MediaWiki  master
SvgHandler.php
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1 <?php
27 use Wikimedia\AtEase\AtEase;
28 use Wikimedia\RequestTimeout\TimeoutException;
29 use Wikimedia\ScopedCallback;
30 
36 class SvgHandler extends ImageHandler {
37  public const SVG_METADATA_VERSION = 2;
38 
39  private const SVG_DEFAULT_RENDER_LANG = 'en';
40 
45  private static $metaConversion = [
46  'originalwidth' => 'ImageWidth',
47  'originalheight' => 'ImageLength',
48  'description' => 'ImageDescription',
49  'title' => 'ObjectName',
50  ];
51 
52  public function isEnabled() {
53  $svgConverters = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::SVGConverters );
54  $svgConverter = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::SVGConverter );
55  if ( !isset( $svgConverters[$svgConverter] ) ) {
56  wfDebug( "\$wgSVGConverter is invalid, disabling SVG rendering." );
57 
58  return false;
59  } else {
60  return true;
61  }
62  }
63 
64  public function mustRender( $file ) {
65  return true;
66  }
67 
68  public function isVectorized( $file ) {
69  return true;
70  }
71 
76  public function isAnimatedImage( $file ) {
77  # @todo Detect animated SVGs
78  $metadata = $this->validateMetadata( $file->getMetadataArray() );
79  if ( isset( $metadata['animated'] ) ) {
80  return $metadata['animated'];
81  }
82 
83  return false;
84  }
85 
98  public function getAvailableLanguages( File $file ) {
99  $langList = [];
100  $metadata = $this->validateMetadata( $file->getMetadataArray() );
101  if ( isset( $metadata['translations'] ) ) {
102  foreach ( $metadata['translations'] as $lang => $langType ) {
103  if ( $langType === SVGReader::LANG_FULL_MATCH ) {
104  $langList[] = strtolower( $lang );
105  }
106  }
107  }
108  return array_unique( $langList );
109  }
110 
126  public function getMatchedLanguage( $userPreferredLanguage, array $svgLanguages ) {
127  // Explicitly requested undetermined language (text without svg systemLanguage attribute)
128  if ( $userPreferredLanguage === 'und' ) {
129  return 'und';
130  }
131  foreach ( $svgLanguages as $svgLang ) {
132  if ( strcasecmp( $svgLang, $userPreferredLanguage ) === 0 ) {
133  return $svgLang;
134  }
135  $trimmedSvgLang = $svgLang;
136  while ( strpos( $trimmedSvgLang, '-' ) !== false ) {
137  $trimmedSvgLang = substr( $trimmedSvgLang, 0, strrpos( $trimmedSvgLang, '-' ) );
138  if ( strcasecmp( $trimmedSvgLang, $userPreferredLanguage ) === 0 ) {
139  return $svgLang;
140  }
141  }
142  }
143  return null;
144  }
145 
153  protected function getLanguageFromParams( array $params ) {
154  return $params['lang'] ?? $params['targetlang'] ?? self::SVG_DEFAULT_RENDER_LANG;
155  }
156 
163  public function getDefaultRenderLanguage( File $file ) {
164  return self::SVG_DEFAULT_RENDER_LANG;
165  }
166 
172  public function canAnimateThumbnail( $file ) {
173  return false;
174  }
175 
181  public function normaliseParams( $image, &$params ) {
182  if ( parent::normaliseParams( $image, $params ) ) {
183  $params = $this->normaliseParamsInternal( $image, $params );
184  return true;
185  }
186 
187  return false;
188  }
189 
199  protected function normaliseParamsInternal( $image, $params ) {
200  $svgMaxSize = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::SVGMaxSize );
201 
202  # Don't make an image bigger than wgMaxSVGSize on the smaller side
203  if ( $params['physicalWidth'] <= $params['physicalHeight'] ) {
204  if ( $params['physicalWidth'] > $svgMaxSize ) {
205  $srcWidth = $image->getWidth( $params['page'] );
206  $srcHeight = $image->getHeight( $params['page'] );
207  $params['physicalWidth'] = $svgMaxSize;
208  $params['physicalHeight'] = File::scaleHeight( $srcWidth, $srcHeight, $svgMaxSize );
209  }
210  } elseif ( $params['physicalHeight'] > $svgMaxSize ) {
211  $srcWidth = $image->getWidth( $params['page'] );
212  $srcHeight = $image->getHeight( $params['page'] );
213  $params['physicalWidth'] = File::scaleHeight( $srcHeight, $srcWidth, $svgMaxSize );
214  $params['physicalHeight'] = $svgMaxSize;
215  }
216  // To prevent the proliferation of thumbnails in languages not present in SVGs, unless
217  // explicitly forced by user.
218  if ( isset( $params['targetlang'] ) && !$image->getMatchedLanguage( $params['targetlang'] ) ) {
219  unset( $params['targetlang'] );
220  }
221 
222  return $params;
223  }
224 
233  public function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
234  if ( !$this->normaliseParams( $image, $params ) ) {
235  return new TransformParameterError( $params );
236  }
237  $clientWidth = $params['width'];
238  $clientHeight = $params['height'];
239  $physicalWidth = $params['physicalWidth'];
240  $physicalHeight = $params['physicalHeight'];
241  $lang = $this->getLanguageFromParams( $params );
242 
243  if ( $flags & self::TRANSFORM_LATER ) {
244  return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
245  }
246 
247  $metadata = $this->validateMetadata( $image->getMetadataArray() );
248  if ( isset( $metadata['error'] ) ) {
249  $err = wfMessage( 'svg-long-error', $metadata['error']['message'] );
250 
251  return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
252  }
253 
254  if ( !wfMkdirParents( dirname( $dstPath ), null, __METHOD__ ) ) {
255  return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight,
256  wfMessage( 'thumbnail_dest_directory' ) );
257  }
258 
259  $srcPath = $image->getLocalRefPath();
260  if ( $srcPath === false ) { // Failed to get local copy
261  wfDebugLog( 'thumbnail',
262  sprintf( 'Thumbnail failed on %s: could not get local copy of "%s"',
263  wfHostname(), $image->getName() ) );
264 
265  return new MediaTransformError( 'thumbnail_error',
266  $params['width'], $params['height'],
267  wfMessage( 'filemissing' )
268  );
269  }
270 
271  // Make a temp dir with a symlink to the local copy in it.
272  // This plays well with rsvg-convert policy for external entities.
273  // https://git.gnome.org/browse/librsvg/commit/?id=f01aded72c38f0e18bc7ff67dee800e380251c8e
274  $tmpDir = wfTempDir() . '/svg_' . wfRandomString( 24 );
275  $lnPath = "$tmpDir/" . basename( $srcPath );
276  $ok = mkdir( $tmpDir, 0771 );
277  if ( !$ok ) {
278  wfDebugLog( 'thumbnail',
279  sprintf( 'Thumbnail failed on %s: could not create temporary directory %s',
280  wfHostname(), $tmpDir ) );
281  return new MediaTransformError( 'thumbnail_error',
282  $params['width'], $params['height'],
283  wfMessage( 'thumbnail-temp-create' )->text()
284  );
285  }
286  $ok = symlink( $srcPath, $lnPath );
288  $cleaner = new ScopedCallback( static function () use ( $tmpDir, $lnPath ) {
289  AtEase::suppressWarnings();
290  unlink( $lnPath );
291  rmdir( $tmpDir );
292  AtEase::restoreWarnings();
293  } );
294  if ( !$ok ) {
295  // Fallback because symlink often fails on Windows
296  $ok = copy( $srcPath, $lnPath );
297  }
298  if ( !$ok ) {
299  wfDebugLog( 'thumbnail',
300  sprintf( 'Thumbnail failed on %s: could not link %s to %s',
301  wfHostname(), $lnPath, $srcPath ) );
302  return new MediaTransformError( 'thumbnail_error',
303  $params['width'], $params['height'],
304  wfMessage( 'thumbnail-temp-create' )
305  );
306  }
307 
308  $status = $this->rasterize( $lnPath, $dstPath, $physicalWidth, $physicalHeight, $lang );
309  if ( $status === true ) {
310  return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
311  } else {
312  return $status; // MediaTransformError
313  }
314  }
315 
327  public function rasterize( $srcPath, $dstPath, $width, $height, $lang = false ) {
328  $mainConfig = MediaWikiServices::getInstance()->getMainConfig();
329  $svgConverters = $mainConfig->get( MainConfigNames::SVGConverters );
330  $svgConverter = $mainConfig->get( MainConfigNames::SVGConverter );
331  $svgConverterPath = $mainConfig->get( MainConfigNames::SVGConverterPath );
332  $err = false;
333  $retval = '';
334  if ( isset( $svgConverters[$svgConverter] ) ) {
335  if ( is_array( $svgConverters[$svgConverter] ) ) {
336  // This is a PHP callable
337  $func = $svgConverters[$svgConverter][0];
338  if ( !is_callable( $func ) ) {
339  throw new MWException( "$func is not callable" );
340  }
341  $err = $func( $srcPath,
342  $dstPath,
343  $width,
344  $height,
345  $lang,
346  ...array_slice( $svgConverters[$svgConverter], 1 )
347  );
348  $retval = (bool)$err;
349  } else {
350  // External command
351  $cmd = str_replace(
352  [ '$path/', '$width', '$height', '$input', '$output' ],
353  [ $svgConverterPath ? Shell::escape( "{$svgConverterPath}/" ) : "",
354  intval( $width ),
355  intval( $height ),
356  Shell::escape( $srcPath ),
357  Shell::escape( $dstPath ) ],
358  $svgConverters[$svgConverter]
359  );
360 
361  $env = [];
362  if ( $lang !== false ) {
363  $env['LANG'] = $lang;
364  }
365 
366  wfDebug( __METHOD__ . ": $cmd" );
367  $err = wfShellExecWithStderr( $cmd, $retval, $env );
368  }
369  }
370  $removed = $this->removeBadFile( $dstPath, $retval );
371  if ( $retval != 0 || $removed ) {
372  // @phan-suppress-next-next-line PhanPossiblyUndeclaredVariable cmd is set when used
373  // @phan-suppress-next-line PhanTypeMismatchArgumentNullable cmd is set when used
374  $this->logErrorForExternalProcess( $retval, $err, $cmd );
375  return new MediaTransformError( 'thumbnail_error', $width, $height, $err );
376  }
377 
378  return true;
379  }
380 
381  public static function rasterizeImagickExt( $srcPath, $dstPath, $width, $height ) {
382  $im = new Imagick( $srcPath );
383  $im->setBackgroundColor( 'transparent' );
384  $im->readImage( $srcPath );
385  $im->setImageFormat( 'png' );
386  $im->setImageDepth( 8 );
387 
388  if ( !$im->thumbnailImage( intval( $width ), intval( $height ), /* fit */ false ) ) {
389  return 'Could not resize image';
390  }
391  if ( !$im->writeImage( $dstPath ) ) {
392  return "Could not write to $dstPath";
393  }
394  }
395 
396  public function getThumbType( $ext, $mime, $params = null ) {
397  return [ 'png', 'image/png' ];
398  }
399 
409  public function getLongDesc( $file ) {
410  $metadata = $this->validateMetadata( $file->getMetadataArray() );
411  if ( isset( $metadata['error'] ) ) {
412  return wfMessage( 'svg-long-error', $metadata['error']['message'] )->text();
413  }
414 
415  if ( $this->isAnimatedImage( $file ) ) {
416  $msg = wfMessage( 'svg-long-desc-animated' );
417  } else {
418  $msg = wfMessage( 'svg-long-desc' );
419  }
420 
421  return $msg->numParams( $file->getWidth(), $file->getHeight() )->sizeParams( $file->getSize() )->parse();
422  }
423 
429  public function getSizeAndMetadata( $state, $filename ) {
430  $metadata = [ 'version' => self::SVG_METADATA_VERSION ];
431 
432  try {
433  $svgReader = new SVGReader( $filename );
434  $metadata += $svgReader->getMetadata();
435  } catch ( TimeoutException $e ) {
436  throw $e;
437  } catch ( Exception $e ) { // @todo SVG specific exceptions
438  // File not found, broken, etc.
439  $metadata['error'] = [
440  'message' => $e->getMessage(),
441  'code' => $e->getCode()
442  ];
443  wfDebug( __METHOD__ . ': ' . $e->getMessage() );
444  }
445 
446  return [
447  'width' => $metadata['width'] ?? 0,
448  'height' => $metadata['height'] ?? 0,
449  'metadata' => $metadata
450  ];
451  }
452 
453  protected function validateMetadata( $unser ) {
454  if ( isset( $unser['version'] ) && $unser['version'] == self::SVG_METADATA_VERSION ) {
455  return $unser;
456  } else {
457  return null;
458  }
459  }
460 
461  public function getMetadataType( $image ) {
462  return 'parsed-svg';
463  }
464 
465  public function isFileMetadataValid( $image ) {
466  $meta = $this->validateMetadata( $image->getMetadataArray() );
467  if ( !$meta ) {
468  return self::METADATA_BAD;
469  }
470  if ( !isset( $meta['originalWidth'] ) ) {
471  // Old but compatible
473  }
474 
475  return self::METADATA_GOOD;
476  }
477 
478  protected function visibleMetadataFields() {
479  $fields = [ 'objectname', 'imagedescription' ];
480 
481  return $fields;
482  }
483 
489  public function formatMetadata( $file, $context = false ) {
490  $result = [
491  'visible' => [],
492  'collapsed' => []
493  ];
494  $metadata = $this->validateMetadata( $file->getMetadataArray() );
495  if ( !$metadata || isset( $metadata['error'] ) ) {
496  return false;
497  }
498 
499  /* @todo Add a formatter
500  $format = new FormatSVG( $metadata );
501  $formatted = $format->getFormattedData();
502  */
503 
504  // Sort fields into visible and collapsed
505  $visibleFields = $this->visibleMetadataFields();
506 
507  $showMeta = false;
508  foreach ( $metadata as $name => $value ) {
509  $tag = strtolower( $name );
510  if ( isset( self::$metaConversion[$tag] ) ) {
511  $tag = strtolower( self::$metaConversion[$tag] );
512  } else {
513  // Do not output other metadata not in list
514  continue;
515  }
516  $showMeta = true;
517  self::addMeta( $result,
518  in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
519  'exif',
520  $tag,
521  $value
522  );
523  }
524 
525  return $showMeta ? $result : false;
526  }
527 
533  public function validateParam( $name, $value ) {
534  if ( in_array( $name, [ 'width', 'height' ] ) ) {
535  // Reject negative heights, widths
536  return ( $value > 0 );
537  }
538  if ( $name == 'lang' ) {
539  // Validate $code
540  if ( $value === ''
542  ) {
543  return false;
544  }
545 
546  return true;
547  }
548 
549  // Only lang, width and height are acceptable keys
550  return false;
551  }
552 
557  public function makeParamString( $params ) {
558  $lang = '';
559  $code = $this->getLanguageFromParams( $params );
560  if ( $code !== self::SVG_DEFAULT_RENDER_LANG ) {
561  $lang = 'lang' . strtolower( $code ) . '-';
562  }
563  if ( !isset( $params['width'] ) ) {
564  return false;
565  }
566 
567  return "$lang{$params['width']}px";
568  }
569 
570  public function parseParamString( $str ) {
571  $m = false;
572  // Language codes are supposed to be lowercase
573  if ( preg_match( '/^lang([a-z]+(?:-[a-z]+)*)-(\d+)px$/', $str, $m ) ) {
574  if ( LanguageCode::isWellFormedLanguageTag( $m[1] ) ) {
575  return [ 'width' => array_pop( $m ), 'lang' => $m[1] ];
576  }
577  return [ 'width' => array_pop( $m ), 'lang' => self::SVG_DEFAULT_RENDER_LANG ];
578  }
579  if ( preg_match( '/^(\d+)px$/', $str, $m ) ) {
580  return [ 'width' => $m[1], 'lang' => self::SVG_DEFAULT_RENDER_LANG ];
581  }
582  return false;
583  }
584 
585  public function getParamMap() {
586  return [ 'img_lang' => 'lang', 'img_width' => 'width' ];
587  }
588 
593  protected function getScriptParams( $params ) {
594  $scriptParams = [ 'width' => $params['width'] ];
595  if ( isset( $params['lang'] ) ) {
596  $scriptParams['lang'] = $params['lang'];
597  }
598 
599  return $scriptParams;
600  }
601 
602  public function getCommonMetaArray( File $file ) {
603  $metadata = $this->validateMetadata( $file->getMetadataArray() );
604  if ( !$metadata || isset( $metadata['error'] ) ) {
605  return [];
606  }
607  $stdMetadata = [];
608  foreach ( $metadata as $name => $value ) {
609  $tag = strtolower( $name );
610  if ( $tag === 'originalwidth' || $tag === 'originalheight' ) {
611  // Skip these. In the exif metadata stuff, it is assumed these
612  // are measured in px, which is not the case here.
613  continue;
614  }
615  if ( isset( self::$metaConversion[$tag] ) ) {
616  $tag = self::$metaConversion[$tag];
617  $stdMetadata[$tag] = $value;
618  }
619  }
620 
621  return $stdMetadata;
622  }
623 }
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
wfTempDir()
Tries to get the system directory for temporary files.
wfRandomString( $length=32)
Get a random string containing a number of pseudo-random hex characters.
wfHostname()
Get host name of the current machine, for use in error reporting.
wfShellExecWithStderr( $cmd, &$retval=null, $environ=[], $limits=[])
Execute a shell command, returning both stdout and stderr.
wfDebugLog( $logGroup, $text, $dest='all', array $context=[])
Send a line to a supplementary debug log file, if configured, or main debug log if not.
wfMkdirParents( $dir, $mode=null, $caller=null)
Make directory, and make all parent directories if they don't exist.
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:67
getMetadataArray()
Get the unserialized handler-specific metadata STUB.
Definition: File.php:750
static scaleHeight( $srcWidth, $srcHeight, $dstWidth)
Calculate the height of a thumbnail using the source and destination width.
Definition: File.php:2195
Media handler abstract base class for images.
static isWellFormedLanguageTag(string $code, bool $lenient=false)
Returns true if a language code string is a well-formed language tag according to RFC 5646.
MediaWiki exception.
Definition: MWException.php:29
const METADATA_COMPATIBLE
static addMeta(&$array, $visibility, $type, $id, $value, $param=false)
This is used to generate an array element for each metadata value That array is then used to generate...
const METADATA_BAD
logErrorForExternalProcess( $retval, $err, $cmd)
Log an error that occurred in an external process.
const METADATA_GOOD
removeBadFile( $dstPath, $retval=0)
Check for zero-sized thumbnails.
Basic media transform error class.
A class containing constants representing the names of configuration variables.
Service locator for MediaWiki core services.
Executes shell commands.
Definition: Shell.php:46
const LANG_FULL_MATCH
Definition: SVGReader.php:41
Handler for SVG images.
Definition: SvgHandler.php:36
validateParam( $name, $value)
Definition: SvgHandler.php:533
isVectorized( $file)
The material is vectorized and thus scaling is lossless.
Definition: SvgHandler.php:68
normaliseParams( $image, &$params)
Definition: SvgHandler.php:181
formatMetadata( $file, $context=false)
Definition: SvgHandler.php:489
parseParamString( $str)
Parse a param string made with makeParamString back into an array.The parameter string without file n...
Definition: SvgHandler.php:570
mustRender( $file)
True if handled types cannot be displayed directly in a browser but can be rendered.
Definition: SvgHandler.php:64
getScriptParams( $params)
Definition: SvgHandler.php:593
makeParamString( $params)
Definition: SvgHandler.php:557
getCommonMetaArray(File $file)
Get an array of standard (FormatMetadata type) metadata values.
Definition: SvgHandler.php:602
doTransform( $image, $dstPath, $dstUrl, $params, $flags=0)
Definition: SvgHandler.php:233
validateMetadata( $unser)
Definition: SvgHandler.php:453
getLanguageFromParams(array $params)
Determines render language from image parameters This is a lowercase IETF language.
Definition: SvgHandler.php:153
getAvailableLanguages(File $file)
Which languages (systemLanguage attribute) is supported.
Definition: SvgHandler.php:98
getLongDesc( $file)
Subtitle for the image.
Definition: SvgHandler.php:409
normaliseParamsInternal( $image, $params)
Code taken out of normaliseParams() for testability.
Definition: SvgHandler.php:199
getMetadataType( $image)
Get a string describing the type of metadata, for display purposes.
Definition: SvgHandler.php:461
getThumbType( $ext, $mime, $params=null)
Get the thumbnail extension and MIME type for a given source MIME type.
Definition: SvgHandler.php:396
getDefaultRenderLanguage(File $file)
What language to render file in if none selected.
Definition: SvgHandler.php:163
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:327
getSizeAndMetadata( $state, $filename)
Definition: SvgHandler.php:429
isEnabled()
False if the handler is disabled for all files.
Definition: SvgHandler.php:52
canAnimateThumbnail( $file)
We do not support making animated svg thumbnails.
Definition: SvgHandler.php:172
visibleMetadataFields()
Get a list of metadata items which should be displayed when the metadata table is collapsed.
Definition: SvgHandler.php:478
static rasterizeImagickExt( $srcPath, $dstPath, $width, $height)
Definition: SvgHandler.php:381
isFileMetadataValid( $image)
Check if the metadata is valid for this handler.
Definition: SvgHandler.php:465
isAnimatedImage( $file)
Definition: SvgHandler.php:76
getMatchedLanguage( $userPreferredLanguage, array $svgLanguages)
SVG's systemLanguage matching rules state: 'The systemLanguage attribute ...
Definition: SvgHandler.php:126
const SVG_METADATA_VERSION
Definition: SvgHandler.php:37
getParamMap()
Get an associative array mapping magic word IDs to parameter names.Will be used by the parser to iden...
Definition: SvgHandler.php:585
Media transform output for images.
Shortcut class for parameter validation errors.
$mime
Definition: router.php:60
if(PHP_SAPI !='cli-server') if(!isset( $_SERVER['SCRIPT_FILENAME'])) $file
Item class for a filearchive table row.
Definition: router.php:42
if(!is_readable( $file)) $ext
Definition: router.php:48
if(!isset( $args[0])) $lang