IDEMPIERE-5049 Zk Session and Desktop object not destroy immediately after logout (#994)

- Remove 5 second delay for remove of desktop after logout
- added X-PING custom http header for "ping" to index.zul
- added watch for disconnected desktop

org.adempiere.ui.zk/WEB-INF/src/fi/jawsy/jawwa/zk/atmosphere/AtmosphereServerPush.java

@@ -301,6 +301,14 @@ public class AtmosphereServerPush implements ServerPush {
 		startClientPush(desktop.get());
 	}
 	
+	/**
+	 * 
+	 * @return true if it is holding an atmosphere resource
+	 */
+	public boolean hasAtmosphereResource() {
+		return this.resource.get() != null;
+	}
+	
 	private class Schedule<T extends Event> {
     	private EventListener<T> task;
 		private T event;

org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/AdempiereWebUI.java

@@ -44,6 +44,7 @@ import org.adempiere.webui.session.SessionManager;
 import org.adempiere.webui.theme.ITheme;
 import org.adempiere.webui.theme.ThemeManager;
 import org.adempiere.webui.util.BrowserToken;
+import org.adempiere.webui.util.DesktopWatchDog;
 import org.adempiere.webui.util.UserPreference;
 import org.compiere.Adempiere;
 import org.compiere.model.MRole;
@@ -140,12 +141,20 @@ public class AdempiereWebUI extends Window implements EventListener<Event>, IWeb
 
 	public void onCreate()
     {
-        this.getPage().setTitle(ThemeManager.getBrowserTitle());
+		String ping = Executions.getCurrent().getHeader("X-PING");
+		if (!Util.isEmpty(ping, true))
+		{
+			cleanupForPing();
+	        return;
+		}
+		
+		this.getPage().setTitle(ThemeManager.getBrowserTitle());
         
         Executions.getCurrent().getDesktop().enableServerPush(true);
+        DesktopWatchDog.addDesktop(Executions.getCurrent().getDesktop());
         
         SessionManager.setSessionApplication(this);
-        Session session = Executions.getCurrent().getDesktop().getSession();
+        final Session session = Executions.getCurrent().getDesktop().getSession();
         
         Properties ctx = Env.getCtx();
         langSession = Env.getContext(ctx, Env.LANGUAGE);
@@ -174,6 +183,25 @@ public class AdempiereWebUI extends Window implements EventListener<Event>, IWeb
         eventThreadEnabled = Executions.getCurrent().getDesktop().getWebApp().getConfiguration().isEventThreadEnabled();        
     }
 
+	private void cleanupForPing() {
+		final Desktop desktop = Executions.getCurrent().getDesktop();
+		final WebApp wapp = desktop.getWebApp();
+		final DesktopCache desktopCache = ((WebAppCtrl) wapp).getDesktopCache(desktop.getSession());	    	    
+		final Session session = desktop.getSession();
+		
+		//clear context, invalidate session
+		Env.getCtx().clear();
+		destroySession(session);
+		desktop.setAttribute(DESKTOP_SESSION_INVALIDATED_ATTR, Boolean.TRUE);
+		Adempiere.getThreadPoolExecutor().schedule(() -> {
+		    try {
+				desktopCache.removeDesktop(desktop);
+			} catch (Throwable t) {
+				t.printStackTrace();
+			}
+		}, 1, TimeUnit.SECONDS);
+	}
+
     public void onOk()
     {
     }
@@ -386,14 +414,6 @@ public class AdempiereWebUI extends Window implements EventListener<Event>, IWeb
     	
 	    final WebApp wapp = desktop.getWebApp();
 	    final DesktopCache desktopCache = ((WebAppCtrl) wapp).getDesktopCache(desktop.getSession());	    	    
-	    Adempiere.getThreadPoolExecutor().schedule(() -> {
-	    	try {
-	    		desktopCache.removeDesktop(desktop);
-	    	} catch (Throwable t) {
-	    		t.printStackTrace();
-	    	}	    	
-	    }, 5, TimeUnit.SECONDS);
-	    
 	    final Session session = logout0();
 	    
     	//clear context, invalidate session
@@ -403,6 +423,13 @@ public class AdempiereWebUI extends Window implements EventListener<Event>, IWeb
             	
         //redirect to login page
         Executions.sendRedirect("index.zul");       
+        
+        try {
+    		desktopCache.removeDesktop(desktop);
+    		DesktopWatchDog.removeDesktop(desktop);
+    	} catch (Throwable t) {
+    		t.printStackTrace();
+    	}
     }
 
 	private void destroySession(final Session session) {
@@ -414,10 +441,14 @@ public class AdempiereWebUI extends Window implements EventListener<Event>, IWeb
     	session.invalidate();
 	}
     
+	/**
+	 * Perform logout after user close a browser tab without first logging out
+	 */
     public void logoutAfterTabDestroyed(){
     	Desktop desktop = Executions.getCurrent().getDesktop();
 	    if (desktop.isServerPushEnabled())
 			desktop.enableServerPush(false);
+	    DesktopWatchDog.removeDesktop(desktop);
 	    
        	Session session = logout0();
 

org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/WLogin.java

@@ -63,23 +63,6 @@ public class WLogin extends AbstractUIPart
         loginWindow = (LoginWindow) loginPage.getFellow("loginWindow");
         loginWindow.init(app);
 
-        /* IDEMPIERE-1022 - deprecated message
-        if (!AEnv.isBrowserSupported())
-        {
-        	//TODO: localization
-        	String msg = "You might experience slow performance and user interface anomalies using your current browser to access the application. We recommend the use of Firefox, Google Chrome or Apple Safari.";
-        	browserWarningWindow = new Window();
-        	Div div = new Div();
-        	div.setStyle("font-size: 9pt");
-        	div.appendChild(new Text(msg));
-        	browserWarningWindow.appendChild(div);
-        	browserWarningWindow.setPosition("top,right");
-        	ZKUpdateUtil.setWidth(browserWarningWindow, "550px");
-        	browserWarningWindow.setPage(page);
-        	browserWarningWindow.doOverlapped();
-        }
-        */
-        
         boolean mobile = false;        
 		if (Executions.getCurrent().getBrowser("mobile") !=null) {
 			mobile = true;

org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/session/SessionManager.java

@@ -85,6 +85,10 @@ public class SessionManager
     		app.logout();
     }
     
+    /**
+	 * Perform logout after user close a browser tab without first logging out.
+	 * Usually this is invoke from {@link SessionContextListener} and developer shouldn't call this directly.
+	 */
     public static void logoutSessionAfterBrowserDestroyed()
     {
     	IWebClient app = getSessionApplication();
@@ -92,6 +96,10 @@ public class SessionManager
     		app.logoutAfterTabDestroyed();
     }
     
+    /**
+     * 
+     * @param user
+     */
     public static void changeRole(MUser user){
     	IWebClient app = getSessionApplication();
     	if (app != null)

org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/util/DesktopWatchDog.java

@@ -0,0 +1,149 @@
+/***********************************************************************
+ * This file is part of iDempiere ERP Open Source                      *
+ * http://www.idempiere.org                                            *
+ *                                                                     *
+ * Copyright (C) Contributors                                          *
+ *                                                                     *
+ * This program is free software; you can redistribute it and/or       *
+ * modify it under the terms of the GNU General Public License         *
+ * as published by the Free Software Foundation; either version 2      *
+ * of the License, or (at your option) any later version.              *
+ *                                                                     *
+ * This program is distributed in the hope that it will be useful,     *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of      *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the        *
+ * GNU General Public License for more details.                        *
+ *                                                                     *
+ * You should have received a copy of the GNU General Public License   *
+ * along with this program; if not, write to the Free Software         *
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,          *
+ * MA 02110-1301, USA.                                                 *
+ *                                                                     *
+ * Contributors:                                                       *
+ * - hengsin                         								   *
+ **********************************************************************/
+package org.adempiere.webui.util;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.concurrent.ConcurrentLinkedDeque;
+import java.util.concurrent.TimeUnit;
+
+import org.compiere.Adempiere;
+import org.zkoss.zk.ui.Desktop;
+import org.zkoss.zk.ui.Session;
+import org.zkoss.zk.ui.WebApp;
+import org.zkoss.zk.ui.sys.DesktopCache;
+import org.zkoss.zk.ui.sys.DesktopCtrl;
+import org.zkoss.zk.ui.sys.ServerPush;
+import org.zkoss.zk.ui.sys.SessionCtrl;
+import org.zkoss.zk.ui.sys.WebAppCtrl;
+
+import fi.jawsy.jawwa.zk.atmosphere.AtmosphereServerPush;
+
+/**
+ * watch for disconnected desktop and destroy it
+ * @author hengsin
+ *
+ */
+public class DesktopWatchDog {
+
+	private final static DesktopWatchDog INSTANCE = new DesktopWatchDog();
+	
+	private final ConcurrentLinkedDeque<DesktopEntry> desktops = new ConcurrentLinkedDeque<DesktopWatchDog.DesktopEntry>();
+	
+	private DesktopWatchDog() {
+		Adempiere.getThreadPoolExecutor().scheduleWithFixedDelay(() -> {
+			doMonitoring();
+		}, 60, 40, TimeUnit.SECONDS);
+	}
+
+	private void doMonitoring() {
+		List<Session> toDestroy = new ArrayList<Session>();
+		List<Session> actives = new ArrayList<Session>();
+		Iterator<DesktopEntry> iterator = desktops.iterator();
+		while (iterator.hasNext()) {
+			DesktopEntry entry = iterator.next();
+			if (!entry.desktop.isAlive()) {
+				iterator.remove();
+				continue;
+			}
+			if (entry.desktop.isServerPushEnabled() == false) {
+				entry.noAtmosphereResourceCount++;
+			}
+			ServerPush spush = ((DesktopCtrl)entry.desktop).getServerPush();
+			if (spush == null) {
+				entry.noAtmosphereResourceCount++;
+			} else if (spush instanceof AtmosphereServerPush) {
+				AtmosphereServerPush asp = (AtmosphereServerPush) spush;
+				if (!asp.hasAtmosphereResource())
+					entry.noAtmosphereResourceCount++;
+				else
+					entry.noAtmosphereResourceCount=0;
+			}
+			if (entry.noAtmosphereResourceCount >= 3) {
+				iterator.remove();
+		        try {
+		        	final WebApp wapp = entry.desktop.getWebApp();
+		        	final Session session = entry.desktop.getSession();
+		    	    final DesktopCache desktopCache = ((WebAppCtrl) wapp).getDesktopCache(session);
+		    		desktopCache.removeDesktop(entry.desktop);
+		    		if (!actives.contains(session) && !toDestroy.contains(session))
+		    			toDestroy.add(session);
+		    	} catch (Throwable t) {
+		    		t.printStackTrace();
+		    	}
+			} else {
+				final Session session = entry.desktop.getSession();
+				if (!actives.contains(session))
+					actives.add(session);
+				int index = toDestroy.indexOf(session);
+				if (index >= 0)
+					toDestroy.remove(index);
+			}
+		}
+		if (!toDestroy.isEmpty()) {
+			for(Session session : toDestroy) {
+				try {
+		    		((SessionCtrl)session).onDestroyed();
+		    	} catch (Throwable t) {
+		    		t.printStackTrace();
+		    	}
+		    	session.invalidate();
+			}
+		}
+	}
+
+	private final static class DesktopEntry {		
+		Desktop desktop;
+		int noAtmosphereResourceCount = 0;
+		
+		private DesktopEntry(Desktop desktop) {
+			this.desktop = desktop;
+		}
+	}
+	
+	/**
+	 * add desktop to watch list
+	 * @param desktop
+	 */
+	public static void addDesktop(Desktop desktop) {
+		INSTANCE.desktops.add(new DesktopEntry(desktop));
+	}
+	
+	/**
+	 * remove desktop from watch list
+	 * @param desktop
+	 */
+	public static void removeDesktop(Desktop desktop) {
+		Iterator<DesktopEntry> iterator = INSTANCE.desktops.iterator();
+		while (iterator.hasNext()) {
+			DesktopEntry entry = iterator.next();
+			if (entry.desktop == desktop) {
+				iterator.remove();
+				break;
+			}
+		}
+	}
+}