/*
============================================================================
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.generation;
import java.io.IOException;
import java.io.InputStream;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.environment.http.HttpEnvironment;
import org.apache.cocoon.util.RequestForwardingHttpMethod;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HttpConnection;
import org.apache.commons.httpclient.HttpState;
import org.apache.commons.httpclient.HttpURL;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.excalibur.xml.sax.SAXParser;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
/**
* This is a generic HTTP proxy, designed to handle any possible HTTP method,
* but with a particular bias towards WebDAV. As of now it's pretty unstable, but
* still it might be a good proof of concept towards a pure HTTP(++) proxy.
*
* TODO: doesn't handle authentication properly
* TODO: doesn't handle (and doubt it'll ever will) HTTP/1.1 keep-alive
*
* @author <a href="mailto:gianugo@apache.org">Gianugo Rabellino</a>
* @version $Id: GenericProxyGenerator.java,v 1.2 2003/09/04 09:38:37 cziegeler Exp $
*/
public class GenericProxyGenerator extends ServiceableGenerator {
/** The real URL to forward requests to */
HttpURL destination;
/** The current request */
HttpServletRequest request;
/** The current response */
HttpServletResponse response;
/** The current request */
String path;
SAXParser parser;
/**
* Compose and get a SAX parser for further use.
*
* @see org.apache.avalon.framework.component.Composable#compose(org.apache.avalon.framework.component.ComponentManager)
*/
public void service(ServiceManager manager) throws ServiceException {
super.service(manager);
this.parser = (SAXParser)manager.lookup(SAXParser.ROLE);
}
/**
* Dispose
*/
public void dispose() {
if ( this.manager != null ) {
this.manager.release( this.parser );
this.parser = null;
}
super.dispose();
}
/**
* Setup this component by getting the (required) "url" parameter and the
* (optional) "path" parameter. If path is not specified, the request URI will
* be used and forwarded.
*
* TODO: handle query string
*
* @see org.apache.cocoon.sitemap.SitemapModelComponent#setup(org.apache.cocoon.environment.SourceResolver, java.util.Map, java.lang.String, org.apache.avalon.framework.parameters.Parameters)
*/
public void setup(
SourceResolver resolver,
Map objectModel,
String src,
Parameters par)
throws ProcessingException, SAXException, IOException {
String url = par.getParameter("url", null);
request = (HttpServletRequest)objectModel.get(HttpEnvironment.HTTP_REQUEST_OBJECT);
response = (HttpServletResponse)objectModel.get(HttpEnvironment.HTTP_RESPONSE_OBJECT);
if (url == null) {
throw new ProcessingException("Missing the \"url\" parameter");
}
path = par.getParameter("path", null);
if (path == null)
path = request.getRequestURI();
destination = new HttpURL(url);
}
/**
* Get the request data, pass them on to the forwarder and return the result.
*
* TODO: much better header handling
* TODO: handle non XML and bodyless responses (probably needs a smarter Serializer,
* since some XML has to go through the pipeline anyway.
*
* @see org.apache.cocoon.generation.Generator#generate()
*/
public void generate()
throws IOException, SAXException, ProcessingException {
RequestForwardingHttpMethod method =
new RequestForwardingHttpMethod(request, destination);
// Build the forwarded connection
HttpConnection conn = new HttpConnection(destination.getHost(), destination.getPort());
HttpState state = new HttpState();
state.setCredentials(null, destination.getHost(),
new UsernamePasswordCredentials(destination.getUser(), destination.getPassword()));
method.setPath(path);
// Execute the method
method.execute(state, conn);
// Send the output to the client: set the status code...
response.setStatus(method.getStatusCode());
// ... retrieve the headers from the origin server and pass them on
Header[] methodHeaders = method.getResponseHeaders();
for (int i = 0; i < methodHeaders.length; i++) {
// there is more than one DAV header
if (methodHeaders[i].getName().equals("DAV")) {
response.addHeader(methodHeaders[i].getName(), methodHeaders[i].getValue());
} else if (methodHeaders[i].getName().equals("Content-Length")) {
// drop the original Content-Length header. Don't ask me why but there
// it's always one byte off
} else {
response.setHeader(methodHeaders[i].getName(), methodHeaders[i].getValue());
}
}
// no HTTP keepalives here...
response.setHeader("Connection", "close");
// Parse the XML, if any
if (method.getResponseHeader("Content-Type").getValue().startsWith("text/xml")) {
InputStream stream = method.getResponseBodyAsStream();
parser.parse(new InputSource(stream), this.contentHandler, this.lexicalHandler);
} else {
// Just send a dummy XML
this.contentHandler.startDocument();
this.contentHandler.startElement(null, "no-xml-content", "no-xml-content", new AttributesImpl());
this.contentHandler.endElement(null, "no-xml-content", "no-xml-content");
this.contentHandler.endDocument();
}
// again, no keepalive here.
conn.close();
}
}