/* * Copyright 2015 Anton Tananaev (anton.tananaev@gmail.com) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.traccar.web; import java.io.IOException; import java.util.Collection; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import java.util.Set; import java.util.concurrent.TimeUnit; import javax.json.Json; import javax.json.JsonObjectBuilder; import javax.servlet.AsyncContext; import javax.servlet.ServletResponse; 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.ConnectionManager; import org.traccar.helper.Log; import org.traccar.model.Device; import org.traccar.model.Position; public class AsyncServlet extends BaseServlet { private static final long ASYNC_TIMEOUT = 120000; @Override protected boolean handle(String command, HttpServletRequest req, HttpServletResponse resp) throws Exception { async(req.startAsync(), getUserId(req)); return true; } public static class AsyncSession { public static final boolean DEBUG_ASYNC = false; private static final long SESSION_TIMEOUT = 30; private static final long REQUEST_TIMEOUT = 20; private boolean destroyed; private final long userId; private final Set<Long> devices = new HashSet<>(); private Timeout sessionTimeout; private Timeout requestTimeout; private final Set<Device> deviceUpdates = new HashSet<>(); private final Set<Position> positionUpdates = new HashSet<>(); private AsyncContext activeContext; private void logEvent(String message) { if (DEBUG_ASYNC) { Log.debug("AsyncSession: " + this.hashCode() + " destroyed: " + destroyed + " " + message); } } public AsyncSession(long userId, Collection<Long> devices) { logEvent("create userId: " + userId + " devices: " + devices.size()); this.userId = userId; this.devices.addAll(devices); Collection<Position> initialPositions = Context.getConnectionManager().getInitialState(devices); for (Position position : initialPositions) { positionUpdates.add(position); } Context.getConnectionManager().addListener(devices, dataListener); } public boolean hasDevice(long deviceId) { return devices.contains(deviceId); } private final ConnectionManager.UpdateListener dataListener = new ConnectionManager.UpdateListener() { @Override public void onUpdateDevice(Device device) { synchronized (AsyncSession.this) { logEvent("onUpdateDevice deviceId: " + device.getId()); if (!destroyed) { if (requestTimeout != null) { requestTimeout.cancel(); requestTimeout = null; } deviceUpdates.add(device); if (activeContext != null) { response(); } } } } @Override public void onUpdatePosition(Position position) { synchronized (AsyncSession.this) { logEvent("onUpdatePosition deviceId: " + position.getDeviceId()); if (!destroyed) { if (requestTimeout != null) { requestTimeout.cancel(); requestTimeout = null; } positionUpdates.add(position); if (activeContext != null) { response(); } } } } }; private final TimerTask sessionTimer = new TimerTask() { @Override public void run(Timeout tmt) throws Exception { synchronized (AsyncSession.this) { logEvent("sessionTimeout"); destroyed = true; } Context.getConnectionManager().removeListener(devices, dataListener); synchronized (ASYNC_SESSIONS) { if (ASYNC_SESSIONS.get(userId) == AsyncSession.this) { ASYNC_SESSIONS.remove(userId); } } } }; private final TimerTask requestTimer = new TimerTask() { @Override public void run(Timeout tmt) throws Exception { synchronized (AsyncSession.this) { logEvent("requestTimeout"); if (!destroyed && activeContext != null) { response(); } } } }; public synchronized void request(AsyncContext context) { logEvent("request context: " + context.hashCode()); if (!destroyed) { activeContext = context; if (sessionTimeout != null) { sessionTimeout.cancel(); sessionTimeout = null; } if (!deviceUpdates.isEmpty() || !positionUpdates.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); if (Context.getConfig().getBoolean("web.oldAsyncFormat")) { result.add("data", JsonConverter.arrayToJson(positionUpdates)); } else { JsonObjectBuilder data = Json.createObjectBuilder(); data.add("devices", JsonConverter.arrayToJson(deviceUpdates)); data.add("positions", JsonConverter.arrayToJson(positionUpdates)); result.add("data", data.build()); } deviceUpdates.clear(); positionUpdates.clear(); try { response.getWriter().println(result.build().toString()); } catch (IOException error) { Log.warning(error); } activeContext.complete(); activeContext = null; sessionTimeout = GlobalTimer.getTimer().newTimeout( sessionTimer, SESSION_TIMEOUT, TimeUnit.SECONDS); } } } private static final Map<Long, AsyncSession> ASYNC_SESSIONS = new HashMap<>(); public static void sessionRefreshUser(long userId) { synchronized (ASYNC_SESSIONS) { ASYNC_SESSIONS.remove(userId); } } public static void sessionRefreshDevice(long deviceId) { synchronized (ASYNC_SESSIONS) { Iterator<Entry<Long, AsyncSession>> iterator = ASYNC_SESSIONS.entrySet().iterator(); while (iterator.hasNext()) { if (iterator.next().getValue().hasDevice(deviceId)) { iterator.remove(); } } } } private void async(final AsyncContext context, long userId) { context.setTimeout(ASYNC_TIMEOUT); HttpServletRequest req = (HttpServletRequest) context.getRequest(); synchronized (ASYNC_SESSIONS) { if (Boolean.parseBoolean(req.getParameter("first")) || !ASYNC_SESSIONS.containsKey(userId)) { Collection<Long> devices = Context.getPermissionsManager().allowedDevices(userId); ASYNC_SESSIONS.put(userId, new AsyncSession(userId, devices)); } ASYNC_SESSIONS.get(userId).request(context); } } }