mediawiki-extensions-Math/MathLaTeXML.php
Moritz Schubotz (Physikerwelt) c5b0b15d8f Fix MathJax centers equations
* Removes the MathJax heuristics that decides
  if equations are centered or left-aligned.
* Introduces the attribute display to specify
  if the math element is rendered in inline,
  display, or inline-displaystyle.
* add css rules for display / inline math images

Bug: 61051
Change-Id: Iba69903f781f0cb1606b8ddcffb90fb86c9b229b
2014-04-06 21:58:30 +00:00

298 lines
8.7 KiB
PHP

<?php
/**
* MediaWiki math extension
*
* (c)2012 Moritz Schubotz
* GPLv2 license; info in main package.
*
* Contains the driver function for the LaTeXML daemon
* @file
*/
class MathLaTeXML extends MathRenderer {
/**
* @var String settings for LaTeXML daemon
*/
private $LaTeXMLSettings = '';
/**
* Converts an array with LaTeXML settings to a URL encoded String.
* If the argument is a string the input will be returned.
* Thus the function has projector properties and can be applied a second time safely.
* @param (string|array) $array
* @return string
*/
public function serializeSettings( $array ) {
if ( !is_array( $array ) ) {
return $array;
} else {
// removes the [1] [2]... for the unnamed subarrays since LaTeXML
// assigns multiple values to one key e.g.
// preload=amsmath.sty&preload=amsthm.sty&preload=amstext.sty
return preg_replace( '|\%5B\d+\%5D|', '', wfArrayToCgi( $array ) ) ;
}
}
/**
* Gets the settings for the LaTeXML daemon.
* @global type $wgMathDefaultLaTeXMLSetting
* @return string
*/
public function getLaTeXMLSettings() {
global $wgMathDefaultLaTeXMLSetting;
if ( $this->LaTeXMLSettings ) {
return $this->LaTeXMLSettings;
} else {
return $wgMathDefaultLaTeXMLSetting;
}
}
/**
* Sets the settings for the LaTeXML daemon.
* The settings affect only the current instance of the class.
* For a list of possible settings see:
* http://dlmf.nist.gov/LaTeXML/manual/commands/latexmlpost.xhtml
* An empty value indicates to use the default settings.
* @param string|array $settings
*/
public function setLaTeXMLSettings( $settings ) {
$this->LaTeXMLSettings = $settings;
}
/* (non-PHPdoc)
* @see MathRenderer::render()
*/
public function render( $forceReRendering = false ) {
wfProfileIn( __METHOD__ );
if ( $forceReRendering ) {
$this->setPurge( true );
}
if ( $this->renderingRequired() ) {
$res = $this->doRender( );
if ( ! $res ) {
wfProfileOut( __METHOD__ );
return $this->getLastError();
}
}
$result = $this->getMathMLTag();
wfProfileOut( __METHOD__ );
return $result;
}
/**
* Helper function to checks if the math tag must be rendered.
* @return boolean
*/
private function renderingRequired() {
if ( $this->isPurge() ) {
wfDebugLog( "Math", "Rerendering was requested." );
return true;
} else {
$dbres = $this->readFromDatabase();
if ( $dbres ) {
if ( self::isValidMathML( $this->getMathml() ) ) {
wfDebugLog( "Math", "Valid entry found in database." );
return false;
} else {
wfDebugLog( "Math", "Malformatted entry found in database" );
return true;
}
} else {
wfDebugLog( "Math", "No entry found in database." );
return true;
}
}
}
/**
* Performs a HTTP Post request to the given host.
* Uses $wgMathLaTeXMLTimeout as timeout.
* Generates error messages on failure
* @see Http::post()
*
* @global type $wgMathLaTeXMLTimeout
* @param string $host
* @param string $post the encoded post request
* @param mixed $res the result
* @param mixed $error the formatted error message or null
* @param String $httpRequestClass class name of MWHttpRequest (needed for testing only)
* @return boolean success
*/
public function makeRequest( $host, $post, &$res, &$error = '', $httpRequestClass = 'MWHttpRequest' ) {
global $wgMathLaTeXMLTimeout;
wfProfileIn( __METHOD__ );
$error = '';
$res = null;
$options = array( 'method' => 'POST', 'postData' => $post, 'timeout' => $wgMathLaTeXMLTimeout );
$req = $httpRequestClass::factory( $host, $options );
$status = $req->execute();
if ( $status->isGood() ) {
$res = $req->getContent();
wfProfileOut( __METHOD__ );
return true;
} else {
if ( $status->hasMessage( 'http-timed-out' ) ) {
$error = $this->getError( 'math_latexml_timeout', $host );
$res = false;
wfDebugLog( "Math", "\nLaTeXML Timeout:"
. var_export( array( 'post' => $post, 'host' => $host
, 'timeout' => $wgMathLaTeXMLTimeout ), true ) . "\n\n" );
} else {
// for any other unkonwn http error
$errormsg = $status->getHtml();
$error = $this->getError( 'math_latexml_invalidresponse', $host, $errormsg );
wfDebugLog( "Math", "\nLaTeXML NoResponse:"
. var_export( array( 'post' => $post, 'host' => $host
, 'errormsg' => $errormsg ), true ) . "\n\n" );
}
wfProfileOut( __METHOD__ );
return false;
}
}
/* (non-PHPdoc)
* @see MathRenderer::writeCache()
*/
public function writeCache() {
if ( $this->isChanged() ) {
$this->writeToDatabase();
}
}
/**
* Picks a LaTeXML daemon.
* If more than one demon are availible one is chosen from the
* $wgMathLaTeXMLUrl array.
* @return string
*/
private static function pickHost() {
global $wgMathLaTeXMLUrl;
if ( is_array( $wgMathLaTeXMLUrl ) ) {
$host = array_rand( $wgMathLaTeXMLUrl );
} else {
$host = $wgMathLaTeXMLUrl;
}
wfDebugLog( "Math", "picking host " . $host );
return $host;
}
/**
* Calculates the HTTP POST Data for the request. Depends on the settings
* and the input string only.
* @return string HTTP POST data
*/
public function getPostData() {
$tex = $this->getTex();
if ( $this->getMathStyle() == MW_MATHSTYLE_INLINE_DISPLAYSTYLE ) {
// In MW_MATHSTYLE_INLINE_DISPLAYSTYLE the old
// texvc behavior is reproduced:
// The equation is rendered in displaystyle
// (texvc used $$ $tex $$ to render)
// but the equation is not centered.
$tex = '{\displaystyle ' . $tex . '}';
}
$texcmd = rawurlencode( $tex );
$settings = $this->serializeSettings( $this->getLaTeXMLSettings( ) );
return $settings. '&tex=' . $texcmd;
}
/**
* Does the actual web request to convert TeX to MathML.
* @return boolean
*/
private function doRender( ) {
wfProfileIn( __METHOD__ );
$host = self::pickHost();
$post = $this->getPostData();
$this->lastError = '';
if ( $this->makeRequest( $host, $post, $res, $this->lastError ) ) {
$result = json_decode( $res );
if ( json_last_error() === JSON_ERROR_NONE ) {
if ( self::isValidMathML( $result->result ) ) {
$this->setMathml( $result->result );
wfProfileOut( __METHOD__ );
return true;
} else {
// Do not print bad mathml. It's probably too verbose and might
// mess up the browser output.
$this->lastError = $this->getError( 'math_latexml_invalidxml', $host );
wfDebugLog( "Math", "\nLaTeXML InvalidMathML:"
. var_export( array( 'post' => $post, 'host' => $host
, 'result' => $result ), true ) . "\n\n" );
wfProfileOut( __METHOD__ );
return false;
}
} else {
$this->lastError = $this->getError( 'math_latexml_invalidjson', $host );
wfDebugLog( "Math", "\nLaTeXML InvalidJSON:"
. var_export( array( 'post' => $post, 'host' => $host
, 'res' => $res ), true ) . "\n\n" );
wfProfileOut( __METHOD__ );
return false;
}
} else {
// Error message has already been set.
wfProfileOut( __METHOD__ );
return false;
}
}
/**
* Checks if the input is valid MathML,
* and if the root element has the name math
* @param string $XML
* @return boolean
*/
static public function isValidMathML( $XML ) {
$out = false;
// depends on https://gerrit.wikimedia.org/r/#/c/66365/
if ( ! is_callable( 'XmlTypeCheck::newFromString' ) ) {
$msg = wfMessage( 'math_latexml_xmlversion' )->inContentLanguage()->escaped();
trigger_error( $msg, E_USER_NOTICE );
wfDebugLog( 'Math', $msg );
return true;
}
$xmlObject = new XmlTypeCheck( $XML, null, false );
if ( ! $xmlObject->wellFormed ) {
wfDebugLog( "Math", "XML validation error:\n " . var_export( $XML, true ) . "\n" );
} else {
$name = $xmlObject->getRootElement();
$name = str_replace( 'http://www.w3.org/1998/Math/MathML:', '', $name );
if ( $name == "math" or $name == "table" or $name == "div" ) {
$out = true;
} else {
wfDebugLog( "Math", "got wrong root element " . $name );
}
}
return $out;
}
/**
* Internal version of @link self::embedMathML
* @return string
* @return html element with rendered math
*/
private function getMathMLTag() {
return self::embedMathML( $this->getMathml(), urldecode( $this->getTex() ) );
}
/**
* Embeds the MathML-XML element in a HTML span element with class tex
* @param string $mml : the MathML string
* @param string $tagId : optional tagID for references like (pagename#equation2)
* @param bool $attribs
* @return html element with rendered math
*/
public static function embedMathML( $mml, $tagId = '', $attribs = false ) {
$mml = str_replace( "\n", " ", $mml );
if ( ! $attribs ) {
$attribs = array( 'class' => 'tex', 'dir' => 'ltr' );
if ( $tagId ) {
$attribs['id'] = $tagId;
}
$attribs = Sanitizer::validateTagAttributes( $attribs, 'span' );
}
return Xml::tags( 'span', $attribs, $mml );
}
}