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                                 $this->msg( '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                                         $this->msg( '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                                         $this->msg( '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         private function outputThumbFromStash( $file, $params ) {
 170                 $flags = 0;
 171                 // this config option, if it exists, points to a "scaler", as you might find in
 172                 // the Wikimedia Foundation cluster. See outputRemoteScaledThumb(). This
 173                 // is part of our horrible NFS-based system, we create a file on a mount
 174                 // point here, but fetch the scaled file from somewhere else that
 175                 // happens to share it over NFS.
 176                 if ( $this->getConfig()->get( 'UploadStashScalerBaseUrl' ) ) {
 177                         $this->outputRemoteScaledThumb( $file, $params, $flags );
 178                 } else {
 179                         $this->outputLocallyScaledThumb( $file, $params, $flags );
 180                 }
 181         }
 182
 183         /**
 184          * Scale a file (probably with a locally installed imagemagick, or similar)
 185          * and output it to STDOUT.
 186          * @param File $file
 187          * @param array $params Scaling parameters ( e.g. [ width => '50' ] );
 188          * @param int $flags Scaling flags ( see File:: constants )
 189          * @throws MWException|UploadStashFileNotFoundException
 190          * @return bool Success
 191          */
 192         private function outputLocallyScaledThumb( $file, $params, $flags ) {
 193                 // n.b. this is stupid, we insist on re-transforming the file every time we are invoked. We rely
 194                 // on HTTP caching to ensure this doesn't happen.
 195
 196                 $flags |= File::RENDER_NOW;
 197
 198                 $thumbnailImage = $file->transform( $params, $flags );
 199                 if ( !$thumbnailImage ) {
 200                         throw new UploadStashFileNotFoundException(
 201                                 $this->msg( 'uploadstash-file-not-found-no-thumb' )
 202                         );
 203                 }
 204
 205                 // we should have just generated it locally
 206                 if ( !$thumbnailImage->getStoragePath() ) {
 207                         throw new UploadStashFileNotFoundException(
 208                                 $this->msg( 'uploadstash-file-not-found-no-local-path' )
 209                         );
 210                 }
 211
 212                 // now we should construct a File, so we can get MIME and other such info in a standard way
 213                 // n.b. MIME type may be different from original (ogx original -> jpeg thumb)
 214                 $thumbFile = new UnregisteredLocalFile( false,
 215                         $this->stash->repo, $thumbnailImage->getStoragePath(), false );
 216                 if ( !$thumbFile ) {
 217                         throw new UploadStashFileNotFoundException(
 218                                 $this->msg( 'uploadstash-file-not-found-no-object' )
 219                         );
 220                 }
 221
 222                 return $this->outputLocalFile( $thumbFile );
 223         }
 224
 225         /**
 226          * Scale a file with a remote "scaler", as exists on the Wikimedia Foundation
 227          * cluster, and output it to STDOUT.
 228          * Note: Unlike the usual thumbnail process, the web client never sees the
 229          * cluster URL; we do the whole HTTP transaction to the scaler ourselves
 230          * and cat the results out.
 231          * Note: We rely on NFS to have propagated the file contents to the scaler.
 232          * However, we do not rely on the thumbnail being created in NFS and then
 233          * propagated back to our filesystem. Instead we take the results of the
 234          * HTTP request instead.
 235          * Note: No caching is being done here, although we are instructing the
 236          * client to cache it forever.
 237          *
 238          * @param File $file
 239          * @param array $params Scaling parameters ( e.g. [ width => '50' ] );
 240          * @param int $flags Scaling flags ( see File:: constants )
 241          * @throws MWException
 242          * @return bool Success
 243          */
 244         private function outputRemoteScaledThumb( $file, $params, $flags ) {
 245                 // This option probably looks something like
 246                 // '//upload.wikimedia.org/wikipedia/test/thumb/temp'. Do not use
 247                 // trailing slash.
 248                 $scalerBaseUrl = $this->getConfig()->get( 'UploadStashScalerBaseUrl' );
 249
 250                 if ( preg_match( '/^\/\//', $scalerBaseUrl ) ) {
 251                         // this is apparently a protocol-relative URL, which makes no sense in this context,
 252                         // since this is used for communication that's internal to the application.
 253                         // default to http.
 254                         $scalerBaseUrl = wfExpandUrl( $scalerBaseUrl, PROTO_CANONICAL );
 255                 }
 256
 257                 // We need to use generateThumbName() instead of thumbName(), because
 258                 // the suffix needs to match the file name for the remote thumbnailer
 259                 // to work
 260                 $scalerThumbName = $file->generateThumbName( $file->getName(), $params );
 261                 $scalerThumbUrl = $scalerBaseUrl . '/' . $file->getUrlRel() .
 262                         '/' . rawurlencode( $scalerThumbName );
 263
 264                 // make an http request based on wgUploadStashScalerBaseUrl to lazy-create
 265                 // a thumbnail
 266                 $httpOptions = [
 267                         'method' => 'GET',
 268                         'timeout' => 5 // T90599 attempt to time out cleanly
 269                 ];
 270                 $req = MWHttpRequest::factory( $scalerThumbUrl, $httpOptions, __METHOD__ );
 271                 $status = $req->execute();
 272                 if ( !$status->isOK() ) {
 273                         $errors = $status->getErrorsArray();
 274                         throw new UploadStashFileNotFoundException(
 275                                 $this->msg(
 276                                         'uploadstash-file-not-found-no-remote-thumb',
 277                                         print_r( $errors, 1 ),
 278                                         $scalerThumbUrl
 279                                 )
 280                         );
 281                 }
 282                 $contentType = $req->getResponseHeader( "content-type" );
 283                 if ( !$contentType ) {
 284                         throw new UploadStashFileNotFoundException(
 285                                 $this->msg( 'uploadstash-file-not-found-missing-content-type' )
 286                         );
 287                 }
 288
 289                 return $this->outputContents( $req->getContent(), $contentType );
 290         }
 291
 292         /**
 293          * Output HTTP response for file
 294          * Side effect: writes HTTP response to STDOUT.
 295          *
 296          * @param File $file File object with a local path (e.g. UnregisteredLocalFile,
 297          *   LocalFile. Oddly these don't share an ancestor!)
 298          * @throws SpecialUploadStashTooLargeException
 299          * @return bool
 300          */
 301         private function outputLocalFile( File $file ) {
 302                 if ( $file->getSize() > self::MAX_SERVE_BYTES ) {
 303                         throw new SpecialUploadStashTooLargeException(
 304                                 $this->msg( 'uploadstash-file-too-large', self::MAX_SERVE_BYTES )
 305                         );
 306                 }
 307
 308                 return $file->getRepo()->streamFile( $file->getPath(),
 309                         [ 'Content-Transfer-Encoding: binary',
 310                                 'Expires: Sun, 17-Jan-2038 19:14:07 GMT' ]
 311                 );
 312         }
 313
 314         /**
 315          * Output HTTP response of raw content
 316          * Side effect: writes HTTP response to STDOUT.
 317          * @param string $content
 318          * @param string $contentType MIME type
 319          * @throws SpecialUploadStashTooLargeException
 320          * @return bool
 321          */
 322         private function outputContents( $content, $contentType ) {
 323                 $size = strlen( $content );
 324                 if ( $size > self::MAX_SERVE_BYTES ) {
 325                         throw new SpecialUploadStashTooLargeException(
 326                                 $this->msg( 'uploadstash-file-too-large', self::MAX_SERVE_BYTES )
 327                         );
 328                 }
 329                 // Cancel output buffering and gzipping if set
 330                 wfResetOutputBuffers();
 331                 self::outputFileHeaders( $contentType, $size );
 332                 print $content;
 333
 334                 return true;
 335         }
 336
 337         /**
 338          * Output headers for streaming
 339          * @todo Unsure about encoding as binary; if we received from HTTP perhaps
 340          * we should use that encoding, concatenated with semicolon to `$contentType` as it
 341          * usually is.
 342          * Side effect: preps PHP to write headers to STDOUT.
 343          * @param string $contentType String suitable for content-type header
 344          * @param string $size Length in bytes
 345          */
 346         private static function outputFileHeaders( $contentType, $size ) {
 347                 header( "Content-Type: $contentType", true );
 348                 header( 'Content-Transfer-Encoding: binary', true );
 349                 header( 'Expires: Sun, 17-Jan-2038 19:14:07 GMT', true );
 350                 // T55032 - It shouldn't be a problem here, but let's be safe and not cache
 351                 header( 'Cache-Control: private' );
 352                 header( "Content-Length: $size", true );
 353         }
 354
 355         /**
 356          * Static callback for the HTMLForm in showUploads, to process
 357          * Note the stash has to be recreated since this is being called in a static context.
 358          * This works, because there really is only one stash per logged-in user, despite appearances.
 359          *
 360          * @param array $formData
 361          * @param HTMLForm $form
 362          * @return Status
 363          */
 364         public static function tryClearStashedUploads( $formData, $form ) {
 365                 if ( isset( $formData['Clear'] ) ) {
 366                         $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $form->getUser() );
 367                         wfDebug( 'stash has: ' . print_r( $stash->listFiles(), true ) . "\n" );
 368
 369                         if ( !$stash->clear() ) {
 370                                 return Status::newFatal( 'uploadstash-errclear' );
 371                         }
 372                 }
 373
 374                 return Status::newGood();
 375         }
 376
 377         /**
 378          * Default action when we don't have a subpage -- just show links to the uploads we have,
 379          * Also show a button to clear stashed files
 380          * @return bool
 381          */
 382         private function showUploads() {
 383                 // sets the title, etc.
 384                 $this->setHeaders();
 385                 $this->outputHeader();
 386
 387                 // create the form, which will also be used to execute a callback to process incoming form data
 388                 // this design is extremely dubious, but supposedly HTMLForm is our standard now?
 389
 390                 $context = new DerivativeContext( $this->getContext() );
 391                 $context->setTitle( $this->getPageTitle() ); // Remove subpage
 392                 $form = HTMLForm::factory( 'ooui', [
 393                         'Clear' => [
 394                                 'type' => 'hidden',
 395                                 'default' => true,
 396                                 'name' => 'clear',
 397                         ]
 398                 ], $context, 'clearStashedUploads' );
 399                 $form->setSubmitDestructive();
 400                 $form->setSubmitCallback( [ __CLASS__, 'tryClearStashedUploads' ] );
 401                 $form->setSubmitTextMsg( 'uploadstash-clear' );
 402
 403                 $form->prepareForm();
 404                 $formResult = $form->tryAuthorizedSubmit();
 405
 406                 // show the files + form, if there are any, or just say there are none
 407                 $refreshHtml = Html::element( 'a',
 408                         [ 'href' => $this->getPageTitle()->getLocalURL() ],
 409                         $this->msg( 'uploadstash-refresh' )->text() );
 410                 $files = $this->stash->listFiles();
 411                 if ( $files && count( $files ) ) {
 412                         sort( $files );
 413                         $fileListItemsHtml = '';
 414                         $linkRenderer = $this->getLinkRenderer();
 415                         foreach ( $files as $file ) {
 416                                 $itemHtml = $linkRenderer->makeKnownLink(
 417                                         $this->getPageTitle( "file/$file" ),
 418                                         $file
 419                                 );
 420                                 try {
 421                                         $fileObj = $this->stash->getFile( $file );
 422                                         $thumb = $fileObj->generateThumbName( $file, [ 'width' => 220 ] );
 423                                         $itemHtml .=
 424                                                 $this->msg( 'word-separator' )->escaped() .
 425                                                 $this->msg( 'parentheses' )->rawParams(
 426                                                         $linkRenderer->makeKnownLink(
 427                                                                 $this->getPageTitle( "thumb/$file/$thumb" ),
 428                                                                 $this->msg( 'uploadstash-thumbnail' )->text()
 429                                                         )
 430                                                 )->escaped();
 431                                 } catch ( Exception $e ) {
 432                                 }
 433                                 $fileListItemsHtml .= Html::rawElement( 'li', [], $itemHtml );
 434                         }
 435                         $this->getOutput()->addHTML( Html::rawElement( 'ul', [], $fileListItemsHtml ) );
 436                         $form->displayForm( $formResult );
 437                         $this->getOutput()->addHTML( Html::rawElement( 'p', [], $refreshHtml ) );
 438                 } else {
 439                         $this->getOutput()->addHTML( Html::rawElement( 'p', [],
 440                                 Html::element( 'span', [], $this->msg( 'uploadstash-nofiles' )->text() )
 441                                 . ' '
 442                                 . $refreshHtml
 443                         ) );
 444                 }
 445
 446                 return true;
 447         }
 448 }