mediawiki-extensions-Syntax.../includes/SyntaxHighlight.php
Timo Tijhof 8c3a3ffda0 Update highlight() to use getWithSetCallback() idiom
* Use backend-specific makeGlobalKey() method instead of
  deprecated wfGlobalCacheKey().

* Call makeCacheKey() inline and reduce to only producing
  part of the key (makeCacheKeyHash).

* Add a $ttl (1 month), instead of the previously unspecified
  expiry (default: indefinite).

Change-Id: I913a768a3b61cc31ce14fa086a563ceecca7c603
2018-02-22 23:53:56 +00:00

577 lines
17 KiB
PHP

<?php
/**
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*/
use MediaWiki\Shell\Shell;
class SyntaxHighlight {
/** @var int The maximum number of lines that may be selected for highlighting. **/
const HIGHLIGHT_MAX_LINES = 1000;
/** @var int Maximum input size for the highlighter (100 kB). **/
const HIGHLIGHT_MAX_BYTES = 102400;
/** @var string CSS class for syntax-highlighted code. **/
const HIGHLIGHT_CSS_CLASS = 'mw-highlight';
/** @var int Cache version. Increment whenever the HTML changes. */
const CACHE_VERSION = 2;
/** @var array Mapping of MIME-types to lexer names. **/
private static $mimeLexers = [
'text/javascript' => 'javascript',
'application/json' => 'javascript',
'text/xml' => 'xml',
];
/**
* Get the Pygments lexer name for a particular language.
*
* @param string $lang Language name.
* @return string|null Lexer name, or null if no matching lexer.
*/
private static function getLexer( $lang ) {
static $lexers = null;
if ( $lang === null ) {
return null;
}
if ( !$lexers ) {
$lexers = require __DIR__ . '/../SyntaxHighlight.lexers.php';
}
$lexer = strtolower( $lang );
if ( in_array( $lexer, $lexers ) ) {
return $lexer;
}
$geshi2pygments = SyntaxHighlightGeSHiCompat::getGeSHiToPygmentsMap();
// Check if this is a GeSHi lexer name for which there exists
// a compatible Pygments lexer with a different name.
if ( isset( $geshi2pygments[$lexer] ) ) {
$lexer = $geshi2pygments[$lexer];
if ( in_array( $lexer, $lexers ) ) {
return $lexer;
}
}
return null;
}
/**
* Register parser hook
*
* @param Parser &$parser
*/
public static function onParserFirstCallInit( Parser &$parser ) {
foreach ( [ 'source', 'syntaxhighlight' ] as $tag ) {
$parser->setHook( $tag, [ 'SyntaxHighlight', 'parserHook' ] );
}
}
/**
* Parser hook
*
* @param string $text
* @param array $args
* @param Parser $parser
* @return string
* @throws MWException
*/
public static function parserHook( $text, $args, $parser ) {
global $wgUseTidy;
// Replace strip markers (For e.g. {{#tag:syntaxhighlight|<nowiki>...}})
$out = $parser->mStripState->unstripNoWiki( $text );
// Don't trim leading spaces away, just the linefeeds
$out = preg_replace( '/^\n+/', '', rtrim( $out ) );
// Convert deprecated attributes
if ( isset( $args['enclose'] ) ) {
if ( $args['enclose'] === 'none' ) {
$args['inline'] = true;
}
unset( $args['enclose'] );
}
$lexer = isset( $args['lang'] ) ? $args['lang'] : '';
$result = self::highlight( $out, $lexer, $args );
if ( !$result->isGood() ) {
$parser->addTrackingCategory( 'syntaxhighlight-error-category' );
}
$out = $result->getValue();
// HTML Tidy will convert tabs to spaces incorrectly (bug 30930).
// But the conversion from tab to space occurs while reading the input,
// before the conversion from &#9; to tab, so we can armor it that way.
if ( $wgUseTidy ) {
$out = str_replace( "\t", '&#9;', $out );
}
// Allow certain HTML attributes
$htmlAttribs = Sanitizer::validateAttributes( $args, [ 'style', 'class', 'id', 'dir' ] );
if ( !isset( $htmlAttribs['class'] ) ) {
$htmlAttribs['class'] = self::HIGHLIGHT_CSS_CLASS;
} else {
$htmlAttribs['class'] .= ' ' . self::HIGHLIGHT_CSS_CLASS;
}
if ( !( isset( $htmlAttribs['dir'] ) && $htmlAttribs['dir'] === 'rtl' ) ) {
$htmlAttribs['dir'] = 'ltr';
}
if ( isset( $args['inline'] ) ) {
// Enforce inlineness. Stray newlines may result in unexpected list and paragraph processing
// (also known as doBlockLevels()).
$out = str_replace( "\n", ' ', $out );
$out = Html::rawElement( 'code', $htmlAttribs, $out );
} else {
// Not entirely sure what benefit this provides, but it was here already
$htmlAttribs['class'] .= ' ' . 'mw-content-' . $htmlAttribs['dir'];
// Unwrap Pygments output to provide our own wrapper. We can't just always use the 'nowrap'
// option (pass 'inline'), since it disables other useful things like line highlighting.
// Tolerate absence of quotes for Html::element() and wgWellFormedXml=false.
if ( $out !== '' ) {
$m = [];
if ( preg_match( '/^<div class="?mw-highlight"?>(.*)<\/div>$/s', trim( $out ), $m ) ) {
$out = trim( $m[1] );
} else {
throw new MWException( 'Unexpected output from Pygments encountered' );
}
}
// Use 'nowiki' strip marker to prevent list processing (also known as doBlockLevels()).
// However, leave the wrapping <div/> outside to prevent <p/>-wrapping.
$marker = $parser::MARKER_PREFIX . '-syntaxhighlightinner-' .
sprintf( '%08X', $parser->mMarkerIndex++ ) . $parser::MARKER_SUFFIX;
$parser->mStripState->addNoWiki( $marker, $out );
$out = Html::openElement( 'div', $htmlAttribs ) .
$marker .
Html::closeElement( 'div' );
}
// Register CSS
$parser->getOutput()->addModuleStyles( 'ext.pygments' );
return $out;
}
/**
* @return string
*/
public static function getPygmentizePath() {
global $wgPygmentizePath;
// If $wgPygmentizePath is unset, use the bundled copy.
if ( $wgPygmentizePath === false ) {
$wgPygmentizePath = __DIR__ . '/../pygments/pygmentize';
}
return $wgPygmentizePath;
}
/**
* @param string $code
* @param bool $inline
*/
private static function plainCodeWrap( $code, $inline ) {
if ( $inline ) {
return htmlspecialchars( $code, ENT_NOQUOTES );
}
return Html::rawElement(
'div',
[ 'class' => self::HIGHLIGHT_CSS_CLASS ],
Html::element( 'pre', [], $code )
);
}
/**
* Highlight a code-block using a particular lexer.
*
* @param string $code Code to highlight.
* @param string|null $lang Language name, or null to use plain markup.
* @param array $args Associative array of additional arguments.
* If it contains a 'line' key, the output will include line numbers.
* If it includes a 'highlight' key, the value will be parsed as a
* comma-separated list of lines and line-ranges to highlight.
* If it contains a 'start' key, the value will be used as the line at which to
* start highlighting.
* If it contains a 'inline' key, the output will not be wrapped in `<div><pre/></div>`.
* @return Status Status object, with HTML representing the highlighted
* code as its value.
*/
public static function highlight( $code, $lang = null, $args = [] ) {
$status = new Status;
$lexer = self::getLexer( $lang );
if ( $lexer === null && $lang !== null ) {
$status->warning( 'syntaxhighlight-error-unknown-language', $lang );
}
// For empty tag, output nothing instead of empty <pre>.
if ( $code === '' ) {
$status->value = '';
return $status;
}
$length = strlen( $code );
if ( strlen( $code ) > self::HIGHLIGHT_MAX_BYTES ) {
// Disable syntax highlighting
$lexer = null;
$status->warning(
'syntaxhighlight-error-exceeds-size-limit',
$length,
self::HIGHLIGHT_MAX_BYTES
);
} elseif ( Shell::isDisabled() ) {
// Disable syntax highlighting
$lexer = null;
$status->warning( 'syntaxhighlight-error-pygments-invocation-failure' );
wfWarn(
'MediaWiki determined that it cannot invoke Pygments. ' .
'As a result, SyntaxHighlight_GeSHi will not perform any syntax highlighting. ' .
'See the debug log for details: ' .
'https://www.mediawiki.org/wiki/Manual:$wgDebugLogFile'
);
}
$inline = isset( $args['inline'] );
if ( $inline ) {
$code = trim( $code );
}
if ( $lexer === null ) {
// When syntax highlighting is disabled..
$status->value = self::plainCodeWrap( $code, $inline );
return $status;
}
$options = [
'cssclass' => self::HIGHLIGHT_CSS_CLASS,
'encoding' => 'utf-8',
];
// Line numbers
if ( isset( $args['line'] ) ) {
$options['linenos'] = 'inline';
}
if ( $lexer === 'php' && strpos( $code, '<?php' ) === false ) {
$options['startinline'] = 1;
}
// Highlight specific lines
if ( isset( $args['highlight'] ) ) {
$lines = self::parseHighlightLines( $args['highlight'] );
if ( count( $lines ) ) {
$options['hl_lines'] = implode( ' ', $lines );
}
}
// Starting line number
if ( isset( $args['start'] ) && ctype_digit( $args['start'] ) ) {
$options['linenostart'] = (int)$args['start'];
}
if ( $inline ) {
$options['nowrap'] = 1;
}
$cache = ObjectCache::getMainWANInstance();
$error = null;
$output = $cache->getWithSetCallback(
$cache->makeGlobalKey( 'highlight', self::makeCacheKeyHash( $code, $lexer, $options ) ),
$cache::TTL_MONTH,
function ( $oldValue, &$ttl ) use ( $code, $lexer, $options, &$error ) {
$optionPairs = [];
foreach ( $options as $k => $v ) {
$optionPairs[] = "{$k}={$v}";
}
$result = Shell::command(
self::getPygmentizePath(),
'-l', $lexer,
'-f', 'html',
'-O', implode( ',', $optionPairs )
)
->input( $code )
->restrict( Shell::RESTRICT_DEFAULT | Shell::NO_NETWORK )
->execute();
if ( $result->getExitCode() != 0 ) {
$ttl = WANObjectCache::TTL_UNCACHEABLE;
$error = $result->getStderr();
return null;
}
return $result->getStdout();
}
);
if ( $error !== null || $output === null ) {
$status->warning( 'syntaxhighlight-error-pygments-invocation-failure' );
wfWarn( 'Failed to invoke Pygments: ' . $error );
// Fall back to preformatted code without syntax highlighting
$output = self::plainCodeWrap( $code, $inline );
}
if ( $inline ) {
// We've already trimmed the input $code before highlighting,
// but pygment's standard out adds a line break afterwards,
// which would then be preserved in the paragraph that wraps this,
// and become visible as a space. Avoid that.
$output = trim( $output );
}
$status->value = $output;
return $status;
}
/**
* Construct a cache key for the results of a Pygments invocation.
*
* @param string $code Code to be highlighted.
* @param string $lexer Lexer name.
* @param array $options Options array.
* @return string Cache key.
*/
private static function makeCacheKeyHash( $code, $lexer, $options ) {
$optionString = FormatJson::encode( $options, false, FormatJson::ALL_OK );
return md5( "{$code}|{$lexer}|{$optionString}|" . self::CACHE_VERSION );
}
/**
* Take an input specifying a list of lines to highlight, returning
* a raw list of matching line numbers.
*
* Input is comma-separated list of lines or line ranges.
*
* @param string $lineSpec
* @return int[] Line numbers.
*/
protected static function parseHighlightLines( $lineSpec ) {
$lines = [];
$values = array_map( 'trim', explode( ',', $lineSpec ) );
foreach ( $values as $value ) {
if ( ctype_digit( $value ) ) {
$lines[] = (int)$value;
} elseif ( strpos( $value, '-' ) !== false ) {
list( $start, $end ) = array_map( 'trim', explode( '-', $value ) );
if ( self::validHighlightRange( $start, $end ) ) {
for ( $i = intval( $start ); $i <= $end; $i++ ) {
$lines[] = $i;
}
}
}
if ( count( $lines ) > self::HIGHLIGHT_MAX_LINES ) {
$lines = array_slice( $lines, 0, self::HIGHLIGHT_MAX_LINES );
break;
}
}
return $lines;
}
/**
* Validate a provided input range
* @param int $start
* @param int $end
* @return bool
*/
protected static function validHighlightRange( $start, $end ) {
// Since we're taking this tiny range and producing a an
// array of every integer between them, it would be trivial
// to DoS the system by asking for a huge range.
// Impose an arbitrary limit on the number of lines in a
// given range to reduce the impact.
return ctype_digit( $start ) &&
ctype_digit( $end ) &&
$start > 0 &&
$start < $end &&
$end - $start < self::HIGHLIGHT_MAX_LINES;
}
/**
* Hook into Content::getParserOutput to provide syntax highlighting for
* script content.
*
* @param Content $content
* @param Title $title
* @param int $revId
* @param ParserOptions $options
* @param bool $generateHtml
* @param ParserOutput &$output
* @return bool
* @since MW 1.21
*/
public static function onContentGetParserOutput( Content $content, Title $title,
$revId, ParserOptions $options, $generateHtml, ParserOutput &$output
) {
global $wgParser, $wgTextModelsToParse;
if ( !$generateHtml ) {
// Nothing special for us to do, let MediaWiki handle this.
return true;
}
// Determine the language
$extension = ExtensionRegistry::getInstance();
$models = $extension->getAttribute( 'SyntaxHighlightModels' );
$model = $content->getModel();
if ( !isset( $models[$model] ) ) {
// We don't care about this model, carry on.
return true;
}
$lexer = $models[$model];
// Hope that $wgSyntaxHighlightModels does not contain silly types.
$text = ContentHandler::getContentText( $content );
if ( !$text ) {
// Oops! Non-text content? Let MediaWiki handle this.
return true;
}
// Parse using the standard parser to get links etc. into the database, HTML is replaced below.
// We could do this using $content->fillParserOutput(), but alas it is 'protected'.
if ( $content instanceof TextContent && in_array( $model, $wgTextModelsToParse ) ) {
$output = $wgParser->parse( $text, $title, $options, true, true, $revId );
}
$status = self::highlight( $text, $lexer );
if ( !$status->isOK() ) {
return true;
}
$out = $status->getValue();
$output->addModuleStyles( 'ext.pygments' );
$output->setText( '<div dir="ltr">' . $out . '</div>' );
// Inform MediaWiki that we have parsed this page and it shouldn't mess with it.
return false;
}
/**
* Hook to provide syntax highlighting for API pretty-printed output
*
* @param IContextSource $context
* @param string $text
* @param string $mime
* @param string $format
* @since MW 1.24
* @return bool
*/
public static function onApiFormatHighlight( IContextSource $context, $text, $mime, $format ) {
if ( !isset( self::$mimeLexers[$mime] ) ) {
return true;
}
$lexer = self::$mimeLexers[$mime];
$status = self::highlight( $text, $lexer );
if ( !$status->isOK() ) {
return true;
}
$out = $status->getValue();
if ( preg_match( '/^<pre([^>]*)>/i', $out, $m ) ) {
$attrs = Sanitizer::decodeTagAttributes( $m[1] );
$attrs['class'] .= ' api-pretty-content';
$encodedAttrs = Sanitizer::safeEncodeTagAttributes( $attrs );
$out = '<pre' . $encodedAttrs. '>' . substr( $out, strlen( $m[0] ) );
}
$output = $context->getOutput();
$output->addModuleStyles( 'ext.pygments' );
$output->addHTML( '<div dir="ltr">' . $out . '</div>' );
// Inform MediaWiki that we have parsed this page and it shouldn't mess with it.
return false;
}
/**
* Conditionally register resource loader modules that depends on the
* VisualEditor MediaWiki extension.
*
* @param ResourceLoader &$resourceLoader
*/
public static function onResourceLoaderRegisterModules( &$resourceLoader ) {
if ( ! ExtensionRegistry::getInstance()->isLoaded( 'VisualEditor' ) ) {
return;
}
$resourceLoader->register( 'ext.geshi.visualEditor', [
'class' => ResourceLoaderSyntaxHighlightVisualEditorModule::class,
'localBasePath' => __DIR__ . '/../modules',
'remoteExtPath' => 'SyntaxHighlight_GeSHi/modules',
'scripts' => [
've-syntaxhighlight/ve.dm.MWSyntaxHighlightNode.js',
've-syntaxhighlight/ve.ce.MWSyntaxHighlightNode.js',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightWindow.js',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightDialog.js',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightDialogTool.js',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightInspector.js',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightInspectorTool.js',
],
'styles' => [
've-syntaxhighlight/ve.ce.MWSyntaxHighlightNode.css',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightDialog.css',
've-syntaxhighlight/ve.ui.MWSyntaxHighlightInspector.css',
],
'dependencies' => [
'ext.visualEditor.mwcore',
],
'messages' => [
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-code',
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-language',
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-none',
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-showlines',
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-startingline',
'syntaxhighlight-visualeditor-mwsyntaxhighlightinspector-title',
],
'targets' => [ 'desktop', 'mobile' ],
] );
}
/**
* Backward-compatibility shim for extensions.
* @deprecated since MW 1.25
*/
public static function prepare( $text, $lang ) {
wfDeprecated( __METHOD__ );
return new GeSHi( self::highlight( $text, $lang )->getValue() );
}
/**
* Backward-compatibility shim for extensions.
* @deprecated since MW 1.25
* @param GeSHi $geshi
* @return string
*/
public static function buildHeadItem( $geshi ) {
wfDeprecated( __METHOD__ );
$geshi->parse_code();
return '';
}
}
class_alias( SyntaxHighlight::class, 'SyntaxHighlight_GeSHi' );