simple-oai-pmh/oai2xml.php

121 lines
4.8 KiB
PHP

<?php
class OAI2XML {
public $doc; // DOMDocument. Handle of current XML Document object
function __construct($uri, $verb, $request_args) {
$this->verb = $verb;
$this->doc = new DOMDocument("1.0","UTF-8");
$oai_node = $this->doc->createElement("OAI-PMH");
$oai_node->setAttribute("xmlns","http://www.openarchives.org/OAI/2.0/");
$oai_node->setAttribute("xmlns:xsi","http://www.w3.org/2001/XMLSchema-instance");
$oai_node->setAttribute("xsi:schemaLocation","http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd");
$this->addChild($oai_node,"responseDate",gmdate("Y-m-d\TH:i:s\Z"));
$this->doc->appendChild($oai_node);
$request = $this->addChild($this->doc->documentElement,"request",$uri);
$request->setAttribute('verb', $this->verb);
foreach($request_args as $key => $value) {
$request->setAttribute($key,$value);
}
}
function display() {
$pr = new DOMDocument();
$pr->preserveWhiteSpace = false;
$pr->formatOutput = true;
$pr->loadXML($this->doc->saveXML());
echo $pr->saveXML();
}
/**
* Add a child node to a parent node on a XML Doc: a worker function.
*
* @param $mom_node
* Type: DOMNode. The target node.
*
* @param $name
* Type: string. The name of child nade is being added
*
* @param $value
* Type: string. Text for the adding node if it is a text node.
*
* @return DOMElement $added_node
* The newly created node, can be used for further expansion.
* If no further expansion is expected, return value can be igored.
*/
function addChild($mom_node,$name, $value='') {
$added_node = $this->doc->createElement($name,$value);
$added_node = $mom_node->appendChild($added_node);
return $added_node;
}
}
class OAI2XMLResponse extends OAI2XML {
function __construct($verb, $request_args) {
parent::__construct($verb, $request_args);
$this->verbNode = $this->addChild($this->doc->documentElement,$this->verb);
}
/**
* Add direct child nodes to verb node (OAI-PMH), e.g. response to ListMetadataFormats.
* Different verbs can have different required child nodes.
* \see create_record, create_header
*
* \param $nodeName Type: string. The name of appending node.
* \param $value Type: string. The content of appending node.
*/
function addToVerbNode($nodeName, $value=null) {
return $this->addChild($this->verbNode,$nodeName,$value);
}
/**
* Headers are enclosed inside of \<record\> to the query of ListRecords, ListIdentifiers and etc.
*
* \param $identifier Type: string. The identifier string for node \<identifier\>.
* \param $timestamp Type: timestamp. Timestapme in UTC format for node \<datastamp\>.
* \param $ands_class Type: mix. Can be an array or just a string. Content of \<setSpec\>.
* \param $add_to_node Type: DOMElement. Default value is null.
* In normal cases, $add_to_node is the \<record\> node created previously. When it is null, the newly created header node is attatched to $this->verbNode.
* Otherwise it will be attatched to the desired node defined in $add_to_node.
*/
function createHeader($identifier,$timestamp,$ands_class, $add_to_node=null) {
if(is_null($add_to_node)) {
$header_node = $this->addToVerbNode("header");
} else {
$header_node = $this->addChild($add_to_node,"header");
}
$this->addChild($header_node,"identifier",$identifier);
$this->addChild($header_node,"datestamp",$timestamp);
if (is_array($ands_class)) {
foreach ($ands_class as $setspec) {
$this->addChild($header_node,"setSpec",$setspec);
}
} else {
$this->addChild($header_node,"setSpec",$ands_class);
}
return $header_node;
}
/**
* If there are too many records request could not finished a resumpToken is generated to let harvester know
*
* \param $token Type: string. A random number created somewhere?
* \param $expirationdatetime Type: string. A string representing time.
* \param $num_rows Type: integer. Number of records retrieved.
* \param $cursor Type: string. Cursor can be used for database to retrieve next time.
*/
function createResumptionToken($token, $expirationdatetime, $num_rows, $cursor=null) {
$resump_node = $this->addChild($this->verbNode,"resumptionToken",$token);
if(isset($expirationdatetime)) {
$resump_node->setAttribute("expirationDate",$expirationdatetime);
}
$resump_node->setAttribute("completeListSize",$num_rows);
$resump_node->setAttribute("cursor",$cursor);
}
}