2 # Copyright (C) 2009 Aryeh Gregor
3 # http://www.mediawiki.org/
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.
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.
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
21 * This class is a collection of static functions that serve two purposes:
23 * 1) Implement any algorithms specified by HTML 5, or other HTML
24 * specifications, in a convenient and self-contained way.
26 * 2) Allow HTML elements to be conveniently and safely generated, like the
27 * current Xml class but a) less confused (Xml supports HTML-specific things,
28 * but only sometimes!) and b) not necessarily confined to XML-compatible
31 * There are two important configuration options this class uses:
33 * $wgHtml5: If this is set to false, then all output should be valid XHTML 1.0
35 * $wgWellFormedXml: If this is set to true, then all output should be
36 * well-formed XML (quotes on attributes, self-closing tags, etc.).
38 * This class is meant to be confined to utility functions that are called from
39 * trusted code paths. It does not do enforcement of policy like not allowing
43 # List of void elements from HTML 5, section 9.1.2 as of 2009-08-10
44 private static $voidElements = array(
61 # Boolean attributes, which may have the value omitted entirely. Manually
62 # collected from the HTML 5 spec as of 2009-08-10.
63 private static $boolAttribs = array(
87 * Returns an HTML element in a string. The major advantage here over
88 * manually typing out the HTML is that it will escape all attribute
89 * values. If you're hardcoding all the attributes, or there are none, you
90 * should probably type out the string yourself.
92 * This is quite similar to Xml::tags(), but it implements some useful
93 * HTML-specific logic. For instance, there is no $allowShortTag
94 * parameter: the closing tag is magically omitted if $element has an empty
95 * content model. If $wgWellFormedXml is false, then a few bytes will be
96 * shaved off the HTML output as well. In the future, other HTML-specific
97 * features might be added, like allowing arrays for the values of
98 * attributes like class= and media=.
100 * @param $element string The element's name, e.g., 'a'
101 * @param $attribs array Associative array of attributes, e.g., array(
102 * 'href' => 'http://www.mediawiki.org/' ). See expandAttributes() for
103 * further documentation.
104 * @param $contents string The raw HTML contents of the element: *not*
106 * @return string Raw HTML
108 public static function rawElement( $element, $attribs = array(), $contents = '' ) {
109 global $wgHtml5, $wgWellFormedXml;
110 $attribs = (array)$attribs;
111 # This is not required in HTML 5, but let's do it anyway, for
112 # consistency and better compression.
113 $element = strtolower( $element );
115 # Remove HTML5-only attributes if we aren't doing HTML5
117 if ( $element == 'input' ) {
118 # Whitelist of valid XHTML1 types
131 if ( isset( $attribs['type'] )
132 && !in_array( $attribs['type'], $validTypes ) ) {
133 # Fall back to type=text, the default
134 unset( $attribs['type'] );
137 if ( $element == 'textarea' && isset( $attribs['maxlength'] ) ) {
138 unset( $attribs['maxlength'] );
140 # Here we're blacklisting some HTML5-only attributes...
141 $html5attribs = array(
153 foreach ( $html5attribs as $badAttr ) {
154 unset( $attribs[$badAttr] );
158 $start = "<$element" . self
::expandAttributes(
159 self
::dropDefaults( $element, $attribs ) );
160 if ( in_array( $element, self
::$voidElements ) ) {
161 if ( $wgWellFormedXml ) {
166 return "$start>$contents</$element>";
171 * Identical to rawElement(), but HTML-escapes $contents (like
174 public static function element( $element, $attribs = array(), $contents = '' ) {
175 return self
::rawElement( $element, $attribs, strtr( $contents, array(
176 # There's no point in escaping quotes, >, etc. in the contents of
184 * Given an element name and an associative array of element attributes,
185 * return an array that is functionally identical to the input array, but
186 * possibly smaller. In particular, attributes might be stripped if they
187 * are given their default values.
189 * This method is not guaranteed to remove all redundant attributes, only
190 * some common ones and some others selected arbitrarily at random. It
191 * only guarantees that the output array should be functionally identical
192 * to the input array (currently per the HTML 5 draft as of 2009-09-06).
194 * @param $element string Name of the element, e.g., 'a'
195 * @param $attribs array Associative array of attributes, e.g., array(
196 * 'href' => 'http://www.mediawiki.org/' ). See expandAttributes() for
197 * further documentation.
198 * @return array An array of attributes functionally identical to $attribs
200 private static function dropDefaults( $element, $attribs ) {
201 # Don't bother doing anything if we aren't outputting HTML5; it's too
202 # much of a pain to maintain two sets of defaults.
208 static $attribDefaults = array(
209 'area' => array( 'shape' => 'rect' ),
211 'formaction' => 'GET',
212 'formenctype' => 'application/x-www-form-urlencoded',
219 'command' => array( 'type' => 'command' ),
222 'autocomplete' => 'on',
223 'enctype' => 'application/x-www-form-urlencoded',
226 'formaction' => 'GET',
230 'keygen' => array( 'keytype' => 'rsa' ),
231 'link' => array( 'media' => 'all' ),
232 'menu' => array( 'type' => 'list' ),
233 # Note: the use of text/javascript here instead of other JavaScript
234 # MIME types follows the HTML 5 spec.
235 'script' => array( 'type' => 'text/javascript' ),
238 'type' => 'text/css',
240 'textarea' => array( 'wrap' => 'soft' ),
243 $element = strtolower( $element );
245 foreach ( $attribs as $attrib => $value ) {
246 $lcattrib = strtolower( $attrib );
247 $value = strval( $value );
249 # Simple checks using $attribDefaults
250 if ( isset( $attribDefaults[$element][$lcattrib] ) &&
251 $attribDefaults[$element][$lcattrib] == $value ) {
252 unset( $attribs[$attrib] );
255 if ( $lcattrib == 'class' && $value == '' ) {
256 unset( $attribs[$attrib] );
261 if ( $element === 'link' && isset( $attribs['type'] )
262 && strval( $attribs['type'] ) == 'text/css' ) {
263 unset( $attribs['type'] );
265 if ( $element === 'select' && isset( $attribs['size'] ) ) {
266 if ( in_array( 'multiple', $attribs )
267 ||
( isset( $attribs['multiple'] ) && $attribs['multiple'] !== false )
270 if ( strval( $attribs['size'] ) == '4' ) {
271 unset( $attribs['size'] );
275 if ( strval( $attribs['size'] ) == '1' ) {
276 unset( $attribs['size'] );
285 * Given an associative array of element attributes, generate a string
286 * to stick after the element name in HTML output. Like array( 'href' =>
287 * 'http://www.mediawiki.org/' ) becomes something like
288 * ' href="http://www.mediawiki.org"'. Again, this is like
289 * Xml::expandAttributes(), but it implements some HTML-specific logic.
290 * For instance, it will omit quotation marks if $wgWellFormedXml is false,
291 * and will treat boolean attributes specially.
293 * @param $attribs array Associative array of attributes, e.g., array(
294 * 'href' => 'http://www.mediawiki.org/' ). Values will be HTML-escaped.
295 * A value of false means to omit the attribute. For boolean attributes,
296 * you can omit the key, e.g., array( 'checked' ) instead of
297 * array( 'checked' => 'checked' ) or such.
298 * @return string HTML fragment that goes between element name and '>'
299 * (starting with a space if at least one attribute is output)
301 public static function expandAttributes( $attribs ) {
302 global $wgHtml5, $wgWellFormedXml;
305 $attribs = (array)$attribs;
306 foreach ( $attribs as $key => $value ) {
307 if ( $value === false ) {
311 # For boolean attributes, support array( 'foo' ) instead of
312 # requiring array( 'foo' => 'meaningless' ).
314 && in_array( strtolower( $value ), self
::$boolAttribs ) ) {
318 # Not technically required in HTML 5, but required in XHTML 1.0,
319 # and we'd like consistency and better compression anyway.
320 $key = strtolower( $key );
322 # See the "Attributes" section in the HTML syntax part of HTML 5,
323 # 9.1.2.3 as of 2009-08-10. Most attributes can have quotation
324 # marks omitted, but not all. (Although a literal " is not
325 # permitted, we don't check for that, since it will be escaped
328 # See also research done on further characters that need to be
329 # escaped: http://code.google.com/p/html5lib/issues/detail?id=93
330 $badChars = "\\x00- '=<>`/\x{00a0}\x{1680}\x{180e}\x{180F}\x{2000}\x{2001}"
331 . "\x{2002}\x{2003}\x{2004}\x{2005}\x{2006}\x{2007}\x{2008}\x{2009}"
332 . "\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}";
333 if ( $wgWellFormedXml ||
$value === ''
334 ||
preg_match( "![$badChars]!u", $value ) ) {
340 if ( in_array( $key, self
::$boolAttribs ) ) {
341 # In XHTML 1.0 Transitional, the value needs to be equal to the
342 # key. In HTML 5, we can leave the value empty instead. If we
343 # don't need well-formed XML, we can omit the = entirely.
344 if ( !$wgWellFormedXml ) {
346 } elseif ( $wgHtml5 ) {
347 $ret .= " $key=\"\"";
349 $ret .= " $key=\"$key\"";
352 # Apparently we need to entity-encode \n, \r, \t, although the
353 # spec doesn't mention that. Since we're doing strtr() anyway,
354 # and we don't need <> escaped here, we may as well not call
355 # htmlspecialchars(). FIXME: verify that we actually need to
356 # escape \n\r\t here, and explain why, exactly.
358 # We could call Sanitizer::encodeAttribute() for this, but we
359 # don't because we're stubborn and like our marginal savings on
360 # byte size from not having to encode unnecessary quotes.
368 if ( $wgWellFormedXml ) {
369 # '<' must be escaped in attributes for XML for some
370 # reason, per spec: http://www.w3.org/TR/xml/#NT-AttValue
373 $ret .= " $key=$quote" . strtr( $value, $map ) . $quote;
380 * Output a <script> tag with the given contents. TODO: do some useful
381 * escaping as well, like if $contents contains literal '</script>' or (for
382 * XML) literal "]]>".
384 * @param $contents string JavaScript
385 * @return string Raw HTML
387 public static function inlineScript( $contents ) {
388 global $wgHtml5, $wgJsMimeType, $wgWellFormedXml;
392 $attrs['type'] = $wgJsMimeType;
394 if ( $wgWellFormedXml && preg_match( '/[<&]/', $contents ) ) {
395 $contents = "/*<![CDATA[*/$contents/*]]>*/";
397 return self
::rawElement( 'script', $attrs, $contents );
401 * Output a <script> tag linking to the given URL, e.g.,
402 * <script src=foo.js></script>.
405 * @return string Raw HTML
407 public static function linkedScript( $url ) {
408 global $wgHtml5, $wgJsMimeType;
410 $attrs = array( 'src' => $url );
412 $attrs['type'] = $wgJsMimeType;
414 return self
::element( 'script', $attrs );
418 * Output a <style> tag with the given contents for the given media type
419 * (if any). TODO: do some useful escaping as well, like if $contents
420 * contains literal '</style>' (admittedly unlikely).
422 * @param $contents string CSS
423 * @param $media mixed A media type string, like 'screen'
424 * @return string Raw HTML
426 public static function inlineStyle( $contents, $media = 'all' ) {
427 global $wgWellFormedXml;
429 if ( $wgWellFormedXml && preg_match( '/[<&]/', $contents ) ) {
430 $contents = "/*<![CDATA[*/$contents/*]]>*/";
432 return self
::rawElement( 'style', array(
433 'type' => 'text/css',
439 * Output a <link rel=stylesheet> linking to the given URL for the given
440 * media type (if any).
443 * @param $media mixed A media type string, like 'screen'
444 * @return string Raw HTML
446 public static function linkedStyle( $url, $media = 'all' ) {
447 return self
::element( 'link', array(
448 'rel' => 'stylesheet',
450 'type' => 'text/css',
456 * Convenience function to produce an <input> element. This supports the
457 * new HTML 5 input types and attributes, and will silently strip them if
460 * @param $name string name attribute
461 * @param $value mixed value attribute
462 * @param $type string type attribute
463 * @param $attribs array Associative array of miscellaneous extra
464 * attributes, passed to Html::element()
465 * @return string Raw HTML
467 public static function input( $name, $value = '', $type = 'text', $attribs = array() ) {
468 $attribs['type'] = $type;
469 $attribs['value'] = $value;
470 $attribs['name'] = $name;
472 return self
::element( 'input', $attribs );
476 * Convenience function to produce an input element with type=hidden, like
479 * @param $name string name attribute
480 * @param $value string value attribute
481 * @param $attribs array Associative array of miscellaneous extra
482 * attributes, passed to Html::element()
483 * @return string Raw HTML
485 public static function hidden( $name, $value, $attribs = array() ) {
486 return self
::input( $name, $value, 'hidden', $attribs );
490 * Convenience function to produce an <input> element. This supports leaving
491 * out the cols= and rows= which Xml requires and are required by HTML4/XHTML
492 * but not required by HTML5 and will silently set cols="" and rows="" if
493 * $wgHtml5 is false and cols and rows are omitted (HTML4 validates present
494 * but empty cols="" and rows="" as valid).
496 * @param $name string name attribute
497 * @param $value string value attribute
498 * @param $attribs array Associative array of miscellaneous extra
499 * attributes, passed to Html::element()
500 * @return string Raw HTML
502 public static function textarea( $name, $value = '', $attribs = array() ) {
504 $attribs['name'] = $name;
506 if ( !array_key_exists('cols', $attribs) )
507 $attribs['cols'] = "";
508 if ( !array_key_exists('rows', $attribs) )
509 $attribs['rows'] = "";
511 return self
::element( 'textarea', $attribs, $value );