includes/resourceloader/ResourceLoaderImage.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  */
  20
  21 use MediaWiki\Shell\Shell;
  22
  23 /**
  24  * Class encapsulating an image used in a ResourceLoaderImageModule.
  25  *
  26  * @ingroup ResourceLoader
  27  * @since 1.25
  28  */
  29 class ResourceLoaderImage {
  30
  31         /**
  32          * Map of allowed file extensions to their MIME types.
  33          * @var array
  34          */
  35         protected static $fileTypes = [
  36                 'svg' => 'image/svg+xml',
  37                 'png' => 'image/png',
  38                 'gif' => 'image/gif',
  39                 'jpg' => 'image/jpg',
  40         ];
  41
  42         /** @var string */
  43         private $name;
  44         /** @var string */
  45         private $module;
  46         /** @var string|array */
  47         private $descriptor;
  48         /** @var string */
  49         private $basePath;
  50         /** @var array */
  51         private $variants;
  52         /** @var string|null */
  53         private $defaultColor;
  54         /** @var string */
  55         private $extension;
  56
  57         /**
  58          * @param string $name Image name
  59          * @param string $module Module name
  60          * @param string|array $descriptor Path to image file, or array structure containing paths
  61          * @param string $basePath Directory to which paths in descriptor refer
  62          * @param array $variants
  63          * @param string|null $defaultColor of the base variant
  64          * @throws InvalidArgumentException
  65          */
  66         public function __construct( $name, $module, $descriptor, $basePath, $variants,
  67                 $defaultColor = null
  68         ) {
  69                 $this->name = $name;
  70                 $this->module = $module;
  71                 $this->descriptor = $descriptor;
  72                 $this->basePath = $basePath;
  73                 $this->variants = $variants;
  74                 $this->defaultColor = $defaultColor;
  75
  76                 // Expand shorthands:
  77                 // [ "en,de,fr" => "foo.svg" ]
  78                 // → [ "en" => "foo.svg", "de" => "foo.svg", "fr" => "foo.svg" ]
  79                 if ( is_array( $this->descriptor ) && isset( $this->descriptor['lang'] ) ) {
  80                         foreach ( array_keys( $this->descriptor['lang'] ) as $langList ) {
  81                                 if ( strpos( $langList, ',' ) !== false ) {
  82                                         $this->descriptor['lang'] += array_fill_keys(
  83                                                 explode( ',', $langList ),
  84                                                 $this->descriptor['lang'][$langList]
  85                                         );
  86                                         unset( $this->descriptor['lang'][$langList] );
  87                                 }
  88                         }
  89                 }
  90                 // Remove 'deprecated' key
  91                 if ( is_array( $this->descriptor ) ) {
  92                         unset( $this->descriptor['deprecated'] );
  93                 }
  94
  95                 // Ensure that all files have common extension.
  96                 $extensions = [];
  97                 $descriptor = is_array( $this->descriptor ) ? $this->descriptor : [ $this->descriptor ];
  98                 array_walk_recursive( $descriptor, function ( $path ) use ( &$extensions ) {
  99                         $extensions[] = pathinfo( $this->getLocalPath( $path ), PATHINFO_EXTENSION );
 100                 } );
 101                 $extensions = array_unique( $extensions );
 102                 if ( count( $extensions ) !== 1 ) {
 103                         throw new InvalidArgumentException(
 104                                 "File type for different image files of '$name' not the same in module '$module'"
 105                         );
 106                 }
 107                 $ext = $extensions[0];
 108                 if ( !isset( self::$fileTypes[$ext] ) ) {
 109                         throw new InvalidArgumentException(
 110                                 "Invalid file type for image files of '$name' (valid: svg, png, gif, jpg) in module '$module'"
 111                         );
 112                 }
 113                 $this->extension = $ext;
 114         }
 115
 116         /**
 117          * Get name of this image.
 118          *
 119          * @return string
 120          */
 121         public function getName() {
 122                 return $this->name;
 123         }
 124
 125         /**
 126          * Get name of the module this image belongs to.
 127          *
 128          * @return string
 129          */
 130         public function getModule() {
 131                 return $this->module;
 132         }
 133
 134         /**
 135          * Get the list of variants this image can be converted to.
 136          *
 137          * @return string[]
 138          */
 139         public function getVariants() {
 140                 return array_keys( $this->variants );
 141         }
 142
 143         /**
 144          * Get the path to image file for given context.
 145          *
 146          * @param ResourceLoaderContext $context Any context
 147          * @return string
 148          * @throws MWException If no matching path is found
 149          */
 150         public function getPath( ResourceLoaderContext $context ) {
 151                 $desc = $this->descriptor;
 152                 if ( !is_array( $desc ) ) {
 153                         return $this->getLocalPath( $desc );
 154                 }
 155                 if ( isset( $desc['lang'] ) ) {
 156                         $contextLang = $context->getLanguage();
 157                         if ( isset( $desc['lang'][$contextLang] ) ) {
 158                                 return $this->getLocalPath( $desc['lang'][$contextLang] );
 159                         }
 160                         $fallbacks = Language::getFallbacksFor( $contextLang, Language::STRICT_FALLBACKS );
 161                         foreach ( $fallbacks as $lang ) {
 162                                 if ( isset( $desc['lang'][$lang] ) ) {
 163                                         return $this->getLocalPath( $desc['lang'][$lang] );
 164                                 }
 165                         }
 166                 }
 167                 if ( isset( $desc[$context->getDirection()] ) ) {
 168                         return $this->getLocalPath( $desc[$context->getDirection()] );
 169                 }
 170                 if ( isset( $desc['default'] ) ) {
 171                         return $this->getLocalPath( $desc['default'] );
 172                 } else {
 173                         throw new MWException( 'No matching path found' );
 174                 }
 175         }
 176
 177         /**
 178          * @param string|ResourceLoaderFilePath $path
 179          * @return string
 180          */
 181         protected function getLocalPath( $path ) {
 182                 if ( $path instanceof ResourceLoaderFilePath ) {
 183                         return $path->getLocalPath();
 184                 }
 185
 186                 return "{$this->basePath}/$path";
 187         }
 188
 189         /**
 190          * Get the extension of the image.
 191          *
 192          * @param string $format Format to get the extension for, 'original' or 'rasterized'
 193          * @return string Extension without leading dot, e.g. 'png'
 194          */
 195         public function getExtension( $format = 'original' ) {
 196                 if ( $format === 'rasterized' && $this->extension === 'svg' ) {
 197                         return 'png';
 198                 }
 199                 return $this->extension;
 200         }
 201
 202         /**
 203          * Get the MIME type of the image.
 204          *
 205          * @param string $format Format to get the MIME type for, 'original' or 'rasterized'
 206          * @return string
 207          */
 208         public function getMimeType( $format = 'original' ) {
 209                 $ext = $this->getExtension( $format );
 210                 return self::$fileTypes[$ext];
 211         }
 212
 213         /**
 214          * Get the load.php URL that will produce this image.
 215          *
 216          * @param ResourceLoaderContext $context Any context
 217          * @param string $script URL to load.php
 218          * @param string|null $variant Variant to get the URL for
 219          * @param string $format Format to get the URL for, 'original' or 'rasterized'
 220          * @return string
 221          */
 222         public function getUrl( ResourceLoaderContext $context, $script, $variant, $format ) {
 223                 $query = [
 224                         'modules' => $this->getModule(),
 225                         'image' => $this->getName(),
 226                         'variant' => $variant,
 227                         'format' => $format,
 228                 ];
 229                 if ( $this->varyOnLanguage() ) {
 230                         $query['lang'] = $context->getLanguage();
 231                 }
 232                 // The following parameters are at the end to keep the original order of the parameters.
 233                 $query['skin'] = $context->getSkin();
 234                 $query['version'] = $context->getVersion();
 235
 236                 return wfAppendQuery( $script, $query );
 237         }
 238
 239         /**
 240          * Get the data: URI that will produce this image.
 241          *
 242          * @param ResourceLoaderContext $context Any context
 243          * @param string|null $variant Variant to get the URI for
 244          * @param string $format Format to get the URI for, 'original' or 'rasterized'
 245          * @return string
 246          */
 247         public function getDataUri( ResourceLoaderContext $context, $variant, $format ) {
 248                 $type = $this->getMimeType( $format );
 249                 $contents = $this->getImageData( $context, $variant, $format );
 250                 return CSSMin::encodeStringAsDataURI( $contents, $type );
 251         }
 252
 253         /**
 254          * Get actual image data for this image. This can be saved to a file or sent to the browser to
 255          * produce the converted image.
 256          *
 257          * Call getExtension() or getMimeType() with the same $format argument to learn what file type the
 258          * returned data uses.
 259          *
 260          * @param ResourceLoaderContext $context Image context, or any context if $variant and $format
 261          *     given.
 262          * @param string|null $variant Variant to get the data for. Optional; if given, overrides the data
 263          *     from $context.
 264          * @param string $format Format to get the data for, 'original' or 'rasterized'. Optional; if
 265          *     given, overrides the data from $context.
 266          * @return string|false Possibly binary image data, or false on failure
 267          * @throws MWException If the image file doesn't exist
 268          */
 269         public function getImageData( ResourceLoaderContext $context, $variant = false, $format = false ) {
 270                 if ( $variant === false ) {
 271                         $variant = $context->getVariant();
 272                 }
 273                 if ( $format === false ) {
 274                         $format = $context->getFormat();
 275                 }
 276
 277                 $path = $this->getPath( $context );
 278                 if ( !file_exists( $path ) ) {
 279                         throw new MWException( "File '$path' does not exist" );
 280                 }
 281
 282                 if ( $this->getExtension() !== 'svg' ) {
 283                         return file_get_contents( $path );
 284                 }
 285
 286                 if ( $variant && isset( $this->variants[$variant] ) ) {
 287                         $data = $this->variantize( $this->variants[$variant], $context );
 288                 } else {
 289                         $defaultColor = $this->defaultColor;
 290                         $data = $defaultColor ?
 291                                 $this->variantize( [ 'color' => $defaultColor ], $context ) :
 292                                 file_get_contents( $path );
 293                 }
 294
 295                 if ( $format === 'rasterized' ) {
 296                         $data = $this->rasterize( $data );
 297                         if ( !$data ) {
 298                                 wfDebugLog( 'ResourceLoaderImage', __METHOD__ . " failed to rasterize for $path" );
 299                         }
 300                 }
 301
 302                 return $data;
 303         }
 304
 305         /**
 306          * Send response headers (using the header() function) that are necessary to correctly serve the
 307          * image data for this image, as returned by getImageData().
 308          *
 309          * Note that the headers are independent of the language or image variant.
 310          *
 311          * @param ResourceLoaderContext $context Image context
 312          */
 313         public function sendResponseHeaders( ResourceLoaderContext $context ) {
 314                 $format = $context->getFormat();
 315                 $mime = $this->getMimeType( $format );
 316                 $filename = $this->getName() . '.' . $this->getExtension( $format );
 317
 318                 header( 'Content-Type: ' . $mime );
 319                 header( 'Content-Disposition: ' .
 320                         FileBackend::makeContentDisposition( 'inline', $filename ) );
 321         }
 322
 323         /**
 324          * Convert this image, which is assumed to be SVG, to given variant.
 325          *
 326          * @param array $variantConf Array with a 'color' key, its value will be used as fill color
 327          * @param ResourceLoaderContext $context Image context
 328          * @return string New SVG file data
 329          */
 330         protected function variantize( $variantConf, ResourceLoaderContext $context ) {
 331                 $dom = new DOMDocument;
 332                 $dom->loadXML( file_get_contents( $this->getPath( $context ) ) );
 333                 $root = $dom->documentElement;
 334                 $titleNode = null;
 335                 $wrapper = $dom->createElementNS( 'http://www.w3.org/2000/svg', 'g' );
 336                 // Reattach all direct children of the `<svg>` root node to the `<g>` wrapper
 337                 while ( $root->firstChild ) {
 338                         $node = $root->firstChild;
 339                         // @phan-suppress-next-line PhanUndeclaredProperty False positive
 340                         if ( !$titleNode && $node->nodeType === XML_ELEMENT_NODE && $node->tagName === 'title' ) {
 341                                 // Remember the first encountered `<title>` node
 342                                 $titleNode = $node;
 343                         }
 344                         $wrapper->appendChild( $node );
 345                 }
 346                 if ( $titleNode ) {
 347                         // Reattach the `<title>` node to the `<svg>` root node rather than the `<g>` wrapper
 348                         $root->appendChild( $titleNode );
 349                 }
 350                 $root->appendChild( $wrapper );
 351                 $wrapper->setAttribute( 'fill', $variantConf['color'] );
 352                 return $dom->saveXML();
 353         }
 354
 355         /**
 356          * Massage the SVG image data for converters which don't understand some path data syntax.
 357          *
 358          * This is necessary for rsvg and ImageMagick when compiled with rsvg support.
 359          * Upstream bug is https://bugzilla.gnome.org/show_bug.cgi?id=620923, fixed 2014-11-10, so
 360          * this will be needed for a while. (T76852)
 361          *
 362          * @param string $svg SVG image data
 363          * @return string Massaged SVG image data
 364          */
 365         protected function massageSvgPathdata( $svg ) {
 366                 $dom = new DOMDocument;
 367                 $dom->loadXML( $svg );
 368                 foreach ( $dom->getElementsByTagName( 'path' ) as $node ) {
 369                         $pathData = $node->getAttribute( 'd' );
 370                         // Make sure there is at least one space between numbers, and that leading zero is not omitted.
 371                         // rsvg has issues with syntax like "M-1-2" and "M.445.483" and especially "M-.445-.483".
 372                         $pathData = preg_replace( '/(-?)(\d*\.\d+|\d+)/', ' ${1}0$2 ', $pathData );
 373                         // Strip unnecessary leading zeroes for prettiness, not strictly necessary
 374                         $pathData = preg_replace( '/([ -])0(\d)/', '$1$2', $pathData );
 375                         $node->setAttribute( 'd', $pathData );
 376                 }
 377                 return $dom->saveXML();
 378         }
 379
 380         /**
 381          * Convert passed image data, which is assumed to be SVG, to PNG.
 382          *
 383          * @param string $svg SVG image data
 384          * @return string|bool PNG image data, or false on failure
 385          */
 386         protected function rasterize( $svg ) {
 387                 /**
 388                  * This code should be factored out to a separate method on SvgHandler, or perhaps a separate
 389                  * class, with a separate set of configuration settings.
 390                  *
 391                  * This is a distinct use case from regular SVG rasterization:
 392                  * * We can skip many sanity and security checks (as the images come from a trusted source,
 393                  *   rather than from the user).
 394                  * * We need to provide extra options to some converters to achieve acceptable quality for very
 395                  *   small images, which might cause performance issues in the general case.
 396                  * * We want to directly pass image data to the converter, rather than a file path.
 397                  *
 398                  * See https://phabricator.wikimedia.org/T76473#801446 for examples of what happens with the
 399                  * default settings.
 400                  *
 401                  * For now, we special-case rsvg (used in WMF production) and do a messy workaround for other
 402                  * converters.
 403                  */
 404
 405                 global $wgSVGConverter, $wgSVGConverterPath;
 406
 407                 $svg = $this->massageSvgPathdata( $svg );
 408
 409                 // Sometimes this might be 'rsvg-secure'. Long as it's rsvg.
 410                 if ( strpos( $wgSVGConverter, 'rsvg' ) === 0 ) {
 411                         $command = 'rsvg-convert';
 412                         if ( $wgSVGConverterPath ) {
 413                                 $command = Shell::escape( "$wgSVGConverterPath/" ) . $command;
 414                         }
 415
 416                         $process = proc_open(
 417                                 $command,
 418                                 [ 0 => [ 'pipe', 'r' ], 1 => [ 'pipe', 'w' ] ],
 419                                 $pipes
 420                         );
 421
 422                         if ( is_resource( $process ) ) {
 423                                 fwrite( $pipes[0], $svg );
 424                                 fclose( $pipes[0] );
 425                                 $png = stream_get_contents( $pipes[1] );
 426                                 fclose( $pipes[1] );
 427                                 proc_close( $process );
 428
 429                                 return $png ?: false;
 430                         }
 431                         return false;
 432
 433                 } else {
 434                         // Write input to and read output from a temporary file
 435                         $tempFilenameSvg = tempnam( wfTempDir(), 'ResourceLoaderImage' );
 436                         $tempFilenamePng = tempnam( wfTempDir(), 'ResourceLoaderImage' );
 437
 438                         file_put_contents( $tempFilenameSvg, $svg );
 439
 440                         $svgReader = new SVGReader( $tempFilenameSvg );
 441                         $metadata = $svgReader->getMetadata();
 442                         if ( !isset( $metadata['width'] ) || !isset( $metadata['height'] ) ) {
 443                                 unlink( $tempFilenameSvg );
 444                                 return false;
 445                         }
 446
 447                         $handler = new SvgHandler;
 448                         $res = $handler->rasterize(
 449                                 $tempFilenameSvg,
 450                                 $tempFilenamePng,
 451                                 $metadata['width'],
 452                                 $metadata['height']
 453                         );
 454                         unlink( $tempFilenameSvg );
 455
 456                         $png = null;
 457                         if ( $res === true ) {
 458                                 $png = file_get_contents( $tempFilenamePng );
 459                                 unlink( $tempFilenamePng );
 460                         }
 461
 462                         return $png ?: false;
 463                 }
 464         }
 465
 466         /**
 467          * Check if the image depends on the language.
 468          *
 469          * @return bool
 470          */
 471         private function varyOnLanguage() {
 472                 return is_array( $this->descriptor ) && (
 473                         isset( $this->descriptor['ltr'] ) ||
 474                         isset( $this->descriptor['rtl'] ) ||
 475                         isset( $this->descriptor['lang'] ) );
 476         }
 477 }