gnu-social/plugins/OStatus/extlib/XML/Feed/Parser/Atom.php

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<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
/**
* Atom feed class for XML_Feed_Parser
*
* PHP versions 5
*
* LICENSE: This source file is subject to version 3.0 of the PHP license
* that is available through the world-wide-web at the following URI:
* http://www.php.net/license/3_0.txt. If you did not receive a copy of
* the PHP License and are unable to obtain it through the web, please
* send a note to license@php.net so we can mail you a copy immediately.
*
* @category XML
* @package XML_Feed_Parser
* @author James Stewart <james@jystewart.net>
* @copyright 2005 James Stewart <james@jystewart.net>
* @license http://www.gnu.org/copyleft/lesser.html GNU LGPL 2.1
* @version CVS: $Id: Atom.php,v 1.29 2008/03/30 22:00:36 jystewart Exp $
* @link http://pear.php.net/package/XML_Feed_Parser/
*/
/**
* This is the class that determines how we manage Atom 1.0 feeds
*
* How we deal with constructs:
* date - return as unix datetime for use with the 'date' function unless specified otherwise
* text - return as is. optional parameter will give access to attributes
* person - defaults to name, but parameter based access
*
* @author James Stewart <james@jystewart.net>
* @version Release: 1.0.3
* @package XML_Feed_Parser
*/
class XML_Feed_Parser_Atom extends XML_Feed_Parser_Type
{
/**
* The URI of the RelaxNG schema used to (optionally) validate the feed
* @var string
*/
private $relax = 'atom.rnc';
/**
* We're likely to use XPath, so let's keep it global
* @var DOMXPath
*/
public $xpath;
/**
* When performing XPath queries we will use this prefix
* @var string
*/
private $xpathPrefix = '//';
/**
* The feed type we are parsing
* @var string
*/
public $version = 'Atom 1.0';
/**
* The class used to represent individual items
* @var string
*/
protected $itemClass = 'XML_Feed_Parser_AtomElement';
/**
* The element containing entries
* @var string
*/
protected $itemElement = 'entry';
/**
* Here we map those elements we're not going to handle individually
* to the constructs they are. The optional second parameter in the array
* tells the parser whether to 'fall back' (not apt. at the feed level) or
* fail if the element is missing. If the parameter is not set, the function
* will simply return false and leave it to the client to decide what to do.
* @var array
*/
protected $map = array(
'author' => array('Person'),
'contributor' => array('Person'),
'icon' => array('Text'),
'logo' => array('Text'),
'id' => array('Text', 'fail'),
'rights' => array('Text'),
'subtitle' => array('Text'),
'title' => array('Text', 'fail'),
'updated' => array('Date', 'fail'),
'link' => array('Link'),
'generator' => array('Text'),
'category' => array('Category'));
/**
* Here we provide a few mappings for those very special circumstances in
* which it makes sense to map back to the RSS2 spec. Key is RSS2 version
* value is an array consisting of the equivalent in atom and any attributes
* needed to make the mapping.
* @var array
*/
protected $compatMap = array(
'guid' => array('id'),
'links' => array('link'),
'tags' => array('category'),
'contributors' => array('contributor'));
/**
* Our constructor does nothing more than its parent.
*
* @param DOMDocument $xml A DOM object representing the feed
* @param bool (optional) $string Whether or not to validate this feed
*/
function __construct(DOMDocument $model, $strict = false)
{
$this->model = $model;
if ($strict) {
if (! $this->model->relaxNGValidateSource($this->relax)) {
throw new XML_Feed_Parser_Exception('Failed required validation');
}
}
$this->xpath = new DOMXPath($this->model);
$this->xpath->registerNamespace('atom', 'http://www.w3.org/2005/Atom');
$this->numberEntries = $this->count('entry');
}
/**
* Implement retrieval of an entry based on its ID for atom feeds.
*
* This function uses XPath to get the entry based on its ID. If DOMXPath::evaluate
* is available, we also use that to store a reference to the entry in the array
* used by getEntryByOffset so that method does not have to seek out the entry
* if it's requested that way.
*
* @param string $id any valid Atom ID.
* @return XML_Feed_Parser_AtomElement
*/
function getEntryById($id)
{
if (isset($this->idMappings[$id])) {
return $this->entries[$this->idMappings[$id]];
}
$entries = $this->xpath->query("//atom:entry[atom:id='$id']");
if ($entries->length > 0) {
$xmlBase = $entries->item(0)->baseURI;
$entry = new $this->itemClass($entries->item(0), $this, $xmlBase);
if (in_array('evaluate', get_class_methods($this->xpath))) {
$offset = $this->xpath->evaluate("count(preceding-sibling::atom:entry)", $entries->item(0));
$this->entries[$offset] = $entry;
}
$this->idMappings[$id] = $entry;
return $entry;
}
}
/**
* Retrieves data from a person construct.
*
* Get a person construct. We default to the 'name' element but allow
* access to any of the elements.
*
* @param string $method The name of the person construct we want
* @param array $arguments An array which we hope gives a 'param'
* @return string|false
*/
protected function getPerson($method, $arguments)
{
$offset = empty($arguments[0]) ? 0 : $arguments[0];
$parameter = empty($arguments[1]['param']) ? 'name' : $arguments[1]['param'];
$section = $this->model->getElementsByTagName($method);
if ($parameter == 'url') {
$parameter = 'uri';
}
if ($section->length <= $offset) {
return false;
}
$param = $section->item($offset)->getElementsByTagName($parameter);
if ($param->length == 0) {
return false;
}
return $param->item(0)->nodeValue;
}
/**
* Retrieves an element's content where that content is a text construct.
*
* Get a text construct. When calling this method, the two arguments
* allowed are 'offset' and 'attribute', so $parser->subtitle() would
* return the content of the element, while $parser->subtitle(false, 'type')
* would return the value of the type attribute.
*
* @todo Clarify overlap with getContent()
* @param string $method The name of the text construct we want
* @param array $arguments An array which we hope gives a 'param'
* @return string
*/
protected function getText($method, $arguments)
{
$offset = empty($arguments[0]) ? 0: $arguments[0];
$attribute = empty($arguments[1]) ? false : $arguments[1];
$tags = $this->model->getElementsByTagName($method);
if ($tags->length <= $offset) {
return false;
}
$content = $tags->item($offset);
if (! $content->hasAttribute('type')) {
$content->setAttribute('type', 'text');
}
$type = $content->getAttribute('type');
if (! empty($attribute) and
! ($method == 'generator' and $attribute == 'name')) {
if ($content->hasAttribute($attribute)) {
return $content->getAttribute($attribute);
} else if ($attribute == 'href' and $content->hasAttribute('uri')) {
return $content->getAttribute('uri');
}
return false;
}
return $this->parseTextConstruct($content);
}
/**
* Extract content appropriately from atom text constructs
*
* Because of different rules applied to the content element and other text
* constructs, they are deployed as separate functions, but they share quite
* a bit of processing. This method performs the core common process, which is
* to apply the rules for different mime types in order to extract the content.
*
* @param DOMNode $content the text construct node to be parsed
* @return String
* @author James Stewart
**/
protected function parseTextConstruct(DOMNode $content)
{
if ($content->hasAttribute('type')) {
$type = $content->getAttribute('type');
} else {
$type = 'text';
}
if (strpos($type, 'text/') === 0) {
$type = 'text';
}
switch ($type) {
case 'text':
case 'html':
return $content->textContent;
break;
case 'xhtml':
$container = $content->getElementsByTagName('div');
if ($container->length == 0) {
return false;
}
$contents = $container->item(0);
if ($contents->hasChildNodes()) {
/* Iterate through, applying xml:base and store the result */
$result = '';
foreach ($contents->childNodes as $node) {
$result .= $this->traverseNode($node);
}
return $result;
}
break;
case preg_match('@^[a-zA-Z]+/[a-zA-Z+]*xml@i', $type) > 0:
return $content;
break;
case 'application/octet-stream':
default:
return base64_decode(trim($content->nodeValue));
break;
}
return false;
}
/**
* Get a category from the entry.
*
* A feed or entry can have any number of categories. A category can have the
* attributes term, scheme and label.
*
* @param string $method The name of the text construct we want
* @param array $arguments An array which we hope gives a 'param'
* @return string
*/
function getCategory($method, $arguments)
{
$offset = empty($arguments[0]) ? 0: $arguments[0];
$attribute = empty($arguments[1]) ? 'term' : $arguments[1];
$categories = $this->model->getElementsByTagName('category');
if ($categories->length <= $offset) {
$category = $categories->item($offset);
if ($category->hasAttribute($attribute)) {
return $category->getAttribute($attribute);
}
}
return false;
}
/**
* This element must be present at least once with rel="feed". This element may be
* present any number of further times so long as there is no clash. If no 'rel' is
* present and we're asked for one, we follow the example of the Universal Feed
* Parser and presume 'alternate'.
*
* @param int $offset the position of the link within the container
* @param string $attribute the attribute name required
* @param array an array of attributes to search by
* @return string the value of the attribute
*/
function getLink($offset = 0, $attribute = 'href', $params = false)
{
if (is_array($params) and !empty($params)) {
$terms = array();
$alt_predicate = '';
$other_predicate = '';
foreach ($params as $key => $value) {
if ($key == 'rel' && $value == 'alternate') {
$alt_predicate = '[not(@rel) or @rel="alternate"]';
} else {
$terms[] = "@$key='$value'";
}
}
if (!empty($terms)) {
$other_predicate = '[' . join(' and ', $terms) . ']';
}
$query = $this->xpathPrefix . 'atom:link' . $alt_predicate . $other_predicate;
$links = $this->xpath->query($query);
} else {
$links = $this->model->getElementsByTagName('link');
}
if ($links->length > $offset) {
if ($links->item($offset)->hasAttribute($attribute)) {
$value = $links->item($offset)->getAttribute($attribute);
if ($attribute == 'href') {
$value = $this->addBase($value, $links->item($offset));
}
return $value;
} else if ($attribute == 'rel') {
return 'alternate';
}
}
return false;
}
}
?>