From fceecda9e32313916ab8695192c6e12bb59bd717 Mon Sep 17 00:00:00 2001 From: Anton Tananaev Date: Thu, 30 Apr 2015 16:48:17 +1200 Subject: Separate async API servlet --- src/org/traccar/http/AsyncServlet.java | 201 +++++++++++++++++++++++++++++++++ 1 file changed, 201 insertions(+) create mode 100644 src/org/traccar/http/AsyncServlet.java (limited to 'src/org/traccar/http/AsyncServlet.java') diff --git a/src/org/traccar/http/AsyncServlet.java b/src/org/traccar/http/AsyncServlet.java new file mode 100644 index 000000000..c66126667 --- /dev/null +++ b/src/org/traccar/http/AsyncServlet.java @@ -0,0 +1,201 @@ +/* + * 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.http; + +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; + +import javax.json.Json; +import javax.json.JsonObjectBuilder; +import javax.servlet.AsyncContext; +import javax.servlet.ServletException; +import javax.servlet.ServletResponse; +import javax.servlet.http.HttpServlet; +import javax.servlet.http.HttpServletRequest; +import javax.servlet.http.HttpServletResponse; +import java.io.IOException; +import java.sql.SQLException; +import java.util.Collection; +import java.util.HashMap; +import java.util.Map; +import java.util.concurrent.TimeUnit; + +public class AsyncServlet extends HttpServlet { + + private static final long ASYNC_TIMEOUT = 120000; + + @Override + protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { + async(req.startAsync()); + } + + 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 Collection devices; + private Timeout sessionTimeout; + private Timeout requestTimeout; + private final Map positions = new HashMap(); + private AsyncContext activeContext; + + private void logEvent(String message) { + if (DEBUG_ASYNC) { + Log.debug("AsyncSession: " + this.hashCode() + " destroyed: " + destroyed + " " + message); + } + } + + public AsyncSession(long userId, Collection devices) { + logEvent("create userId: " + userId + " devices: " + devices.size()); + this.userId = userId; + this.devices = devices; + + Collection initialPositions = Context.getDataCache().getInitialState(devices); + for (Position position : initialPositions) { + positions.put(position.getDeviceId(), position); + } + + Context.getDataCache().addListener(devices, dataListener); + } + + @Override + protected void finalize() throws Throwable { + super.finalize(); + 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(Timeout tmt) throws Exception { + synchronized (AsyncSession.this) { + logEvent("requestTimeout"); + if (!destroyed) { + if (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 (!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.arrayToJson(positions.values())); + positions.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 final Map asyncSessions = new HashMap(); + + private void async(final AsyncContext context) { + + context.setTimeout(ASYNC_TIMEOUT); + HttpServletRequest req = (HttpServletRequest) context.getRequest(); + long userId = (Long) req.getSession().getAttribute(MainServlet.USER_ID); + + synchronized (asyncSessions) { + + if (!asyncSessions.containsKey(userId)) { + Collection devices = Context.getPermissionsManager().allowedDevices(userId); + asyncSessions.put(userId, new AsyncSession(userId, devices)); + } + + asyncSessions.get(userId).request(context); + } + } + +} -- cgit v1.2.3