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);
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                    WebLogicChannelFactory channelFactory = new WebLogicChannelFactory(gravity);
092            
093                    HttpServletRequest request = key.getRequest();
094                    HttpServletResponse response = key.getResponse();
095                    
096                    try {
097                GravityServletUtil.initializeRequest(getServletConfig(), gravity, request, response);
098    
099                Message[] amf3Requests = GravityServletUtil.deserialize(gravity, request);
100    
101                log.debug(">> [AMF3 REQUESTS] %s", (Object)amf3Requests);
102    
103                Message[] amf3Responses = null;
104                
105                boolean accessed = false;
106                for (int i = 0; i < amf3Requests.length; i++) {
107                    Message amf3Request = amf3Requests[i];
108    
109                    // Ask gravity to create a specific response (will be null for connect request from tunnel).
110                    Message amf3Response = gravity.handleMessage(channelFactory, amf3Request);
111                    String channelId = (String)amf3Request.getClientId();
112                    
113                    // Mark current channel (if any) as accessed.
114                    if (!accessed)
115                            accessed = gravity.access(channelId);
116                    
117                    // (Re)Connect message from tunnel...
118                    if (amf3Response == null) {
119                        if (amf3Requests.length > 1)
120                            throw new IllegalArgumentException("Only one connect request is allowed on tunnel.");
121    
122                        WebLogicChannel channel = gravity.getChannel(channelFactory, channelId);
123                        if (channel == null)
124                                    throw new NullPointerException("No channel on tunnel connect");
125                        
126                        // Try to send pending messages if any (using current container thread).
127                        if (channel.runReceived(new AsyncHttpContext(request, response, amf3Request)))
128                            return false;
129    
130                        // No pending messages, wait for new ones or timeout.
131                            GravityServletUtil.setConnectMessage(request, amf3Request);
132                            key.setTimeout((int)GravityServletUtil.getLongPollingTimeout(getServletContext()));
133                            channel.setRequestResponseKey(key);
134                            return true;
135                    }
136    
137                    if (amf3Responses == null)
138                            amf3Responses = new Message[amf3Requests.length];
139                    amf3Responses[i] = amf3Response;
140                }
141    
142                log.debug("<< [AMF3 RESPONSES] %s", (Object)amf3Responses);
143    
144                GravityServletUtil.serialize(gravity, response, amf3Responses);
145            }
146            catch (IOException e) {
147                log.error(e, "Gravity message error");
148                throw e;
149            }
150            catch (Exception e) {
151                log.error(e, "Gravity message error");
152                throw new ServletException(e);
153            }
154            finally {
155                    GravityServletUtil.cleanupRequest(request);
156            }
157                    return false;
158            }
159    
160            @Override
161            protected void doResponse(RequestResponseKey key, Object context) throws IOException, ServletException {
162                    WebLogicChannel channel = (WebLogicChannel)context;
163            HttpServletRequest request = key.getRequest();
164            HttpServletResponse response = key.getResponse();
165            Message requestMessage = AbstractGravityServlet.getConnectMessage(request);
166                    
167                    channel.runReceived(new AsyncHttpContext(request, response, requestMessage));
168            }
169    
170            @Override
171            protected void doTimeout(RequestResponseKey key) throws IOException, ServletException {
172                    Gravity gravity = GravityManager.getGravity(getServletContext());
173                    WebLogicChannelFactory channelFactory = new WebLogicChannelFactory(gravity);
174                    
175                    CommandMessage amf3Request = GravityServletUtil.getConnectMessage(key.getRequest());
176                    String channelId = (String)amf3Request.getClientId();
177                    WebLogicChannel channel = gravity.getChannel(channelFactory, channelId);
178                    channel.setRequestResponseKey(null);
179            }
180    }