/*
* JBoss, Home of Professional Open Source
* Copyright 2013, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This 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 2.1 of
* the License, or (at your option) any later version.
*
* This software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.richfaces.webapp;
import java.io.IOException;
import java.io.Serializable;
import java.text.MessageFormat;
import java.util.Collections;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.atmosphere.cpr.BroadcastFilter;
import org.atmosphere.cpr.Broadcaster.SCOPE;
import org.atmosphere.cpr.Meteor;
import org.richfaces.application.push.PushContext;
import org.richfaces.application.push.Request;
import org.richfaces.application.push.Session;
import org.richfaces.application.push.impl.RequestImpl;
import org.richfaces.log.Logger;
import org.richfaces.log.RichfacesLogger;
/**
* Serves as delegate for Atmposphere servlets - should not be used directly
*
* @author Nick Belaevski
*
*/
public class PushHandlerFilter implements Filter, Serializable {
public static final String SESSION_ATTRIBUTE_NAME = Session.class.getName();
public static final String REQUEST_ATTRIBUTE_NAME = Request.class.getName();
private static final long serialVersionUID = 5724886106704391903L;
public static final String PUSH_SESSION_ID_PARAM = "pushSessionId";
private static final Logger LOGGER = RichfacesLogger.WEBAPP.getLogger();
private int servletMajorVersion;
private transient ServletContext servletContext;
public void init(FilterConfig filterConfig) throws ServletException {
servletContext = filterConfig.getServletContext();
servletMajorVersion = servletContext.getMajorVersion();
}
/**
* Note: Filter does not delegate to chain, since it would lead into cycle by calling
* {@link PushServlet#service(ServletRequest, ServletResponse)}.
*/
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException,
ServletException {
if (request instanceof HttpServletRequest && response instanceof HttpServletResponse) {
HttpServletRequest httpReq = (HttpServletRequest) request;
HttpServletResponse httpResp = (HttpServletResponse) response;
if ("GET".equals(httpReq.getMethod())) {
String pushSessionId = httpReq.getParameter(PUSH_SESSION_ID_PARAM);
Session session = null;
if (pushSessionId != null) {
ensureServletContextAvailable(request);
PushContext pushContext = (PushContext) servletContext.getAttribute(PushContext.INSTANCE_KEY_NAME);
session = pushContext.getSessionManager().getPushSession(pushSessionId);
}
if (session == null) {
if (LOGGER.isDebugEnabled()) {
LOGGER.debug(MessageFormat.format("Session {0} was not found", pushSessionId));
}
httpResp.sendError(HttpServletResponse.SC_BAD_REQUEST);
return;
}
httpResp.setContentType("text/plain");
Meteor meteor = Meteor.build(httpReq, SCOPE.REQUEST, Collections.<BroadcastFilter>emptyList(), null);
try {
Request pushRequest = new RequestImpl(meteor, session);
httpReq.setAttribute(SESSION_ATTRIBUTE_NAME, session);
httpReq.setAttribute(REQUEST_ATTRIBUTE_NAME, pushRequest);
pushRequest.suspend();
} catch (Exception e) {
LOGGER.error(e.getMessage(), e);
}
return;
}
}
}
/**
* Ensures that servletContext instance is available, or throws exception.
*
* This method ensures compatibility with Servlet <3.0, which doesn't support obtaining {@link ServletContext} from
* {@link ServletRequest}.
*
* @param request {@link ServletRequest}
* @throws {@link IllegalStateException} when {@link ServletContext} won't be available in Servlets <3.0 environments.
* This can happen when this filter was serialized.
*/
private void ensureServletContextAvailable(ServletRequest request) {
if (servletContext == null) {
if (servletMajorVersion >= 3) {
servletContext = request.getServletContext();
} else {
throw new IllegalStateException(
"ServletContext is not available (you are using Servlets API <3.0; it might be caused by "
+ PushHandlerFilter.class.getName() + " in distributed environment)");
}
}
}
public void destroy() {
servletContext = null;
}
}