/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.sling.scripting.xproc.cocoon.transform;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TemplatesHandler;
import javax.xml.transform.sax.TransformerHandler;
import org.apache.cocoon.pipeline.component.sax.AbstractTransformer;
import org.apache.cocoon.pipeline.component.sax.XMLConsumer;
import org.apache.cocoon.pipeline.component.sax.XMLConsumerAdapter;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.scripting.SlingScriptHelper;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.XMLReaderFactory;
/**
* A Cocoon transformer that executes XSLT
* transformations. The templates are Sling
* resources supporting to be adapted to
* {@link InputStream}.
*/
public class SlingTransformer extends AbstractTransformer {
private SlingHttpServletRequest request;
private Map<String, Object> parameters;
private String srcAbsPath;
public SlingTransformer() {
super();
}
public SlingTransformer(SlingScriptHelper sling, String srcAbsPath) {
this(sling, srcAbsPath, null);
}
public SlingTransformer(SlingScriptHelper sling, String srcAbsPath, Map<String, Object> parameters) {
super();
if (srcAbsPath == null) {
throw new IllegalArgumentException("The parameter 'source' mustn't be null.");
}
this.request = sling.getRequest();
this.parameters = parameters;
this.srcAbsPath = srcAbsPath;
}
/**
* Test if the name is a valid parameter name for XSLT
*/
private static boolean isValidXSLTParameterName(String name) {
return name.matches("[a-zA-Z_][\\w\\-\\.]*");
}
@Override
public void setConfiguration(Map<String, ? extends Object> configuration) {
this.parameters = new HashMap<String, Object>(configuration);
}
@Override
protected void setXMLConsumer(XMLConsumer consumer) {
TransformerHandler transformerHandler;
try {
transformerHandler = this.createTransformerHandler();
} catch (Exception ex) {
throw new RuntimeException("Could not initialize transformer handler.", ex);
}
final Map<String, Object> map = this.getLogicSheetParameters();
if (map != null) {
final Transformer transformer = transformerHandler.getTransformer();
for (Entry<String, Object> entry : map.entrySet()) {
transformer.setParameter(entry.getKey(), entry.getValue());
}
}
final SAXResult result = new SAXResult();
result.setHandler(consumer);
// According to TrAX specs, all TransformerHandlers are LexicalHandlers
result.setLexicalHandler(consumer);
transformerHandler.setResult(result);
super.setXMLConsumer(new XMLConsumerAdapter(transformerHandler, transformerHandler));
}
private TransformerHandler createTransformerHandler() throws Exception {
SAXTransformerFactory transformerFactory = (SAXTransformerFactory) TransformerFactory.newInstance();
TemplatesHandler templatesHandler = transformerFactory.newTemplatesHandler();
XMLReader xmlReader = XMLReaderFactory.createXMLReader();
xmlReader.setContentHandler(templatesHandler);
InputSource inputSource = new InputSource(getXsltSource());
xmlReader.parse(inputSource);
// Create transformer handler
final TransformerHandler handler = transformerFactory.newTransformerHandler(templatesHandler.getTemplates());
return handler;
}
private Map<String, Object> getLogicSheetParameters() {
if (this.parameters == null) {
return null;
}
Map<String, Object> result = new HashMap<String, Object>();
for (Entry<String, Object> entry : this.parameters.entrySet()) {
String name = entry.getKey();
if (isValidXSLTParameterName(name)) {
result.put(name, entry.getValue());
}
}
return result;
}
/**
* Get the XSLT source. For the time being, the
* path must be absolute.
*/
private InputStream getXsltSource() throws Exception {
// The source is a xml file
Resource xmlResource = this.request.getResourceResolver().resolve(srcAbsPath);
InputStream xmlSourceFile = xmlResource.adaptTo(InputStream.class);
if (xmlSourceFile != null)
return xmlSourceFile;
return null;
}
}