<?php
declare(strict_types=1);
namespace Sabre\Xml;
/**
* XML parsing and writing service.
*
* You are encouraged to make a instance of this for your application and
* potentially extend it, as a central API point for dealing with xml and
* configuring the reader and writer.
*
* @copyright Copyright (C) 2009-2015 fruux GmbH (https://fruux.com/).
* @author Evert Pot (http://evertpot.com/)
* @license http://sabre.io/license/ Modified BSD License
*/
class Service
{
/**
* This is the element map. It contains a list of XML elements (in clark
* notation) as keys and PHP class names as values.
*
* The PHP class names must implement Sabre\Xml\Element.
*
* Values may also be a callable. In that case the function will be called
* directly.
*
* @var array
*/
public $elementMap = [];
/**
* This is a list of namespaces that you want to give default prefixes.
*
* You must make sure you create this entire list before starting to write.
* They should be registered on the root element.
*
* @var array
*/
public $namespaceMap = [];
/**
* This is a list of custom serializers for specific classes.
*
* The writer may use this if you attempt to serialize an object with a
* class that does not implement XmlSerializable.
*
* Instead it will look at this classmap to see if there is a custom
* serializer here. This is useful if you don't want your value objects
* to be responsible for serializing themselves.
*
* The keys in this classmap need to be fully qualified PHP class names,
* the values must be callbacks. The callbacks take two arguments. The
* writer class, and the value that must be written.
*
* function (Writer $writer, object $value)
*
* @var array
*/
public $classMap = [];
/**
* A bitmask of the LIBXML_* constants.
*
* @var int
*/
public $options = 0;
/**
* Returns a fresh XML Reader.
*/
public function getReader(): Reader
{
$r = new Reader();
$r->elementMap = $this->elementMap;
return $r;
}
/**
* Returns a fresh xml writer.
*/
public function getWriter(): Writer
{
$w = new Writer();
$w->namespaceMap = $this->namespaceMap;
$w->classMap = $this->classMap;
return $w;
}
/**
* Parses a document in full.
*
* Input may be specified as a string or readable stream resource.
* The returned value is the value of the root document.
*
* Specifying the $contextUri allows the parser to figure out what the URI
* of the document was. This allows relative URIs within the document to be
* expanded easily.
*
* The $rootElementName is specified by reference and will be populated
* with the root element name of the document.
*
* @param string|resource $input
*
* @throws ParseException
*
* @return array|object|string
*/
public function parse($input, string $contextUri = null, string &$rootElementName = null)
{
if (is_resource($input)) {
// Unfortunately the XMLReader doesn't support streams. When it
// does, we can optimize this.
$input = (string) stream_get_contents($input);
}
// If input is empty, then its safe to throw exception
if (empty($input)) {
throw new ParseException('The input element to parse is empty. Do not attempt to parse');
}
$r = $this->getReader();
$r->contextUri = $contextUri;
$r->XML($input, null, $this->options);
$result = $r->parse();
$rootElementName = $result['name'];
return $result['value'];
}
/**
* Parses a document in full, and specify what the expected root element
* name is.
*
* This function works similar to parse, but the difference is that the
* user can specify what the expected name of the root element should be,
* in clark notation.
*
* This is useful in cases where you expected a specific document to be
* passed, and reduces the amount of if statements.
*
* It's also possible to pass an array of expected rootElements if your
* code may expect more than one document type.
*
* @param string|string[] $rootElementName
* @param string|resource $input
*
* @throws ParseException
*
* @return array|object|string
*/
public function expect($rootElementName, $input, string $contextUri = null)
{
if (is_resource($input)) {
// Unfortunately the XMLReader doesn't support streams. When it
// does, we can optimize this.
$input = (string) stream_get_contents($input);
}
// If input is empty, then its safe to throw exception
if (empty($input)) {
throw new ParseException('The input element to parse is empty. Do not attempt to parse');
}
$r = $this->getReader();
$r->contextUri = $contextUri;
$r->XML($input, null, $this->options);
$rootElementName = (array) $rootElementName;
foreach ($rootElementName as &$rEl) {
if ('{' !== $rEl[0]) {
$rEl = '{}'.$rEl;
}
}
$result = $r->parse();
if (!in_array($result['name'], $rootElementName, true)) {
throw new ParseException('Expected '.implode(' or ', $rootElementName).' but received '.$result['name'].' as the root element');
}
return $result['value'];
}
/**
* Generates an XML document in one go.
*
* The $rootElement must be specified in clark notation.
* The value must be a string, an array or an object implementing
* XmlSerializable. Basically, anything that's supported by the Writer
* object.
*
* $contextUri can be used to specify a sort of 'root' of the PHP application,
* in case the xml document is used as a http response.
*
* This allows an implementor to easily create URI's relative to the root
* of the domain.
*
* @param string|array|object|XmlSerializable $value
*
* @return string
*/
public function write(string $rootElementName, $value, string $contextUri = null)
{
$w = $this->getWriter();
$w->openMemory();
$w->contextUri = $contextUri;
$w->setIndent(true);
$w->startDocument();
$w->writeElement($rootElementName, $value);
return $w->outputMemory();
}
/**
* Map an xml element to a PHP class.
*
* Calling this function will automatically setup the Reader and Writer
* classes to turn a specific XML element to a PHP class.
*
* For example, given a class such as :
*
* class Author {
* public $firstName;
* public $lastName;
* }
*
* and an XML element such as:
*
* <author xmlns="http://example.org/ns">
* <firstName>...</firstName>
* <lastName>...</lastName>
* </author>
*
* These can easily be mapped by calling:
*
* $service->mapValueObject('{http://example.org}author', 'Author');
*/
public function mapValueObject(string $elementName, string $className)
{
list($namespace) = self::parseClarkNotation($elementName);
$this->elementMap[$elementName] = function (Reader $reader) use ($className, $namespace) {
return \Sabre\Xml\Deserializer\valueObject($reader, $className, $namespace);
};
$this->classMap[$className] = function (Writer $writer, $valueObject) use ($namespace) {
return \Sabre\Xml\Serializer\valueObject($writer, $valueObject, $namespace);
};
$this->valueObjectMap[$className] = $elementName;
}
/**
* Writes a value object.
*
* This function largely behaves similar to write(), except that it's
* intended specifically to serialize a Value Object into an XML document.
*
* The ValueObject must have been previously registered using
* mapValueObject().
*
* @param object $object
*
* @throws \InvalidArgumentException
*/
public function writeValueObject($object, string $contextUri = null)
{
if (!isset($this->valueObjectMap[get_class($object)])) {
throw new \InvalidArgumentException('"'.get_class($object).'" is not a registered value object class. Register your class with mapValueObject.');
}
return $this->write(
$this->valueObjectMap[get_class($object)],
$object,
$contextUri
);
}
/**
* Parses a clark-notation string, and returns the namespace and element
* name components.
*
* If the string was invalid, it will throw an InvalidArgumentException.
*
* @throws \InvalidArgumentException
*/
public static function parseClarkNotation(string $str): array
{
static $cache = [];
if (!isset($cache[$str])) {
if (!preg_match('/^{([^}]*)}(.*)$/', $str, $matches)) {
throw new \InvalidArgumentException('\''.$str.'\' is not a valid clark-notation formatted string');
}
$cache[$str] = [
$matches[1],
$matches[2],
];
}
return $cache[$str];
}
/**
* A list of classes and which XML elements they map to.
*/
protected $valueObjectMap = [];
}
