includes/resourceloader/ResourceLoaderImage.php

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