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<?php
/**
* This module contains the XRDS parsing code.
*
* PHP versions 4 and 5
*
* LICENSE: See the COPYING file included in this distribution.
*
* @package Yadis
* @author JanRain, Inc. <openid@janrain.com>
* @copyright 2005 Janrain, Inc.
* @license http://www.gnu.org/copyleft/lesser.html LGPL
*/
/**
* Require the XPath implementation.
*/
require_once 'Services/Yadis/XML.php';
/**
* This match mode means a given service must match ALL filters passed
* to the Services_Yadis_XRDS::services() call.
*/
define('SERVICES_YADIS_MATCH_ALL', 101);
/**
* This match mode means a given service must match ANY filters (at
* least one) passed to the Services_Yadis_XRDS::services() call.
*/
define('SERVICES_YADIS_MATCH_ANY', 102);
/**
* The priority value used for service elements with no priority
* specified.
*/
define('SERVICES_YADIS_MAX_PRIORITY', pow(2, 30));
function Services_Yadis_getNSMap()
{
return array('xrds' => 'xri://$xrds',
'xrd' => 'xri://$xrd*($v*2.0)');
}
/**
* @access private
*/
function Services_Yadis_array_scramble($arr)
{
$result = array();
while (count($arr)) {
$index = array_rand($arr, 1);
$result[] = $arr[$index];
unset($arr[$index]);
}
return $result;
}
/**
* This class represents a <Service> element in an XRDS document.
* Objects of this type are returned by
* Services_Yadis_XRDS::services() and
* Services_Yadis_Yadis::services(). Each object corresponds directly
* to a <Service> element in the XRDS and supplies a
* getElements($name) method which you should use to inspect the
* element's contents. See {@link Services_Yadis_Yadis} for more
* information on the role this class plays in Yadis discovery.
*
* @package Yadis
*/
class Services_Yadis_Service {
/**
* Creates an empty service object.
*/
function Services_Yadis_Service()
{
$this->element = null;
$this->parser = null;
}
/**
* Return the URIs in the "Type" elements, if any, of this Service
* element.
*
* @return array $type_uris An array of Type URI strings.
*/
function getTypes()
{
$t = array();
foreach ($this->getElements('xrd:Type') as $elem) {
$c = $this->parser->content($elem);
if ($c) {
$t[] = $c;
}
}
return $t;
}
/**
* Return the URIs in the "URI" elements, if any, of this Service
* element. The URIs are returned sorted in priority order.
*
* @return array $uris An array of URI strings.
*/
function getURIs()
{
$uris = array();
$last = array();
foreach ($this->getElements('xrd:URI') as $elem) {
$uri_string = $this->parser->content($elem);
$attrs = $this->parser->attributes($elem);
if ($attrs &&
array_key_exists('priority', $attrs)) {
$priority = intval($attrs['priority']);
if (!array_key_exists($priority, $uris)) {
$uris[$priority] = array();
}
$uris[$priority][] = $uri_string;
} else {
$last[] = $uri_string;
}
}
$keys = array_keys($uris);
sort($keys);
// Rebuild array of URIs.
$result = array();
foreach ($keys as $k) {
$new_uris = Services_Yadis_array_scramble($uris[$k]);
$result = array_merge($result, $new_uris);
}
$result = array_merge($result,
Services_Yadis_array_scramble($last));
return $result;
}
/**
* Returns the "priority" attribute value of this <Service>
* element, if the attribute is present. Returns null if not.
*
* @return mixed $result Null or integer, depending on whether
* this Service element has a 'priority' attribute.
*/
function getPriority()
{
$attributes = $this->parser->attributes($this->element);
if (array_key_exists('priority', $attributes)) {
return intval($attributes['priority']);
}
return null;
}
/**
* Used to get XML elements from this object's <Service> element.
*
* This is what you should use to get all custom information out
* of this element. This is used by service filter functions to
* determine whether a service element contains specific tags,
* etc. NOTE: this only considers elements which are direct
* children of the <Service> element for this object.
*
* @param string $name The name of the element to look for
* @return array $list An array of elements with the specified
* name which are direct children of the <Service> element. The
* nodes returned by this function can be passed to $this->parser
* methods (see {@link Services_Yadis_XMLParser}).
*/
function getElements($name)
{
return $this->parser->evalXPath($name, $this->element);
}
}
/**
* This class performs parsing of XRDS documents.
*
* You should not instantiate this class directly; rather, call
* parseXRDS statically:
*
* <pre> $xrds = Services_Yadis_XRDS::parseXRDS($xml_string);</pre>
*
* If the XRDS can be parsed and is valid, an instance of
* Services_Yadis_XRDS will be returned. Otherwise, null will be
* returned. This class is used by the Services_Yadis_Yadis::discover
* method.
*
* @package Yadis
*/
class Services_Yadis_XRDS {
/**
* Instantiate a Services_Yadis_XRDS object. Requires an XPath
* instance which has been used to parse a valid XRDS document.
*/
function Services_Yadis_XRDS(&$xmlParser, &$xrdNodes)
{
$this->parser =& $xmlParser;
$this->xrdNode = $xrdNodes[count($xrdNodes) - 1];
$this->allXrdNodes =& $xrdNodes;
$this->serviceList = array();
$this->_parse();
}
/**
* Parse an XML string (XRDS document) and return either a
* Services_Yadis_XRDS object or null, depending on whether the
* XRDS XML is valid.
*
* @param string $xml_string An XRDS XML string.
* @return mixed $xrds An instance of Services_Yadis_XRDS or null,
* depending on the validity of $xml_string
*/
function &parseXRDS($xml_string, $extra_ns_map = null)
{
$_null = null;
if (!$xml_string) {
return $_null;
}
$parser = Services_Yadis_getXMLParser();
$ns_map = Services_Yadis_getNSMap();
if ($extra_ns_map && is_array($extra_ns_map)) {
$ns_map = array_merge($ns_map, $extra_ns_map);
}
if (!($parser && $parser->init($xml_string, $ns_map))) {
return $_null;
}
// Try to get root element.
$root = $parser->evalXPath('/xrds:XRDS[1]');
if (!$root) {
return $_null;
}
if (is_array($root)) {
$root = $root[0];
}
$attrs = $parser->attributes($root);
if (array_key_exists('xmlns:xrd', $attrs) &&
$attrs['xmlns:xrd'] != 'xri://$xrd*($v*2.0)') {
return $_null;
} else if (array_key_exists('xmlns', $attrs) &&
preg_match('/xri/', $attrs['xmlns']) &&
$attrs['xmlns'] != 'xri://$xrd*($v*2.0)') {
return $_null;
}
// Get the last XRD node.
$xrd_nodes = $parser->evalXPath('/xrds:XRDS[1]/xrd:XRD');
if (!$xrd_nodes) {
return $_null;
}
$xrds = new Services_Yadis_XRDS($parser, $xrd_nodes);
return $xrds;
}
/**
* @access private
*/
function _addService($priority, $service)
{
$priority = intval($priority);
if (!array_key_exists($priority, $this->serviceList)) {
$this->serviceList[$priority] = array();
}
$this->serviceList[$priority][] = $service;
}
/**
* Creates the service list using nodes from the XRDS XML
* document.
*
* @access private
*/
function _parse()
{
$this->serviceList = array();
$services = $this->parser->evalXPath('xrd:Service', $this->xrdNode);
foreach ($services as $node) {
$s =& new Services_Yadis_Service();
$s->element = $node;
$s->parser =& $this->parser;
$priority = $s->getPriority();
if ($priority === null) {
$priority = SERVICES_YADIS_MAX_PRIORITY;
}
$this->_addService($priority, $s);
}
}
/**
* Returns a list of service objects which correspond to <Service>
* elements in the XRDS XML document for this object.
*
* Optionally, an array of filter callbacks may be given to limit
* the list of returned service objects. Furthermore, the default
* mode is to return all service objects which match ANY of the
* specified filters, but $filter_mode may be
* SERVICES_YADIS_MATCH_ALL if you want to be sure that the
* returned services match all the given filters. See {@link
* Services_Yadis_Yadis} for detailed usage information on filter
* functions.
*
* @param mixed $filters An array of callbacks to filter the
* returned services, or null if all services are to be returned.
* @param integer $filter_mode SERVICES_YADIS_MATCH_ALL or
* SERVICES_YADIS_MATCH_ANY, depending on whether the returned
* services should match ALL or ANY of the specified filters,
* respectively.
* @return mixed $services An array of {@link
* Services_Yadis_Service} objects if $filter_mode is a valid
* mode; null if $filter_mode is an invalid mode (i.e., not
* SERVICES_YADIS_MATCH_ANY or SERVICES_YADIS_MATCH_ALL).
*/
function services($filters = null,
$filter_mode = SERVICES_YADIS_MATCH_ANY)
{
$pri_keys = array_keys($this->serviceList);
sort($pri_keys, SORT_NUMERIC);
// If no filters are specified, return the entire service
// list, ordered by priority.
if (!$filters ||
(!is_array($filters))) {
$result = array();
foreach ($pri_keys as $pri) {
$result = array_merge($result, $this->serviceList[$pri]);
}
return $result;
}
// If a bad filter mode is specified, return null.
if (!in_array($filter_mode, array(SERVICES_YADIS_MATCH_ANY,
SERVICES_YADIS_MATCH_ALL))) {
return null;
}
// Otherwise, use the callbacks in the filter list to
// determine which services are returned.
$filtered = array();
foreach ($pri_keys as $priority_value) {
$service_obj_list = $this->serviceList[$priority_value];
foreach ($service_obj_list as $service) {
$matches = 0;
foreach ($filters as $filter) {
if (call_user_func_array($filter, array($service))) {
$matches++;
if ($filter_mode == SERVICES_YADIS_MATCH_ANY) {
$pri = $service->getPriority();
if ($pri === null) {
$pri = SERVICES_YADIS_MAX_PRIORITY;
}
if (!array_key_exists($pri, $filtered)) {
$filtered[$pri] = array();
}
$filtered[$pri][] = $service;
break;
}
}
}
if (($filter_mode == SERVICES_YADIS_MATCH_ALL) &&
($matches == count($filters))) {
$pri = $service->getPriority();
if ($pri === null) {
$pri = SERVICES_YADIS_MAX_PRIORITY;
}
if (!array_key_exists($pri, $filtered)) {
$filtered[$pri] = array();
}
$filtered[$pri][] = $service;
}
}
}
$pri_keys = array_keys($filtered);
sort($pri_keys, SORT_NUMERIC);
$result = array();
foreach ($pri_keys as $pri) {
$result = array_merge($result, $filtered[$pri]);
}
return $result;
}
}
?>