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SvgHandler.php
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1 <?php
26 
32 class SvgHandler extends ImageHandler {
34 
39  private static $metaConversion = [
40  'originalwidth' => 'ImageWidth',
41  'originalheight' => 'ImageLength',
42  'description' => 'ImageDescription',
43  'title' => 'ObjectName',
44  ];
45 
46  public function isEnabled() {
48  if ( !isset( $wgSVGConverters[$wgSVGConverter] ) ) {
49  wfDebug( "\$wgSVGConverter is invalid, disabling SVG rendering.\n" );
50 
51  return false;
52  } else {
53  return true;
54  }
55  }
56 
57  public function mustRender( $file ) {
58  return true;
59  }
60 
61  function isVectorized( $file ) {
62  return true;
63  }
64 
69  function isAnimatedImage( $file ) {
70  # @todo Detect animated SVGs
71  $metadata = $file->getMetadata();
72  if ( $metadata ) {
73  $metadata = $this->unpackMetadata( $metadata );
74  if ( isset( $metadata['animated'] ) ) {
75  return $metadata['animated'];
76  }
77  }
78 
79  return false;
80  }
81 
94  public function getAvailableLanguages( File $file ) {
95  $metadata = $file->getMetadata();
96  $langList = [];
97  if ( $metadata ) {
98  $metadata = $this->unpackMetadata( $metadata );
99  if ( isset( $metadata['translations'] ) ) {
100  foreach ( $metadata['translations'] as $lang => $langType ) {
101  if ( $langType === SVGReader::LANG_FULL_MATCH ) {
102  $langList[] = strtolower( $lang );
103  }
104  }
105  }
106  }
107  return array_unique( $langList );
108  }
109 
125  public function getMatchedLanguage( $userPreferredLanguage, array $svgLanguages ) {
126  foreach ( $svgLanguages as $svgLang ) {
127  if ( strcasecmp( $svgLang, $userPreferredLanguage ) === 0 ) {
128  return $svgLang;
129  }
130  $trimmedSvgLang = $svgLang;
131  while ( strpos( $trimmedSvgLang, '-' ) !== false ) {
132  $trimmedSvgLang = substr( $trimmedSvgLang, 0, strrpos( $trimmedSvgLang, '-' ) );
133  if ( strcasecmp( $trimmedSvgLang, $userPreferredLanguage ) === 0 ) {
134  return $svgLang;
135  }
136  }
137  }
138  return null;
139  }
140 
147  protected function getLanguageFromParams( array $params ) {
148  return $params['lang'] ?? $params['targetlang'] ?? 'en';
149  }
150 
157  public function getDefaultRenderLanguage( File $file ) {
158  return 'en';
159  }
160 
167  return false;
168  }
169 
175  public function normaliseParams( $image, &$params ) {
176  if ( parent::normaliseParams( $image, $params ) ) {
177  $params = $this->normaliseParamsInternal( $image, $params );
178  return true;
179  }
180 
181  return false;
182  }
183 
193  protected function normaliseParamsInternal( $image, $params ) {
194  global $wgSVGMaxSize;
195 
196  # Don't make an image bigger than wgMaxSVGSize on the smaller side
197  if ( $params['physicalWidth'] <= $params['physicalHeight'] ) {
198  if ( $params['physicalWidth'] > $wgSVGMaxSize ) {
199  $srcWidth = $image->getWidth( $params['page'] );
200  $srcHeight = $image->getHeight( $params['page'] );
201  $params['physicalWidth'] = $wgSVGMaxSize;
202  $params['physicalHeight'] = File::scaleHeight( $srcWidth, $srcHeight, $wgSVGMaxSize );
203  }
204  } elseif ( $params['physicalHeight'] > $wgSVGMaxSize ) {
205  $srcWidth = $image->getWidth( $params['page'] );
206  $srcHeight = $image->getHeight( $params['page'] );
207  $params['physicalWidth'] = File::scaleHeight( $srcHeight, $srcWidth, $wgSVGMaxSize );
208  $params['physicalHeight'] = $wgSVGMaxSize;
209  }
210  // To prevent the proliferation of thumbnails in languages not present in SVGs, unless
211  // explicitly forced by user.
212  if ( isset( $params['targetlang'] ) && !$image->getMatchedLanguage( $params['targetlang'] ) ) {
213  unset( $params['targetlang'] );
214  }
215 
216  return $params;
217  }
218 
227  function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
228  if ( !$this->normaliseParams( $image, $params ) ) {
229  return new TransformParameterError( $params );
230  }
231  $clientWidth = $params['width'];
232  $clientHeight = $params['height'];
233  $physicalWidth = $params['physicalWidth'];
234  $physicalHeight = $params['physicalHeight'];
235  $lang = $this->getLanguageFromParams( $params );
236 
237  if ( $flags & self::TRANSFORM_LATER ) {
238  return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
239  }
240 
241  $metadata = $this->unpackMetadata( $image->getMetadata() );
242  if ( isset( $metadata['error'] ) ) { // sanity check
243  $err = wfMessage( 'svg-long-error', $metadata['error']['message'] );
244 
245  return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
246  }
247 
248  if ( !wfMkdirParents( dirname( $dstPath ), null, __METHOD__ ) ) {
249  return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight,
250  wfMessage( 'thumbnail_dest_directory' ) );
251  }
252 
253  $srcPath = $image->getLocalRefPath();
254  if ( $srcPath === false ) { // Failed to get local copy
255  wfDebugLog( 'thumbnail',
256  sprintf( 'Thumbnail failed on %s: could not get local copy of "%s"',
257  wfHostname(), $image->getName() ) );
258 
259  return new MediaTransformError( 'thumbnail_error',
260  $params['width'], $params['height'],
261  wfMessage( 'filemissing' )
262  );
263  }
264 
265  // Make a temp dir with a symlink to the local copy in it.
266  // This plays well with rsvg-convert policy for external entities.
267  // https://git.gnome.org/browse/librsvg/commit/?id=f01aded72c38f0e18bc7ff67dee800e380251c8e
268  $tmpDir = wfTempDir() . '/svg_' . wfRandomString( 24 );
269  $lnPath = "$tmpDir/" . basename( $srcPath );
270  $ok = mkdir( $tmpDir, 0771 );
271  if ( !$ok ) {
272  wfDebugLog( 'thumbnail',
273  sprintf( 'Thumbnail failed on %s: could not create temporary directory %s',
274  wfHostname(), $tmpDir ) );
275  return new MediaTransformError( 'thumbnail_error',
276  $params['width'], $params['height'],
277  wfMessage( 'thumbnail-temp-create' )->text()
278  );
279  }
280  $ok = symlink( $srcPath, $lnPath );
282  $cleaner = new ScopedCallback( function () use ( $tmpDir, $lnPath ) {
283  Wikimedia\suppressWarnings();
284  unlink( $lnPath );
285  rmdir( $tmpDir );
286  Wikimedia\restoreWarnings();
287  } );
288  if ( !$ok ) {
289  wfDebugLog( 'thumbnail',
290  sprintf( 'Thumbnail failed on %s: could not link %s to %s',
291  wfHostname(), $lnPath, $srcPath ) );
292  return new MediaTransformError( 'thumbnail_error',
293  $params['width'], $params['height'],
294  wfMessage( 'thumbnail-temp-create' )
295  );
296  }
297 
298  $status = $this->rasterize( $lnPath, $dstPath, $physicalWidth, $physicalHeight, $lang );
299  if ( $status === true ) {
300  return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
301  } else {
302  return $status; // MediaTransformError
303  }
304  }
305 
317  public function rasterize( $srcPath, $dstPath, $width, $height, $lang = false ) {
319  $err = false;
320  $retval = '';
321  if ( isset( $wgSVGConverters[$wgSVGConverter] ) ) {
322  if ( is_array( $wgSVGConverters[$wgSVGConverter] ) ) {
323  // This is a PHP callable
324  $func = $wgSVGConverters[$wgSVGConverter][0];
325  if ( !is_callable( $func ) ) {
326  throw new MWException( "$func is not callable" );
327  }
328  $err = $func( $srcPath,
329  $dstPath,
330  $width,
331  $height,
332  $lang,
333  ...array_slice( $wgSVGConverters[$wgSVGConverter], 1 )
334  );
335  $retval = (bool)$err;
336  } else {
337  // External command
338  $cmd = str_replace(
339  [ '$path/', '$width', '$height', '$input', '$output' ],
340  [ $wgSVGConverterPath ? Shell::escape( "$wgSVGConverterPath/" ) : "",
341  intval( $width ),
342  intval( $height ),
343  Shell::escape( $srcPath ),
344  Shell::escape( $dstPath ) ],
345  $wgSVGConverters[$wgSVGConverter]
346  );
347 
348  $env = [];
349  if ( $lang !== false ) {
350  $env['LANG'] = $lang;
351  }
352 
353  wfDebug( __METHOD__ . ": $cmd\n" );
354  $err = wfShellExecWithStderr( $cmd, $retval, $env );
355  }
356  }
357  $removed = $this->removeBadFile( $dstPath, $retval );
358  if ( $retval != 0 || $removed ) {
359  $this->logErrorForExternalProcess( $retval, $err, $cmd );
360  return new MediaTransformError( 'thumbnail_error', $width, $height, $err );
361  }
362 
363  return true;
364  }
365 
366  public static function rasterizeImagickExt( $srcPath, $dstPath, $width, $height ) {
367  $im = new Imagick( $srcPath );
368  $im->setImageFormat( 'png' );
369  $im->setBackgroundColor( 'transparent' );
370  $im->setImageDepth( 8 );
371 
372  if ( !$im->thumbnailImage( intval( $width ), intval( $height ), /* fit */ false ) ) {
373  return 'Could not resize image';
374  }
375  if ( !$im->writeImage( $dstPath ) ) {
376  return "Could not write to $dstPath";
377  }
378  }
379 
386  function getImageSize( $file, $path, $metadata = false ) {
387  if ( $metadata === false && $file instanceof File ) {
388  $metadata = $file->getMetadata();
389  }
390  $metadata = $this->unpackMetadata( $metadata );
391 
392  if ( isset( $metadata['width'] ) && isset( $metadata['height'] ) ) {
393  return [ $metadata['width'], $metadata['height'], 'SVG',
394  "width=\"{$metadata['width']}\" height=\"{$metadata['height']}\"" ];
395  } else { // error
396  return [ 0, 0, 'SVG', "width=\"0\" height=\"0\"" ];
397  }
398  }
399 
400  public function getThumbType( $ext, $mime, $params = null ) {
401  return [ 'png', 'image/png' ];
402  }
403 
413  public function getLongDesc( $file ) {
414  global $wgLang;
415 
416  $metadata = $this->unpackMetadata( $file->getMetadata() );
417  if ( isset( $metadata['error'] ) ) {
418  return wfMessage( 'svg-long-error', $metadata['error']['message'] )->text();
419  }
420 
421  $size = $wgLang->formatSize( $file->getSize() );
422 
423  if ( $this->isAnimatedImage( $file ) ) {
424  $msg = wfMessage( 'svg-long-desc-animated' );
425  } else {
426  $msg = wfMessage( 'svg-long-desc' );
427  }
428 
429  $msg->numParams( $file->getWidth(), $file->getHeight() )->params( $size );
430 
431  return $msg->parse();
432  }
433 
439  public function getMetadata( $file, $filename ) {
440  $metadata = [ 'version' => self::SVG_METADATA_VERSION ];
441 
442  try {
443  $svgReader = new SVGReader( $filename );
444  $metadata += $svgReader->getMetadata();
445  } catch ( Exception $e ) { // @todo SVG specific exceptions
446  // File not found, broken, etc.
447  $metadata['error'] = [
448  'message' => $e->getMessage(),
449  'code' => $e->getCode()
450  ];
451  wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
452  }
453 
454  return serialize( $metadata );
455  }
456 
457  function unpackMetadata( $metadata ) {
458  Wikimedia\suppressWarnings();
459  $unser = unserialize( $metadata );
460  Wikimedia\restoreWarnings();
461  if ( isset( $unser['version'] ) && $unser['version'] == self::SVG_METADATA_VERSION ) {
462  return $unser;
463  } else {
464  return false;
465  }
466  }
467 
468  function getMetadataType( $image ) {
469  return 'parsed-svg';
470  }
471 
472  public function isMetadataValid( $image, $metadata ) {
473  $meta = $this->unpackMetadata( $metadata );
474  if ( $meta === false ) {
475  return self::METADATA_BAD;
476  }
477  if ( !isset( $meta['originalWidth'] ) ) {
478  // Old but compatible
479  return self::METADATA_COMPATIBLE;
480  }
481 
482  return self::METADATA_GOOD;
483  }
484 
485  protected function visibleMetadataFields() {
486  $fields = [ 'objectname', 'imagedescription' ];
487 
488  return $fields;
489  }
490 
496  public function formatMetadata( $file, $context = false ) {
497  $result = [
498  'visible' => [],
499  'collapsed' => []
500  ];
501  $metadata = $file->getMetadata();
502  if ( !$metadata ) {
503  return false;
504  }
505  $metadata = $this->unpackMetadata( $metadata );
506  if ( !$metadata || isset( $metadata['error'] ) ) {
507  return false;
508  }
509 
510  /* @todo Add a formatter
511  $format = new FormatSVG( $metadata );
512  $formatted = $format->getFormattedData();
513  */
514 
515  // Sort fields into visible and collapsed
516  $visibleFields = $this->visibleMetadataFields();
517 
518  $showMeta = false;
519  foreach ( $metadata as $name => $value ) {
520  $tag = strtolower( $name );
521  if ( isset( self::$metaConversion[$tag] ) ) {
522  $tag = strtolower( self::$metaConversion[$tag] );
523  } else {
524  // Do not output other metadata not in list
525  continue;
526  }
527  $showMeta = true;
528  self::addMeta( $result,
529  in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
530  'exif',
531  $tag,
532  $value
533  );
534  }
535 
536  return $showMeta ? $result : false;
537  }
538 
544  public function validateParam( $name, $value ) {
545  if ( in_array( $name, [ 'width', 'height' ] ) ) {
546  // Reject negative heights, widths
547  return ( $value > 0 );
548  } elseif ( $name == 'lang' ) {
549  // Validate $code
550  if ( $value === '' || !Language::isValidCode( $value ) ) {
551  return false;
552  }
553 
554  return true;
555  }
556 
557  // Only lang, width and height are acceptable keys
558  return false;
559  }
560 
565  public function makeParamString( $params ) {
566  $lang = '';
567  $code = $this->getLanguageFromParams( $params );
568  if ( $code !== 'en' ) {
569  $lang = 'lang' . strtolower( $code ) . '-';
570  }
571  if ( !isset( $params['width'] ) ) {
572  return false;
573  }
574 
575  return "$lang{$params['width']}px";
576  }
577 
578  public function parseParamString( $str ) {
579  $m = false;
580  if ( preg_match( '/^lang([a-z]+(?:-[a-z]+)*)-(\d+)px$/i', $str, $m ) ) {
581  return [ 'width' => array_pop( $m ), 'lang' => $m[1] ];
582  } elseif ( preg_match( '/^(\d+)px$/', $str, $m ) ) {
583  return [ 'width' => $m[1], 'lang' => 'en' ];
584  } else {
585  return false;
586  }
587  }
588 
589  public function getParamMap() {
590  return [ 'img_lang' => 'lang', 'img_width' => 'width' ];
591  }
592 
597  protected function getScriptParams( $params ) {
598  $scriptParams = [ 'width' => $params['width'] ];
599  if ( isset( $params['lang'] ) ) {
600  $scriptParams['lang'] = $params['lang'];
601  }
602 
603  return $scriptParams;
604  }
605 
606  public function getCommonMetaArray( File $file ) {
607  $metadata = $file->getMetadata();
608  if ( !$metadata ) {
609  return [];
610  }
611  $metadata = $this->unpackMetadata( $metadata );
612  if ( !$metadata || isset( $metadata['error'] ) ) {
613  return [];
614  }
615  $stdMetadata = [];
616  foreach ( $metadata as $name => $value ) {
617  $tag = strtolower( $name );
618  if ( $tag === 'originalwidth' || $tag === 'originalheight' ) {
619  // Skip these. In the exif metadata stuff, it is assumed these
620  // are measured in px, which is not the case here.
621  continue;
622  }
623  if ( isset( self::$metaConversion[$tag] ) ) {
624  $tag = self::$metaConversion[$tag];
625  $stdMetadata[$tag] = $value;
626  }
627  }
628 
629  return $stdMetadata;
630  }
631 }
if(PHP_SAPI !='cli-server') if(!isset( $_SERVER['SCRIPT_FILENAME'])) $file
Item class for a filearchive table row.
Definition: router.php:42
removeBadFile( $dstPath, $retval=0)
Check for zero-sized thumbnails.
isVectorized( $file)
Definition: SvgHandler.php:61
getAvailableLanguages(File $file)
Which languages (systemLanguage attribute) is supported.
Definition: SvgHandler.php:94
$context
Definition: load.php:40
serialize()
getMetadataType( $image)
Definition: SvgHandler.php:468
getMatchedLanguage( $userPreferredLanguage, array $svgLanguages)
SVG&#39;s systemLanguage matching rules state: &#39;The systemLanguage attribute ...
Definition: SvgHandler.php:125
unpackMetadata( $metadata)
Definition: SvgHandler.php:457
wfHostname()
Fetch server name for use in error reporting etc.
if(!isset( $args[0])) $lang
isAnimatedImage( $file)
Definition: SvgHandler.php:69
static scaleHeight( $srcWidth, $srcHeight, $dstWidth)
Calculate the height of a thumbnail using the source and destination width.
Definition: File.php:2014
getScriptParams( $params)
Definition: SvgHandler.php:597
makeParamString( $params)
Definition: SvgHandler.php:565
Shortcut class for parameter validation errors.
getLanguageFromParams(array $params)
Determines render language from image parameters.
Definition: SvgHandler.php:147
validateParam( $name, $value)
Definition: SvgHandler.php:544
getMetadata( $file, $filename)
Definition: SvgHandler.php:439
parseParamString( $str)
Definition: SvgHandler.php:578
$wgLang
Definition: Setup.php:858
wfTempDir()
Tries to get the system directory for temporary files.
$wgSVGConverterPath
If not in the executable PATH, specify the SVG converter path.
wfRandomString( $length=32)
Get a random string containing a number of pseudo-random hex characters.
getMetadata()
Get handler-specific metadata Overridden by LocalFile, UnregisteredLocalFile STUB.
Definition: File.php:663
const LANG_FULL_MATCH
Definition: SVGReader.php:36
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
$wgSVGConverters
Scalable Vector Graphics (SVG) may be uploaded as images.
Media transform output for images.
getCommonMetaArray(File $file)
Definition: SvgHandler.php:606
getThumbType( $ext, $mime, $params=null)
Definition: SvgHandler.php:400
unserialize( $serialized)
normaliseParams( $image, &$params)
Definition: SvgHandler.php:175
canAnimateThumbnail( $file)
We do not support making animated svg thumbnails.
Definition: SvgHandler.php:166
static array isEnabled()
Definition: SvgHandler.php:46
rasterize( $srcPath, $dstPath, $width, $height, $lang=false)
Transform an SVG file to PNG This function can be called outside of thumbnail contexts.
Definition: SvgHandler.php:317
$wgSVGMaxSize
Don&#39;t scale a SVG larger than this.
const SVG_METADATA_VERSION
Definition: SvgHandler.php:33
getLongDesc( $file)
Subtitle for the image.
Definition: SvgHandler.php:413
normaliseParamsInternal( $image, $params)
Code taken out of normaliseParams() for testability.
Definition: SvgHandler.php:193
visibleMetadataFields()
Definition: SvgHandler.php:485
Media handler abstract base class for images.
wfMkdirParents( $dir, $mode=null, $caller=null)
Make directory, and make all parent directories if they don&#39;t exist.
wfDebugLog( $logGroup, $text, $dest='all', array $context=[])
Send a line to a supplementary debug log file, if configured, or main debug log if not...
logErrorForExternalProcess( $retval, $err, $cmd)
Log an error that occurred in an external process.
static rasterizeImagickExt( $srcPath, $dstPath, $width, $height)
Definition: SvgHandler.php:366
formatMetadata( $file, $context=false)
Definition: SvgHandler.php:496
wfShellExecWithStderr( $cmd, &$retval=null, $environ=[], $limits=[])
Execute a shell command, returning both stdout and stderr.
if(!is_readable( $file)) $ext
Definition: router.php:48
getDefaultRenderLanguage(File $file)
What language to render file in if none selected.
Definition: SvgHandler.php:157
doTransform( $image, $dstPath, $dstUrl, $params, $flags=0)
Definition: SvgHandler.php:227
getImageSize( $file, $path, $metadata=false)
Definition: SvgHandler.php:386
static array $metaConversion
A list of metadata tags that can be converted to the commonly used exif tags.
Definition: SvgHandler.php:39
mustRender( $file)
Definition: SvgHandler.php:57
wfMessage( $key,... $params)
This is the function for getting translated interface messages.
Implements some public methods and some protected utility functions which are required by multiple ch...
Definition: File.php:61
static isValidCode( $code)
Returns true if a language code string is of a valid form, whether or not it exists.
Definition: Language.php:405
$wgSVGConverter
Pick a converter defined in $wgSVGConverters.
isMetadataValid( $image, $metadata)
Definition: SvgHandler.php:472
Handler for SVG images.
Definition: SvgHandler.php:32
Basic media transform error class.