/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, 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 end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Apache Cocoon" and "Apache Software Foundation" must not be
used to endorse or promote products derived from this software without
prior written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, 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.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
Stefano Mazzocchi <stefano@apache.org>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.cocoon.transformation;
import org.apache.avalon.framework.activity.Initializable;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.ResourceNotFoundException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.util.TraxErrorHandler;
import org.apache.excalibur.source.SourceValidity;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import org.xmldb.api.DatabaseManager;
import org.xmldb.api.base.Collection;
import org.xmldb.api.base.Database;
import org.xmldb.api.base.Resource;
import org.xmldb.api.base.XMLDBException;
import org.xmldb.api.modules.XUpdateQueryService;
import java.io.IOException;
import java.io.Serializable;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.stream.StreamResult;
/**
* This transformer allows to perform resource creation, deletion, and
* XUpdate command execution in XML:DB.
*
* <p>Definition:</p>
* <pre>
* <map:transformer name="xmldb" src="org.apache.cocoon.transformation.XMLDBTransformer">
* <driver>org.apache.xindice.client.xmldb.DatabaseImpl</driver>
* <base>xmldb:xindice:///db/collection</base>
* </map:transformer>
* </pre>
*
* <p>Invokation:</p>
* <pre>
* <map:transform type="xmldb">
* <map:parameter name="base" value="xmldb:xindice:///db/collection"/>
* </map:transform>
* </pre>
*
* <p>Input XML document example:</p>
* <pre>
* <page xmlns:xindice="http://apache.org/cocoon/xmldb/1.0">
* ...
* <xindice:query type="create" oid="xmldb-object-id">
* <page>
* XML Object body
* </page>
* </xindice:query>
*
* <xindice:query type="delete" oid="xmldb-object-id"/>
*
* <xindice:query type="update" oid="xmldb-object-id">
* <xu:modifications version="1.0" xmlns:xu="http://www.xmldb.org/xupdate">
* <xu:remove select="/person/phone[@type = 'home']"/>
* <xu:update select="/person/phone[@type = 'work']">
* 480-300-3003
* </xu:update>
* </xu:modifications>
* </xindice:query>
* ...
* </page>
* </pre>
*
* <p>Output XML document example:</p>
* <pre>
* <page xmlns:xindice="http://apache.org/cocoon/xmldb/1.0">
* ...
* <xindice:query type="create" oid="xmldb-object-id" result="success"/>
*
* <xindice:query type="delete" oid="xmldb-object-id" result="success"/>
*
* <xindice:query type="update" oid="xmldb-object-id" result="failure">
* Resource xmldb-object-id is not found
* </xindice:query>
* ...
* </page>
* </pre>
*
* <p>Known bugs and limitations:</p>
* <ul>
* <li>No namespaces with Xalan (see AbstractTextSerializer)</li>
* </ul>
*
* @author <a href="mailto:vgritsenko@apache.org">Vadim Gritsenko</a>
* @version CVS $Id: XMLDBTransformer.java,v 1.6 2003/09/09 18:52:32 joerg Exp $
*/
public class XMLDBTransformer extends AbstractTransformer
implements CacheableProcessingComponent, Configurable, Initializable {
private static String XMLDB_URI = "http://apache.org/cocoon/xmldb/1.0";
private static String XMLDB_QUERY_ELEMENT = "query";
private static String XMLDB_QUERY_TYPE_ATTRIBUTE = "type";
private static String XMLDB_QUERY_OID_ATTRIBUTE = "oid";
private static String XMLDB_QUERY_RESULT_ATTRIBUTE = "result";
/** The trax <code>TransformerFactory</code> used by this transformer. */
private SAXTransformerFactory tfactory = null;
private Properties format = new Properties();
/** The map of namespace prefixes. */
private Map prefixMap = new HashMap();
/** XML:DB driver class name. */
private String driver = null;
/** Default collection name. */
private String default_base = null;
/** Current collection name. */
private String base = null;
/** Current collection. */
private Collection collection;
/** Operation. One of: create, delete, update. */
private String operation;
/** Document ID. Can be null if update is performed on collection. */
private String key;
private StringWriter queryWriter;
private TransformerHandler queryHandler;
/** True when inside <query> element. */
private boolean processing;
public XMLDBTransformer() {
format.put(OutputKeys.ENCODING, "utf-8");
format.put(OutputKeys.INDENT, "no");
format.put(OutputKeys.OMIT_XML_DECLARATION, "yes");
}
public void configure(Configuration configuration) throws ConfigurationException {
Configuration driver = configuration.getChild("driver");
if (driver == null || driver.getValue() == null)
throw new ConfigurationException("Required driver parameter is missing.");
this.driver = driver.getValue();
Configuration default_base = configuration.getChild("base");
if (default_base != null)
this.default_base = default_base.getValue();
}
/**
* Initializes XML:DB database instance using specified driver class.
*/
public void initialize() throws Exception {
Class c = Class.forName(driver);
Database database = (Database)c.newInstance();
DatabaseManager.registerDatabase(database);
}
/** Setup the transformer. */
public void setup(SourceResolver resolver, Map objectModel, String src, Parameters par)
throws ProcessingException, SAXException, IOException {
this.base = par.getParameter("base", this.default_base);
if (this.base == null)
throw new ProcessingException("Required base parameter is missing. Syntax is: xmldb:xindice:///db/collection");
try {
this.collection = DatabaseManager.getCollection(base);
} catch (XMLDBException e) {
throw new ProcessingException("Could not get collection " + base + ": " + e.errorCode, e);
}
if(this.collection == null)
throw new ResourceNotFoundException("Collection " + base + " does not exist");
}
/**
* Helper for TransformerFactory.
*/
protected SAXTransformerFactory getTransformerFactory()
{
if(tfactory == null) {
tfactory = (SAXTransformerFactory) TransformerFactory.newInstance();
tfactory.setErrorListener(new TraxErrorHandler(getLogger()));
}
return tfactory;
}
/**
* Generate the unique key.
* This key must be unique inside the space of this component.
* This method must be invoked before the generateValidity() method.
*
* @return The generated key or <code>null</code> if the component
* is currently not cacheable.
*/
public Serializable getKey() {
return null;
}
/**
* Generate the validity object.
* Before this method can be invoked the generateKey() method
* must be invoked.
*
* @return The generated validity object or <code>null</code> if the
* component is currently not cacheable.
*/
public SourceValidity getValidity() {
return null;
}
/**
* Receive notification of the beginning of a document.
*/
public void startDocument() throws SAXException {
super.startDocument();
}
/**
* Receive notification of the end of a document.
*/
public void endDocument() throws SAXException {
super.endDocument();
}
/**
* Begin the scope of a prefix-URI Namespace mapping.
*
* @param prefix The Namespace prefix being declared.
* @param uri The Namespace URI the prefix is mapped to.
*/
public void startPrefixMapping(String prefix, String uri) throws SAXException {
if (!processing) {
super.startPrefixMapping(prefix,uri);
prefixMap.put(prefix,uri);
} else if (this.queryHandler != null){
this.queryHandler.startPrefixMapping(prefix, uri);
}
}
/**
* End the scope of a prefix-URI mapping.
*
* @param prefix The prefix that was being mapping.
*/
public void endPrefixMapping(String prefix) throws SAXException {
if (!processing) {
super.endPrefixMapping(prefix);
prefixMap.remove(prefix);
} else if (this.queryHandler != null){
this.queryHandler.endPrefixMapping(prefix);
}
}
/**
* Receive notification of the beginning of an element.
*
* @param uri The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace
* processing is not being performed.
* @param loc The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty string if
* raw names are not available.
* @param a The attributes attached to the element. If there are no
* attributes, it shall be an empty Attributes object.
*/
public void startElement(String uri, String loc, String raw, Attributes a)
throws SAXException {
if (!processing) {
if (XMLDB_URI.equals(uri) && XMLDB_QUERY_ELEMENT.equals(loc)){
this.operation = a.getValue(XMLDB_QUERY_TYPE_ATTRIBUTE);
if(!"create".equals(operation) && !"delete".equals(operation) && !"update".equals(operation)) {
throw new SAXException("Supported operation types are: create, delete");
}
this.key = a.getValue(XMLDB_QUERY_OID_ATTRIBUTE);
if(!"update".equals(operation) && this.key == null) {
throw new SAXException("Object ID is missing in xmldb element");
}
processing = true;
if (!"delete".equals(operation)) {
// Prepare SAX query writer
queryWriter = new StringWriter(256);
try {
this.queryHandler = getTransformerFactory().newTransformerHandler();
this.queryHandler.setResult(new StreamResult(queryWriter));
this.queryHandler.getTransformer().setOutputProperties(format);
} catch (TransformerConfigurationException e) {
throw new SAXException("Failed to get transformer handler", e);
}
// Start query document
this.queryHandler.startDocument();
Iterator itt = prefixMap.entrySet().iterator();
while ( itt.hasNext() ) {
Map.Entry entry = (Map.Entry)itt.next();
this.queryHandler.startPrefixMapping((String)entry.getKey(), (String)entry.getValue());
}
}
} else {
super.startElement(uri,loc,raw,a);
}
} else if (this.queryHandler != null){
this.queryHandler.startElement(uri,loc,raw,a);
}
}
/**
* Receive notification of the end of an element.
*
* @param uri The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace
* processing is not being performed.
* @param loc The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty string if
* raw names are not available.
*/
public void endElement(String uri, String loc, String raw)
throws SAXException {
if (!processing) {
super.endElement(uri,loc,raw);
} else {
if (XMLDB_URI.equals(uri) && XMLDB_QUERY_ELEMENT.equals(loc)){
processing = false;
String document = null;
if (this.queryHandler != null){
// Finish building query. Remove existing prefix mappings.
Iterator itt = prefixMap.entrySet().iterator();
while ( itt.hasNext() ) {
Map.Entry entry = (Map.Entry) itt.next();
this.queryHandler.endPrefixMapping((String)entry.getKey());
}
this.queryHandler.endDocument();
document = this.queryWriter.toString();
}
// Perform operation
String result = "failure";
String message = null;
if("create".equals(operation)) {
try {
Resource resource = collection.createResource(key, "XMLResource");
resource.setContent(document);
collection.storeResource(resource);
result = "success";
key = resource.getId();
} catch (XMLDBException e) {
message = "Failed to create resource " + key + ": " + e.errorCode;
getLogger().debug(message, e);
}
} else if("delete".equals(operation)) {
try {
Resource resource = collection.getResource(this.key);
if (resource == null) {
message = "Resource " + this.key + " does not exist";
getLogger().debug(message);
} else {
collection.removeResource(resource);
result = "success";
}
} catch (XMLDBException e) {
message = "Failed to delete resource " + key + ": " + e.errorCode;
getLogger().debug(message, e);
}
} else if("update".equals(operation)) {
try {
XUpdateQueryService service =
(XUpdateQueryService) collection.getService("XUpdateQueryService", "1.0");
long count = (this.key == null)?
service.update(document) : service.updateResource(this.key, document);
message = count + " entries updated.";
result = "success";
} catch (XMLDBException e) {
message = "Failed to update resource " + key + ": " + e.errorCode;
getLogger().debug(message, e);
}
}
// Report result
AttributesImpl attrs = new AttributesImpl();
attrs.addAttribute(null, XMLDB_QUERY_OID_ATTRIBUTE,
XMLDB_QUERY_OID_ATTRIBUTE, "CDATA", this.key);
attrs.addAttribute(null, XMLDB_QUERY_TYPE_ATTRIBUTE,
XMLDB_QUERY_TYPE_ATTRIBUTE, "CDATA", this.operation);
attrs.addAttribute(null, XMLDB_QUERY_RESULT_ATTRIBUTE,
XMLDB_QUERY_RESULT_ATTRIBUTE, "CDATA", result);
super.startElement(uri, loc, raw, attrs);
if (message != null) {
super.characters(message.toCharArray(), 0, message.length());
}
super.endElement(uri, loc, raw);
} else if (this.queryHandler != null){
this.queryHandler.endElement(uri, loc, raw);
}
}
}
/**
* Receive notification of character data.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*/
public void characters(char c[], int start, int len) throws SAXException {
if (!processing) {
super.characters(c,start,len);
} else if (this.queryHandler != null){
this.queryHandler.characters(c,start,len);
}
}
/**
* Receive notification of ignorable whitespace in element content.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*/
public void ignorableWhitespace(char c[], int start, int len) throws SAXException {
if (!processing) {
super.ignorableWhitespace(c,start,len);
} else if (this.queryHandler != null){
this.queryHandler.ignorableWhitespace(c,start,len);
}
}
/**
* Receive notification of a processing instruction.
*
* @param target The processing instruction target.
* @param data The processing instruction data, or null if none was
* supplied.
*/
public void processingInstruction(String target, String data) throws SAXException {
if (!processing) {
super.processingInstruction(target,data);
} else if (this.queryHandler != null){
this.queryHandler.processingInstruction(target,data);
}
}
/**
* Receive notification of a skipped entity.
*
* @param name The name of the skipped entity. If it is a parameter
* entity, the name will begin with '%'.
*/
public void skippedEntity(String name) throws SAXException {
if (!processing) {
super.skippedEntity(name);
} else if (this.queryHandler != null){
this.queryHandler.skippedEntity(name);
}
}
/**
* Report the start of DTD declarations, if any.
*
* @param name The document type name.
* @param publicId The declared public identifier for the external DTD
* subset, or null if none was declared.
* @param systemId The declared system identifier for the external DTD
* subset, or null if none was declared.
*/
public void startDTD(String name, String publicId, String systemId) throws SAXException {
if (!processing) {
super.startDTD(name,publicId,systemId);
} else {
throw new SAXException(
"Recieved startDTD after beginning SVG extraction process."
);
}
}
/**
* Report the end of DTD declarations.
*/
public void endDTD() throws SAXException {
if (!processing) {
super.endDTD();
} else {
throw new SAXException("Recieved endDTD after xmldb element.");
}
}
/**
* Report the beginning of an entity.
*
* @param name The name of the entity. If it is a parameter entity, the
* name will begin with '%'.
*/
public void startEntity(String name) throws SAXException {
if (!processing) {
super.startEntity(name);
} else if (this.queryHandler != null){
this.queryHandler.startEntity(name);
}
}
/**
* Report the end of an entity.
*
* @param name The name of the entity that is ending.
*/
public void endEntity(String name) throws SAXException {
if (!processing) {
super.endEntity(name);
} else if (this.queryHandler != null){
this.queryHandler.endEntity(name);
}
}
/**
* Report the start of a CDATA section.
*/
public void startCDATA() throws SAXException {
if (!processing) {
super.startCDATA();
} else if (this.queryHandler != null){
this.queryHandler.startCDATA();
}
}
/**
* Report the end of a CDATA section.
*/
public void endCDATA() throws SAXException {
if (!processing) {
super.endCDATA();
} else if (this.queryHandler != null){
this.queryHandler.endCDATA();
}
}
/**
* Report an XML comment anywhere in the document.
*
* @param ch An array holding the characters in the comment.
* @param start The starting position in the array.
* @param len The number of characters to use from the array.
*/
public void comment(char ch[], int start, int len) throws SAXException {
if (!processing) {
super.comment(ch,start,len);
} else if (this.queryHandler != null){
this.queryHandler.comment(ch,start,len);
}
}
public void recycle() {
this.prefixMap.clear();
this.queryHandler = null;
this.queryWriter = null;
try {
if (collection != null) collection.close();
} catch (XMLDBException e) {
getLogger().error("Failed to close collection " + base + ". Error " + e.errorCode, e);
}
collection = null;
super.recycle();
}
}