001/**
002 *   GRANITE DATA SERVICES
003 *   Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004 *
005 *   This file is part of the Granite Data Services Platform.
006 *
007 *   Granite Data Services is free software; you can redistribute it and/or
008 *   modify it under the terms of the GNU Lesser General Public
009 *   License as published by the Free Software Foundation; either
010 *   version 2.1 of the License, or (at your option) any later version.
011 *
012 *   Granite Data Services is distributed in the hope that it will be useful,
013 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
014 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015 *   General Public License for more details.
016 *
017 *   You should have received a copy of the GNU Lesser General Public
018 *   License along with this library; if not, write to the Free Software
019 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020 *   USA, or see <http://www.gnu.org/licenses/>.
021 */
022package org.granite.gravity.gae;
023
024import java.io.IOException;
025import java.util.List;
026
027import javax.servlet.ServletException;
028import javax.servlet.http.HttpServletRequest;
029import javax.servlet.http.HttpServletResponse;
030
031import org.granite.gravity.AbstractGravityServlet;
032import org.granite.gravity.Gravity;
033import org.granite.gravity.GravityManager;
034import org.granite.logging.Logger;
035
036import com.google.apphosting.api.DeadlineExceededException;
037
038import flex.messaging.messages.AsyncMessage;
039import flex.messaging.messages.Message;
040
041
042/**
043 * @author William DRAI
044 */
045public class GravityGAEServlet extends AbstractGravityServlet {
046
047    private static final long serialVersionUID = 1L;
048
049    private static final Logger log = Logger.getLogger(GravityGAEServlet.class);
050
051
052    private static long GAE_TIMEOUT = 20000L;
053    private static long GAE_POLLING_INTERVAL = 500L;
054
055
056    @Override
057    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
058        doPost(req,resp);
059    }
060
061    @Override
062    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
063
064                Gravity gravity = GravityManager.getGravity(getServletContext());
065                GAEChannelFactory channelFactory = new GAEChannelFactory((GAEGravity)gravity);
066                
067                try {
068                        // Setup context (thread local GraniteContext, etc.)
069                        initializeRequest(gravity, request, response);
070                        
071                        // New Request.
072                        Message[] amf3Requests = deserialize(gravity, request);
073
074            log.debug(">> [AMF3 REQUESTS] %s", (Object)amf3Requests);
075
076            Message[] amf3Responses = null;
077            
078            boolean accessed = false;
079            for (int i = 0; i < amf3Requests.length; i++) {
080                Message amf3Request = amf3Requests[i];
081                
082                // Ask gravity to create a specific response (will be null for connect request from tunnel).
083                Message amf3Response = gravity.handleMessage(channelFactory, amf3Request);
084                String channelId = (String)amf3Request.getClientId();
085                
086                // Mark current channel (if any) as accessed.
087                if (!accessed)
088                        accessed = gravity.access(channelId);
089                
090                // (Re)Connect message from tunnel.
091                if (amf3Response == null) {
092                    if (amf3Requests.length > 1)
093                        throw new IllegalArgumentException("Only one request is allowed on tunnel.");
094
095                        GAEChannel channel = gravity.getChannel(channelFactory, channelId);
096                        if (channel == null)
097                                throw new NullPointerException("No channel on connect");
098                        
099                        long pollingInterval = gravity.getGravityConfig().getExtra().get("gae/@polling-interval", Long.TYPE, GAE_POLLING_INTERVAL);
100
101                    long initialTime = System.currentTimeMillis();
102                    do {
103                        // Get messages or wait
104                        List<Message> messages = null;
105                        synchronized (channel) {
106                            // Get pending messages from client queue
107                            messages = channel.takeMessages();
108                        }
109        
110                        // Send the messages
111                        if (messages != null) {
112                                amf3Responses = messages.toArray(new Message[0]);
113                                ((AsyncMessage)amf3Responses[i]).setCorrelationId(amf3Requests[i].getMessageId());
114                                break;
115                        }
116                        
117                        try {
118                                Thread.sleep(pollingInterval);
119                        }
120                        catch (InterruptedException e) {
121                                break;
122                        }
123                        catch (DeadlineExceededException e) {
124                                break;
125                        }
126                    }
127                    while (System.currentTimeMillis()-initialTime < GAE_TIMEOUT);
128                    
129                    if (amf3Responses == null)
130                        amf3Responses = new Message[0];
131                }
132                else {
133                        if (amf3Responses == null)
134                                amf3Responses = new Message[amf3Requests.length];
135                        amf3Responses[i] = amf3Response;
136                }
137            }
138
139            log.debug("<< [AMF3 RESPONSES] %s", (Object)amf3Responses);
140
141            serialize(gravity, response, amf3Responses);
142                }
143        catch (IOException e) {
144            log.error(e, "Gravity message error");
145            throw e;
146        }
147        catch (Exception e) {
148            log.error(e, "Gravity message error");
149            throw new ServletException(e);
150        }
151                finally {
152                        // Cleanup context (thread local GraniteContext, etc.)
153                        cleanupRequest(request);
154                }
155    }
156}