/*
* eXist Apache FOP Transformation Extension
* Copyright (C) 2007 Craig Goodyer at the University of the West of England
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id$
*/
package org.exist.xquery.modules.xslfo;
import java.io.ByteArrayInputStream;
import java.util.Properties;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.modules.ModuleUtils;
import org.exist.xquery.value.Base64BinaryValueType;
import org.exist.xquery.value.BinaryValueFromInputStream;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
/**
* @author Craig Goodyer <craiggoodyer@gmail.com>
* @author Adam Retter <adam@exist-db.org>
*/
public class RenderFunction extends BasicFunction {
@SuppressWarnings("unused")
private static final Logger logger = Logger.getLogger(RenderFunction.class);
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("render", XSLFOModule.NAMESPACE_URI, XSLFOModule.PREFIX),
"Renders a given FO document. "
+ "Returns an xs:base64binary of the result. "
+ "Parameters are specified with the structure: "
+ "<parameters><param name=\"param-name1\" value=\"param-value1\"/>"
+ "</parameters>. "
+ "Recognised rendering parameters are: author, title, keywords and dpi.",
new SequenceType[]{
new FunctionParameterSequenceType("document", Type.NODE, Cardinality.EXACTLY_ONE, "FO document"),
new FunctionParameterSequenceType("mime-type", Type.STRING, Cardinality.EXACTLY_ONE, ""),
new FunctionParameterSequenceType("parameters", Type.NODE, Cardinality.ZERO_OR_ONE, "parameters for the transform")
},
new FunctionParameterSequenceType("result", Type.BASE64_BINARY, Cardinality.ZERO_OR_ONE, "result")
),
new FunctionSignature(
new QName("render", XSLFOModule.NAMESPACE_URI, XSLFOModule.PREFIX),
"Renders a given FO document. "
+ "Returns an xs:base64binary of the result. "
+ "Parameters are specified with the structure: "
+ "<parameters><param name=\"param-name1\" value=\"param-value1\"/>"
+ "</parameters>. "
+ "Recognised rendering parameters are: author, title, keywords and dpi.",
new SequenceType[]{
new FunctionParameterSequenceType("document", Type.NODE, Cardinality.EXACTLY_ONE, "FO document"),
new FunctionParameterSequenceType("mime-type", Type.STRING, Cardinality.EXACTLY_ONE, ""),
new FunctionParameterSequenceType("parameters", Type.NODE, Cardinality.ZERO_OR_ONE, "parameters for the transform"),
new FunctionParameterSequenceType("config-file", Type.NODE, Cardinality.ZERO_OR_ONE, "FOP Processor Configuration file")
},
new FunctionParameterSequenceType("result", Type.BASE64_BINARY, Cardinality.ZERO_OR_ONE, "result")
)
};
/**
* Constructor for RenderFunction, which returns a new instance of this
* class.
*
* @param context
* @param signature
*/
public RenderFunction(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
/*
* Actual implementation of the rendering process. When a function in this
* module is called, this method is executed with the given inputs. @param
* Sequence[] args (XSL-FO, mime-type, parameters) @param Sequence
* contextSequence (default sequence)
*
* @see org.exist.xquery.BasicFunction#eval(org.exist.xquery.value.Sequence[],
* org.exist.xquery.value.Sequence)
*/
@Override
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
// gather input XSL-FO document
// if no input document (empty), return empty result as we need data to
// process
if(args[0].isEmpty()) {
return Sequence.EMPTY_SEQUENCE;
}
Item inputNode = args[0].itemAt(0);
// get mime-type
String mimeType = args[1].getStringValue();
// get parameters
Properties parameters = new Properties();
if(!args[2].isEmpty()) {
parameters = ModuleUtils.parseParameters(((NodeValue) args[2].itemAt(0)).getNode());
}
ProcessorAdapter adapter = null;
try {
adapter = ((XSLFOModule)getParentModule()).getProcessorAdapter();
NodeValue configFile = args.length == 4 ? (NodeValue)args[3].itemAt(0) : null;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ContentHandler contentHandler = adapter.getContentHandler(context.getBroker(), configFile, parameters, mimeType, baos);
// process the XSL-FO
contentHandler.startDocument();
inputNode.toSAX(context.getBroker(), contentHandler, new Properties());
contentHandler.endDocument();
// return the result
return BinaryValueFromInputStream.getInstance(context, new Base64BinaryValueType(), new ByteArrayInputStream(baos.toByteArray()));
} catch(SAXException se) {
throw new XPathException(this, se.getMessage(), se);
} finally {
if(adapter != null) {
adapter.cleanup();
}
}
}
}