GUAC-1105: Reduce code complexity of AbstractGuacamoleSocketService.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/socket/AbstractGuacamoleSocketService.java

@@ -44,7 +44,6 @@ import org.glyptodon.guacamole.GuacamoleSecurityException;
 import org.glyptodon.guacamole.auth.jdbc.connection.ConnectionMapper;
 import org.glyptodon.guacamole.environment.Environment;
 import org.glyptodon.guacamole.net.GuacamoleSocket;
-import org.glyptodon.guacamole.net.InetGuacamoleSocket;
 import org.glyptodon.guacamole.net.auth.Connection;
 import org.glyptodon.guacamole.net.auth.ConnectionGroup;
 import org.glyptodon.guacamole.net.auth.ConnectionRecord;
@@ -214,19 +213,17 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
     }
 
     /**
-     * Saves the given ActiveConnectionRecord to the database, associating it
+     * Saves the given ActiveConnectionRecord to the database. The end date of
-     * with the connection having the given identifier. The end date of the
+     * the saved record will be populated with the current time.
-     * saved record will be populated with the current time.
-     *
-     * @param identifier
-     *     The connection to associate the new record with.
      *
      * @param record
      *     The record to save.
      */
-    private void saveConnectionRecord(String identifier,
+    private void saveConnectionRecord(ActiveConnectionRecord record) {
-            ActiveConnectionRecord record) {
 
+        // Get associated connection
+        ModeledConnection connection = record.getConnection();
+        
         // Get associated models
         AuthenticatedUser user = record.getUser();
         UserModel userModel = user.getUser().getModel();
@@ -235,7 +232,7 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
         // Copy user information and timestamps into new record
         recordModel.setUserID(userModel.getObjectID());
         recordModel.setUsername(userModel.getIdentifier());
-        recordModel.setConnectionIdentifier(identifier);
+        recordModel.setConnectionIdentifier(connection.getIdentifier());
         recordModel.setStartDate(record.getStartDate());
         recordModel.setEndDate(new Date());
 
@@ -255,24 +252,88 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
      *     If an error occurs while connecting to guacd, or while parsing
      *     guacd-related properties.
      */
-    private GuacamoleSocket getUnconfiguredGuacamoleSocket()
+    private GuacamoleSocket getUnconfiguredGuacamoleSocket(Runnable socketClosedCallback)
         throws GuacamoleException {
 
         // Use SSL if requested
         if (environment.getProperty(Environment.GUACD_SSL, true))
-            return new InetGuacamoleSocket(
+            return new ManagedInetGuacamoleSocket(
                 environment.getRequiredProperty(Environment.GUACD_HOSTNAME),
-                environment.getRequiredProperty(Environment.GUACD_PORT)
+                environment.getRequiredProperty(Environment.GUACD_PORT),
+                socketClosedCallback
             );
 
         // Otherwise, just use straight TCP
-        return new InetGuacamoleSocket(
+        return new ManagedInetGuacamoleSocket(
             environment.getRequiredProperty(Environment.GUACD_HOSTNAME),
-            environment.getRequiredProperty(Environment.GUACD_PORT)
+            environment.getRequiredProperty(Environment.GUACD_PORT),
+            socketClosedCallback
         );
 
     }
-    
+
+    /**
+     * Task which handles cleanup of a connection associated with some given
+     * ActiveConnectionRecord.
+     */
+    private class ConnectionCleanupTask implements Runnable {
+
+        /**
+         * Whether this task has run.
+         */
+        private final AtomicBoolean hasRun = new AtomicBoolean(false);
+
+        /**
+         * The ActiveConnectionRecord whose connection will be cleaned up once
+         * this task runs.
+         */
+        private final ActiveConnectionRecord activeConnection;
+
+        /**
+         * Creates a new task which automatically cleans up after the
+         * connection associated with the given ActiveConnectionRecord. The
+         * connection and parent group will be removed from the maps of active
+         * connections and groups, and exclusive access will be released.
+         *
+         * @param activeConnection
+         *     The ActiveConnectionRecord whose associated connection should be
+         *     cleaned up once this task runs.
+         */
+        public ConnectionCleanupTask(ActiveConnectionRecord activeConnection) {
+            this.activeConnection = activeConnection;
+        }
+        
+        @Override
+        public void run() {
+
+            // Only run once
+            if (!hasRun.compareAndSet(false, true))
+                return;
+
+            // Get original user and connection
+            AuthenticatedUser user = activeConnection.getUser();
+            ModeledConnection connection = activeConnection.getConnection();
+
+            // Get associated identifiers
+            String identifier = connection.getIdentifier();
+            String parentIdentifier = connection.getParentIdentifier();
+
+            // Release connection
+            activeConnections.remove(identifier, activeConnection);
+            activeConnectionGroups.remove(parentIdentifier, activeConnection);
+            release(user, connection);
+
+            // Release any associated group
+            if (activeConnection.hasBalancingGroup())
+                release(user, activeConnection.getBalancingGroup());
+            
+            // Save history record to database
+            saveConnectionRecord(activeConnection);
+
+        }
+
+    }
+
     /**
      * Creates a socket for the given user which connects to the given
      * connection, which MUST already be acquired via acquire(). The given
@@ -285,11 +346,6 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
      * @param user
      *     The user for whom the connection is being established.
      *
-     * @param balancingGroup,
-     *     The associated balancing group, if any. If the connection is not
-     *     associated with a balancing group, or the connection is being used
-     *     manually, this will be null.
-     *
      * @param connection
      *     The connection the user is connecting to.
      *
@@ -305,85 +361,77 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
      *     If an error occurs while the connection is being established, or
      *     while connection configuration information is being retrieved.
      */
-    private GuacamoleSocket connect(final AuthenticatedUser user,
+    private GuacamoleSocket getGuacamoleSocket(ActiveConnectionRecord activeConnection,
-            final ModeledConnectionGroup balancingGroup,
+            GuacamoleClientInformation info)
-            final ModeledConnection connection, GuacamoleClientInformation info)
             throws GuacamoleException {
 
-        // Create record for active connection
+        ModeledConnection connection = activeConnection.getConnection();
-        final ActiveConnectionRecord activeConnection = new ActiveConnectionRecord(user);
+        
+        // Record new active connection
+        Runnable cleanupTask = new ConnectionCleanupTask(activeConnection);
+        activeConnections.put(connection.getIdentifier(), activeConnection);
+        activeConnectionGroups.put(connection.getParentIdentifier(), activeConnection);
 
-        // Get relevant identifiers
-        final AtomicBoolean released = new AtomicBoolean(false);
-        final String identifier = connection.getIdentifier();
-        final String parentIdentifier = connection.getParentIdentifier();
-    
         // Return new socket
         try {
-
-            // Record new active connection
-            activeConnections.put(identifier, activeConnection);
-            activeConnectionGroups.put(parentIdentifier, activeConnection);
-
-            // Return newly-reserved connection
             return new ConfiguredGuacamoleSocket(
-                getUnconfiguredGuacamoleSocket(),
+                getUnconfiguredGuacamoleSocket(cleanupTask),
-                getGuacamoleConfiguration(user, connection),
+                getGuacamoleConfiguration(activeConnection.getUser(), connection),
                 info
-            ) {
+            );
-
-                @Override
-                public void close() throws GuacamoleException {
-
-                    // Attempt to close connection
-                    super.close();
-                    
-                    // Release connection upon close, if not already released
-                    if (released.compareAndSet(false, true)) {
-
-                        // Release connection
-                        activeConnections.remove(identifier, activeConnection);
-                        activeConnectionGroups.remove(parentIdentifier, activeConnection);
-                        release(user, connection);
-
-                        // Release any associated group
-                        if (balancingGroup != null)
-                            release(user, balancingGroup);
-                        
-                        // Save record to database
-                        saveConnectionRecord(identifier, activeConnection);
-
-                    }
-                    
-                } // end close()
-                
-            };
-
         }
 
-        // Release connection in case of error
+        // Execute cleanup if socket could not be created
         catch (GuacamoleException e) {
-
+            cleanupTask.run();
-            // Release connection if not already released
-            if (released.compareAndSet(false, true)) {
-
-                // Release connection
-                activeConnections.remove(identifier, activeConnection);
-                activeConnectionGroups.remove(parentIdentifier, activeConnection);
-                release(user, connection);
-
-                // Release any associated group
-                if (balancingGroup != null)
-                    release(user, balancingGroup);
-                
-            }
-
             throw e;
-
         }
 
     }
 
+    /**
+     * Returns a list of all balanced connections within a given connection
+     * group. If the connection group is not balancing, or it contains no
+     * connections, an empty list is returned.
+     *
+     * @param user
+     *     The user on whose behalf the balanced connections within the given
+     *     connection group are being retrieved.
+     *
+     * @param connectionGroup
+     *     The connection group to retrieve the balanced connections of.
+     *
+     * @return
+     *     A list containing all balanced connections within the given group,
+     *     or an empty list if there are no such connections.
+     */
+    private List<ModeledConnection> getBalancedConnections(AuthenticatedUser user,
+            ModeledConnectionGroup connectionGroup) {
+
+        // If not a balancing group, there are no balanced connections
+        if (connectionGroup.getType() != ConnectionGroup.Type.BALANCING)
+            return Collections.EMPTY_LIST;
+
+        // If group has no children, there are no balanced connections
+        Collection<String> identifiers = connectionMapper.selectIdentifiersWithin(connectionGroup.getIdentifier());
+        if (identifiers.isEmpty())
+            return Collections.EMPTY_LIST;
+
+        // Retrieve all children
+        Collection<ConnectionModel> models = connectionMapper.select(identifiers);
+        List<ModeledConnection> connections = new ArrayList<ModeledConnection>(models.size());
+
+        // Convert each retrieved model to a modeled connection
+        for (ConnectionModel model : models) {
+            ModeledConnection connection = connectionProvider.get();
+            connection.init(user, model);
+            connections.add(connection);
+        }
+
+        return connections;
+        
+    }
+
     @Override
     @Transactional
     public GuacamoleSocket getGuacamoleSocket(final AuthenticatedUser user,
@@ -392,7 +440,7 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
 
         // Acquire and connect to single connection
         acquire(user, Collections.singletonList(connection));
-        return connect(user, null, connection, info);
+        return getGuacamoleSocket(new ActiveConnectionRecord(user, connection), info);
 
     }
 
@@ -407,32 +455,17 @@ public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketS
             ModeledConnectionGroup connectionGroup,
             GuacamoleClientInformation info) throws GuacamoleException {
 
-        // If not a balancing group, cannot connect
+        // If group has no associated balanced connections, cannot connect
-        if (connectionGroup.getType() != ConnectionGroup.Type.BALANCING)
+        List<ModeledConnection> connections = getBalancedConnections(user, connectionGroup);
-            throw new GuacamoleSecurityException("Permission denied.");
+        if (connections.isEmpty())
-        
-        // If group has no children, cannot connect
-        Collection<String> identifiers = connectionMapper.selectIdentifiersWithin(connectionGroup.getIdentifier());
-        if (identifiers.isEmpty())
             throw new GuacamoleSecurityException("Permission denied.");
 
         // Acquire group
         acquire(user, connectionGroup);
 
-        // Retrieve all children
-        Collection<ConnectionModel> models = connectionMapper.select(identifiers);
-        List<ModeledConnection> connections = new ArrayList<ModeledConnection>(models.size());
-
-        // Convert each retrieved model to a modeled connection
-        for (ConnectionModel model : models) {
-            ModeledConnection connection = connectionProvider.get();
-            connection.init(user, model);
-            connections.add(connection);
-        }
-
         // Acquire and connect to any child
         ModeledConnection connection = acquire(user, connections);
-        return connect(user, connectionGroup, connection, info);
+        return getGuacamoleSocket(new ActiveConnectionRecord(user, connectionGroup, connection), info);
 
     }
 

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/socket/ActiveConnectionRecord.java

@@ -23,6 +23,8 @@
 package org.glyptodon.guacamole.auth.jdbc.socket;
 
 import java.util.Date;
+import org.glyptodon.guacamole.auth.jdbc.connection.ModeledConnection;
+import org.glyptodon.guacamole.auth.jdbc.connectiongroup.ModeledConnectionGroup;
 import org.glyptodon.guacamole.auth.jdbc.user.AuthenticatedUser;
 import org.glyptodon.guacamole.net.auth.ConnectionRecord;
 
@@ -43,21 +45,62 @@ public class ActiveConnectionRecord implements ConnectionRecord {
      */
     private final AuthenticatedUser user;
 
+    /**
+     * The balancing group from which the associated connection was chosen, if
+     * any. If no balancing group was used, this will be null.
+     */
+    private final ModeledConnectionGroup balancingGroup;
+
+    /**
+     * The connection associated with this connection record.
+     */
+    private final ModeledConnection connection;
+
     /**
      * The time this connection record was created.
      */
     private final Date startDate = new Date();
 
     /**
-     * Creates a new connection record associated with the given user. The
+     * Creates a new connection record associated with the given user,
-     * start date of this connection record will be the time of its creation.
+     * connection, and balancing connection group. The given balancing
+     * connection group MUST be the connection group from which the given
+     * connection was chosen. The start date of this connection record will be
+     * the time of its creation.
      *
      * @param user
      *     The user that connected to the connection associated with this
      *     connection record.
+     *
+     * @param balancingGroup
+     *     The balancing group from which the given connection was chosen.
+     *
+     * @param connection
+     *     The connection to associate with this connection record.
      */
-    public ActiveConnectionRecord(AuthenticatedUser user) {
+    public ActiveConnectionRecord(AuthenticatedUser user,
+            ModeledConnectionGroup balancingGroup,
+            ModeledConnection connection) {
         this.user = user;
+        this.balancingGroup = balancingGroup;
+        this.connection = connection;
+    }
+
+    /**
+     * Creates a new connection record associated with the given user and
+     * connection. The start date of this connection record will be the time of
+     * its creation.
+     *
+     * @param user
+     *     The user that connected to the connection associated with this
+     *     connection record.
+     *
+     * @param connection
+     *     The connection to associate with this connection record.
+     */
+    public ActiveConnectionRecord(AuthenticatedUser user,
+            ModeledConnection connection) {
+        this(user, null, connection);
     }
 
     /**
@@ -72,6 +115,40 @@ public class ActiveConnectionRecord implements ConnectionRecord {
         return user;
     }
 
+    /**
+     * Returns the balancing group from which the connection associated with
+     * this connection record was chosen.
+     *
+     * @return
+     *     The balancing group from which the connection associated with this
+     *     connection record was chosen.
+     */
+    public ModeledConnectionGroup getBalancingGroup() {
+        return balancingGroup;
+    }
+
+    /**
+     * Returns the connection associated with this connection record.
+     *
+     * @return
+     *     The connection associated with this connection record.
+     */
+    public ModeledConnection getConnection() {
+        return connection;
+    }
+
+    /**
+     * Returns whether the connection associated with this connection record
+     * was chosen from a balancing group.
+     *
+     * @return
+     *     true if the connection associated with this connection record was
+     *     chosen from a balancing group, false otherwise.
+     */
+    public boolean hasBalancingGroup() {
+        return balancingGroup != null;
+    }
+    
     @Override
     public Date getStartDate() {
         return startDate;

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/socket/ManagedInetGuacamoleSocket.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2015 Glyptodon LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package org.glyptodon.guacamole.auth.jdbc.socket;
+
+import org.glyptodon.guacamole.GuacamoleException;
+import org.glyptodon.guacamole.net.InetGuacamoleSocket;
+
+/**
+ * Implementation of GuacamoleSocket which connects via TCP to a given hostname
+ * and port. If the socket is closed for any reason, a given task is run.
+ *
+ * @author Michael Jumper
+ */
+public class ManagedInetGuacamoleSocket extends InetGuacamoleSocket {
+
+    /**
+     * The task to run when the socket is closed.
+     */
+    private final Runnable socketClosedTask;
+
+    /**
+     * Creates a new socket which connects via TCP to a given hostname and
+     * port. If the socket is closed for any reason, the given task is run.
+     * 
+     * @param hostname
+     *     The hostname of the Guacamole proxy server to connect to.
+     *
+     * @param port
+     *     The port of the Guacamole proxy server to connect to.
+     *
+     * @param socketClosedTask
+     *     The task to run when the socket is closed. This task will NOT be
+     *     run if an exception occurs during connection, and this
+     *     ManagedInetGuacamoleSocket instance is ultimately not created.
+     *
+     * @throws GuacamoleException
+     *     If an error occurs while connecting to the Guacamole proxy server.
+     */
+    public ManagedInetGuacamoleSocket(String hostname, int port,
+            Runnable socketClosedTask) throws GuacamoleException {
+        super(hostname, port);
+        this.socketClosedTask = socketClosedTask;
+    }
+
+    @Override
+    public void close() throws GuacamoleException {
+        super.close();
+        socketClosedTask.run();
+    }
+    
+}