001    /*
002      GRANITE DATA SERVICES
003      Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004    
005      This file is part of Granite Data Services.
006    
007      Granite Data Services is free software; you can redistribute it and/or modify
008      it under the terms of the GNU Library General Public License as published by
009      the Free Software Foundation; either version 2 of the License, or (at your
010      option) any later version.
011    
012      Granite Data Services is distributed in the hope that it will be useful, but
013      WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014      FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015      for more details.
016    
017      You should have received a copy of the GNU Library General Public License
018      along with this library; if not, see <http://www.gnu.org/licenses/>.
019    */
020    
021    package org.granite.gravity.weblogic;
022    
023    import java.io.IOException;
024    
025    import javax.servlet.ServletConfig;
026    import javax.servlet.ServletException;
027    import javax.servlet.http.HttpServletRequest;
028    import javax.servlet.http.HttpServletResponse;
029    
030    import org.granite.gravity.AbstractGravityServlet;
031    import org.granite.gravity.AsyncHttpContext;
032    import org.granite.gravity.Gravity;
033    import org.granite.gravity.GravityManager;
034    import org.granite.gravity.GravityServletUtil;
035    import org.granite.logging.Logger;
036    import org.granite.util.ServletParams;
037    
038    import weblogic.servlet.http.AbstractAsyncServlet;
039    import weblogic.servlet.http.RequestResponseKey;
040    import flex.messaging.messages.CommandMessage;
041    import flex.messaging.messages.Message;
042    
043    /**
044     * Asynchronous servlet support for WebLogic 9.1+ servers.
045     * <br /><br />
046     * Usage:
047     * <pre>
048     * &lt;servlet&gt;
049     *     &lt;servlet-name&gt;GravityServlet&lt;/servlet-name&gt;
050     *     &lt;servlet-class&gt;org.granite.gravity.weblogic.GravityWebLogicServlet&lt;/servlet-class&gt;
051     *     
052     *     (optional parameter, default is 40,000 milliseconds)
053     *     &lt;init-param&gt;
054     *         &lt;param-name&gt;scavangeInterval&lt;/param-name&gt;
055     *         &lt;param-value&gt;40000&lt;/param-value&gt;
056     *     &lt;/init-param&gt;
057     *     
058     * &lt;/servlet&gt;
059     * </pre>
060     * 
061     * @author Franck WOLFF
062     */
063    public class GravityWebLogicServlet extends AbstractAsyncServlet {
064    
065            private static final long serialVersionUID = 1L;
066            
067            private static final Logger log = Logger.getLogger(GravityWebLogicServlet.class);
068    
069            private static final String SCAVANGE_INTERVAL = "scavangeInterval";
070    
071            @Override
072            public void init(ServletConfig config) throws ServletException {
073                    super.init(config);
074                    
075                    GravityServletUtil.init(config, new WebLogicChannelFactory());
076                    
077                    int scavangeInterval = ServletParams.get(
078                            config,
079                            SCAVANGE_INTERVAL,
080                            Integer.TYPE,
081                            AbstractAsyncServlet.DEFAULT_SCAVANGE_INTERVAL
082                    );
083                    
084                    log.info("Using scavange interval of: %s", scavangeInterval);
085                    AbstractAsyncServlet.setScavangeInterval(scavangeInterval);
086            }
087    
088            @Override
089            protected boolean doRequest(RequestResponseKey key) throws IOException, ServletException {
090                    Gravity gravity = GravityManager.getGravity(getServletContext());
091            
092                    HttpServletRequest request = key.getRequest();
093                    HttpServletResponse response = key.getResponse();
094                    
095                    try {
096                GravityServletUtil.initializeRequest(getServletConfig(), gravity, request, response);
097    
098                Message[] amf3Requests = GravityServletUtil.deserialize(gravity, request);
099    
100                log.debug(">> [AMF3 REQUESTS] %s", (Object)amf3Requests);
101    
102                Message[] amf3Responses = null;
103                
104                boolean accessed = false;
105                for (int i = 0; i < amf3Requests.length; i++) {
106                    Message amf3Request = amf3Requests[i];
107    
108                    // Ask gravity to create a specific response (will be null for connect request from tunnel).
109                    Message amf3Response = gravity.handleMessage(amf3Request);
110                    String channelId = (String)amf3Request.getClientId();
111                    
112                    // Mark current channel (if any) as accessed.
113                    if (!accessed)
114                            accessed = gravity.access(channelId);
115                    
116                    // (Re)Connect message from tunnel...
117                    if (amf3Response == null) {
118                        if (amf3Requests.length > 1)
119                            throw new IllegalArgumentException("Only one connect request is allowed on tunnel.");
120    
121                        WebLogicChannel channel = (WebLogicChannel)gravity.getChannel(channelId);
122                        if (channel == null)
123                                    throw new NullPointerException("No channel on tunnel connect");
124                        
125                        // Try to send pending messages if any (using current container thread).
126                        if (channel.runReceived(new AsyncHttpContext(request, response, amf3Request)))
127                            return false;
128    
129                        // No pending messages, wait for new ones or timeout.
130                            GravityServletUtil.setConnectMessage(request, amf3Request);
131                            key.setTimeout((int)GravityServletUtil.getLongPollingTimeout(getServletContext()));
132                            channel.setRequestResponseKey(key);
133                            return true;
134                    }
135    
136                    if (amf3Responses == null)
137                            amf3Responses = new Message[amf3Requests.length];
138                    amf3Responses[i] = amf3Response;
139                }
140    
141                log.debug("<< [AMF3 RESPONSES] %s", (Object)amf3Responses);
142    
143                GravityServletUtil.serialize(gravity, response, amf3Responses);
144            }
145            catch (IOException e) {
146                log.error(e, "Gravity message error");
147                throw e;
148            }
149            catch (Exception e) {
150                log.error(e, "Gravity message error");
151                throw new ServletException(e);
152            }
153            finally {
154                    GravityServletUtil.cleanupRequest(request);
155            }
156                    return false;
157            }
158    
159            @Override
160            protected void doResponse(RequestResponseKey key, Object context) throws IOException, ServletException {
161                    WebLogicChannel channel = (WebLogicChannel)context;
162            HttpServletRequest request = key.getRequest();
163            HttpServletResponse response = key.getResponse();
164            Message requestMessage = AbstractGravityServlet.getConnectMessage(request);
165                    
166                    channel.runReceived(new AsyncHttpContext(request, response, requestMessage));
167            }
168    
169            @Override
170            protected void doTimeout(RequestResponseKey key) throws IOException, ServletException {
171                    Gravity gravity = GravityManager.getGravity(getServletContext());
172                    CommandMessage amf3Request = GravityServletUtil.getConnectMessage(key.getRequest());
173                    String channelId = (String)amf3Request.getClientId();
174                    WebLogicChannel channel = (WebLogicChannel)gravity.getChannel(channelId);
175                    channel.setRequestResponseKey(null);
176            }
177    }