } elseif ( !is_array( $stat ) ) {
 657                         $status->fatal( 'backend-fail-internal', $this->name );
 658                         wfDebugLog( 'SwiftBackend', __METHOD__ . ': cannot get container stat' );
 659
 660                         return $status;
 661                 }
 662
 663                 // (b) Delete the container if empty
 664                 if ( $stat['count'] == 0 ) {
 665                         $params['op'] = 'clean';
 666                         $status->merge( $this->deleteContainer( $fullCont, $params ) );
 667                 }
 668
 669                 return $status;
 670         }
 671
 672         protected function doGetFileStat( array $params ) {
 673                 $params = array( 'srcs' => array( $params['src'] ), 'concurrency' => 1 ) + $params;
 674                 unset( $params['src'] );
 675                 $stats = $this->doGetFileStatMulti( $params );
 676
 677                 return reset( $stats );
 678         }
 679
 680         /**
 681          * Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT"/"2013-05-11T07:37:27.678360Z".
 682          * Dates might also come in like "2013-05-11T07:37:27.678360" from Swift listings,
 683          * missing the timezone suffix (though Ceph RGW does not appear to have this bug).
 684          *
 685          * @param string $ts
 686          * @param int $format Output format (TS_* constant)
 687          * @return string
 688          * @throws FileBackendError
 689          */
 690         protected function convertSwiftDate( $ts, $format = TS_MW ) {
 691                 try {
 692                         $timestamp = new MWTimestamp( $ts );
 693
 694                         return $timestamp->getTimestamp( $format );
 695                 } catch ( Exception $e ) {
 696                         throw new FileBackendError( $e->getMessage() );
 697                 }
 698         }
 699
 700         /**
 701          * Fill in any missing object metadata and save it to Swift
 702          *
 703          * @param array $objHdrs Object response headers
 704          * @param string $path Storage path to object
 705          * @return array New headers
 706          */
 707         protected function addMissingMetadata( array $objHdrs, $path ) {
 708                 if ( isset( $objHdrs['x-object-meta-sha1base36'] ) ) {
 709                         return $objHdrs; // nothing to do
 710                 }
 711
 712                 /** @noinspection PhpUnusedLocalVariableInspection */
 713                 $ps = Profiler::instance()->scopedProfileIn( __METHOD__ . "-{$this->name}" );
 714                 wfDebugLog( 'SwiftBackend', __METHOD__ . ": $path was not stored with SHA-1 metadata." );
 715
 716                 $objHdrs['x-object-meta-sha1base36'] = false;
 717
 718                 $auth = $this->getAuthentication();
 719                 if ( !$auth ) {
 720                         return $objHdrs; // failed
 721                 }
 722
 723                 // Find prior custom HTTP headers
 724                 $postHeaders = $this->getCustomHeaders( $objHdrs );
 725                 // Find prior metadata headers
 726                 $postHeaders += $this->getMetadataHeaders( $objHdrs );
 727
 728                 $status = Status::newGood();
 729                 /** @noinspection PhpUnusedLocalVariableInspection */
 730                 $scopeLockS = $this->getScopedFileLocks( array( $path ), LockManager::LOCK_UW, $status );
 731                 if ( $status->isOK() ) {
 732                         $tmpFile = $this->getLocalCopy( array( 'src' => $path, 'latest' => 1 ) );
 733                         if ( $tmpFile ) {
 734                                 $hash = $tmpFile->getSha1Base36();
 735                                 if ( $hash !== false ) {
 736                                         $objHdrs['x-object-meta-sha1base36'] = $hash;
 737                                         // Merge new SHA1 header into the old ones
 738                                         $postHeaders['x-object-meta-sha1base36'] = $hash;
 739                                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
 740                                         list( $rcode ) = $this->http->run( array(
 741                                                 'method' => 'POST',
 742                                                 'url' => $this->storageUrl( $auth, $srcCont, $srcRel ),
 743                                                 'headers' => $this->authTokenHeaders( $auth ) + $postHeaders
 744                                         ) );
 745                                         if ( $rcode >= 200 && $rcode <= 299 ) {
 746                                                 $this->deleteFileCache( $path );
 747
 748                                                 return $objHdrs; // success
 749                                         }
 750                                 }
 751                         }
 752                 }
 753
 754                 wfDebugLog( 'SwiftBackend', __METHOD__ . ": unable to set SHA-1 metadata for $path" );
 755
 756                 return $objHdrs; // failed
 757         }
 758
 759         protected function doGetFileContentsMulti( array $params ) {
 760                 $contents = array();
 761
 762                 $auth = $this->getAuthentication();
 763
 764                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
 765                 // Blindly create tmp files and stream to them, catching any exception if the file does
 766                 // not exist. Doing stats here is useless and will loop infinitely in addMissingMetadata().
 767                 $reqs = array(); // (path => op)
 768
 769                 foreach ( $params['srcs'] as $path ) { // each path in this concurrent batch
 770                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
 771                         if ( $srcRel === null || !$auth ) {
 772                                 $contents[$path] = false;
 773                                 continue;
 774                         }
 775                         // Create a new temporary memory file...
 776                         $handle = fopen( 'php://temp', 'wb' );
 777                         if ( $handle ) {
 778                                 $reqs[$path] = array(
 779                                         'method'  => 'GET',
 780                                         'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
 781                                         'headers' => $this->authTokenHeaders( $auth )
 782                                                 + $this->headersFromParams( $params ),
 783                                         'stream'  => $handle,
 784                                 );
 785                         }
 786                         $contents[$path] = false;
 787                 }
 788
 789                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
 790                 $reqs = $this->http->runMulti( $reqs, $opts );
 791                 foreach ( $reqs as $path => $op ) {
 792                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $op['response'];
 793                         if ( $rcode >= 200 && $rcode <= 299 ) {
 794                                 rewind( $op['stream'] ); // start from the beginning
 795                                 $contents[$path] = stream_get_contents( $op['stream'] );
 796                         } elseif ( $rcode === 404 ) {
 797                                 $contents[$path] = false;
 798                         } else {
 799                                 $this->onError( null, __METHOD__,
 800                                         array( 'src' => $path ) + $ep, $rerr, $rcode, $rdesc );
 801                         }
 802                         fclose( $op['stream'] ); // close open handle
 803                 }
 804
 805                 return $contents;
 806         }
 807
 808         protected function doDirectoryExists( $fullCont, $dir, array $params ) {
 809                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 810                 $status = $this->objectListing( $fullCont, 'names', 1, null, $prefix );
 811                 if ( $status->isOk() ) {
 812                         return ( count( $status->value ) ) > 0;
 813                 }
 814
 815                 return null; // error
 816         }
 817
 818         /**
 819          * @see FileBackendStore::getDirectoryListInternal()
 820          * @param string $fullCont
 821          * @param string $dir
 822          * @param array $params
 823          * @return SwiftFileBackendDirList
 824          */
 825         public function getDirectoryListInternal( $fullCont, $dir, array $params ) {
 826                 return new SwiftFileBackendDirList( $this, $fullCont, $dir, $params );
 827         }
 828
 829         /**
 830          * @see FileBackendStore::getFileListInternal()
 831          * @param string $fullCont
 832          * @param string $dir
 833          * @param array $params
 834          * @return SwiftFileBackendFileList
 835          */
 836         public function getFileListInternal( $fullCont, $dir, array $params ) {
 837                 return new SwiftFileBackendFileList( $this, $fullCont, $dir, $params );
 838         }
 839
 840         /**
 841          * Do not call this function outside of SwiftFileBackendFileList
 842          *
 843          * @param string $fullCont Resolved container name
 844          * @param string $dir Resolved storage directory with no trailing slash
 845          * @param string|null $after Resolved container relative path to list items after
 846          * @param int $limit Max number of items to list
 847          * @param array $params Parameters for getDirectoryList()
 848          * @return array List of container relative resolved paths of directories directly under $dir
 849          * @throws FileBackendError
 850          */
 851         public function getDirListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 852                 $dirs = array();
 853                 if ( $after === INF ) {
 854                         return $dirs; // nothing more
 855                 }
 856
 857                 $ps = Profiler::instance()->scopedProfileIn( __METHOD__ . "-{$this->name}" );
 858
 859                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 860                 // Non-recursive: only list dirs right under $dir
 861                 if ( !empty( $params['topOnly'] ) ) {
 862                         $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix, '/' );
 863                         if ( !$status->isOk() ) {
 864                                 throw new FileBackendError( "Iterator page I/O error: {$status->getMessage()}" );
 865                         }
 866                         $objects = $status->value;
 867                         foreach ( $objects as $object ) { // files and directories
 868                                 if ( substr( $object, -1 ) === '/' ) {
 869                                         $dirs[] = $object; // directories end in '/'
 870                                 }
 871                         }
 872                 } else {
 873                         // Recursive: list all dirs under $dir and its subdirs
 874                         $getParentDir = function ( $path ) {
 875                                 return ( strpos( $path, '/' ) !== false ) ? dirname( $path ) : false;
 876                         };
 877
 878                         // Get directory from last item of prior page
 879                         $lastDir = $getParentDir( $after ); // must be first page
 880                         $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix );
 881
 882                         if ( !$status->isOk() ) {
 883                                 throw new FileBackendError( "Iterator page I/O error: {$status->getMessage()}" );
 884                         }
 885
 886                         $objects = $status->value;
 887
 888                         foreach ( $objects as $object ) { // files
 889                                 $objectDir = $getParentDir( $object ); // directory of object
 890
 891                                 if ( $objectDir !== false && $objectDir !== $dir ) {
 892                                         // Swift stores paths in UTF-8, using binary sorting.
 893                                         // See function "create_container_table" in common/db.py.
 894                                         // If a directory is not "greater" than the last one,
 895                                         // then it was already listed by the calling iterator.
 896                                         if ( strcmp( $objectDir, $lastDir ) > 0 ) {
 897                                                 $pDir = $objectDir;
 898                                                 do { // add dir and all its parent dirs
 899                                                         $dirs[] = "{$pDir}/";
 900                                                         $pDir = $getParentDir( $pDir );
 901                                                 } while ( $pDir !== false // sanity
 902                                                         && strcmp( $pDir, $lastDir ) > 0 // not done already
 903                                                         && strlen( $pDir ) > strlen( $dir ) // within $dir
 904                                                 );
 905                                         }
 906                                         $lastDir = $objectDir;
 907                                 }
 908                         }
 909                 }
 910                 // Page on the unfiltered directory listing (what is returned may be filtered)
 911                 if ( count( $objects ) < $limit ) {
 912                         $after = INF; // avoid a second RTT
 913                 } else {
 914                         $after = end( $objects ); // update last item
 915                 }
 916
 917                 return $dirs;
 918         }
 919
 920         /**
 921          * Do not call this function outside of SwiftFileBackendFileList
 922          *
 923          * @param string $fullCont Resolved container name
 924          * @param string $dir Resolved storage directory with no trailing slash
 925          * @param string|null $after Resolved container relative path of file to list items after
 926          * @param int $limit Max number of items to list
 927          * @param array $params Parameters for getDirectoryList()
 928          * @return array List of resolved container relative paths of files under $dir
 929          * @throws FileBackendError
 930          */
 931         public function getFileListPageInternal( $fullCont, $dir, &$after, $limit, array $params ) {
 932                 $files = array(); // list of (path, stat array or null) entries
 933                 if ( $after === INF ) {
 934                         return $files; // nothing more
 935                 }
 936
 937                 $ps = Profiler::instance()->scopedProfileIn( __METHOD__ . "-{$this->name}" );
 938
 939                 $prefix = ( $dir == '' ) ? null : "{$dir}/";
 940                 // $objects will contain a list of unfiltered names or CF_Object items
 941                 // Non-recursive: only list files right under $dir
 942                 if ( !empty( $params['topOnly'] ) ) {
 943                         if ( !empty( $params['adviseStat'] ) ) {
 944                                 $status = $this->objectListing( $fullCont, 'info', $limit, $after, $prefix, '/' );
 945                         } else {
 946                                 $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix, '/' );
 947                         }
 948                 } else {
 949                         // Recursive: list all files under $dir and its subdirs
 950                         if ( !empty( $params['adviseStat'] ) ) {
 951                                 $status = $this->objectListing( $fullCont, 'info', $limit, $after, $prefix );
 952                         } else {
 953                                 $status = $this->objectListing( $fullCont, 'names', $limit, $after, $prefix );
 954                         }
 955                 }
 956
 957                 // Reformat this list into a list of (name, stat array or null) entries
 958                 if ( !$status->isOk() ) {
 959                         throw new FileBackendError( "Iterator page I/O error: {$status->getMessage()}" );
 960                 }
 961
 962                 $objects = $status->value;
 963                 $files = $this->buildFileObjectListing( $params, $dir, $objects );
 964
 965                 // Page on the unfiltered object listing (what is returned may be filtered)
 966                 if ( count( $objects ) < $limit ) {
 967                         $after = INF; // avoid a second RTT
 968                 } else {
 969                         $after = end( $objects ); // update last item
 970                         $after = is_object( $after ) ? $after->name : $after;
 971                 }
 972
 973                 return $files;
 974         }
 975
 976         /**
 977          * Build a list of file objects, filtering out any directories
 978          * and extracting any stat info if provided in $objects (for CF_Objects)
 979          *
 980          * @param array $params Parameters for getDirectoryList()
 981          * @param string $dir Resolved container directory path
 982          * @param array $objects List of CF_Object items or object names
 983          * @return array List of (names,stat array or null) entries
 984          */
 985         private function buildFileObjectListing( array $params, $dir, array $objects ) {
 986                 $names = array();
 987                 foreach ( $objects as $object ) {
 988                         if ( is_object( $object ) ) {
 989                                 if ( isset( $object->subdir ) || !isset( $object->name ) ) {
 990                                         continue; // virtual directory entry; ignore
 991                                 }
 992                                 $stat = array(
 993                                         // Convert various random Swift dates to TS_MW
 994                                         'mtime'  => $this->convertSwiftDate( $object->last_modified, TS_MW ),
 995                                         'size'   => (int)$object->bytes,
 996                                         'sha1'   => null,
 997                                         // Note: manifiest ETags are not an MD5 of the file
 998                                         'md5'    => ctype_xdigit( $object->hash ) ? $object->hash : null,
 999                                         'latest' => false // eventually consistent
1000                                 );
1001                                 $names[] = array( $object->name, $stat );
1002                         } elseif ( substr( $object, -1 ) !== '/' ) {
1003                                 // Omit directories, which end in '/' in listings
1004                                 $names[] = array( $object, null );
1005                         }
1006                 }
1007
1008                 return $names;
1009         }
1010
1011         /**
1012          * Do not call this function outside of SwiftFileBackendFileList
1013          *
1014          * @param string $path Storage path
1015          * @param array $val Stat value
1016          */
1017         public function loadListingStatInternal( $path, array $val ) {
1018                 $this->cheapCache->set( $path, 'stat', $val );
1019         }
1020
1021         protected function doGetFileXAttributes( array $params ) {
1022                 $stat = $this->getFileStat( $params );
1023                 if ( $stat ) {
1024                         if ( !isset( $stat['xattr'] ) ) {
1025                                 // Stat entries filled by file listings don't include metadata/headers
1026                                 $this->clearCache( array( $params['src'] ) );
1027                                 $stat = $this->getFileStat( $params );
1028                         }
1029
1030                         return $stat['xattr'];
1031                 } else {
1032                         return false;
1033                 }
1034         }
1035
1036         protected function doGetFileSha1base36( array $params ) {
1037                 $stat = $this->getFileStat( $params );
1038                 if ( $stat ) {
1039                         if ( !isset( $stat['sha1'] ) ) {
1040                                 // Stat entries filled by file listings don't include SHA1
1041                                 $this->clearCache( array( $params['src'] ) );
1042                                 $stat = $this->getFileStat( $params );
1043                         }
1044
1045                         return $stat['sha1'];
1046                 } else {
1047                         return false;
1048                 }
1049         }
1050
1051         protected function doStreamFile( array $params ) {
1052                 $status = Status::newGood();
1053
1054                 list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
1055                 if ( $srcRel === null ) {
1056                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
1057                 }
1058
1059                 $auth = $this->getAuthentication();
1060                 if ( !$auth || !is_array( $this->getContainerStat( $srcCont ) ) ) {
1061                         $status->fatal( 'backend-fail-stream', $params['src'] );
1062
1063                         return $status;
1064                 }
1065
1066                 $handle = fopen( 'php://output', 'wb' );
1067
1068                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1069                         'method' => 'GET',
1070                         'url' => $this->storageUrl( $auth, $srcCont, $srcRel ),
1071                         'headers' => $this->authTokenHeaders( $auth )
1072                                 + $this->headersFromParams( $params ),
1073                         'stream' => $handle,
1074                 ) );
1075
1076                 if ( $rcode >= 200 && $rcode <= 299 ) {
1077                         // good
1078                 } elseif ( $rcode === 404 ) {
1079                         $status->fatal( 'backend-fail-stream', $params['src'] );
1080                 } else {
1081                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1082                 }
1083
1084                 return $status;
1085         }
1086
1087         protected function doGetLocalCopyMulti( array $params ) {
1088                 $tmpFiles = array();
1089
1090                 $auth = $this->getAuthentication();
1091
1092                 $ep = array_diff_key( $params, array( 'srcs' => 1 ) ); // for error logging
1093                 // Blindly create tmp files and stream to them, catching any exception if the file does
1094                 // not exist. Doing a stat here is useless causes infinite loops in addMissingMetadata().
1095                 $reqs = array(); // (path => op)
1096
1097                 foreach ( $params['srcs'] as $path ) { // each path in this concurrent batch
1098                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
1099                         if ( $srcRel === null || !$auth ) {
1100                                 $tmpFiles[$path] = null;
1101                                 continue;
1102                         }
1103                         // Get source file extension
1104                         $ext = FileBackend::extensionFromPath( $path );
1105                         // Create a new temporary file...
1106                         $tmpFile = TempFSFile::factory( 'localcopy_', $ext );
1107                         if ( $tmpFile ) {
1108                                 $handle = fopen( $tmpFile->getPath(), 'wb' );
1109                                 if ( $handle ) {
1110                                         $reqs[$path] = array(
1111                                                 'method'  => 'GET',
1112                                                 'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
1113                                                 'headers' => $this->authTokenHeaders( $auth )
1114                                                         + $this->headersFromParams( $params ),
1115                                                 'stream'  => $handle,
1116                                         );
1117                                 } else {
1118                                         $tmpFile = null;
1119                                 }
1120                         }
1121                         $tmpFiles[$path] = $tmpFile;
1122                 }
1123
1124                 $isLatest = ( $this->isRGW || !empty( $params['latest'] ) );
1125                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
1126                 $reqs = $this->http->runMulti( $reqs, $opts );
1127                 foreach ( $reqs as $path => $op ) {
1128                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $op['response'];
1129                         fclose( $op['stream'] ); // close open handle
1130                         if ( $rcode >= 200 && $rcode <= 299 ) {
1131                                 $size = $tmpFiles[$path] ? $tmpFiles[$path]->getSize() : 0;
1132                                 // Double check that the disk is not full/broken
1133                                 if ( $size != $rhdrs['content-length'] ) {
1134                                         $tmpFiles[$path] = null;
1135                                         $rerr = "Got {$size}/{$rhdrs['content-length']} bytes";
1136                                         $this->onError( null, __METHOD__,
1137                                                 array( 'src' => $path ) + $ep, $rerr, $rcode, $rdesc );
1138                                 }
1139                                 // Set the file stat process cache in passing
1140                                 $stat = $this->getStatFromHeaders( $rhdrs );
1141                                 $stat['latest'] = $isLatest;
1142                                 $this->cheapCache->set( $path, 'stat', $stat );
1143                         } elseif ( $rcode === 404 ) {
1144                                 $tmpFiles[$path] = false;
1145                         } else {
1146                                 $tmpFiles[$path] = null;
1147                                 $this->onError( null, __METHOD__,
1148                                         array( 'src' => $path ) + $ep, $rerr, $rcode, $rdesc );
1149                         }
1150                 }
1151
1152                 return $tmpFiles;
1153         }
1154
1155         public function getFileHttpUrl( array $params ) {
1156                 if ( $this->swiftTempUrlKey != '' ||
1157                         ( $this->rgwS3AccessKey != '' && $this->rgwS3SecretKey != '' )
1158                 ) {
1159                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $params['src'] );
1160                         if ( $srcRel === null ) {
1161                                 return null; // invalid path
1162                         }
1163
1164                         $auth = $this->getAuthentication();
1165                         if ( !$auth ) {
1166                                 return null;
1167                         }
1168
1169                         $ttl = isset( $params['ttl'] ) ? $params['ttl'] : 86400;
1170                         $expires = time() + $ttl;
1171
1172                         if ( $this->swiftTempUrlKey != '' ) {
1173                                 $url = $this->storageUrl( $auth, $srcCont, $srcRel );
1174                                 // Swift wants the signature based on the unencoded object name
1175                                 $contPath = parse_url( $this->storageUrl( $auth, $srcCont ), PHP_URL_PATH );
1176                                 $signature = hash_hmac( 'sha1',
1177                                         "GET\n{$expires}\n{$contPath}/{$srcRel}",
1178                                         $this->swiftTempUrlKey
1179                                 );
1180
1181                                 return "{$url}?temp_url_sig={$signature}&temp_url_expires={$expires}";
1182                         } else { // give S3 API URL for rgw
1183                                 // Path for signature starts with the bucket
1184                                 $spath = '/' . rawurlencode( $srcCont ) . '/' .
1185                                         str_replace( '%2F', '/', rawurlencode( $srcRel ) );
1186                                 // Calculate the hash
1187                                 $signature = base64_encode( hash_hmac(
1188                                         'sha1',
1189                                         "GET\n\n\n{$expires}\n{$spath}",
1190                                         $this->rgwS3SecretKey,
1191                                         true // raw
1192                                 ) );
1193                                 // See http://s3.amazonaws.com/doc/s3-developer-guide/RESTAuthentication.html.
1194                                 // Note: adding a newline for empty CanonicalizedAmzHeaders does not work.
1195                                 return wfAppendQuery(
1196                                         str_replace( '/swift/v1', '', // S3 API is the rgw default
1197                                                 $this->storageUrl( $auth ) . $spath ),
1198                                         array(
1199                                                 'Signature' => $signature,
1200                                                 'Expires' => $expires,
1201                                                 'AWSAccessKeyId' => $this->rgwS3AccessKey )
1202                                 );
1203                         }
1204                 }
1205
1206                 return null;
1207         }
1208
1209         protected function directoriesAreVirtual() {
1210                 return true;
1211         }
1212
1213         /**
1214          * Get headers to send to Swift when reading a file based
1215          * on a FileBackend params array, e.g. that of getLocalCopy().
1216          * $params is currently only checked for a 'latest' flag.
1217          *
1218          * @param array $params
1219          * @return array
1220          */
1221         protected function headersFromParams( array $params ) {
1222                 $hdrs = array();
1223                 if ( !empty( $params['latest'] ) ) {
1224                         $hdrs['x-newest'] = 'true';
1225                 }
1226
1227                 return $hdrs;
1228         }
1229
1230         /**
1231          * @param FileBackendStoreOpHandle[] $fileOpHandles
1232          *
1233          * @return Status[]
1234          */
1235         protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
1236                 $statuses = array();
1237
1238                 $auth = $this->getAuthentication();
1239                 if ( !$auth ) {
1240                         foreach ( $fileOpHandles as $index => $fileOpHandle ) {
1241                                 $statuses[$index] = Status::newFatal( 'backend-fail-connect', $this->name );
1242                         }
1243
1244                         return $statuses;
1245                 }
1246
1247                 // Split the HTTP requests into stages that can be done concurrently
1248                 $httpReqsByStage = array(); // map of (stage => index => HTTP request)
1249                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
1250                         $reqs = $fileOpHandle->httpOp;
1251                         // Convert the 'url' parameter to an actual URL using $auth
1252                         foreach ( $reqs as $stage => &$req ) {
1253                                 list( $container, $relPath ) = $req['url'];
1254                                 $req['url'] = $this->storageUrl( $auth, $container, $relPath );
1255                                 $req['headers'] = isset( $req['headers'] ) ? $req['headers'] : array();
1256                                 $req['headers'] = $this->authTokenHeaders( $auth ) + $req['headers'];
1257                                 $httpReqsByStage[$stage][$index] = $req;
1258                         }
1259                         $statuses[$index] = Status::newGood();
1260                 }
1261
1262                 // Run all requests for the first stage, then the next, and so on
1263                 $reqCount = count( $httpReqsByStage );
1264                 for ( $stage = 0; $stage < $reqCount; ++$stage ) {
1265                         $httpReqs = $this->http->runMulti( $httpReqsByStage[$stage] );
1266                         foreach ( $httpReqs as $index => $httpReq ) {
1267                                 // Run the callback for each request of this operation
1268                                 $callback = $fileOpHandles[$index]->callback;
1269                                 call_user_func_array( $callback, array( $httpReq, $statuses[$index] ) );
1270                                 // On failure, abort all remaining requests for this operation
1271                                 // (e.g. abort the DELETE request if the COPY request fails for a move)
1272                                 if ( !$statuses[$index]->isOK() ) {
1273                                         $stages = count( $fileOpHandles[$index]->httpOp );
1274                                         for ( $s = ( $stage + 1 ); $s < $stages; ++$s ) {
1275                                                 unset( $httpReqsByStage[$s][$index] );
1276                                         }
1277                                 }
1278                         }
1279                 }
1280
1281                 return $statuses;
1282         }
1283
1284         /**
1285          * Set read/write permissions for a Swift container.
1286          *
1287          * @see http://swift.openstack.org/misc.html#acls
1288          *
1289          * In general, we don't allow listings to end-users. It's not useful, isn't well-defined
1290          * (lists are truncated to 10000 item with no way to page), and is just a performance risk.
1291          *
1292          * @param string $container Resolved Swift container
1293          * @param array $readGrps List of the possible criteria for a request to have
1294          * access to read a container. Each item is one of the following formats:
1295          *   - account:user        : Grants access if the request is by the given user
1296          *   - ".r:<regex>"        : Grants access if the request is from a referrer host that
1297          *                           matches the expression and the request is not for a listing.
1298          *                           Setting this to '*' effectively makes a container public.
1299          *   -".rlistings:<regex>" : Grants access if the request is from a referrer host that
1300          *                           matches the expression and the request is for a listing.
1301          * @param array $writeGrps A list of the possible criteria for a request to have
1302          * access to write to a container. Each item is of the following format:
1303          *   - account:user       : Grants access if the request is by the given user
1304          * @return Status
1305          */
1306         protected function setContainerAccess( $container, array $readGrps, array $writeGrps ) {
1307                 $status = Status::newGood();
1308                 $auth = $this->getAuthentication();
1309
1310                 if ( !$auth ) {
1311                         $status->fatal( 'backend-fail-connect', $this->name );
1312
1313                         return $status;
1314                 }
1315
1316                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1317                         'method' => 'POST',
1318                         'url' => $this->storageUrl( $auth, $container ),
1319                         'headers' => $this->authTokenHeaders( $auth ) + array(
1320                                 'x-container-read' => implode( ',', $readGrps ),
1321                                 'x-container-write' => implode( ',', $writeGrps )
1322                         )
1323                 ) );
1324
1325                 if ( $rcode != 204 && $rcode !== 202 ) {
1326                         $status->fatal( 'backend-fail-internal', $this->name );
1327                         wfDebugLog( 'SwiftBackend', __METHOD__ . ': unexpected rcode value (' . $rcode . ')' );
1328                 }
1329
1330                 return $status;
1331         }
1332
1333         /**
1334          * Get a Swift container stat array, possibly from process cache.
1335          * Use $reCache if the file count or byte count is needed.
1336          *
1337          * @param string $container Container name
1338          * @param bool $bypassCache Bypass all caches and load from Swift
1339          * @return array|bool|null False on 404, null on failure
1340          */
1341         protected function getContainerStat( $container, $bypassCache = false ) {
1342                 $ps = Profiler::instance()->scopedProfileIn( __METHOD__ . "-{$this->name}" );
1343
1344                 if ( $bypassCache ) { // purge cache
1345                         $this->containerStatCache->clear( $container );
1346                 } elseif ( !$this->containerStatCache->has( $container, 'stat' ) ) {
1347                         $this->primeContainerCache( array( $container ) ); // check persistent cache
1348                 }
1349                 if ( !$this->containerStatCache->has( $container, 'stat' ) ) {
1350                         $auth = $this->getAuthentication();
1351                         if ( !$auth ) {
1352                                 return null;
1353                         }
1354
1355                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1356                                 'method' => 'HEAD',
1357                                 'url' => $this->storageUrl( $auth, $container ),
1358                                 'headers' => $this->authTokenHeaders( $auth )
1359                         ) );
1360
1361                         if ( $rcode === 204 ) {
1362                                 $stat = array(
1363                                         'count' => $rhdrs['x-container-object-count'],
1364                                         'bytes' => $rhdrs['x-container-bytes-used']
1365                                 );
1366                                 if ( $bypassCache ) {
1367                                         return $stat;
1368                                 } else {
1369                                         $this->containerStatCache->set( $container, 'stat', $stat ); // cache it
1370                                         $this->setContainerCache( $container, $stat ); // update persistent cache
1371                                 }
1372                         } elseif ( $rcode === 404 ) {
1373                                 return false;
1374                         } else {
1375                                 $this->onError( null, __METHOD__,
1376                                         array( 'cont' => $container ), $rerr, $rcode, $rdesc );
1377
1378                                 return null;
1379                         }
1380                 }
1381
1382                 return $this->containerStatCache->get( $container, 'stat' );
1383         }
1384
1385         /**
1386          * Create a Swift container
1387          *
1388          * @param string $container Container name
1389          * @param array $params
1390          * @return Status
1391          */
1392         protected function createContainer( $container, array $params ) {
1393                 $status = Status::newGood();
1394
1395                 $auth = $this->getAuthentication();
1396                 if ( !$auth ) {
1397                         $status->fatal( 'backend-fail-connect', $this->name );
1398
1399                         return $status;
1400                 }
1401
1402                 // @see SwiftFileBackend::setContainerAccess()
1403                 if ( empty( $params['noAccess'] ) ) {
1404                         $readGrps = array( '.r:*', $this->swiftUser ); // public
1405                 } else {
1406                         $readGrps = array( $this->swiftUser ); // private
1407                 }
1408                 $writeGrps = array( $this->swiftUser ); // sanity
1409
1410                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1411                         'method' => 'PUT',
1412                         'url' => $this->storageUrl( $auth, $container ),
1413                         'headers' => $this->authTokenHeaders( $auth ) + array(
1414                                 'x-container-read' => implode( ',', $readGrps ),
1415                                 'x-container-write' => implode( ',', $writeGrps )
1416                         )
1417                 ) );
1418
1419                 if ( $rcode === 201 ) { // new
1420                         // good
1421                 } elseif ( $rcode === 202 ) { // already there
1422                         // this shouldn't really happen, but is OK
1423                 } else {
1424                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1425                 }
1426
1427                 return $status;
1428         }
1429
1430         /**
1431          * Delete a Swift container
1432          *
1433          * @param string $container Container name
1434          * @param array $params
1435          * @return Status
1436          */
1437         protected function deleteContainer( $container, array $params ) {
1438                 $status = Status::newGood();
1439
1440                 $auth = $this->getAuthentication();
1441                 if ( !$auth ) {
1442                         $status->fatal( 'backend-fail-connect', $this->name );
1443
1444                         return $status;
1445                 }
1446
1447                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1448                         'method' => 'DELETE',
1449                         'url' => $this->storageUrl( $auth, $container ),
1450                         'headers' => $this->authTokenHeaders( $auth )
1451                 ) );
1452
1453                 if ( $rcode >= 200 && $rcode <= 299 ) { // deleted
1454                         $this->containerStatCache->clear( $container ); // purge
1455                 } elseif ( $rcode === 404 ) { // not there
1456                         // this shouldn't really happen, but is OK
1457                 } elseif ( $rcode === 409 ) { // not empty
1458                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc ); // race?
1459                 } else {
1460                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1461                 }
1462
1463                 return $status;
1464         }
1465
1466         /**
1467          * Get a list of objects under a container.
1468          * Either just the names or a list of stdClass objects with details can be returned.
1469          *
1470          * @param string $fullCont
1471          * @param string $type ('info' for a list of object detail maps, 'names' for names only)
1472          * @param int $limit
1473          * @param string|null $after
1474          * @param string|null $prefix
1475          * @param string|null $delim
1476          * @return Status With the list as value
1477          */
1478         private function objectListing(
1479                 $fullCont, $type, $limit, $after = null, $prefix = null, $delim = null
1480         ) {
1481                 $status = Status::newGood();
1482
1483                 $auth = $this->getAuthentication();
1484                 if ( !$auth ) {
1485                         $status->fatal( 'backend-fail-connect', $this->name );
1486
1487                         return $status;
1488                 }
1489
1490                 $query = array( 'limit' => $limit );
1491                 if ( $type === 'info' ) {
1492                         $query['format'] = 'json';
1493                 }
1494                 if ( $after !== null ) {
1495                         $query['marker'] = $after;
1496                 }
1497                 if ( $prefix !== null ) {
1498                         $query['prefix'] = $prefix;
1499                 }
1500                 if ( $delim !== null ) {
1501                         $query['delimiter'] = $delim;
1502                 }
1503
1504                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1505                         'method' => 'GET',
1506                         'url' => $this->storageUrl( $auth, $fullCont ),
1507                         'query' => $query,
1508                         'headers' => $this->authTokenHeaders( $auth )
1509                 ) );
1510
1511                 $params = array( 'cont' => $fullCont, 'prefix' => $prefix, 'delim' => $delim );
1512                 if ( $rcode === 200 ) { // good
1513                         if ( $type === 'info' ) {
1514                                 $status->value = FormatJson::decode( trim( $rbody ) );
1515                         } else {
1516                                 $status->value = explode( "\n", trim( $rbody ) );
1517                         }
1518                 } elseif ( $rcode === 204 ) {
1519                         $status->value = array(); // empty container
1520                 } elseif ( $rcode === 404 ) {
1521                         $status->value = array(); // no container
1522                 } else {
1523                         $this->onError( $status, __METHOD__, $params, $rerr, $rcode, $rdesc );
1524                 }
1525
1526                 return $status;
1527         }
1528
1529         protected function doPrimeContainerCache( array $containerInfo ) {
1530                 foreach ( $containerInfo as $container => $info ) {
1531                         $this->containerStatCache->set( $container, 'stat', $info );
1532                 }
1533         }
1534
1535         protected function doGetFileStatMulti( array $params ) {
1536                 $stats = array();
1537
1538                 $auth = $this->getAuthentication();
1539
1540                 $reqs = array();
1541                 foreach ( $params['srcs'] as $path ) {
1542                         list( $srcCont, $srcRel ) = $this->resolveStoragePathReal( $path );
1543                         if ( $srcRel === null ) {
1544                                 $stats[$path] = false;
1545                                 continue; // invalid storage path
1546                         } elseif ( !$auth ) {
1547                                 $stats[$path] = null;
1548                                 continue;
1549                         }
1550
1551                         // (a) Check the container
1552                         $cstat = $this->getContainerStat( $srcCont );
1553                         if ( $cstat === false ) {
1554                                 $stats[$path] = false;
1555                                 continue; // ok, nothing to do
1556                         } elseif ( !is_array( $cstat ) ) {
1557                                 $stats[$path] = null;
1558                                 continue;
1559                         }
1560
1561                         $reqs[$path] = array(
1562                                 'method'  => 'HEAD',
1563                                 'url'     => $this->storageUrl( $auth, $srcCont, $srcRel ),
1564                                 'headers' => $this->authTokenHeaders( $auth ) + $this->headersFromParams( $params )
1565                         );
1566                 }
1567
1568                 $opts = array( 'maxConnsPerHost' => $params['concurrency'] );
1569                 $reqs = $this->http->runMulti( $reqs, $opts );
1570
1571                 foreach ( $params['srcs'] as $path ) {
1572                         if ( array_key_exists( $path, $stats ) ) {
1573                                 continue; // some sort of failure above
1574                         }
1575                         // (b) Check the file
1576                         list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $reqs[$path]['response'];
1577                         if ( $rcode === 200 || $rcode === 204 ) {
1578                                 // Update the object if it is missing some headers
1579                                 $rhdrs = $this->addMissingMetadata( $rhdrs, $path );
1580                                 // Load the stat array from the headers
1581                                 $stat = $this->getStatFromHeaders( $rhdrs );
1582                                 if ( $this->isRGW ) {
1583                                         $stat['latest'] = true; // strong consistency
1584                                 }
1585                         } elseif ( $rcode === 404 ) {
1586                                 $stat = false;
1587                         } else {
1588                                 $stat = null;
1589                                 $this->onError( null, __METHOD__, $params, $rerr, $rcode, $rdesc );
1590                         }
1591                         $stats[$path] = $stat;
1592                 }
1593
1594                 return $stats;
1595         }
1596
1597         /**
1598          * @param array $rhdrs
1599          * @return array
1600          */
1601         protected function getStatFromHeaders( array $rhdrs ) {
1602                 // Fetch all of the custom metadata headers
1603                 $metadata = $this->getMetadata( $rhdrs );
1604                 // Fetch all of the custom raw HTTP headers
1605                 $headers = $this->sanitizeHdrs( array( 'headers' => $rhdrs ) );
1606
1607                 return array(
1608                         // Convert various random Swift dates to TS_MW
1609                         'mtime' => $this->convertSwiftDate( $rhdrs['last-modified'], TS_MW ),
1610                         // Empty objects actually return no content-length header in Ceph
1611                         'size'  => isset( $rhdrs['content-length'] ) ? (int)$rhdrs['content-length'] : 0,
1612                         'sha1'  => isset( $metadata['sha1base36'] ) ? $metadata['sha1base36'] : null,
1613                         // Note: manifiest ETags are not an MD5 of the file
1614                         'md5'   => ctype_xdigit( $rhdrs['etag'] ) ? $rhdrs['etag'] : null,
1615                         'xattr' => array( 'metadata' => $metadata, 'headers' => $headers )
1616                 );
1617         }
1618
1619         /**
1620          * @return array|null Credential map
1621          */
1622         protected function getAuthentication() {
1623                 if ( $this->authErrorTimestamp !== null ) {
1624                         if ( ( time() - $this->authErrorTimestamp ) < 60 ) {
1625                                 return null; // failed last attempt; don't bother
1626                         } else { // actually retry this time
1627                                 $this->authErrorTimestamp = null;
1628                         }
1629                 }
1630                 // Session keys expire after a while, so we renew them periodically
1631                 $reAuth = ( ( time() - $this->authSessionTimestamp ) > $this->authTTL );
1632                 // Authenticate with proxy and get a session key...
1633                 if ( !$this->authCreds || $reAuth ) {
1634                         $this->authSessionTimestamp = 0;
1635                         $cacheKey = $this->getCredsCacheKey( $this->swiftUser );
1636                         $creds = $this->srvCache->get( $cacheKey ); // credentials
1637                         // Try to use the credential cache
1638                         if ( isset( $creds['auth_token'] ) && isset( $creds['storage_url'] ) ) {
1639                                 $this->authCreds = $creds;
1640                                 // Skew the timestamp for worst case to avoid using stale credentials
1641                                 $this->authSessionTimestamp = time() - ceil( $this->authTTL / 2 );
1642                         } else { // cache miss
1643                                 list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->http->run( array(
1644                                         'method' => 'GET',
1645                                         'url' => "{$this->swiftAuthUrl}/v1.0",
1646                                         'headers' => array(
1647                                                 'x-auth-user' => $this->swiftUser,
1648                                                 'x-auth-key' => $this->swiftKey
1649                                         )
1650                                 ) );
1651
1652                                 if ( $rcode >= 200 && $rcode <= 299 ) { // OK
1653                                         $this->authCreds = array(
1654                                                 'auth_token' => $rhdrs['x-auth-token'],
1655                                                 'storage_url' => $rhdrs['x-storage-url']
1656                                         );
1657                                         $this->srvCache->set( $cacheKey, $this->authCreds, ceil( $this->authTTL / 2 ) );
1658                                         $this->authSessionTimestamp = time();
1659                                 } elseif ( $rcode === 401 ) {
1660                                         $this->onError( null, __METHOD__, array(), "Authentication failed.", $rcode );
1661                                         $this->authErrorTimestamp = time();
1662
1663                                         return null;
1664                                 } else {
1665                                         $this->onError( null, __METHOD__, array(), "HTTP return code: $rcode", $rcode );
1666                                         $this->authErrorTimestamp = time();
1667
1668                                         return null;
1669                                 }
1670                         }
1671                         // Ceph RGW does not use <account> in URLs (OpenStack Swift uses "/v1/<account>")
1672                         if ( substr( $this->authCreds['storage_url'], -3 ) === '/v1' ) {
1673                                 $this->isRGW = true; // take advantage of strong consistency in Ceph
1674                         }
1675                 }
1676
1677                 return $this->authCreds;
1678         }
1679
1680         /**
1681          * @param array $creds From getAuthentication()
1682          * @param string $container
1683          * @param string $object
1684          * @return array
1685          */
1686         protected function storageUrl( array $creds, $container = null, $object = null ) {
1687                 $parts = array( $creds['storage_url'] );
1688                 if ( strlen( $container ) ) {
1689                         $parts[] = rawurlencode( $container );
1690                 }
1691                 if ( strlen( $object ) ) {
1692                         $parts[] = str_replace( "%2F", "/", rawurlencode( $object ) );
1693                 }
1694
1695                 return implode( '/', $parts );
1696         }
1697
1698         /**
1699          * @param array $creds From getAuthentication()
1700          * @return array
1701          */
1702         protected function authTokenHeaders( array $creds ) {
1703                 return array( 'x-auth-token' => $creds['auth_token'] );
1704         }
1705
1706         /**
1707          * Get the cache key for a container
1708          *
1709          * @param string $username
1710          * @return string
1711          */
1712         private function getCredsCacheKey( $username ) {
1713                 return 'swiftcredentials:' . md5( $username . ':' . $this->swiftAuthUrl );
1714         }
1715
1716         /**
1717          * Log an unexpected exception for this backend.
1718          * This also sets the Status object to have a fatal error.
1719          *
1720          * @param Status|null $status
1721          * @param string $func
1722          * @param array $params
1723          * @param string $err Error string
1724          * @param int $code HTTP status
1725          * @param string $desc HTTP status description
1726          */
1727         public function onError( $status, $func, array $params, $err = '', $code = 0, $desc = '' ) {
1728                 if ( $status instanceof Status ) {
1729                         $status->fatal( 'backend-fail-internal', $this->name );
1730                 }
1731                 if ( $code == 401 ) { // possibly a stale token
1732                         $this->srvCache->delete( $this->getCredsCacheKey( $this->swiftUser ) );
1733                 }
1734                 wfDebugLog( 'SwiftBackend',
1735                         "HTTP $code ($desc) in '{$func}' (given '" . FormatJson::encode( $params ) . "')" .
1736                         ( $err ? ": $err" : "" )
1737                 );
1738         }
1739 }
1740
1741 /**
1742  * @see FileBackendStoreOpHandle
1743  */
1744 class SwiftFileOpHandle extends FileBackendStoreOpHandle {
1745         /** @var array List of Requests for MultiHttpClient */
1746         public $httpOp;
1747         /** @var Closure */
1748         public $callback;
1749
1750         /**
1751          * @param SwiftFileBackend $backend
1752          * @param Closure $callback Function that takes (HTTP request array, status)
1753          * @param array $httpOp MultiHttpClient op
1754          */
1755         public function __construct( SwiftFileBackend $backend, Closure $callback, array $httpOp ) {
1756                 $this->backend = $backend;
1757                 $this->callback = $callback;
1758                 $this->httpOp = $httpOp;
1759         }
1760 }
1761
1762 /**
1763  * SwiftFileBackend helper class to page through listings.
1764  * Swift also has a listing limit of 10,000 objects for sanity.
1765  * Do not use this class from places outside SwiftFileBackend.
1766  *
1767  * @ingroup FileBackend
1768  */
1769 abstract class SwiftFileBackendList implements Iterator {
1770         /** @var array List of path or (path,stat array) entries */
1771         protected $bufferIter = array();
1772
1773         /** @var string List items *after* this path */
1774         protected $bufferAfter = null;
1775
1776         /** @var int */
1777         protected $pos = 0;
1778
1779         /** @var array */
1780         protected $params = array();
1781
1782         /** @var SwiftFileBackend */
1783         protected $backend;
1784
1785         /** @var string Container name */
1786         protected $container;
1787
1788         /** @var string Storage directory */
1789         protected $dir;
1790
1791         /** @var int */
1792         protected $suffixStart;
1793
1794         const PAGE_SIZE = 9000; // file listing buffer size
1795
1796         /**
1797          * @param SwiftFileBackend $backend
1798          * @param string $fullCont Resolved container name
1799          * @param string $dir Resolved directory relative to container
1800          * @param array $params
1801          */
1802         public function __construct( SwiftFileBackend $backend, $fullCont, $dir, array $params ) {
1803                 $this->backend = $backend;
1804                 $this->container = $fullCont;
1805                 $this->dir = $dir;
1806                 if ( substr( $this->dir, -1 ) === '/' ) {
1807                         $this->dir = substr( $this->dir, 0, -1 ); // remove trailing slash
1808                 }
1809                 if ( $this->dir == '' ) { // whole container
1810                         $this->suffixStart = 0;
1811                 } else { // dir within container
1812                         $this->suffixStart = strlen( $this->dir ) + 1; // size of "path/to/dir/"
1813                 }
1814                 $this->params = $params;
1815         }
1816
1817         /**
1818          * @see Iterator::key()
1819          * @return int
1820          */
1821         public function key() {
1822                 return $this->pos;
1823         }
1824
1825         /**
1826          * @see Iterator::next()
1827          */
1828         public function next() {
1829                 // Advance to the next file in the page
1830                 next( $this->bufferIter );
1831                 ++$this->pos;
1832                 // Check if there are no files left in this page and
1833                 // advance to the next page if this page was not empty.
1834                 if ( !$this->valid() && count( $this->bufferIter ) ) {
1835                         $this->bufferIter = $this->pageFromList(
1836                                 $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1837                         ); // updates $this->bufferAfter
1838                 }
1839         }
1840
1841         /**
1842          * @see Iterator::rewind()
1843          */
1844         public function rewind() {
1845                 $this->pos = 0;
1846                 $this->bufferAfter = null;
1847                 $this->bufferIter = $this->pageFromList(
1848                         $this->container, $this->dir, $this->bufferAfter, self::PAGE_SIZE, $this->params
1849                 ); // updates $this->bufferAfter
1850         }
1851
1852         /**
1853          * @see Iterator::valid()
1854          * @return bool
1855          */
1856         public function valid() {
1857                 if ( $this->bufferIter === null ) {
1858                         return false; // some failure?
1859                 } else {
1860                         return ( current( $this->bufferIter ) !== false ); // no paths can have this value
1861                 }
1862         }
1863
1864         /**
1865          * Get the given list portion (page)
1866          *
1867          * @param string $container Resolved container name
1868          * @param string $dir Resolved path relative to container
1869          * @param string $after
1870          * @param int $limit
1871          * @param array $params
1872          * @return Traversable|array
1873          */
1874         abstract protected function pageFromList( $container, $dir, &$after, $limit, array $params );
1875 }
1876
1877 /**
1878  * Iterator for listing directories
1879  */
1880 class SwiftFileBackendDirList extends SwiftFileBackendList {
1881         /**
1882          * @see Iterator::current()
1883          * @return string|bool String (relative path) or false
1884          */
1885         public function current() {
1886                 return substr( current( $this->bufferIter ), $this->suffixStart, -1 );
1887         }
1888
1889         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1890                 return $this->backend->getDirListPageInternal( $container, $dir, $after, $limit, $params );
1891         }
1892 }
1893
1894 /**
1895  * Iterator for listing regular files
1896  */
1897 class SwiftFileBackendFileList extends SwiftFileBackendList {
1898         /**
1899          * @see Iterator::current()
1900          * @return string|bool String (relative path) or false
1901          */
1902         public function current() {
1903                 list( $path, $stat ) = current( $this->bufferIter );
1904                 $relPath = substr( $path, $this->suffixStart );
1905                 if ( is_array( $stat ) ) {
1906                         $storageDir = rtrim( $this->params['dir'], '/' );
1907                         $this->backend->loadListingStatInternal( "$storageDir/$relPath", $stat );
1908                 }
1909
1910                 return $relPath;
1911         }
1912
1913         protected function pageFromList( $container, $dir, &$after, $limit, array $params ) {
1914                 return $this->backend->getFileListPageInternal( $container, $dir, $after, $limit, $params );
1915         }
1916 }