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