/*
* Copyright 2005-2014 the original author or authors.
*
* Licensed 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.springframework.ws.server.endpoint.interceptor;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import javax.xml.transform.Source;
import javax.xml.transform.Templates;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.XMLReaderFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.io.Resource;
import org.springframework.util.Assert;
import org.springframework.ws.WebServiceMessage;
import org.springframework.ws.context.MessageContext;
import org.springframework.ws.server.EndpointInterceptor;
import org.springframework.xml.transform.ResourceSource;
import org.springframework.xml.transform.TransformerObjectSupport;
/**
* Interceptor that transforms the payload of {@code WebServiceMessage}s using XSLT stylesheet. Allows for seperate
* stylesheets for request and response. This interceptor is especially useful when supporting with multiple version of
* a Web service: you can transform the older message format to the new format.
*
* <p>The stylesheets to use can be set using the {@code requestXslt} and {@code responseXslt} properties. Both
* of these are optional: if not set, the message is simply not transformed. Setting one of the two is required,
* though.
*
* @author Arjen Poutsma
* @see #setRequestXslt(org.springframework.core.io.Resource)
* @see #setResponseXslt(org.springframework.core.io.Resource)
* @since 1.0.0
*/
public class PayloadTransformingInterceptor extends TransformerObjectSupport
implements EndpointInterceptor, InitializingBean {
private static final Log logger = LogFactory.getLog(PayloadTransformingInterceptor.class);
private Resource requestXslt;
private Resource responseXslt;
private Templates requestTemplates;
private Templates responseTemplates;
/** Sets the XSLT stylesheet to use for transforming incoming request. */
public void setRequestXslt(Resource requestXslt) {
this.requestXslt = requestXslt;
}
/** Sets the XSLT stylesheet to use for transforming outgoing responses. */
public void setResponseXslt(Resource responseXslt) {
this.responseXslt = responseXslt;
}
/**
* Transforms the request message in the given message context using a provided stylesheet. Transformation only
* occurs if the {@code requestXslt} has been set.
*
* @param messageContext the message context
* @return always returns {@code true}
* @see #setRequestXslt(org.springframework.core.io.Resource)
*/
@Override
public boolean handleRequest(MessageContext messageContext, Object endpoint) throws Exception {
if (requestTemplates != null) {
WebServiceMessage request = messageContext.getRequest();
Transformer transformer = requestTemplates.newTransformer();
transformMessage(request, transformer);
logger.debug("Request message transformed");
}
return true;
}
/**
* Transforms the response message in the given message context using a stylesheet. Transformation only occurs if
* the {@code responseXslt} has been set.
*
* @param messageContext the message context
* @return always returns {@code true}
* @see #setResponseXslt(org.springframework.core.io.Resource)
*/
@Override
public boolean handleResponse(MessageContext messageContext, Object endpoint) throws Exception {
if (responseTemplates != null) {
WebServiceMessage response = messageContext.getResponse();
Transformer transformer = responseTemplates.newTransformer();
transformMessage(response, transformer);
logger.debug("Response message transformed");
}
return true;
}
private void transformMessage(WebServiceMessage message, Transformer transformer) throws TransformerException {
ByteArrayOutputStream os = new ByteArrayOutputStream();
transformer.transform(message.getPayloadSource(), new StreamResult(os));
ByteArrayInputStream is = new ByteArrayInputStream(os.toByteArray());
transform(new StreamSource(is), message.getPayloadResult());
}
/** Does nothing by default. Faults are not transformed. */
@Override
public boolean handleFault(MessageContext messageContext, Object endpoint) throws Exception {
return true;
}
/** Does nothing by default.*/
@Override
public void afterCompletion(MessageContext messageContext, Object endpoint, Exception ex) {
}
@Override
public void afterPropertiesSet() throws Exception {
if (requestXslt == null && responseXslt == null) {
throw new IllegalArgumentException("Setting either 'requestXslt' or 'responseXslt' is required");
}
TransformerFactory transformerFactory = getTransformerFactory();
XMLReader xmlReader = XMLReaderFactory.createXMLReader();
xmlReader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
if (requestXslt != null) {
Assert.isTrue(requestXslt.exists(), "requestXslt \"" + requestXslt + "\" does not exit");
if (logger.isInfoEnabled()) {
logger.info("Transforming request using " + requestXslt);
}
Source requestSource = new ResourceSource(xmlReader, requestXslt);
requestTemplates = transformerFactory.newTemplates(requestSource);
}
if (responseXslt != null) {
Assert.isTrue(responseXslt.exists(), "responseXslt \"" + responseXslt + "\" does not exit");
if (logger.isInfoEnabled()) {
logger.info("Transforming response using " + responseXslt);
}
Source responseSource = new ResourceSource(xmlReader, responseXslt);
responseTemplates = transformerFactory.newTemplates(responseSource);
}
}
}