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