GUACAMOLE-1224: Add user session invalidation/logout event.

guacamole-ext/src/main/java/org/apache/guacamole/net/event/UserSessionInvalidatedEvent.java

@@ -0,0 +1,27 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.apache.guacamole.net.event;
+
+/**
+ * Event that is dispatched when a user has logged out or their session has
+ * expired.
+ */
+public interface UserSessionInvalidatedEvent extends UserEvent {
+}

guacamole/src/main/java/org/apache/guacamole/GuacamoleSession.java

@@ -23,12 +23,13 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
-import org.apache.guacamole.environment.Environment;
 import org.apache.guacamole.net.GuacamoleTunnel;
 import org.apache.guacamole.net.auth.AuthenticatedUser;
 import org.apache.guacamole.net.auth.AuthenticationProvider;
 import org.apache.guacamole.net.auth.UserContext;
+import org.apache.guacamole.net.event.UserSessionInvalidatedEvent;
 import org.apache.guacamole.rest.auth.DecoratedUserContext;
+import org.apache.guacamole.rest.event.ListenerService;
 import org.apache.guacamole.tunnel.UserTunnel;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -58,8 +59,12 @@ public class GuacamoleSession {
     /**
      * All currently-active tunnels, indexed by tunnel UUID.
      */
-    private final Map<String, UserTunnel> tunnels =
-            new ConcurrentHashMap<String, UserTunnel>();
+    private final Map<String, UserTunnel> tunnels = new ConcurrentHashMap<>();
+
+    /**
+     * Service for dispatching events to registered event listeners.
+     */
+    private final ListenerService listenerService;
 
     /**
      * The last time this session was accessed.
@@ -70,9 +75,9 @@ public class GuacamoleSession {
      * Creates a new Guacamole session associated with the given
      * AuthenticatedUser and UserContexts.
      *
-     * @param environment
-     *     The environment of the Guacamole server associated with this new
-     *     session.
+     * @param listenerService
+     *     The service to use to notify registered event listeners when this
+     *     session is invalidated.
      *
      * @param authenticatedUser
      *     The authenticated user to associate this session with.
@@ -83,11 +88,12 @@ public class GuacamoleSession {
      * @throws GuacamoleException
      *     If an error prevents the session from being created.
      */
-    public GuacamoleSession(Environment environment,
+    public GuacamoleSession(ListenerService listenerService,
             AuthenticatedUser authenticatedUser,
             List<DecoratedUserContext> userContexts)
             throws GuacamoleException {
         this.lastAccessedTime = System.currentTimeMillis();
+        this.listenerService = listenerService;
         this.authenticatedUser = authenticatedUser;
         this.userContexts = userContexts;
     }
@@ -260,6 +266,23 @@ public class GuacamoleSession {
         // Invalidate the authenticated user object
         authenticatedUser.invalidate();
 
+        // Advise any registered listeners that the user's session is now
+        // invalidated
+        try {
+            listenerService.handleEvent(new UserSessionInvalidatedEvent() {
+
+                @Override
+                public AuthenticatedUser getAuthenticatedUser() {
+                    return authenticatedUser;
+                }
+
+            });
+        }
+        catch (GuacamoleException e) {
+            logger.error("An extension listening for session invalidation failed: {}", e.getMessage());
+            logger.debug("Extension failed internally while handling the session invalidation event.", e);
+        }
+
     }
     
 }

guacamole/src/main/java/org/apache/guacamole/event/EventLoggingListener.java

@@ -27,6 +27,7 @@ import org.apache.guacamole.net.event.ApplicationStartedEvent;
 import org.apache.guacamole.net.event.DirectoryEvent;
 import org.apache.guacamole.net.event.DirectoryFailureEvent;
 import org.apache.guacamole.net.event.DirectorySuccessEvent;
+import org.apache.guacamole.net.event.UserSessionInvalidatedEvent;
 import org.apache.guacamole.net.event.listener.Listener;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -123,6 +124,11 @@ public class EventLoggingListener implements Listener {
         else if (event instanceof DirectoryFailureEvent)
             logFailure((DirectoryFailureEvent<?>) event);
 
+        // Logout / session expiration
+        else if (event instanceof UserSessionInvalidatedEvent)
+            logger.info("{} has logged out, or their session has expired or "
+                    + "been terminated.", new RequestingUser((UserSessionInvalidatedEvent) event));
+
         // Application startup/shutdown
         else if (event instanceof ApplicationStartedEvent)
             logger.info("The Apache Guacamole web application has started.");

guacamole/src/main/java/org/apache/guacamole/event/RequestingUser.java

@@ -20,7 +20,7 @@
 package org.apache.guacamole.event;
 
 import org.apache.guacamole.net.auth.AuthenticatedUser;
-import org.apache.guacamole.net.event.DirectoryEvent;
+import org.apache.guacamole.net.event.UserEvent;
 
 /**
  * Loggable representation of the user that requested an operation.
@@ -30,7 +30,7 @@ public class RequestingUser implements LoggableDetail {
     /**
      * The event representing the requested operation.
      */
-    private final DirectoryEvent<?> event;
+    private final UserEvent event;
 
     /**
      * Creates a new RequestingUser that represents the user that requested the
@@ -39,7 +39,7 @@ public class RequestingUser implements LoggableDetail {
      * @param event
      *     The event representing the requested operation.
      */
-    public RequestingUser(DirectoryEvent<?> event) {
+    public RequestingUser(UserEvent event) {
         this.event = event;
     }
 

guacamole/src/main/java/org/apache/guacamole/rest/auth/AuthenticationService.java

@@ -30,7 +30,6 @@ import org.apache.guacamole.GuacamoleSecurityException;
 import org.apache.guacamole.GuacamoleServerException;
 import org.apache.guacamole.GuacamoleUnauthorizedException;
 import org.apache.guacamole.GuacamoleSession;
-import org.apache.guacamole.environment.Environment;
 import org.apache.guacamole.net.auth.AuthenticatedUser;
 import org.apache.guacamole.net.auth.AuthenticationProvider;
 import org.apache.guacamole.net.auth.Credentials;
@@ -56,12 +55,6 @@ public class AuthenticationService {
      */
     private static final Logger logger = LoggerFactory.getLogger(AuthenticationService.class);
 
-    /**
-     * The Guacamole server environment.
-     */
-    @Inject
-    private Environment environment;
-
     /**
      * All configured authentication providers which can be used to
      * authenticate users or retrieve data associated with authenticated users.
@@ -443,7 +436,7 @@ public class AuthenticationService {
             // If no existing session, generate a new token/session pair
             else {
                 authToken = authTokenGenerator.getToken();
-                tokenSessionMap.put(authToken, new GuacamoleSession(environment, authenticatedUser, userContexts));
+                tokenSessionMap.put(authToken, new GuacamoleSession(listenerService, authenticatedUser, userContexts));
                 logger.debug("Login was successful for user \"{}\".", authenticatedUser.getIdentifier());
             }