HG UAS: Moved hg-session data from memory to DB storage. This makes it so that traveling info survives Robust resets. It should also eliminate the cause of empty IP addresses in agent circuit data that we saw in CC grid. MySQL only.

5 files changed, 344 insertions, 90 deletions

diff --git a/OpenSim/Data/IHGTravelingData.cs b/OpenSim/Data/IHGTravelingData.cs
new file mode 100644
index 0000000..dd89935
--- /dev/null
+++ b/OpenSim/Data/IHGTravelingData.cs
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using OpenMetaverse;
+using OpenSim.Framework;
+
+namespace OpenSim.Data
+{
+    // This MUST be a ref type!
+    public class HGTravelingData
+    {
+        public UUID SessionID;
+        public UUID UserID;
+        public Dictionary<string, string> Data;
+
+        public HGTravelingData()
+        {
+            Data = new Dictionary<string, string>();
+        }
+    }
+
+    /// <summary>
+    /// An interface for connecting to the user grid datastore
+    /// </summary>
+    public interface IHGTravelingData 
+    {
+        HGTravelingData Get(UUID sessionID);
+        HGTravelingData[] GetSessions(UUID userID);
+        bool Store(HGTravelingData data);
+        bool Delete(UUID sessionID);
+    }
+}
\ No newline at end of file
diff --git a/OpenSim/Data/MySQL/MySQLHGTravelData.cs b/OpenSim/Data/MySQL/MySQLHGTravelData.cs
new file mode 100644
index 0000000..1efbfc3
--- /dev/null
+++ b/OpenSim/Data/MySQL/MySQLHGTravelData.cs
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Reflection;
+using System.Threading;
+using log4net;
+using OpenMetaverse;
+using OpenSim.Framework;
+using MySql.Data.MySqlClient;
+
+namespace OpenSim.Data.MySQL
+{
+    /// <summary>
+    /// A MySQL Interface for user grid data
+    /// </summary>
+    public class MySQLHGTravelData : MySQLGenericTableHandler<HGTravelingData>, IHGTravelingData
+    {
+//        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
+
+        public MySQLHGTravelData(string connectionString, string realm) : base(connectionString, realm, "HGTravelStore") { }
+
+        public HGTravelingData Get(UUID sessionID)
+        {
+            HGTravelingData[] ret = Get("SessionID", sessionID.ToString());
+
+            if (ret.Length == 0)
+                return null;
+
+            return ret[0];
+        }
+
+        public HGTravelingData[] GetSessions(UUID userID)
+        {
+            return base.Get("UserID", userID.ToString());
+        }
+
+        public bool Delete(UUID sessionID)
+        {
+            return Delete("SessionID", sessionID.ToString());
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/OpenSim/Data/MySQL/Resources/HGTravelStore.migrations b/OpenSim/Data/MySQL/Resources/HGTravelStore.migrations
new file mode 100644
index 0000000..a0c9ebe
--- /dev/null
+++ b/OpenSim/Data/MySQL/Resources/HGTravelStore.migrations
@@ -0,0 +1,17 @@
+:VERSION 1         # -------------------------- 
+
+BEGIN;
+
+CREATE TABLE `hg_traveling_data` (
+    `SessionID` VARCHAR(36) NOT NULL,
+    `UserID` VARCHAR(36) NOT NULL,
+        `GridExternalName` VARCHAR(255) NOT NULL DEFAULT '',
+        `ServiceToken` VARCHAR(255) NOT NULL DEFAULT '',
+        `ClientIPAddress` VARCHAR(16) NOT NULL DEFAULT '',
+        `MyIPAddress` VARCHAR(16) NOT NULL DEFAULT '',
+    PRIMARY KEY  (`SessionID`),
+        KEY (`UserID`)
+) ENGINE=InnoDB;
+
+COMMIT;
+
diff --git a/OpenSim/Services/HypergridService/UserAgentService.cs b/OpenSim/Services/HypergridService/UserAgentService.cs
index 733993f..b597cb9 100644
--- a/OpenSim/Services/HypergridService/UserAgentService.cs
+++ b/OpenSim/Services/HypergridService/UserAgentService.cs
@@ -30,6 +30,7 @@ using System.Collections.Generic;
 using System.Net;
 using System.Reflection;
 
+using OpenSim.Data;
 using OpenSim.Framework;
 using OpenSim.Services.Connectors.Friends;
 using OpenSim.Services.Connectors.Hypergrid;
@@ -50,14 +51,14 @@ namespace OpenSim.Services.HypergridService
     /// needs to do it for them.
     /// Once we have better clients, this shouldn't be needed.
     /// </summary>
-    public class UserAgentService : IUserAgentService
+    public class UserAgentService : UserAgentServiceBase, IUserAgentService
     {
         private static readonly ILog m_log =
                 LogManager.GetLogger(
                 MethodBase.GetCurrentMethod().DeclaringType);
 
         // This will need to go into a DB table
-        static Dictionary<UUID, TravelingAgentInfo> m_TravelingAgents = new Dictionary<UUID, TravelingAgentInfo>();
+        //static Dictionary<UUID, TravelingAgentInfo> m_Database = new Dictionary<UUID, TravelingAgentInfo>();
 
         static bool m_Initialized = false;
 
@@ -86,6 +87,7 @@ namespace OpenSim.Services.HypergridService
         }
 
         public UserAgentService(IConfigSource config, IFriendsSimConnector friendsConnector)
+            : base(config)
         {
             // Let's set this always, because we don't know the sequence
             // of instantiations
@@ -260,7 +262,8 @@ namespace OpenSim.Services.HypergridService
 
             // Generate a new service session
             agentCircuit.ServiceSessionID = region.ServerURI + ";" + UUID.Random();
-            TravelingAgentInfo old = UpdateTravelInfo(agentCircuit, region);
+            TravelingAgentInfo old = null;
+            TravelingAgentInfo travel = CreateTravelInfo(agentCircuit, region, fromLogin, out old);
             
             bool success = false;
             string myExternalIP = string.Empty;
@@ -282,23 +285,21 @@ namespace OpenSim.Services.HypergridService
                 m_log.DebugFormat("[USER AGENT SERVICE]: Unable to login user {0} {1} to grid {2}, reason: {3}", 
                     agentCircuit.firstname, agentCircuit.lastname, region.ServerURI, reason);
 
-                // restore the old travel info
-                lock (m_TravelingAgents)
-                {
-                    if (old == null)
-                        m_TravelingAgents.Remove(agentCircuit.SessionID);
-                    else
-                        m_TravelingAgents[agentCircuit.SessionID] = old;
-                }
+                if (old != null)
+                    StoreTravelInfo(old);
+                else
+                    m_Database.Delete(agentCircuit.SessionID);
 
                 return false;
             }
 
+            // Everything is ok
+
+            // Update the perceived IP Address of our grid 
             m_log.DebugFormat("[USER AGENT SERVICE]: Gatekeeper sees me as {0}", myExternalIP);
-            // else set the IP addresses associated with this client
-            if (fromLogin)
-                m_TravelingAgents[agentCircuit.SessionID].ClientIPAddress = agentCircuit.IPAddress;
-            m_TravelingAgents[agentCircuit.SessionID].MyIpAddress = myExternalIP;
+            travel.MyIpAddress = myExternalIP;
+
+            StoreTravelInfo(travel);
 
             return true;
         }
@@ -309,57 +310,39 @@ namespace OpenSim.Services.HypergridService
             return LoginAgentToGrid(agentCircuit, gatekeeper, finalDestination, false, out reason);
         }
 
-        private void SetClientIP(UUID sessionID, string ip)
+        TravelingAgentInfo CreateTravelInfo(AgentCircuitData agentCircuit, GridRegion region, bool fromLogin, out TravelingAgentInfo existing)
         {
-            if (m_TravelingAgents.ContainsKey(sessionID))
-            {
-                m_log.DebugFormat("[USER AGENT SERVICE]: Setting IP {0} for session {1}", ip, sessionID);
-                m_TravelingAgents[sessionID].ClientIPAddress = ip;
-            }
-        }
+            HGTravelingData hgt = m_Database.Get(agentCircuit.SessionID);
+            existing = null;
 
-        TravelingAgentInfo UpdateTravelInfo(AgentCircuitData agentCircuit, GridRegion region)
-        {
-            TravelingAgentInfo travel = new TravelingAgentInfo();
-            TravelingAgentInfo old = null;
-            lock (m_TravelingAgents)
+            if (hgt != null)
             {
-                if (m_TravelingAgents.ContainsKey(agentCircuit.SessionID))
-                {
-                    // Very important! Override whatever this agent comes with.
-                    // UserAgentService always sets the IP for every new agent
-                    // with the original IP address.
-                    agentCircuit.IPAddress = m_TravelingAgents[agentCircuit.SessionID].ClientIPAddress;
-
-                    old = m_TravelingAgents[agentCircuit.SessionID];
-                }
-
-                m_TravelingAgents[agentCircuit.SessionID] = travel;
+                // Very important! Override whatever this agent comes with.
+                // UserAgentService always sets the IP for every new agent
+                // with the original IP address.
+                existing = new TravelingAgentInfo(hgt);
+                agentCircuit.IPAddress = existing.ClientIPAddress;
             }
+
+            TravelingAgentInfo travel = new TravelingAgentInfo(existing);
+            travel.SessionID = agentCircuit.SessionID;
             travel.UserID = agentCircuit.AgentID;
             travel.GridExternalName = region.ServerURI;
             travel.ServiceToken = agentCircuit.ServiceSessionID;
-            if (old != null)
-                travel.ClientIPAddress = old.ClientIPAddress;
 
-            return old;
+            if (fromLogin)
+                travel.ClientIPAddress = agentCircuit.IPAddress;
+
+            StoreTravelInfo(travel);
+
+            return travel;
         }
 
         public void LogoutAgent(UUID userID, UUID sessionID)
         {
             m_log.DebugFormat("[USER AGENT SERVICE]: User {0} logged out", userID);
 
-            lock (m_TravelingAgents)
-            {
-                List<UUID> travels = new List<UUID>();
-                foreach (KeyValuePair<UUID, TravelingAgentInfo> kvp in m_TravelingAgents)
-                    if (kvp.Value == null) // do some clean up
-                        travels.Add(kvp.Key);
-                    else if (kvp.Value.UserID == userID)
-                        travels.Add(kvp.Key);
-                foreach (UUID session in travels)
-                    m_TravelingAgents.Remove(session);
-            }
+            m_Database.Delete(sessionID);
 
             GridUserInfo guinfo = m_GridUserService.GetGridUserInfo(userID.ToString());
             if (guinfo != null)
@@ -369,10 +352,11 @@ namespace OpenSim.Services.HypergridService
         // We need to prevent foreign users with the same UUID as a local user
         public bool IsAgentComingHome(UUID sessionID, string thisGridExternalName)
         {
-            if (!m_TravelingAgents.ContainsKey(sessionID))
+            HGTravelingData hgt = m_Database.Get(sessionID);
+            if (hgt == null)
                 return false;
 
-            TravelingAgentInfo travel = m_TravelingAgents[sessionID];
+            TravelingAgentInfo travel = new TravelingAgentInfo(hgt);
 
             return travel.GridExternalName.ToLower() == thisGridExternalName.ToLower();
         }
@@ -385,31 +369,32 @@ namespace OpenSim.Services.HypergridService
             m_log.DebugFormat("[USER AGENT SERVICE]: Verifying Client session {0} with reported IP {1}.", 
                 sessionID, reportedIP);
 
-            if (m_TravelingAgents.ContainsKey(sessionID))
-            {
-                bool result = m_TravelingAgents[sessionID].ClientIPAddress == reportedIP ||
-                    m_TravelingAgents[sessionID].MyIpAddress == reportedIP; // NATed
+            HGTravelingData hgt = m_Database.Get(sessionID);
+            if (hgt == null)
+                return false;
 
-                m_log.DebugFormat("[USER AGENT SERVICE]: Comparing {0} with login IP {1} and MyIP {1}; result is {3}",
-                                    reportedIP, m_TravelingAgents[sessionID].ClientIPAddress, m_TravelingAgents[sessionID].MyIpAddress, result);
+            TravelingAgentInfo travel = new TravelingAgentInfo(hgt);
 
-                return result;
-            }
+            bool result = travel.ClientIPAddress == reportedIP || travel.MyIpAddress == reportedIP; // NATed
 
-            return false;
+            m_log.DebugFormat("[USER AGENT SERVICE]: Comparing {0} with login IP {1} and MyIP {1}; result is {3}",
+                                reportedIP, travel.ClientIPAddress, travel.MyIpAddress, result);
+
+            return result;
         }
 
         public bool VerifyAgent(UUID sessionID, string token)
         {
-            if (m_TravelingAgents.ContainsKey(sessionID))
+            HGTravelingData hgt = m_Database.Get(sessionID);
+            if (hgt == null)
             {
-                m_log.DebugFormat("[USER AGENT SERVICE]: Verifying agent token {0} against {1}", token, m_TravelingAgents[sessionID].ServiceToken);
-                return m_TravelingAgents[sessionID].ServiceToken == token;
+                m_log.DebugFormat("[USER AGENT SERVICE]: Token verification for session {0}: no such session", sessionID);
+                return false;
             }
 
-            m_log.DebugFormat("[USER AGENT SERVICE]: Token verification for session {0}: no such session", sessionID);
-
-            return false;
+            TravelingAgentInfo travel = new TravelingAgentInfo(hgt);
+            m_log.DebugFormat("[USER AGENT SERVICE]: Verifying agent token {0} against {1}", token, travel.ServiceToken);
+            return travel.ServiceToken == token;
         }
 
         [Obsolete]
@@ -472,17 +457,17 @@ namespace OpenSim.Services.HypergridService
                 }
             }
 
-            // Lastly, let's notify the rest who may be online somewhere else
-            foreach (string user in usersToBeNotified)
-            {
-                UUID id = new UUID(user);
-                if (m_TravelingAgents.ContainsKey(id) && m_TravelingAgents[id].GridExternalName != m_GridName)
-                {
-                    string url = m_TravelingAgents[id].GridExternalName;
-                    // forward
-                    m_log.WarnFormat("[USER AGENT SERVICE]: User {0} is visiting {1}. HG Status notifications still not implemented.", user, url);
-                }
-            }
+            //// Lastly, let's notify the rest who may be online somewhere else
+            //foreach (string user in usersToBeNotified)
+            //{
+            //    UUID id = new UUID(user);
+            //    if (m_Database.ContainsKey(id) && m_Database[id].GridExternalName != m_GridName)
+            //    {
+            //        string url = m_Database[id].GridExternalName;
+            //        // forward
+            //        m_log.WarnFormat("[USER AGENT SERVICE]: User {0} is visiting {1}. HG Status notifications still not implemented.", user, url);
+            //    }
+            //}
 
             // and finally, let's send the online friends
             if (online)
@@ -609,16 +594,13 @@ namespace OpenSim.Services.HypergridService
 
         public string LocateUser(UUID userID)
         {
-            foreach (TravelingAgentInfo t in m_TravelingAgents.Values)
-            {
-                if (t == null)
-                {
-                    m_log.ErrorFormat("[USER AGENT SERVICE]: Oops! Null TravelingAgentInfo. Please report this on mantis");
-                    continue;
-                }
-                if (t.UserID == userID && !m_GridName.Equals(t.GridExternalName))
-                    return t.GridExternalName;
-            }
+            HGTravelingData[] hgts = m_Database.GetSessions(userID);
+            if (hgts == null)
+                return string.Empty;
+
+            foreach (HGTravelingData t in hgts)
+                if (t.Data.ContainsKey("GridExternalName") && !m_GridName.Equals(t.Data["GridExternalName"]))
+                    return t.Data["GridExternalName"];
 
             return string.Empty;
         }
@@ -689,17 +671,60 @@ namespace OpenSim.Services.HypergridService
             return exception;
         }
 
+        private void StoreTravelInfo(TravelingAgentInfo travel)
+        {
+            if (travel == null)
+                return;
+
+            HGTravelingData hgt = new HGTravelingData();
+            hgt.SessionID = travel.SessionID;
+            hgt.UserID = travel.UserID;
+            hgt.Data = new Dictionary<string, string>();
+            hgt.Data["GridExternalName"] = travel.GridExternalName;
+            hgt.Data["ServiceToken"] = travel.ServiceToken;
+            hgt.Data["ClientIPAddress"] = travel.ClientIPAddress;
+            hgt.Data["MyIPAddress"] = travel.MyIpAddress;
+
+            m_Database.Store(hgt);
+        }
         #endregion
 
     }
 
     class TravelingAgentInfo
     {
+        public UUID SessionID;
         public UUID UserID;
         public string GridExternalName = string.Empty;
         public string ServiceToken = string.Empty;
         public string ClientIPAddress = string.Empty; // as seen from this user agent service
         public string MyIpAddress = string.Empty; // the user agent service's external IP, as seen from the next gatekeeper
+
+        public TravelingAgentInfo(HGTravelingData t)
+        {
+            if (t.Data != null)
+            {
+                SessionID = new UUID(t.SessionID);
+                UserID = new UUID(t.UserID);
+                GridExternalName = t.Data["GridExternalName"];
+                ServiceToken = t.Data["ServiceToken"];
+                ClientIPAddress = t.Data["ClientIPAddress"];
+                MyIpAddress = t.Data["MyIPAddress"];
+            }
+        }
+
+        public TravelingAgentInfo(TravelingAgentInfo old)
+        {
+            if (old != null)
+            {
+                SessionID = old.SessionID;
+                UserID = old.UserID;
+                GridExternalName = old.GridExternalName;
+                ServiceToken = old.ServiceToken;
+                ClientIPAddress = old.ClientIPAddress;
+                MyIpAddress = old.MyIpAddress;
+            }
+        }
     }
 
 }
diff --git a/OpenSim/Services/HypergridService/UserAgentServiceBase.cs b/OpenSim/Services/HypergridService/UserAgentServiceBase.cs
new file mode 100644
index 0000000..a00e5a6
--- /dev/null
+++ b/OpenSim/Services/HypergridService/UserAgentServiceBase.cs
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Reflection;
+using Nini.Config;
+using OpenSim.Framework;
+using OpenSim.Data;
+using OpenSim.Services.Interfaces;
+using OpenSim.Services.Base;
+
+namespace OpenSim.Services.HypergridService
+{
+    public class UserAgentServiceBase : ServiceBase
+    {
+        protected IHGTravelingData m_Database = null;
+
+        public UserAgentServiceBase(IConfigSource config)
+            : base(config)
+        {
+            string dllName = String.Empty;
+            string connString = String.Empty;
+            string realm = "hg_traveling_data";
+
+            //
+            // Try reading the [DatabaseService] section, if it exists
+            //
+            IConfig dbConfig = config.Configs["DatabaseService"];
+            if (dbConfig != null)
+            {
+                if (dllName == String.Empty)
+                    dllName = dbConfig.GetString("StorageProvider", String.Empty);
+                if (connString == String.Empty)
+                    connString = dbConfig.GetString("ConnectionString", String.Empty);
+            }
+
+            //
+            // [UserAgentService] section overrides [DatabaseService], if it exists
+            //
+            IConfig gridConfig = config.Configs["UserAgentService"];
+            if (gridConfig != null)
+            {
+                dllName = gridConfig.GetString("StorageProvider", dllName);
+                connString = gridConfig.GetString("ConnectionString", connString);
+                realm = gridConfig.GetString("Realm", realm);
+            }
+
+            //
+            // We tried, but this doesn't exist. We can't proceed.
+            //
+            if (dllName.Equals(String.Empty))
+                throw new Exception("No StorageProvider configured");
+
+            m_Database = LoadPlugin<IHGTravelingData>(dllName, new Object[] { connString, realm });
+            if (m_Database == null)
+                throw new Exception("Could not find a storage interface in the given module");
+
+        }
+    }
+}