3 * Implements Special:UploadStash
5 * Web access for files temporarily stored by UploadStash.
7 * For example -- files that were uploaded with the UploadWizard extension are stored temporarily
8 * before committing them to the db. But we want to see their thumbnails and get other information
11 * Since this is based on the user's session, in effect this creates a private temporary file area.
12 * However, the URLs for the files cannot be shared.
15 * @ingroup SpecialPage
19 class SpecialUploadStash
extends UnlistedSpecialPage
{
23 // Since we are directly writing the file to STDOUT,
24 // we should not be reading in really big files and serving them out.
26 // We also don't want people using this as a file drop, even if they
29 // This service is really for thumbnails and other such previews while
31 const MAX_SERVE_BYTES
= 262144; // 256K
33 public function __construct() {
34 parent
::__construct( 'UploadStash', 'upload' );
36 $this->stash
= RepoGroup
::singleton()->getLocalRepo()->getUploadStash();
37 } catch ( UploadStashNotAvailableException
$e ) {
43 * Execute page -- can output a file directly or show a listing of them.
45 * @param $subPage String: subpage, e.g. in http://example.com/wiki/Special:UploadStash/foo.jpg, the "foo.jpg" part
46 * @return Boolean: success
48 public function execute( $subPage ) {
51 if ( !$this->userCanExecute( $wgUser ) ) {
52 $this->displayRestrictionError();
56 if ( !isset( $subPage ) ||
$subPage === '' ) {
57 return $this->showUploads();
60 return $this->showUpload( $subPage );
65 * If file available in stash, cats it out to the client as a simple HTTP response.
66 * n.b. Most sanity checking done in UploadStashLocalFile, so this is straightforward.
68 * @param $key String: the key of a particular requested file
70 public function showUpload( $key ) {
73 // prevent callers from doing standard HTML output -- we'll take it from here
77 $params = $this->parseKey( $key );
78 if ( $params['type'] === 'thumb' ) {
79 return $this->outputThumbFromStash( $params['file'], $params['params'] );
81 return $this->outputLocalFile( $params['file'] );
83 } catch( UploadStashFileNotFoundException
$e ) {
85 $message = $e->getMessage();
86 } catch( UploadStashZeroLengthFileException
$e ) {
88 $message = $e->getMessage();
89 } catch( UploadStashBadPathException
$e ) {
91 $message = $e->getMessage();
92 } catch( SpecialUploadStashTooLargeException
$e ) {
94 $message = 'Cannot serve a file larger than ' . self
::MAX_SERVE_BYTES
. ' bytes. ' . $e->getMessage();
95 } catch( Exception
$e ) {
97 $message = $e->getMessage();
100 wfHttpError( $code, OutputPage
::getStatusMessage( $code ), $message );
105 * Parse the key passed to the SpecialPage. Returns an array containing
106 * the associated file object, the type ('file' or 'thumb') and if
107 * application the transform parameters
112 private function parseKey( $key ) {
113 $type = strtok( $key, '/' );
115 if ( $type !== 'file' && $type !== 'thumb' ) {
116 throw new UploadStashBadPathException( "Unknown type '$type'" );
118 $fileName = strtok( '/' );
119 $thumbPart = strtok( '/' );
120 $file = $this->stash
->getFile( $fileName );
121 if ( $type === 'thumb' ) {
122 $srcNamePos = strrpos( $thumbPart, $fileName );
123 if ( $srcNamePos === false ||
$srcNamePos < 1 ) {
124 throw new UploadStashBadPathException( 'Unrecognized thumb name' );
126 $paramString = substr( $thumbPart, 0, $srcNamePos - 1 );
128 $handler = $file->getHandler();
129 $params = $handler->parseParamString( $paramString );
130 return array( 'file' => $file, 'type' => $type, 'params' => $params );
133 return array( 'file' => $file, 'type' => $type );
140 * Get a thumbnail for file, either generated locally or remotely, and stream it out
141 * @param String $key: key for the file in the stash
142 * @param int $width: width of desired thumbnail
143 * @return boolean success
145 private function outputThumbFromStash( $file, $params ) {
147 // this global, if it exists, points to a "scaler", as you might find in the Wikimedia Foundation cluster. See outputRemoteScaledThumb()
148 // this is part of our horrible NFS-based system, we create a file on a mount point here, but fetch the scaled file from somewhere else that
149 // happens to share it over NFS
150 global $wgUploadStashScalerBaseUrl;
153 if ( $wgUploadStashScalerBaseUrl ) {
154 $this->outputRemoteScaledThumb( $file, $params, $flags );
156 $this->outputLocallyScaledThumb( $file, $params, $flags );
164 * Scale a file (probably with a locally installed imagemagick, or similar) and output it to STDOUT.
165 * @param $file: File object
166 * @param $params: scaling parameters ( e.g. array( width => '50' ) );
167 * @param $flags: scaling flags ( see File:: constants )
168 * @throws MWException
169 * @return boolean success
171 private function outputLocallyScaledThumb( $file, $params, $flags ) {
173 // n.b. this is stupid, we insist on re-transforming the file every time we are invoked. We rely
174 // on HTTP caching to ensure this doesn't happen.
176 $flags |
= File
::RENDER_NOW
;
178 $thumbnailImage = $file->transform( $params, $flags );
179 if ( !$thumbnailImage ) {
180 throw new MWException( 'Could not obtain thumbnail' );
183 // we should have just generated it locally
184 if ( ! $thumbnailImage->getPath() ) {
185 throw new UploadStashFileNotFoundException( "no local path for scaled item" );
188 // now we should construct a File, so we can get mime and other such info in a standard way
189 // n.b. mimetype may be different from original (ogx original -> jpeg thumb)
190 $thumbFile = new UnregisteredLocalFile( false, $this->stash
->repo
, $thumbnailImage->getPath(), false );
191 if ( ! $thumbFile ) {
192 throw new UploadStashFileNotFoundException( "couldn't create local file object for thumbnail" );
195 return $this->outputLocalFile( $thumbFile );
200 * Scale a file with a remote "scaler", as exists on the Wikimedia Foundation cluster, and output it to STDOUT.
201 * Note: unlike the usual thumbnail process, the web client never sees the cluster URL; we do the whole HTTP transaction to the scaler ourselves
202 * and cat the results out.
203 * Note: We rely on NFS to have propagated the file contents to the scaler. However, we do not rely on the thumbnail being created in NFS and then
204 * propagated back to our filesystem. Instead we take the results of the HTTP request instead.
205 * Note: no caching is being done here, although we are instructing the client to cache it forever.
206 * @param $file: File object
207 * @param $params: scaling parameters ( e.g. array( width => '50' ) );
208 * @param $flags: scaling flags ( see File:: constants )
209 * @throws MWException
210 * @return boolean success
212 private function outputRemoteScaledThumb( $file, $params, $flags ) {
214 // this global probably looks something like 'http://upload.wikimedia.org/wikipedia/test/thumb/temp'
215 // do not use trailing slash
216 global $wgUploadStashScalerBaseUrl;
218 $scalerThumbName = $file->getParamThumbName( $file->name
, $params );
219 $scalerThumbUrl = $wgUploadStashScalerBaseUrl . '/' . $file->getRel() . '/' . $scalerThumbName;
221 // make a curl call to the scaler to create a thumbnail
222 $httpOptions = array(
224 'timeout' => 'default'
226 $req = MWHttpRequest
::factory( $scalerThumbUrl, $httpOptions );
227 $status = $req->execute();
228 if ( ! $status->isOK() ) {
229 $errors = $status->getErrorsArray();
230 throw new MWException( "Fetching thumbnail failed: " . join( ", ", $errors ) );
232 $contentType = $req->getResponseHeader( "content-type" );
233 if ( ! $contentType ) {
234 throw new MWException( "Missing content-type header" );
236 return $this->outputContents( $req->getContent(), $contentType );
240 * Output HTTP response for file
241 * Side effect: writes HTTP response to STDOUT.
242 * XXX could use wfStreamfile (in includes/Streamfile.php), but for consistency with outputContents() doing it this way.
243 * XXX is mimeType really enough, or do we need encoding for full Content-Type header?
245 * @param $file File object with a local path (e.g. UnregisteredLocalFile, LocalFile. Oddly these don't share an ancestor!)
247 private function outputLocalFile( $file ) {
248 if ( $file->getSize() > self
::MAX_SERVE_BYTES
) {
249 throw new SpecialUploadStashTooLargeException();
251 self
::outputFileHeaders( $file->getMimeType(), $file->getSize() );
252 readfile( $file->getPath() );
257 * Output HTTP response of raw content
258 * Side effect: writes HTTP response to STDOUT.
259 * @param String $content: content
260 * @param String $mimeType: mime type
262 private function outputContents( $content, $contentType ) {
263 $size = strlen( $content );
264 if ( $size > self
::MAX_SERVE_BYTES
) {
265 throw new SpecialUploadStashTooLargeException();
267 self
::outputFileHeaders( $contentType, $size );
273 * Output headers for streaming
274 * XXX unsure about encoding as binary; if we received from HTTP perhaps we should use that encoding, concatted with semicolon to mimeType as it usually is.
275 * Side effect: preps PHP to write headers to STDOUT.
276 * @param String $contentType : string suitable for content-type header
277 * @param String $size: length in bytes
279 private static function outputFileHeaders( $contentType, $size ) {
280 header( "Content-Type: $contentType", true );
281 header( 'Content-Transfer-Encoding: binary', true );
282 header( 'Expires: Sun, 17-Jan-2038 19:14:07 GMT', true );
283 header( "Content-Length: $size", true );
287 * Static callback for the HTMLForm in showUploads, to process
288 * Note the stash has to be recreated since this is being called in a static context.
289 * This works, because there really is only one stash per logged-in user, despite appearances.
293 public static function tryClearStashedUploads( $formData ) {
294 if ( isset( $formData['Clear'] ) ) {
295 $stash = RepoGroup
::singleton()->getLocalRepo()->getUploadStash();
296 wfDebug( "stash has: " . print_r( $stash->listFiles(), true ) );
297 if ( ! $stash->clear() ) {
298 return Status
::newFatal( 'uploadstash-errclear' );
301 return Status
::newGood();
305 * Default action when we don't have a subpage -- just show links to the uploads we have,
306 * Also show a button to clear stashed files
307 * @param Status : $status - the result of processRequest
309 private function showUploads( $status = null ) {
311 if ( $status === null ) {
312 $status = Status
::newGood();
315 // sets the title, etc.
317 $this->outputHeader();
320 // create the form, which will also be used to execute a callback to process incoming form data
321 // this design is extremely dubious, but supposedly HTMLForm is our standard now?
323 $form = new HTMLForm( array(
329 ), 'clearStashedUploads' );
330 $form->setSubmitCallback( array( __CLASS__
, 'tryClearStashedUploads' ) );
331 $form->setTitle( $this->getTitle() );
332 $form->setSubmitText( wfMsg( 'uploadstash-clear' ) );
334 $form->prepareForm();
335 $formResult = $form->tryAuthorizedSubmit();
338 // show the files + form, if there are any, or just say there are none
339 $refreshHtml = Html
::element( 'a',
340 array( 'href' => $this->getTitle()->getLocalURL() ),
341 wfMsg( 'uploadstash-refresh' ) );
342 $files = $this->stash
->listFiles();
343 if ( count( $files ) ) {
345 $fileListItemsHtml = '';
346 foreach ( $files as $file ) {
347 // TODO: Use Linker::link or even construct the list in plain wikitext
348 $fileListItemsHtml .= Html
::rawElement( 'li', array(),
349 Html
::element( 'a', array( 'href' =>
350 $this->getTitle( "file/$file" )->getLocalURL() ), $file )
353 $wgOut->addHtml( Html
::rawElement( 'ul', array(), $fileListItemsHtml ) );
354 $form->displayForm( $formResult );
355 $wgOut->addHtml( Html
::rawElement( 'p', array(), $refreshHtml ) );
357 $wgOut->addHtml( Html
::rawElement( 'p', array(),
358 Html
::element( 'span', array(), wfMsg( 'uploadstash-nofiles' ) )
368 class SpecialUploadStashTooLargeException
extends MWException
{};