/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-09 The eXist Project
* http://exist-db.org
*
* 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.functions.util;
import org.apache.log4j.Logger;
import org.exist.external.org.apache.commons.io.output.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.util.Properties;
import javax.xml.transform.OutputKeys;
import org.exist.dom.QName;
import org.exist.storage.serializers.Serializer;
import org.exist.util.serializer.SAXSerializer;
import org.exist.util.serializer.SerializerPool;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Option;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.BooleanValue;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceIterator;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
import org.xml.sax.SAXException;
public class Serialize extends BasicFunction {
protected static final Logger logger = Logger.getLogger(Serialize.class);
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("serialize", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Writes the node set passed in parameter $a into a file on the file system. The " +
"full path to the file is specified in parameter $b. $c contains a " +
"sequence of zero or more serialization parameters specified as key=value pairs. The " +
"serialization options are the same as those recognized by \"declare option exist:serialize\". " +
"The function does NOT automatically inherit the serialization options of the XQuery it is " +
"called from. False is returned if the " +
"specified file can not be created or is not writable, true on success. The empty " +
"sequence is returned if the argument sequence is empty.",
new SequenceType[] {
new SequenceType(Type.NODE, Cardinality.ZERO_OR_MORE),
new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE),
new SequenceType(Type.STRING, Cardinality.ZERO_OR_MORE)
},
new SequenceType(Type.BOOLEAN, Cardinality.ZERO_OR_ONE),
"Use the file:serialize() function in the file extension module instead!"
),
new FunctionSignature(
new QName("serialize", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Returns the Serialized node set passed in parameter $node-set. $parameters contains a " +
"sequence of zero or more serialization parameters specified as key=value pairs. The " +
"serialization options are the same as those recognized by \"declare option exist:serialize\". " +
"The function does NOT automatically inherit the serialization options of the XQuery it is " +
"called from.",
new SequenceType[] {
new FunctionParameterSequenceType("node-set", Type.NODE, Cardinality.ZERO_OR_MORE, "The node set to serialize"),
new FunctionParameterSequenceType("parameters", Type.STRING, Cardinality.ZERO_OR_MORE, "The serialization parameters")
},
new FunctionParameterSequenceType("result", Type.STRING, Cardinality.ZERO_OR_ONE, "the string containing the serialized node set.")
)
};
public Serialize(XQueryContext context, FunctionSignature signature)
{
super(context, signature);
}
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException
{
if(args[0].isEmpty()) {
return Sequence.EMPTY_SEQUENCE;
}
Properties outputProperties = null;
OutputStream os = null;
if(args.length == 3)
{
// TODO: Remove this conditional in eXist 2.0 since the function has been deprecated.
/** serialize to disk **/
// check the file output path
String path = args[1].itemAt(0).getStringValue();
File file = new File(path);
if (file.isDirectory()) {
logger.debug("Output file is a directory: " + file.getAbsolutePath());
return BooleanValue.FALSE;
}
if (file.exists() && !file.canWrite()) {
logger.debug("Cannot write to file " + file.getAbsolutePath());
return BooleanValue.FALSE;
}
//parse serialization options from third argument to function
outputProperties = parseSerializationOptions(args[2].iterate());
//setup output stream for file
try
{
os = new FileOutputStream(file);
}
catch(IOException e)
{
throw new XPathException(this, "A problem ocurred while serializing the node set: " + e.getMessage(), e);
}
//do the serialization
serialize(args[0].iterate(), outputProperties, os);
return BooleanValue.TRUE;
}
else
{
/** serialize to string **/
//parse serialization options from second argument to function
outputProperties = parseSerializationOptions(args[1].iterate());
//setup output stream for byte array
os = new ByteArrayOutputStream();
//do the serialization
serialize(args[0].iterate(), outputProperties, os);
try
{
String encoding = outputProperties.getProperty(OutputKeys.ENCODING, "UTF-8");
return new StringValue(new String(((ByteArrayOutputStream)os).toByteArray(), encoding));
}
catch(UnsupportedEncodingException e)
{
throw new XPathException(this, "A problem ocurred while serializing the node set: " + e.getMessage(), e);
}
}
}
private Properties parseSerializationOptions(SequenceIterator siSerializeParams) throws XPathException
{
//parse serialization options
Properties outputProperties = new Properties();
outputProperties.setProperty(OutputKeys.INDENT, "yes");
outputProperties.setProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
while(siSerializeParams.hasNext())
{
String serializeParams = siSerializeParams.nextItem().getStringValue();
String params[] = serializeParams.split(" ");
for(String param : params)
{
String opt[] = Option.parseKeyValuePair(param);
outputProperties.setProperty(opt[0], opt[1]);
}
}
return outputProperties;
}
private void serialize(SequenceIterator siNode, Properties outputProperties, OutputStream os) throws XPathException
{
// serialize the node set
SAXSerializer sax = (SAXSerializer) SerializerPool.getInstance().borrowObject(SAXSerializer.class);
try
{
String encoding = outputProperties.getProperty(OutputKeys.ENCODING, "UTF-8");
Writer writer = new OutputStreamWriter(os, encoding);
sax.setOutput(writer, outputProperties);
Serializer serializer = context.getBroker().getSerializer();
serializer.reset();
serializer.setProperties(outputProperties);
serializer.setSAXHandlers(sax, sax);
sax.startDocument();
while(siNode.hasNext())
{
NodeValue next = (NodeValue)siNode.nextItem();
serializer.toSAX(next);
}
sax.endDocument();
writer.close();
}
catch(SAXException e)
{
throw new XPathException(this, "A problem ocurred while serializing the node set: " + e.getMessage(), e);
}
catch (IOException e)
{
throw new XPathException(this, "A problem ocurred while serializing the node set: " + e.getMessage(), e);
}
finally
{
SerializerPool.getInstance().returnObject(sax);
}
}
}