Файл: framework/parsers/ShortcodeParser.php
Строк: 713
<?php
/**
* A simple parser that allows you to map BBCode-like "shortcodes" to an arbitrary callback.
* It is a simple regex based parser that allows you to replace simple bbcode-like tags
* within a HTMLText or HTMLVarchar field when rendered into a template. The API is inspired by and very similar to the
* [Wordpress implementation](http://codex.wordpress.org/Shortcode_API) of shortcodes.
*
* @see http://doc.silverstripe.org/framework/en/reference/shortcodes
* @package framework
* @subpackage misc
*/
class ShortcodeParser extends Object {
public function img_shortcode($attrs) {
return "<img src='".$attrs['src']."'>";
}
protected static $instances = array();
protected static $active_instance = 'default';
// --------------------------------------------------------------------------------------------------------------
protected $shortcodes = array();
// --------------------------------------------------------------------------------------------------------------
/**
* Get the {@link ShortcodeParser} instance that is attached to a particular identifier.
*
* @param string $identifier Defaults to "default".
* @return ShortcodeParser
*/
public static function get($identifier = 'default') {
if(!array_key_exists($identifier, self::$instances)) {
self::$instances[$identifier] = static::create();
}
return self::$instances[$identifier];
}
/**
* Get the currently active/default {@link ShortcodeParser} instance.
*
* @return ShortcodeParser
*/
public static function get_active() {
return static::get(self::$active_instance);
}
/**
* Set the identifier to use for the current active/default {@link ShortcodeParser} instance.
*
* @param string $identifier
*/
public static function set_active($identifier) {
self::$active_instance = (string) $identifier;
}
// --------------------------------------------------------------------------------------------------------------
/**
* Register a shortcode, and attach it to a PHP callback.
*
* The callback for a shortcode will have the following arguments passed to it:
* - Any parameters attached to the shortcode as an associative array (keys are lower-case).
* - Any content enclosed within the shortcode (if it is an enclosing shortcode). Note that any content within
* this will not have been parsed, and can optionally be fed back into the parser.
* - The {@link ShortcodeParser} instance used to parse the content.
* - The shortcode tag name that was matched within the parsed content.
* - An associative array of extra information about the shortcode being parsed.
*
* @param string $shortcode The shortcode tag to map to the callback - normally in lowercase_underscore format.
* @param callback $callback The callback to replace the shortcode with.
*/
public function register($shortcode, $callback) {
if(is_callable($callback)) $this->shortcodes[$shortcode] = $callback;
}
/**
* Check if a shortcode has been registered.
*
* @param string $shortcode
* @return bool
*/
public function registered($shortcode) {
return array_key_exists($shortcode, $this->shortcodes);
}
/**
* Remove a specific registered shortcode.
*
* @param string $shortcode
*/
public function unregister($shortcode) {
if($this->registered($shortcode)) unset($this->shortcodes[$shortcode]);
}
/**
* Remove all registered shortcodes.
*/
public function clear() {
$this->shortcodes = array();
}
/**
* Call a shortcode and return its replacement text
* Returns false if the shortcode isn't registered
*/
public function callShortcode($tag, $attributes, $content, $extra = array()) {
if (!$tag || !isset($this->shortcodes[$tag])) return false;
return call_user_func($this->shortcodes[$tag], $attributes, $content, $this, $tag, $extra);
}
/**
* Return the text to insert in place of a shoprtcode.
* Behaviour in the case of missing shortcodes depends on the setting of ShortcodeParser::$error_behavior.
* @param $tag A map containing the the following keys:
* - 'open': The name of the tag
* - 'attrs': Attributes of the tag
* - 'content': Content of the tag
* @param $extra Extra-meta data
* @param $isHTMLAllowed A boolean indicating whether it's okay to insert HTML tags into the result
*/
function getShortcodeReplacementText($tag, $extra = array(), $isHTMLAllowed = true) {
$content = $this->callShortcode($tag['open'], $tag['attrs'], $tag['content'], $extra);
// Missing tag
if ($content === false) {
if(ShortcodeParser::$error_behavior == ShortcodeParser::ERROR) {
user_error('Unknown shortcode tag '.$tag['open'], E_USER_ERRROR);
}
else if (self::$error_behavior == self::WARN && $isHTMLAllowed) {
$content = '<strong class="warning">'.$tag['text'].'</strong>';
}
else if(ShortcodeParser::$error_behavior == ShortcodeParser::STRIP) {
return '';
}
else {
return $tag['text'];
}
}
return $content;
}
// --------------------------------------------------------------------------------------------------------------
protected function removeNode($node) {
$node->parentNode->removeChild($node);
}
protected function insertAfter($new, $after) {
$parent = $after->parentNode; $next = $after->nextSibling;
if ($next) {
$parent->insertBefore($new, $next);
}
else {
$parent->appendChild($new);
}
}
protected function insertListAfter($new, $after) {
$doc = $after->ownerDocument; $parent = $after->parentNode; $next = $after->nextSibling;
for ($i = 0; $i < $new->length; $i++) {
$imported = $doc->importNode($new->item($i), true);
if ($next) {
$parent->insertBefore($imported, $next);
}
else {
$parent->appendChild($imported);
}
}
}
protected static $marker_class = '--ss-shortcode-marker';
protected static $block_level_elements = array(
'address', 'article', 'aside', 'audio', 'blockquote', 'canvas', 'dd', 'div', 'dl', 'fieldset', 'figcaption',
'figure', 'footer', 'form', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'header', 'hgroup', 'ol', 'output', 'p',
'pre', 'section', 'table', 'ul'
);
protected static $attrrx = '
([^s/'"=,]+) # Name
s* = s*
(?:
(?:'([^']+)') | # Value surrounded by '
(?:"([^"]+)") | # Value surrounded by "
([^s,]]+) # Bare value
)
';
protected static function attrrx() {
return '/'.self::$attrrx.'/xS';
}
protected static $tagrx = '
# HTML Tag
<(?<element>(?:"[^"]*"['"]*|'[^']*'['"]*|[^'">])+)>
| # Opening tag
(?<oesc>[?)
[
(?<open>w+)
[s,]*
(?<attrs> (?: %s [s,]*)* )
/?]
(?<cesc1>]?)
| # Closing tag
[/
(?<close>w+)
]
(?<cesc2>]?)
';
protected static function tagrx() {
return '/'.sprintf(self::$tagrx, self::$attrrx).'/xS';
}
const WARN = 'warn';
const STRIP = 'strip';
const LEAVE = 'leave';
const ERROR = 'error';
public static $error_behavior = self::LEAVE;
/**
* Look through a string that contains shortcode tags and pull out the locations and details
* of those tags
*
* Doesn't support nested shortcode tags
*
* @param string $content
* @return array - The list of tags found. When using an open/close pair, only one item will be in the array,
* with "content" set to the text between the tags
*/
protected function extractTags($content) {
$tags = array();
// Step 1: perform basic regex scan of individual tags
if(preg_match_all(static::tagrx(), $content, $matches, PREG_SET_ORDER | PREG_OFFSET_CAPTURE)) {
foreach($matches as $match) {
// Ignore any elements
if (empty($match['open'][0]) && empty($match['close'][0])) continue;
// Pull the attributes out into a key/value hash
$attrs = array();
if (!empty($match['attrs'][0])) {
preg_match_all(static::attrrx(), $match['attrs'][0], $attrmatches, PREG_SET_ORDER);
foreach ($attrmatches as $attr) {
list($whole, $name, $value) = array_values(array_filter($attr));
$attrs[$name] = $value;
}
}
// And store the indexes, tag details, etc
$tags[] = array(
'text' => $match[0][0],
's' => $match[0][1],
'e' => $match[0][1] + strlen($match[0][0]),
'open' => isset($match['open'][0]) ? $match['open'][0] : null,
'close' => isset($match['close'][0]) ? $match['close'][0] : null,
'attrs' => $attrs,
'content' => '',
'escaped' => !empty($match['oesc'][0]) || !empty($match['cesc1'][0]) || !empty($match['cesc2'][0])
);
}
}
// Step 2: cluster open/close tag pairs into single entries
$i = count($tags);
while($i--) {
if(!empty($tags[$i]['close'])) {
// If the tag just before this one isn't the related opening tag, throw an error
$err = null;
if ($i == 0) {
$err = 'Close tag "'.$tags[$i]['close'].'" is the first found tag, so has no related open tag';
}
else if (!$tags[$i-1]['open']) {
$err = 'Close tag "'.$tags[$i]['close'].'" preceded by another close tag "'.
$tags[$i-1]['close'].'"';
}
else if ($tags[$i]['close'] != $tags[$i-1]['open']) {
$err = 'Close tag "'.$tags[$i]['close'].'" doesn't match preceding open tag "'.
$tags[$i-1]['open'].'"';
}
if($err) {
if(self::$error_behavior == self::ERROR) user_error($err, E_USER_ERRROR);
}
else {
if ($tags[$i]['escaped']) {
if (!$tags[$i-1]['escaped']) {
$tags[$i]['e'] -= 1;
$tags[$i]['escaped'] = false;
}
}
else {
if ($tags[$i-1]['escaped']) {
$tags[$i-1]['s'] += 1;
$tags[$i-1]['escaped'] = false;
}
}
// Otherwise, grab content between tags, save in opening tag & delete the closing one
$tags[$i-1]['text'] = substr($content, $tags[$i-1]['s'], $tags[$i]['e'] - $tags[$i-1]['s']);
$tags[$i-1]['content'] = substr($content, $tags[$i-1]['e'], $tags[$i]['s'] - $tags[$i-1]['e']);
$tags[$i-1]['e'] = $tags[$i]['e'];
unset($tags[$i]);
}
}
}
// Step 3: remove any tags that don't have handlers registered
// Only do this if self::$error_behavior == self::LEAVE
// This is optional but speeds things up.
if(self::$error_behavior == self::LEAVE) {
foreach($tags as $i => $tag) {
if(empty($this->shortcodes[$tag['open']])) {
unset($tags[$i]);
}
}
}
return array_values($tags);
}
/**
* Replaces the shortcode tags extracted by extractTags with HTML element "markers", so that
* we can parse the resulting string as HTML and easily mutate the shortcodes in the DOM
*
* @param string $content - The HTML string with [tag] style shortcodes embedded
* @param array $tags - The tags extracted by extractTags
* @return string - The HTML string with [tag] style shortcodes replaced by markers
*/
protected function replaceTagsWithText($content, $tags, $generator) {
// The string with tags replaced with markers
$str = '';
// The start index of the next tag, remembered as we step backwards through the list
$li = null;
$i = count($tags);
while($i--) {
if ($li === null) $tail = substr($content, $tags[$i]['e']);
else $tail = substr($content, $tags[$i]['e'], $li - $tags[$i]['e']);
if ($tags[$i]['escaped']) {
$str = substr($content, $tags[$i]['s']+1, $tags[$i]['e'] - $tags[$i]['s'] - 2) . $tail . $str;
}
else {
$str = $generator($i, $tags[$i]) . $tail . $str;
}
$li = $tags[$i]['s'];
}
return substr($content, 0, $tags[0]['s']) . $str;
}
/**
* Replace the shortcodes in attribute values with the calculated content
*
* We don't use markers with attributes because there's no point, it's easier to do all the matching
* in-DOM after the XML parse
*
* @param DOMDocument $doc
*/
protected function replaceAttributeTagsWithContent($htmlvalue) {
$attributes = $htmlvalue->query('//@*[contains(.,"[")][contains(.,"]")]');
$parser = $this;
for($i = 0; $i < $attributes->length; $i++) {
$node = $attributes->item($i);
$tags = $this->extractTags($node->nodeValue);
$extra = array('node' => $node, 'element' => $node->ownerElement);
if($tags) {
$node->nodeValue = $this->replaceTagsWithText($node->nodeValue, $tags,
function($idx, $tag) use ($parser, $extra) {
return $parser->getShortcodeReplacementText($tag, $extra, false);
}
);
}
}
}
/**
* Replace the element-scoped tags with markers
*
* @param string $content
*/
protected function replaceElementTagsWithMarkers($content) {
$tags = $this->extractTags($content);
if($tags) {
$markerClass = self::$marker_class;
$content = $this->replaceTagsWithText($content, $tags, function($idx, $tag) use ($markerClass) {
return '<img class="'.$markerClass.'" data-tagid="'.$idx.'" />';
});
}
return array($content, $tags);
}
protected function findParentsForMarkers($nodes) {
$parents = array();
foreach($nodes as $node) {
$parent = $node;
do {
$parent = $parent->parentNode;
}
while($parent instanceof DOMElement &&
!in_array(strtolower($parent->tagName), self::$block_level_elements));
$node->setAttribute('data-parentid', count($parents));
$parents[] = $parent;
}
return $parents;
}
const BEFORE = 'before';
const AFTER = 'after';
const SPLIT = 'split';
const INLINE = 'inline';
/**
* Given a node with represents a shortcode marker and a location string, mutates the DOM to put the
* marker in the compliant location
*
* For shortcodes inserted BEFORE, that location is just before the block container that
* the marker is in
*
* For shortcodes inserted AFTER, that location is just after the block container that
* the marker is in
*
* For shortcodes inserted SPLIT, that location is where the marker is, but the DOM
* is split around it up to the block container the marker is in - for instance,
*
* <p>A<span>B<marker />C</span>D</p>
*
* becomes
*
* <p>A<span>B</span></p><marker /><p><span>C</span>D</p>
*
* For shortcodes inserted INLINE, no modification is needed (but in that case the shortcode handler needs to
* generate only inline blocks)
*
* @param DOMElement $node
* @param int $location - ShortcodeParser::BEFORE, ShortcodeParser::SPLIT or ShortcodeParser::INLINE
*/
protected function moveMarkerToCompliantHome($node, $parent, $location) {
// Move before block parent
if($location == self::BEFORE) {
if (isset($parent->parentNode))
$parent->parentNode->insertBefore($node, $parent);
} else if($location == self::AFTER) {
// Move after block parent
$this->insertAfter($node, $parent);
}
// Split parent at node
else if($location == self::SPLIT) {
$at = $node; $splitee = $node->parentNode;
while($splitee !== $parent->parentNode) {
$spliter = $splitee->cloneNode(false);
$this->insertAfter($spliter, $splitee);
while($at->nextSibling) {
$spliter->appendChild($at->nextSibling);
}
$at = $splitee; $splitee = $splitee->parentNode;
}
$this->insertAfter($node, $parent);
}
// Do nothing
else if($location == self::INLINE) {
if(in_array(strtolower($node->tagName), self::$block_level_elements)) {
user_error(
'Requested to insert block tag '.$node->tagName.
' inline - probably this will break HTML compliance',
E_USER_WARNING
);
}
// NOP
}
else {
user_error('Unknown value for $location argument '.$location, E_USER_ERROR);
}
}
/**
* Given a node with represents a shortcode marker and some information about the shortcode, call the
* shortcode handler & replace the marker with the actual content
*
* @param DOMElement $node
* @param array $tag
*/
protected function replaceMarkerWithContent($node, $tag) {
$content = $this->getShortcodeReplacementText($tag);
if ($content) {
$parsed = Injector::inst()->create('HTMLValue', $content);
$body = $parsed->getBody();
if ($body) $this->insertListAfter($body->childNodes, $node);
}
$this->removeNode($node);
}
/**
* Parse a string, and replace any registered shortcodes within it with the result of the mapped callback.
*
* @param string $content
* @return string
*/
public function parse($content) {
// If no shortcodes defined, don't try and parse any
if(!$this->shortcodes) return $content;
// If no content, don't try and parse it
if (!trim($content)) return $content;
// First we operate in text mode, replacing any shortcodes with marker elements so that later we can
// use a proper DOM
list($content, $tags) = $this->replaceElementTagsWithMarkers($content);
$htmlvalue = Injector::inst()->create('HTMLValue', $content);
// Now parse the result into a DOM
if (!$htmlvalue->isValid()){
if(self::$error_behavior == self::ERROR) {
user_error('Couldn't decode HTML when processing short codes', E_USER_ERRROR);
}
else {
return $content;
}
}
// First, replace any shortcodes that are in attributes
$this->replaceAttributeTagsWithContent($htmlvalue);
// Find all the element scoped shortcode markers
$shortcodes = $htmlvalue->query('//img[@class="'.self::$marker_class.'"]');
// Find the parents. Do this before DOM modification, since SPLIT might cause parents to move otherwise
$parents = $this->findParentsForMarkers($shortcodes);
foreach($shortcodes as $shortcode) {
$tag = $tags[$shortcode->getAttribute('data-tagid')];
$parent = $parents[$shortcode->getAttribute('data-parentid')];
$class = null;
if(!empty($tag['attrs']['location'])) $class = $tag['attrs']['location'];
else if(!empty($tag['attrs']['class'])) $class = $tag['attrs']['class'];
$location = self::INLINE;
if($class == 'left' || $class == 'right') $location = self::BEFORE;
if($class == 'center' || $class == 'leftALone') $location = self::SPLIT;
if(!$parent) {
if($location !== self::INLINE) {
user_error("Parent block for shortcode couldn't be found, but location wasn't INLINE",
E_USER_ERROR);
}
}
else {
$this->moveMarkerToCompliantHome($shortcode, $parent, $location);
}
$this->replaceMarkerWithContent($shortcode, $tag);
}
$content = $htmlvalue->getContent();
// Clean up any marker classes left over, for example, those injected into <script> tags
$parser = $this;
$content = preg_replace_callback(
// Not a general-case parser; assumes that the HTML generated in replaceElementTagsWithMarkers()
// hasn't been heavily modified
'/<img[^>]+class="'.preg_quote(self::$marker_class).'"[^>]+data-tagid="([^"]+)"[^>]+>/i',
function ($matches) use ($tags, $parser) {
$tag = $tags[$matches[1]];
return $parser->getShortcodeReplacementText($tag);
},
$content
);
return $content;
}
}