| Current Path : /var/www/html/ift/vendor/easyrdf/easyrdf/lib/EasyRdf/Serialiser/ |
Linux ift1.ift-informatik.de 5.4.0-216-generic #236-Ubuntu SMP Fri Apr 11 19:53:21 UTC 2025 x86_64 |
| Current File : /var/www/html/ift/vendor/easyrdf/easyrdf/lib/EasyRdf/Serialiser/RdfXml.php |
<?php
/**
* EasyRdf
*
* LICENSE
*
* Copyright (c) 2009-2026 Nicholas J Humfrey. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author 'Nicholas J Humfrey" may be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* @package EasyRdf
* @copyright Copyright (c) 2009-2026 Nicholas J Humfrey
* @license http://www.opensource.org/licenses/bsd-license.php
*/
/**
* Class to serialise an EasyRdf_Graph to RDF/XML
* with no external dependancies.
*
* @package EasyRdf
* @copyright Copyright (c) 2009-2026 Nicholas J Humfrey
* @license http://www.opensource.org/licenses/bsd-license.php
*/
class EasyRdf_Serialiser_RdfXml extends EasyRdf_Serialiser
{
private $outputtedResources = array();
/** A constant for the RDF Type property URI */
const RDF_XML_LITERAL = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral';
/**
* Protected method to serialise an object node into an XML object
* @ignore
*/
protected function rdfxmlObject($property, $obj, $depth)
{
$indent = str_repeat(' ', $depth);
if ($property[0] === ':') {
$property = substr($property, 1);
}
if (is_object($obj) and $obj instanceof EasyRdf_Resource) {
$pcount = count($obj->propertyUris());
$rpcount = $this->reversePropertyCount($obj);
$alreadyOutput = isset($this->outputtedResources[$obj->getUri()]);
$tag = "{$indent}<{$property}";
if ($obj->isBNode()) {
if ($alreadyOutput or $rpcount > 1 or $pcount == 0) {
$tag .= " rdf:nodeID=\"".htmlspecialchars($obj->getBNodeId()).'"';
}
} else {
if ($alreadyOutput or $rpcount != 1 or $pcount == 0) {
$tag .= " rdf:resource=\"".htmlspecialchars($obj->getURI()).'"';
}
}
if ($alreadyOutput == false and $rpcount == 1 and $pcount > 0) {
$xml = $this->rdfxmlResource($obj, false, $depth+1);
if ($xml) {
return "$tag>$xml$indent</$property>\n\n";
} else {
return '';
}
} else {
return $tag."/>\n";
}
} elseif (is_object($obj) and $obj instanceof EasyRdf_Literal) {
$atrributes = "";
$datatype = $obj->getDatatypeUri();
if ($datatype) {
if ($datatype == self::RDF_XML_LITERAL) {
$atrributes .= " rdf:parseType=\"Literal\"";
$value = strval($obj);
} else {
$datatype = htmlspecialchars($datatype);
$atrributes .= " rdf:datatype=\"$datatype\"";
}
} elseif ($obj->getLang()) {
$atrributes .= ' xml:lang="'.
htmlspecialchars($obj->getLang()).'"';
}
// Escape the value
if (!isset($value)) {
$value = htmlspecialchars(strval($obj));
}
return "{$indent}<{$property}{$atrributes}>{$value}</{$property}>\n";
} else {
throw new EasyRdf_Exception(
"Unable to serialise object to xml: ".getType($obj)
);
}
}
/**
* Protected method to serialise a whole resource and its properties
* @ignore
*/
protected function rdfxmlResource($res, $showNodeId, $depth = 1)
{
// Keep track of the resources we have already serialised
if (isset($this->outputtedResources[$res->getUri()])) {
return '';
} else {
$this->outputtedResources[$res->getUri()] = true;
}
// If the resource has no properties - don't serialise it
$properties = $res->propertyUris();
if (count($properties) == 0) {
return '';
}
$type = $res->type();
if ($type) {
$this->addPrefix($type);
} else {
$type = 'rdf:Description';
}
$indent = str_repeat(' ', $depth);
$xml = "\n$indent<$type";
if ($res->isBNode()) {
if ($showNodeId) {
$xml .= ' rdf:nodeID="'.htmlspecialchars($res->getBNodeId()).'"';
}
} else {
$xml .= ' rdf:about="'.htmlspecialchars($res->getUri()).'"';
}
$xml .= ">\n";
if ($res instanceof EasyRdf_Container) {
foreach ($res as $item) {
$xml .= $this->rdfxmlObject('rdf:li', $item, $depth+1);
}
} else {
foreach ($properties as $property) {
$short = EasyRdf_Namespace::shorten($property, true);
if ($short) {
$this->addPrefix($short);
$objects = $res->all("<$property>");
if ($short == 'rdf:type' && $type != 'rdf:Description') {
array_shift($objects);
}
foreach ($objects as $object) {
$xml .= $this->rdfxmlObject($short, $object, $depth+1);
}
} else {
throw new EasyRdf_Exception(
"It is not possible to serialse the property ".
"'$property' to RDF/XML."
);
}
}
}
$xml .= "$indent</$type>\n";
return $xml;
}
/**
* Method to serialise an EasyRdf_Graph to RDF/XML
*
* @param EasyRdf_Graph $graph An EasyRdf_Graph object.
* @param string $format The name of the format to convert to.
* @param array $options
* @throws EasyRdf_Exception
* @return string The RDF in the new desired format.
*/
public function serialise($graph, $format, array $options = array())
{
parent::checkSerialiseParams($graph, $format);
if ($format != 'rdfxml') {
throw new EasyRdf_Exception(
"EasyRdf_Serialiser_RdfXml does not support: $format"
);
}
// store of namespaces to be appended to the rdf:RDF tag
$this->prefixes = array('rdf' => true);
// store of the resource URIs we have serialised
$this->outputtedResources = array();
$xml = '';
// Serialise URIs first
foreach ($graph->resources() as $resource) {
if (!$resource->isBnode()) {
$xml .= $this->rdfxmlResource($resource, true);
}
}
// Serialise bnodes afterwards
foreach ($graph->resources() as $resource) {
if ($resource->isBnode()) {
$xml .= $this->rdfxmlResource($resource, true);
}
}
// iterate through namepsaces array prefix and output a string.
$namespaceStr = '';
foreach ($this->prefixes as $prefix => $count) {
$url = EasyRdf_Namespace::get($prefix);
if (strlen($namespaceStr)) {
$namespaceStr .= "\n ";
}
if (strlen($prefix) === 0) {
$namespaceStr .= ' xmlns="'.htmlspecialchars($url).'"';
} else {
$namespaceStr .= ' xmlns:'.$prefix.'="'.htmlspecialchars($url).'"';
}
}
return "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n".
"<rdf:RDF". $namespaceStr . ">\n" . $xml . "\n</rdf:RDF>\n";
}
}