1decdbce53
Well, protected, because we want to have unit tests for them, apparently. Change-Id: I734b88599e5860aa59a07a89cc5389eb73b48813
490 lines
16 KiB
PHP
490 lines
16 KiB
PHP
<?php
|
|
/**
|
|
* Minification of CSS stylesheets.
|
|
*
|
|
* Copyright 2010 Wikimedia Foundation
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
* not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software distributed
|
|
* under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
|
|
* OF ANY KIND, either express or implied. See the License for the
|
|
* specific language governing permissions and limitations under the License.
|
|
*
|
|
* @file
|
|
* @version 0.1.1 -- 2010-09-11
|
|
* @author Trevor Parscal <tparscal@wikimedia.org>
|
|
* @copyright Copyright 2010 Wikimedia Foundation
|
|
* @license http://www.apache.org/licenses/LICENSE-2.0
|
|
*/
|
|
|
|
/**
|
|
* Transforms CSS data
|
|
*
|
|
* This class provides minification, URL remapping, URL extracting, and data-URL embedding.
|
|
*/
|
|
class CSSMin {
|
|
|
|
/* Constants */
|
|
|
|
/** @var string Strip marker for comments. **/
|
|
const PLACEHOLDER = "\x7fPLACEHOLDER\x7f";
|
|
|
|
/**
|
|
* Internet Explorer data URI length limit. See encodeImageAsDataURI().
|
|
*/
|
|
const DATA_URI_SIZE_LIMIT = 32768;
|
|
const URL_REGEX = 'url\(\s*[\'"]?(?P<file>[^\?\)\'"]*?)(?P<query>\?[^\)\'"]*?|)[\'"]?\s*\)';
|
|
const EMBED_REGEX = '\/\*\s*\@embed\s*\*\/';
|
|
const COMMENT_REGEX = '\/\*.*?\*\/';
|
|
|
|
/* Protected Static Members */
|
|
|
|
/** @var array List of common image files extensions and MIME-types */
|
|
protected static $mimeTypes = [
|
|
'gif' => 'image/gif',
|
|
'jpe' => 'image/jpeg',
|
|
'jpeg' => 'image/jpeg',
|
|
'jpg' => 'image/jpeg',
|
|
'png' => 'image/png',
|
|
'tif' => 'image/tiff',
|
|
'tiff' => 'image/tiff',
|
|
'xbm' => 'image/x-xbitmap',
|
|
'svg' => 'image/svg+xml',
|
|
];
|
|
|
|
/* Static Methods */
|
|
|
|
/**
|
|
* Gets a list of local file paths which are referenced in a CSS style sheet.
|
|
*
|
|
* If you wish non-existent files to be listed too, use getAllLocalFileReferences().
|
|
*
|
|
* For backwards-compatibility, if the second parameter is not given or null,
|
|
* this function will return an empty array instead of erroring out.
|
|
*
|
|
* @param string $source CSS stylesheet source to process
|
|
* @param string $path File path where the source was read from
|
|
* @return array List of local file references
|
|
*/
|
|
public static function getLocalFileReferences( $source, $path = null ) {
|
|
if ( $path === null ) {
|
|
return [];
|
|
}
|
|
|
|
$files = self::getAllLocalFileReferences( $source, $path );
|
|
|
|
// Skip non-existent files
|
|
$files = array_filter( $files, function ( $file ) {
|
|
return file_exists( $file );
|
|
} );
|
|
|
|
return $files;
|
|
}
|
|
|
|
/**
|
|
* Gets a list of local file paths which are referenced in a CSS style sheet, including
|
|
* non-existent files.
|
|
*
|
|
* @param string $source CSS stylesheet source to process
|
|
* @param string $path File path where the source was read from
|
|
* @return array List of local file references
|
|
*/
|
|
public static function getAllLocalFileReferences( $source, $path ) {
|
|
$stripped = preg_replace( '/' . self::COMMENT_REGEX . '/s', '', $source );
|
|
$path = rtrim( $path, '/' ) . '/';
|
|
$files = [];
|
|
|
|
$rFlags = PREG_OFFSET_CAPTURE | PREG_SET_ORDER;
|
|
if ( preg_match_all( '/' . self::URL_REGEX . '/', $stripped, $matches, $rFlags ) ) {
|
|
foreach ( $matches as $match ) {
|
|
$url = $match['file'][0];
|
|
|
|
// Skip fully-qualified and protocol-relative URLs and data URIs
|
|
if ( substr( $url, 0, 2 ) === '//' || parse_url( $url, PHP_URL_SCHEME ) ) {
|
|
break;
|
|
}
|
|
|
|
$files[] = $path . $url;
|
|
}
|
|
}
|
|
return $files;
|
|
}
|
|
|
|
/**
|
|
* Encode an image file as a data URI.
|
|
*
|
|
* If the image file has a suitable MIME type and size, encode it as a data URI, base64-encoded
|
|
* for binary files or just percent-encoded otherwise. Return false if the image type is
|
|
* unfamiliar or file exceeds the size limit.
|
|
*
|
|
* @param string $file Image file to encode.
|
|
* @param string|null $type File's MIME type or null. If null, CSSMin will
|
|
* try to autodetect the type.
|
|
* @param bool $ie8Compat By default, a data URI will only be produced if it can be made short
|
|
* enough to fit in Internet Explorer 8 (and earlier) URI length limit (32,768 bytes). Pass
|
|
* `false` to remove this limitation.
|
|
* @return string|bool Image contents encoded as a data URI or false.
|
|
*/
|
|
public static function encodeImageAsDataURI( $file, $type = null, $ie8Compat = true ) {
|
|
// Fast-fail for files that definitely exceed the maximum data URI length
|
|
if ( $ie8Compat && filesize( $file ) >= self::DATA_URI_SIZE_LIMIT ) {
|
|
return false;
|
|
}
|
|
|
|
if ( $type === null ) {
|
|
$type = self::getMimeType( $file );
|
|
}
|
|
if ( !$type ) {
|
|
return false;
|
|
}
|
|
|
|
return self::encodeStringAsDataURI( file_get_contents( $file ), $type, $ie8Compat );
|
|
}
|
|
|
|
/**
|
|
* Encode file contents as a data URI with chosen MIME type.
|
|
*
|
|
* The URI will be base64-encoded for binary files or just percent-encoded otherwise.
|
|
*
|
|
* @since 1.25
|
|
*
|
|
* @param string $contents File contents to encode.
|
|
* @param string $type File's MIME type.
|
|
* @param bool $ie8Compat See encodeImageAsDataURI().
|
|
* @return string|bool Image contents encoded as a data URI or false.
|
|
*/
|
|
public static function encodeStringAsDataURI( $contents, $type, $ie8Compat = true ) {
|
|
// Try #1: Non-encoded data URI
|
|
// The regular expression matches ASCII whitespace and printable characters.
|
|
if ( preg_match( '/^[\r\n\t\x20-\x7e]+$/', $contents ) ) {
|
|
// Do not base64-encode non-binary files (sane SVGs).
|
|
// (This often produces longer URLs, but they compress better, yielding a net smaller size.)
|
|
$uri = 'data:' . $type . ',' . rawurlencode( $contents );
|
|
if ( !$ie8Compat || strlen( $uri ) < self::DATA_URI_SIZE_LIMIT ) {
|
|
return $uri;
|
|
}
|
|
}
|
|
|
|
// Try #2: Encoded data URI
|
|
$uri = 'data:' . $type . ';base64,' . base64_encode( $contents );
|
|
if ( !$ie8Compat || strlen( $uri ) < self::DATA_URI_SIZE_LIMIT ) {
|
|
return $uri;
|
|
}
|
|
|
|
// A data URI couldn't be produced
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Serialize a string (escape and quote) for use as a CSS string value.
|
|
* http://www.w3.org/TR/2013/WD-cssom-20131205/#serialize-a-string
|
|
*
|
|
* @param string $value
|
|
* @return string
|
|
* @throws Exception
|
|
*/
|
|
public static function serializeStringValue( $value ) {
|
|
if ( strstr( $value, "\0" ) ) {
|
|
throw new Exception( "Invalid character in CSS string" );
|
|
}
|
|
$value = strtr( $value, [ '\\' => '\\\\', '"' => '\\"' ] );
|
|
$value = preg_replace_callback( '/[\x01-\x1f\x7f-\x9f]/', function ( $match ) {
|
|
return '\\' . base_convert( ord( $match[0] ), 10, 16 ) . ' ';
|
|
}, $value );
|
|
return '"' . $value . '"';
|
|
}
|
|
|
|
/**
|
|
* @param $file string
|
|
* @return bool|string
|
|
*/
|
|
public static function getMimeType( $file ) {
|
|
$realpath = realpath( $file );
|
|
if (
|
|
$realpath
|
|
&& function_exists( 'finfo_file' )
|
|
&& function_exists( 'finfo_open' )
|
|
&& defined( 'FILEINFO_MIME_TYPE' )
|
|
) {
|
|
return finfo_file( finfo_open( FILEINFO_MIME_TYPE ), $realpath );
|
|
}
|
|
|
|
// Infer the MIME-type from the file extension
|
|
$ext = strtolower( pathinfo( $file, PATHINFO_EXTENSION ) );
|
|
if ( isset( self::$mimeTypes[$ext] ) ) {
|
|
return self::$mimeTypes[$ext];
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Build a CSS 'url()' value for the given URL, quoting parentheses (and other funny characters)
|
|
* and escaping quotes as necessary.
|
|
*
|
|
* See http://www.w3.org/TR/css-syntax-3/#consume-a-url-token
|
|
*
|
|
* @param string $url URL to process
|
|
* @return string 'url()' value, usually just `"url($url)"`, quoted/escaped if necessary
|
|
*/
|
|
public static function buildUrlValue( $url ) {
|
|
// The list below has been crafted to match URLs such as:
|
|
// scheme://user@domain:port/~user/fi%20le.png?query=yes&really=y+s
|
|
// data:image/png;base64,R0lGODlh/+==
|
|
if ( preg_match( '!^[\w\d:@/~.%+;,?&=-]+$!', $url ) ) {
|
|
return "url($url)";
|
|
} else {
|
|
return 'url("' . strtr( $url, [ '\\' => '\\\\', '"' => '\\"' ] ) . '")';
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Remaps CSS URL paths and automatically embeds data URIs for CSS rules
|
|
* or url() values preceded by an / * @embed * / comment.
|
|
*
|
|
* @param string $source CSS data to remap
|
|
* @param string $local File path where the source was read from
|
|
* @param string $remote URL path to the file
|
|
* @param bool $embedData If false, never do any data URI embedding,
|
|
* even if / * @embed * / is found.
|
|
* @return string Remapped CSS data
|
|
*/
|
|
public static function remap( $source, $local, $remote, $embedData = true ) {
|
|
// High-level overview:
|
|
// * For each CSS rule in $source that includes at least one url() value:
|
|
// * Check for an @embed comment at the start indicating that all URIs should be embedded
|
|
// * For each url() value:
|
|
// * Check for an @embed comment directly preceding the value
|
|
// * If either @embed comment exists:
|
|
// * Embedding the URL as data: URI, if it's possible / allowed
|
|
// * Otherwise remap the URL to work in generated stylesheets
|
|
|
|
// Guard against trailing slashes, because "some/remote/../foo.png"
|
|
// resolves to "some/remote/foo.png" on (some?) clients (bug 27052).
|
|
if ( substr( $remote, -1 ) == '/' ) {
|
|
$remote = substr( $remote, 0, -1 );
|
|
}
|
|
|
|
// Disallow U+007F DELETE, which is illegal anyway, and which
|
|
// we use for comment placeholders.
|
|
$source = str_replace( "\x7f", "?", $source );
|
|
|
|
// Replace all comments by a placeholder so they will not interfere with the remapping.
|
|
// Warning: This will also catch on anything looking like the start of a comment between
|
|
// quotation marks (e.g. "foo /* bar").
|
|
$comments = [];
|
|
|
|
$pattern = '/(?!' . CSSMin::EMBED_REGEX . ')(' . CSSMin::COMMENT_REGEX . ')/s';
|
|
|
|
$source = preg_replace_callback(
|
|
$pattern,
|
|
function ( $match ) use ( &$comments ) {
|
|
$comments[] = $match[ 0 ];
|
|
return CSSMin::PLACEHOLDER . ( count( $comments ) - 1 ) . 'x';
|
|
},
|
|
$source
|
|
);
|
|
|
|
// Note: This will not correctly handle cases where ';', '{' or '}'
|
|
// appears in the rule itself, e.g. in a quoted string. You are advised
|
|
// not to use such characters in file names. We also match start/end of
|
|
// the string to be consistent in edge-cases ('@import url(…)').
|
|
$pattern = '/(?:^|[;{])\K[^;{}]*' . CSSMin::URL_REGEX . '[^;}]*(?=[;}]|$)/';
|
|
|
|
$source = preg_replace_callback(
|
|
$pattern,
|
|
function ( $matchOuter ) use ( $local, $remote, $embedData ) {
|
|
$rule = $matchOuter[0];
|
|
|
|
// Check for global @embed comment and remove it. Allow other comments to be present
|
|
// before @embed (they have been replaced with placeholders at this point).
|
|
$embedAll = false;
|
|
$rule = preg_replace(
|
|
'/^((?:\s+|' .
|
|
CSSMin::PLACEHOLDER .
|
|
'(\d+)x)*)' .
|
|
CSSMin::EMBED_REGEX .
|
|
'\s*/',
|
|
'$1',
|
|
$rule,
|
|
1,
|
|
$embedAll
|
|
);
|
|
|
|
// Build two versions of current rule: with remapped URLs
|
|
// and with embedded data: URIs (where possible).
|
|
$pattern = '/(?P<embed>' . CSSMin::EMBED_REGEX . '\s*|)' . CSSMin::URL_REGEX . '/';
|
|
|
|
$ruleWithRemapped = preg_replace_callback(
|
|
$pattern,
|
|
function ( $match ) use ( $local, $remote ) {
|
|
$remapped = CSSMin::remapOne( $match['file'], $match['query'], $local, $remote, false );
|
|
|
|
return CSSMin::buildUrlValue( $remapped );
|
|
},
|
|
$rule
|
|
);
|
|
|
|
if ( $embedData ) {
|
|
// Remember the occurring MIME types to avoid fallbacks when embedding some files.
|
|
$mimeTypes = [];
|
|
|
|
$ruleWithEmbedded = preg_replace_callback(
|
|
$pattern,
|
|
function ( $match ) use ( $embedAll, $local, $remote, &$mimeTypes ) {
|
|
$embed = $embedAll || $match['embed'];
|
|
$embedded = CSSMin::remapOne(
|
|
$match['file'],
|
|
$match['query'],
|
|
$local,
|
|
$remote,
|
|
$embed
|
|
);
|
|
|
|
$url = $match['file'] . $match['query'];
|
|
$file = $local . $match['file'];
|
|
if (
|
|
!self::isRemoteUrl( $url ) && !self::isLocalUrl( $url )
|
|
&& file_exists( $file )
|
|
) {
|
|
$mimeTypes[ CSSMin::getMimeType( $file ) ] = true;
|
|
}
|
|
|
|
return CSSMin::buildUrlValue( $embedded );
|
|
},
|
|
$rule
|
|
);
|
|
|
|
// Are all referenced images SVGs?
|
|
$needsEmbedFallback = $mimeTypes !== [ 'image/svg+xml' => true ];
|
|
}
|
|
|
|
if ( !$embedData || $ruleWithEmbedded === $ruleWithRemapped ) {
|
|
// We're not embedding anything, or we tried to but the file is not embeddable
|
|
return $ruleWithRemapped;
|
|
} elseif ( $embedData && $needsEmbedFallback ) {
|
|
// Build 2 CSS properties; one which uses a data URI in place of the @embed comment, and
|
|
// the other with a remapped and versioned URL with an Internet Explorer 6 and 7 hack
|
|
// making it ignored in all browsers that support data URIs
|
|
return "$ruleWithEmbedded;$ruleWithRemapped!ie";
|
|
} else {
|
|
// Look ma, no fallbacks! This is for files which IE 6 and 7 don't support anyway: SVG.
|
|
return $ruleWithEmbedded;
|
|
}
|
|
}, $source );
|
|
|
|
// Re-insert comments
|
|
$pattern = '/' . CSSMin::PLACEHOLDER . '(\d+)x/';
|
|
$source = preg_replace_callback( $pattern, function( $match ) use ( &$comments ) {
|
|
return $comments[ $match[1] ];
|
|
}, $source );
|
|
|
|
return $source;
|
|
|
|
}
|
|
|
|
/**
|
|
* Is this CSS rule referencing a remote URL?
|
|
*
|
|
* @param string $maybeUrl
|
|
* @return bool
|
|
*/
|
|
protected static function isRemoteUrl( $maybeUrl ) {
|
|
if ( substr( $maybeUrl, 0, 2 ) === '//' || parse_url( $maybeUrl, PHP_URL_SCHEME ) ) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Is this CSS rule referencing a local URL?
|
|
*
|
|
* @param string $maybeUrl
|
|
* @return bool
|
|
*/
|
|
protected static function isLocalUrl( $maybeUrl ) {
|
|
if ( $maybeUrl !== '' && $maybeUrl[0] === '/' && !self::isRemoteUrl( $maybeUrl ) ) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Remap or embed a CSS URL path.
|
|
*
|
|
* @param string $file URL to remap/embed
|
|
* @param string $query
|
|
* @param string $local File path where the source was read from
|
|
* @param string $remote URL path to the file
|
|
* @param bool $embed Whether to do any data URI embedding
|
|
* @return string Remapped/embedded URL data
|
|
*/
|
|
public static function remapOne( $file, $query, $local, $remote, $embed ) {
|
|
// The full URL possibly with query, as passed to the 'url()' value in CSS
|
|
$url = $file . $query;
|
|
|
|
// Expand local URLs with absolute paths like /w/index.php to possibly protocol-relative URL, if
|
|
// wfExpandUrl() is available. (This will not be the case if we're running outside of MW.)
|
|
if ( self::isLocalUrl( $url ) && function_exists( 'wfExpandUrl' ) ) {
|
|
return wfExpandUrl( $url, PROTO_RELATIVE );
|
|
}
|
|
|
|
// Pass thru fully-qualified and protocol-relative URLs and data URIs, as well as local URLs if
|
|
// we can't expand them.
|
|
if ( self::isRemoteUrl( $url ) || self::isLocalUrl( $url ) ) {
|
|
return $url;
|
|
}
|
|
|
|
if ( $local === false ) {
|
|
// Assume that all paths are relative to $remote, and make them absolute
|
|
$url = $remote . '/' . $url;
|
|
} else {
|
|
// We drop the query part here and instead make the path relative to $remote
|
|
$url = "{$remote}/{$file}";
|
|
// Path to the actual file on the filesystem
|
|
$localFile = "{$local}/{$file}";
|
|
if ( file_exists( $localFile ) ) {
|
|
if ( $embed ) {
|
|
$data = self::encodeImageAsDataURI( $localFile );
|
|
if ( $data !== false ) {
|
|
return $data;
|
|
}
|
|
}
|
|
if ( method_exists( 'OutputPage', 'transformFilePath' ) ) {
|
|
$url = OutputPage::transformFilePath( $remote, $local, $file );
|
|
} else {
|
|
// Add version parameter as the first five hex digits
|
|
// of the MD5 hash of the file's contents.
|
|
$url .= '?' . substr( md5_file( $localFile ), 0, 5 );
|
|
}
|
|
}
|
|
// If any of these conditions failed (file missing, we don't want to embed it
|
|
// or it's not embeddable), return the URL (possibly with ?timestamp part)
|
|
}
|
|
if ( function_exists( 'wfRemoveDotSegments' ) ) {
|
|
$url = wfRemoveDotSegments( $url );
|
|
}
|
|
return $url;
|
|
}
|
|
|
|
/**
|
|
* Removes whitespace from CSS data
|
|
*
|
|
* @param string $css CSS data to minify
|
|
* @return string Minified CSS data
|
|
*/
|
|
public static function minify( $css ) {
|
|
return trim(
|
|
str_replace(
|
|
[ '; ', ': ', ' {', '{ ', ', ', '} ', ';}' ],
|
|
[ ';', ':', '{', '{', ',', '}', '}' ],
|
|
preg_replace( [ '/\s+/', '/\/\*.*?\*\//s' ], [ ' ', '' ], $css )
|
|
)
|
|
);
|
|
}
|
|
}
|