Implement async position update

1 files changed, 163 insertions, 14 deletions

diff --git a/src/org/traccar/http/MainServlet.java b/src/org/traccar/http/MainServlet.java
index 7483b22b4..655b47312 100644
--- a/src/org/traccar/http/MainServlet.java
+++ b/src/org/traccar/http/MainServlet.java
@@ -17,6 +17,11 @@ package org.traccar.http;
 
 import java.io.IOException;
 import java.sql.SQLException;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
 import javax.json.Json;
 import javax.json.JsonObjectBuilder;
 import javax.servlet.AsyncContext;
@@ -25,13 +30,21 @@ import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+import org.jboss.netty.util.Timeout;
+import org.jboss.netty.util.TimerTask;
 import org.traccar.Context;
+import org.traccar.GlobalTimer;
+import org.traccar.database.DataCache;
+import org.traccar.database.ObjectConverter;
 import org.traccar.helper.Log;
+import org.traccar.model.Position;
 
 public class MainServlet extends HttpServlet {
 
-    private static final String USER_ID = "userId";
+    private static final long ASYNC_TIMEOUT = 120000;
 
+    private static final String USER_ID = "userId";
+    
     @Override
     protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
 
@@ -50,25 +63,161 @@ public class MainServlet extends HttpServlet {
         }
     }
     
-    private void async(final AsyncContext context) {
-        context.start(new Runnable() {
+    public class AsyncSession {
+        
+        private static final boolean DEBUG_ASYNC = true;
+        
+        private static final long SESSION_TIMEOUT = 30;
+        private static final long REQUEST_TIMEOUT = 30;
+        
+        private boolean destroyed;
+        private final long userId;
+        private final List<Long> devices;
+        private Timeout sessionTimeout;
+        private Timeout requestTimeout;
+        private final Map<Long, Position> positions = new HashMap<Long, Position>();
+        private AsyncContext activeContext;
+        
+        private void logEvent(String message) {
+            if (DEBUG_ASYNC) {
+                Log.debug("AsyncSession: " + this.hashCode() + " destroyed: " + destroyed + " " + message);
+            }
+        }
+        
+        public AsyncSession(long userId, List<Long> devices) {
+            logEvent("create userId: " + userId + " devices: " + devices.size());
+            this.userId = userId;
+            this.devices = devices;
+        }
+
+        @Override
+        protected void finalize() throws Throwable {
+            logEvent("finalize");
+        }
+        
+        private final DataCache.DataCacheListener dataListener = new DataCache.DataCacheListener() {
+            @Override
+            public void onUpdate(Position position) {
+                synchronized (AsyncSession.this) {
+                    logEvent("onUpdate deviceId: " + position.getDeviceId());
+                    if (!destroyed) {
+                        if (requestTimeout != null) {
+                            requestTimeout.cancel();
+                            requestTimeout = null;
+                        }
+                        positions.put(position.getDeviceId(), position);
+                        if (activeContext != null) {
+                            response();
+                        }
+                    }
+                }
+            }
+        };
+        
+        private final TimerTask sessionTimer = new TimerTask() {
+            @Override
+            public void run(Timeout tmt) throws Exception {
+                synchronized (AsyncSession.this) {
+                    logEvent("sessionTimeout");
+                    Context.getDataCache().removeListener(devices, dataListener);
+                    synchronized (asyncSessions) {
+                        asyncSessions.remove(userId);
+                    }
+                    destroyed = true;
+                }
+            }
+        };
+                
+        private final TimerTask requestTimer = new TimerTask() {
             @Override
-            public void run() {
+            public void run(Timeout tmt) throws Exception {
+                synchronized (AsyncSession.this) {
+                    logEvent("requestTimeout");
+                    if (!destroyed) {
+                        if (activeContext != null) {
+                            response();
+                        }
+                    }
+                }
+            }
+        };
+                
+        public synchronized void init() {
+            logEvent("init");
+            Collection<Position> initialPositions = Context.getDataCache().getInitialState(devices);
+            for (Position position : initialPositions) {
+                positions.put(position.getDeviceId(), position);
+            }
+            
+            Context.getDataCache().addListener(devices, dataListener);
+        }
+        
+        public synchronized void request(AsyncContext context) {
+            logEvent("request context: " + context.hashCode());
+            if (!destroyed) {
+                activeContext = context;
+                if (sessionTimeout != null) {
+                    sessionTimeout.cancel();
+                    sessionTimeout = null;
+                }
+
+                if (!positions.isEmpty()) {
+                    response();
+                } else {
+                    requestTimeout = GlobalTimer.getTimer().newTimeout(
+                            requestTimer, REQUEST_TIMEOUT, TimeUnit.SECONDS);
+                }
+            }
+        }
+        
+        private synchronized void response() {
+            logEvent("response context: " + activeContext.hashCode());
+            if (!destroyed) {
+                ServletResponse response = activeContext.getResponse();
+
+                JsonObjectBuilder result = Json.createObjectBuilder();
+                result.add("success", true);
+                result.add("data", ObjectConverter.convert(positions.values()));
+                positions.clear();
+
                 try {
-                    Thread.sleep(5000); // DELME
+                    response.getWriter().println(result.build().toString());
+                } catch (IOException error) {
+                    Log.warning(error);
+                }
 
-                    ServletResponse response = context.getResponse();
-                    response.getWriter().println("{ success: true, data: ["+
-                            "{ id: 1, device_id: 1, time: \"2012-04-23T18:25:43.511Z\", latitude: 60, longitude: 30, speed: 0, course: 0 }," +
-                            "{ id: 2, device_id: 2, time: \"2012-04-23T19:25:43.511Z\", latitude: 61, longitude: 31, speed: 0, course: 0 }" +
-                            "] }");
-                    context.complete();
+                activeContext.complete();
+                activeContext = null;
 
-                } catch (Exception ex) {
-                    Log.warning(ex);
+                sessionTimeout = GlobalTimer.getTimer().newTimeout(
+                        sessionTimer, SESSION_TIMEOUT, TimeUnit.SECONDS);
+            }
+        }
+        
+    }
+    
+    private final Map<Long, AsyncSession> asyncSessions = new HashMap<Long, AsyncSession>();
+    
+    private void async(final AsyncContext context) {
+        
+        context.setTimeout(60000);
+        HttpServletRequest req = (HttpServletRequest) context.getRequest();
+        long userId = (Long) req.getSession().getAttribute(USER_ID);
+        
+        synchronized (asyncSessions) {
+            
+            if (!asyncSessions.containsKey(userId)) {
+                try {
+                    List<Long> devices = Context.getDataManager().getDeviceList(userId);
+                    asyncSessions.put(userId, new AsyncSession(userId, devices));
+                } catch (SQLException error) {
+                    Log.warning(error);
                 }
+                asyncSessions.get(userId).init();
             }
-        });
+            
+            asyncSessions.get(userId).request(context);
+        }
     }
     
     private void device(HttpServletRequest req, HttpServletResponse resp) throws IOException {