includes/specials/SpecialUploadStash.php

   1 <?php
   2 /**
   3  * Implements Special:UploadStash.
   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  */
  22
  23 /**
  24  * Web access for files temporarily stored by UploadStash.
  25  *
  26  * For example -- files that were uploaded with the UploadWizard extension are stored temporarily
  27  * before committing them to the db. But we want to see their thumbnails and get other information
  28  * about them.
  29  *
  30  * Since this is based on the user's session, in effect this creates a private temporary file area.
  31  * However, the URLs for the files cannot be shared.
  32  *
  33  * @ingroup SpecialPage
  34  * @ingroup Upload
  35  */
  36 class SpecialUploadStash extends UnlistedSpecialPage {
  37         // UploadStash
  38         private $stash;
  39
  40         /**
  41          * Since we are directly writing the file to STDOUT,
  42          * we should not be reading in really big files and serving them out.
  43          *
  44          * We also don't want people using this as a file drop, even if they
  45          * share credentials.
  46          *
  47          * This service is really for thumbnails and other such previews while
  48          * uploading.
  49          */
  50         const MAX_SERVE_BYTES = 1048576; // 1MB
  51
  52         public function __construct() {
  53                 parent::__construct( 'UploadStash', 'upload' );
  54         }
  55
  56         public function doesWrites() {
  57                 return true;
  58         }
  59
  60         /**
  61          * Execute page -- can output a file directly or show a listing of them.
  62          *
  63          * @param string $subPage Subpage, e.g. in
  64          *   https://example.com/wiki/Special:UploadStash/foo.jpg, the "foo.jpg" part
  65          * @return bool Success
  66          */
  67         public function execute( $subPage ) {
  68                 $this->useTransactionalTimeLimit();
  69
  70                 $this->stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $this->getUser() );
  71                 $this->checkPermissions();
  72
  73                 if ( $subPage === null || $subPage === '' ) {
  74                         return $this->showUploads();
  75                 }
  76
  77                 return $this->showUpload( $subPage );
  78         }
  79
  80         /**
  81          * If file available in stash, cats it out to the client as a simple HTTP response.
  82          * n.b. Most sanity checking done in UploadStashLocalFile, so this is straightforward.
  83          *
  84          * @param string $key The key of a particular requested file
  85          * @throws HttpError
  86          * @return bool
  87          */
  88         public function showUpload( $key ) {
  89                 // prevent callers from doing standard HTML output -- we'll take it from here
  90                 $this->getOutput()->disable();
  91
  92                 try {
  93                         $params = $this->parseKey( $key );
  94                         if ( $params['type'] === 'thumb' ) {
  95                                 return $this->outputThumbFromStash( $params['file'], $params['params'] );
  96                         } else {
  97                                 return $this->outputLocalFile( $params['file'] );
  98                         }
  99                 } catch ( UploadStashFileNotFoundException $e ) {
 100                         $code = 404;
 101                         $message = $e->getMessage();
 102                 } catch ( UploadStashZeroLengthFileException $e ) {
 103                         $code = 500;
 104                         $message = $e->getMessage();
 105                 } catch ( UploadStashBadPathException $e ) {
 106                         $code = 500;
 107                         $message = $e->getMessage();
 108                 } catch ( SpecialUploadStashTooLargeException $e ) {
 109                         $code = 500;
 110                         $message = $e->getMessage();
 111                 } catch ( Exception $e ) {
 112                         $code = 500;
 113                         $message = $e->getMessage();
 114                 }
 115
 116                 throw new HttpError( $code, $message );
 117         }
 118
 119         /**
 120          * Parse the key passed to the SpecialPage. Returns an array containing
 121          * the associated file object, the type ('file' or 'thumb') and if
 122          * application the transform parameters
 123          *
 124          * @param string $key
 125          * @throws UploadStashBadPathException
 126          * @return array
 127          */
 128         private function parseKey( $key ) {
 129                 $type = strtok( $key, '/' );
 130
 131                 if ( $type !== 'file' && $type !== 'thumb' ) {
 132                         throw new UploadStashBadPathException(
 133                                 wfMessage( 'uploadstash-bad-path-unknown-type', $type )
 134                         );
 135                 }
 136                 $fileName = strtok( '/' );
 137                 $thumbPart = strtok( '/' );
 138                 $file = $this->stash->getFile( $fileName );
 139                 if ( $type === 'thumb' ) {
 140                         $srcNamePos = strrpos( $thumbPart, $fileName );
 141                         if ( $srcNamePos === false || $srcNamePos < 1 ) {
 142                                 throw new UploadStashBadPathException(
 143                                         wfMessage( 'uploadstash-bad-path-unrecognized-thumb-name' )
 144                                 );
 145                         }
 146                         $paramString = substr( $thumbPart, 0, $srcNamePos - 1 );
 147
 148                         $handler = $file->getHandler();
 149                         if ( $handler ) {
 150                                 $params = $handler->parseParamString( $paramString );
 151
 152                                 return [ 'file' => $file, 'type' => $type, 'params' => $params ];
 153                         } else {
 154                                 throw new UploadStashBadPathException(
 155                                         wfMessage( 'uploadstash-bad-path-no-handler', $file->getMimeType(), $file->getPath() )
 156                                 );
 157                         }
 158                 }
 159
 160                 return [ 'file' => $file, 'type' => $type ];
 161         }
 162
 163         /**
 164          * Get a thumbnail for file, either generated locally or remotely, and stream it out
 165          *
 166          * @param File $file
 167          * @param array $params
 168          *
 169          * @return bool Success
 170          */
 171         private function outputThumbFromStash( $file, $params ) {
 172                 $flags = 0;
 173                 // this config option, if it exists, points to a "scaler", as you might find in
 174                 // the Wikimedia Foundation cluster. See outputRemoteScaledThumb(). This
 175                 // is part of our horrible NFS-based system, we create a file on a mount
 176                 // point here, but fetch the scaled file from somewhere else that
 177                 // happens to share it over NFS.
 178                 if ( $this->getConfig()->get( 'UploadStashScalerBaseUrl' ) ) {
 179                         $this->outputRemoteScaledThumb( $file, $params, $flags );
 180                 } else {
 181                         $this->outputLocallyScaledThumb( $file, $params, $flags );
 182                 }
 183         }
 184
 185         /**
 186          * Scale a file (probably with a locally installed imagemagick, or similar)
 187          * and output it to STDOUT.
 188          * @param File $file
 189          * @param array $params Scaling parameters ( e.g. [ width => '50' ] );
 190          * @param int $flags Scaling flags ( see File:: constants )
 191          * @throws MWException|UploadStashFileNotFoundException
 192          * @return bool Success
 193          */
 194         private function outputLocallyScaledThumb( $file, $params, $flags ) {
 195                 // n.b. this is stupid, we insist on re-transforming the file every time we are invoked. We rely
 196                 // on HTTP caching to ensure this doesn't happen.
 197
 198                 $flags |= File::RENDER_NOW;
 199
 200                 $thumbnailImage = $file->transform( $params, $flags );
 201                 if ( !$thumbnailImage ) {
 202                         throw new UploadStashFileNotFoundException(
 203                                 wfMessage( 'uploadstash-file-not-found-no-thumb' )
 204                         );
 205                 }
 206
 207                 // we should have just generated it locally
 208                 if ( !$thumbnailImage->getStoragePath() ) {
 209                         throw new UploadStashFileNotFoundException(
 210                                 wfMessage( 'uploadstash-file-not-found-no-local-path' )
 211                         );
 212                 }
 213
 214                 // now we should construct a File, so we can get MIME and other such info in a standard way
 215                 // n.b. MIME type may be different from original (ogx original -> jpeg thumb)
 216                 $thumbFile = new UnregisteredLocalFile( false,
 217                         $this->stash->repo, $thumbnailImage->getStoragePath(), false );
 218                 if ( !$thumbFile ) {
 219                         throw new UploadStashFileNotFoundException(
 220                                 wfMessage( 'uploadstash-file-not-found-no-object' )
 221                         );
 222                 }
 223
 224                 return $this->outputLocalFile( $thumbFile );
 225         }
 226
 227         /**
 228          * Scale a file with a remote "scaler", as exists on the Wikimedia Foundation
 229          * cluster, and output it to STDOUT.
 230          * Note: Unlike the usual thumbnail process, the web client never sees the
 231          * cluster URL; we do the whole HTTP transaction to the scaler ourselves
 232          * and cat the results out.
 233          * Note: We rely on NFS to have propagated the file contents to the scaler.
 234          * However, we do not rely on the thumbnail being created in NFS and then
 235          * propagated back to our filesystem. Instead we take the results of the
 236          * HTTP request instead.
 237          * Note: No caching is being done here, although we are instructing the
 238          * client to cache it forever.
 239          *
 240          * @param File $file
 241          * @param array $params Scaling parameters ( e.g. [ width => '50' ] );
 242          * @param int $flags Scaling flags ( see File:: constants )
 243          * @throws MWException
 244          * @return bool Success
 245          */
 246         private function outputRemoteScaledThumb( $file, $params, $flags ) {
 247                 // This option probably looks something like
 248                 // '//upload.wikimedia.org/wikipedia/test/thumb/temp'. Do not use
 249                 // trailing slash.
 250                 $scalerBaseUrl = $this->getConfig()->get( 'UploadStashScalerBaseUrl' );
 251
 252                 if ( preg_match( '/^\/\//', $scalerBaseUrl ) ) {
 253                         // this is apparently a protocol-relative URL, which makes no sense in this context,
 254                         // since this is used for communication that's internal to the application.
 255                         // default to http.
 256                         $scalerBaseUrl = wfExpandUrl( $scalerBaseUrl, PROTO_CANONICAL );
 257                 }
 258
 259                 // We need to use generateThumbName() instead of thumbName(), because
 260                 // the suffix needs to match the file name for the remote thumbnailer
 261                 // to work
 262                 $scalerThumbName = $file->generateThumbName( $file->getName(), $params );
 263                 $scalerThumbUrl = $scalerBaseUrl . '/' . $file->getUrlRel() .
 264                         '/' . rawurlencode( $scalerThumbName );
 265
 266                 // make a curl call to the scaler to create a thumbnail
 267                 $httpOptions = [
 268                         'method' => 'GET',
 269                         'timeout' => 5 // T90599 attempt to time out cleanly
 270                 ];
 271                 $req = MWHttpRequest::factory( $scalerThumbUrl, $httpOptions, __METHOD__ );
 272                 $status = $req->execute();
 273                 if ( !$status->isOK() ) {
 274                         $errors = $status->getErrorsArray();
 275                         throw new UploadStashFileNotFoundException(
 276                                 wfMessage(
 277                                         'uploadstash-file-not-found-no-remote-thumb',
 278                                         print_r( $errors, 1 ),
 279                                         $scalerThumbUrl
 280                                 )
 281                         );
 282                 }
 283                 $contentType = $req->getResponseHeader( "content-type" );
 284                 if ( !$contentType ) {
 285                         throw new UploadStashFileNotFoundException(
 286                                 wfMessage( 'uploadstash-file-not-found-missing-content-type' )
 287                         );
 288                 }
 289
 290                 return $this->outputContents( $req->getContent(), $contentType );
 291         }
 292
 293         /**
 294          * Output HTTP response for file
 295          * Side effect: writes HTTP response to STDOUT.
 296          *
 297          * @param File $file File object with a local path (e.g. UnregisteredLocalFile,
 298          *   LocalFile. Oddly these don't share an ancestor!)
 299          * @throws SpecialUploadStashTooLargeException
 300          * @return bool
 301          */
 302         private function outputLocalFile( File $file ) {
 303                 if ( $file->getSize() > self::MAX_SERVE_BYTES ) {
 304                         throw new SpecialUploadStashTooLargeException(
 305                                 wfMessage( 'uploadstash-file-too-large', self::MAX_SERVE_BYTES )
 306                         );
 307                 }
 308
 309                 return $file->getRepo()->streamFile( $file->getPath(),
 310                         [ 'Content-Transfer-Encoding: binary',
 311                                 'Expires: Sun, 17-Jan-2038 19:14:07 GMT' ]
 312                 );
 313         }
 314
 315         /**
 316          * Output HTTP response of raw content
 317          * Side effect: writes HTTP response to STDOUT.
 318          * @param string $content
 319          * @param string $contentType MIME type
 320          * @throws SpecialUploadStashTooLargeException
 321          * @return bool
 322          */
 323         private function outputContents( $content, $contentType ) {
 324                 $size = strlen( $content );
 325                 if ( $size > self::MAX_SERVE_BYTES ) {
 326                         throw new SpecialUploadStashTooLargeException(
 327                                 wfMessage( 'uploadstash-file-too-large', self::MAX_SERVE_BYTES )
 328                         );
 329                 }
 330                 // Cancel output buffering and gzipping if set
 331                 wfResetOutputBuffers();
 332                 self::outputFileHeaders( $contentType, $size );
 333                 print $content;
 334
 335                 return true;
 336         }
 337
 338         /**
 339          * Output headers for streaming
 340          * @todo Unsure about encoding as binary; if we received from HTTP perhaps
 341          * we should use that encoding, concatenated with semicolon to `$contentType` as it
 342          * usually is.
 343          * Side effect: preps PHP to write headers to STDOUT.
 344          * @param string $contentType String suitable for content-type header
 345          * @param string $size Length in bytes
 346          */
 347         private static function outputFileHeaders( $contentType, $size ) {
 348                 header( "Content-Type: $contentType", true );
 349                 header( 'Content-Transfer-Encoding: binary', true );
 350                 header( 'Expires: Sun, 17-Jan-2038 19:14:07 GMT', true );
 351                 // T55032 - It shouldn't be a problem here, but let's be safe and not cache
 352                 header( 'Cache-Control: private' );
 353                 header( "Content-Length: $size", true );
 354         }
 355
 356         /**
 357          * Static callback for the HTMLForm in showUploads, to process
 358          * Note the stash has to be recreated since this is being called in a static context.
 359          * This works, because there really is only one stash per logged-in user, despite appearances.
 360          *
 361          * @param array $formData
 362          * @param HTMLForm $form
 363          * @return Status
 364          */
 365         public static function tryClearStashedUploads( $formData, $form ) {
 366                 if ( isset( $formData['Clear'] ) ) {
 367                         $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $form->getUser() );
 368                         wfDebug( 'stash has: ' . print_r( $stash->listFiles(), true ) . "\n" );
 369
 370                         if ( !$stash->clear() ) {
 371                                 return Status::newFatal( 'uploadstash-errclear' );
 372                         }
 373                 }
 374
 375                 return Status::newGood();
 376         }
 377
 378         /**
 379          * Default action when we don't have a subpage -- just show links to the uploads we have,
 380          * Also show a button to clear stashed files
 381          * @return bool
 382          */
 383         private function showUploads() {
 384                 // sets the title, etc.
 385                 $this->setHeaders();
 386                 $this->outputHeader();
 387
 388                 // create the form, which will also be used to execute a callback to process incoming form data
 389                 // this design is extremely dubious, but supposedly HTMLForm is our standard now?
 390
 391                 $context = new DerivativeContext( $this->getContext() );
 392                 $context->setTitle( $this->getPageTitle() ); // Remove subpage
 393                 $form = HTMLForm::factory( 'ooui', [
 394                         'Clear' => [
 395                                 'type' => 'hidden',
 396                                 'default' => true,
 397                                 'name' => 'clear',
 398                         ]
 399                 ], $context, 'clearStashedUploads' );
 400                 $form->setSubmitDestructive();
 401                 $form->setSubmitCallback( [ __CLASS__, 'tryClearStashedUploads' ] );
 402                 $form->setSubmitTextMsg( 'uploadstash-clear' );
 403
 404                 $form->prepareForm();
 405                 $formResult = $form->tryAuthorizedSubmit();
 406
 407                 // show the files + form, if there are any, or just say there are none
 408                 $refreshHtml = Html::element( 'a',
 409                         [ 'href' => $this->getPageTitle()->getLocalURL() ],
 410                         $this->msg( 'uploadstash-refresh' )->text() );
 411                 $files = $this->stash->listFiles();
 412                 if ( $files && count( $files ) ) {
 413                         sort( $files );
 414                         $fileListItemsHtml = '';
 415                         $linkRenderer = $this->getLinkRenderer();
 416                         foreach ( $files as $file ) {
 417                                 $itemHtml = $linkRenderer->makeKnownLink(
 418                                         $this->getPageTitle( "file/$file" ),
 419                                         $file
 420                                 );
 421                                 try {
 422                                         $fileObj = $this->stash->getFile( $file );
 423                                         $thumb = $fileObj->generateThumbName( $file, [ 'width' => 220 ] );
 424                                         $itemHtml .=
 425                                                 $this->msg( 'word-separator' )->escaped() .
 426                                                 $this->msg( 'parentheses' )->rawParams(
 427                                                         $linkRenderer->makeKnownLink(
 428                                                                 $this->getPageTitle( "thumb/$file/$thumb" ),
 429                                                                 $this->msg( 'uploadstash-thumbnail' )->text()
 430                                                         )
 431                                                 )->escaped();
 432                                 } catch ( Exception $e ) {
 433                                 }
 434                                 $fileListItemsHtml .= Html::rawElement( 'li', [], $itemHtml );
 435                         }
 436                         $this->getOutput()->addHTML( Html::rawElement( 'ul', [], $fileListItemsHtml ) );
 437                         $form->displayForm( $formResult );
 438                         $this->getOutput()->addHTML( Html::rawElement( 'p', [], $refreshHtml ) );
 439                 } else {
 440                         $this->getOutput()->addHTML( Html::rawElement( 'p', [],
 441                                 Html::element( 'span', [], $this->msg( 'uploadstash-nofiles' )->text() )
 442                                 . ' '
 443                                 . $refreshHtml
 444                         ) );
 445                 }
 446
 447                 return true;
 448         }
 449 }
 450
 451 /**
 452  * @ingroup SpecialPage
 453  * @ingroup Upload
 454  */
 455 class SpecialUploadStashTooLargeException extends UploadStashException {
 456 }