/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
*
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.rewrite;
import java.io.IOException;
import javax.annotation.PostConstruct;
import javax.servlet.DispatcherType;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import com.caucho.config.ConfigException;
import com.caucho.config.Configurable;
import com.caucho.config.types.Period;
import com.caucho.server.dispatch.ServletConfigImpl;
import com.caucho.server.webapp.WebApp;
import com.caucho.servlets.HttpProxyServlet;
/**
* Dispatches a request to a backend server using HTTP as the proxy
* protocol.
*
* <pre>
* <web-app xmlns:resin="urn:java:com.caucho.resin">
*
* <resin:HttpProxy regexp="^/remote">
* <address>127.0.0.1:8080</address>
* </resin:HttpProxy>
*
* </web-app>
* </pre>
*/
@Configurable
public class HttpProxy extends AbstractTargetDispatchRule
{
private HttpProxyServlet _proxyServlet;
private ServletConfigImpl _servlet;
public HttpProxy()
{
_proxyServlet = new HttpProxyServlet();
_servlet = new ServletConfigImpl();
_servlet.setServletName("resin-dispatch-lb");
_servlet.setServlet(_proxyServlet);
}
/**
* Adds a backend HTTP server address like "127.0.0.1:8081"
*
* @param address the backend address likst "127.0.0.1:8081"
*/
@Configurable
public void addAddress(String address)
{
_proxyServlet.addAddress(address);
}
/**
* Sets the timeout to recover from a failed connection to the backend.
*
* @param period the recover timeout
*/
@Configurable
public void setFailRecoverTime(Period period)
{
_proxyServlet.setFailRecoverTime(period);
}
@PostConstruct
public void init()
throws ConfigException
{
try {
_proxyServlet.init();
WebApp webApp = WebApp.getCurrent();
if (webApp != null)
webApp.addServlet(_servlet);
}
catch (ServletException ex) {
throw ConfigException.create(ex);
}
}
@Override
public FilterChain createDispatch(DispatcherType type,
String uri,
String queryString,
String target,
FilterChain next)
{
try {
return new ProxyFilterChain(_servlet.createServletChain(),
uri, queryString);
} catch (ServletException e) {
throw ConfigException.create(e);
}
}
public static class ProxyFilterChain implements FilterChain {
private final FilterChain _next;
private final String _uri;
private final String _queryString;
ProxyFilterChain(FilterChain next, String uri, String queryString)
{
_next = next;
_uri = uri;
_queryString = queryString;
}
public void doFilter(ServletRequest req,
ServletResponse res)
throws IOException, ServletException
{
_next.doFilter(new ProxyRequest(req, _uri, _queryString), res);
}
}
public static class ProxyRequest extends HttpServletRequestWrapper {
private String _uri;
private String _queryString;
ProxyRequest(ServletRequest req,
String uri,
String queryString)
{
super((HttpServletRequest) req);
_uri = uri;
_queryString = queryString;
}
/**
* Returns the proxy uri
*/
public String getRequestURI()
{
return _uri;
}
/**
* Returns the proxy query string
*/
public String getQueryString()
{
return _queryString;
}
}
}