MySql Connector/Net fabric server selection broken when master is faulty (Oracle Bug #21203824).

Added fabric server status (only primary and secondary) when selecting a server (excludes the faulty and spare servers).
Added new constructor for MySqlFabricException that accepts an exception as parameter.
Reorganized Fabric plugin Enums.
Added new validation and resource error message when the specified group is not found in fabric groups list.

Author: Roberto E. Garcia

CHANGES

@@ -1,6 +1,8 @@
 6.9.7
 - Changed default SSL mode to Preferred in connection string. Now the server connections will be using SSL if server allows it by default but it's possible to override this configuration.
 - Changed handshake process to use bytes instead of encoded strings.
+- Fix for Fabric connections (Oracle Bug #20983968).
+- Fix for Fabric plugin: fabric server selection is broken when master is faulty (Oracle Bug #21203824).
 
 
 6.9.6

Source/Plugins/MySql.Fabric/Enums.cs

@@ -1,4 +1,4 @@
-// Copyright © 2014, Oracle and/or its affiliates. All rights reserved.
+// Copyright © 2014, 2015 Oracle and/or its affiliates. All rights reserved.
 //
 // MySQL Connector/NET is licensed under the terms of the GPLv2
 // <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most 
@@ -27,18 +27,18 @@ namespace MySql.Fabric
   [Flags]
   public enum FabricServerModeEnum
   {
-    Offline = 0x1,
-    Read_only = 0x2,
-    Write_only = 0x4,
-    Read_Write = 0x8
+    Offline = 0,
+    Read_only = 1,
+    Write_only = 2,
+    Read_Write = 4
   }
 
   internal enum FabricServerStatusEnum
   {
     Faulty = 0,
-    Spare,
-    Secondary,
-    Primary
+    Spare = 1,
+    Secondary = 2,
+    Primary = 3
   }
 
   public enum FabricScopeEnum

Source/Plugins/MySql.Fabric/FabricServerGroup.cs

@@ -1,4 +1,4 @@
-// Copyright © 2014, Oracle and/or its affiliates. All rights reserved.
+// Copyright © 2014, 2015 Oracle and/or its affiliates. All rights reserved.
 //
 // MySQL Connector/NET is licensed under the terms of the GPLv2
 // <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most 
@@ -54,6 +54,7 @@ internal class FabricServerGroup : ReplicationServerGroup
     // always in the format "schema.table"
     internal string tableProperty;
     internal object keyProperty;
+    ReplicationServer lastServer = null;
 
 
     public FabricServerGroup(string name, int retryTime)
@@ -111,14 +112,24 @@ internal protected override ReplicationServer GetServer(bool isMaster, MySqlConn
 
         fabricConnection = new MySqlConnection(servers[0].ConnectionString);
       }
+      bool hasChanged = false;
+
+      if (groupIdProperty != settings.FabricGroup) hasChanged = true;
       groupIdProperty = settings.FabricGroup;
+      if (modeProperty != (FabricServerModeEnum?)settings.FabricServerMode) hasChanged = true;
       modeProperty = (FabricServerModeEnum?)settings.FabricServerMode;
+      if (tableProperty != settings.ShardingTable) hasChanged = true;
       tableProperty = settings.ShardingTable;
+      if (keyProperty != settings.ShardingKey) hasChanged = true;
       keyProperty = settings.ShardingKey;
 
-      GetServerList();
+      if (hasChanged)
+      {
+        GetServerList();
+        lastServer = GetServer(isMaster);
+      }
 
-      return GetServer(isMaster);
+      return lastServer;
     }
 
     private ReplicationServer GetServerByShard(FabricServerModeEnum mode)
@@ -142,7 +153,12 @@ private ReplicationServer GetServerByShard(FabricServerModeEnum mode)
 
     private ReplicationServer GetServerByGroup(FabricServerModeEnum mode, string groupId)
     {
-      var serversInGroup = FabricGroups[groupId].Servers.Where(i => (i.Mode & mode) != 0).ToList();
+      if (!FabricGroups.ContainsKey(groupId))
+        throw new MySqlFabricException(string.Format(Properties.Resources.errorGroupNotFound, groupId));
+
+      var serversInGroup = FabricGroups[groupId].Servers.Where(i => (i.Mode & mode) != 0 
+        && (i.Status == FabricServerStatusEnum.Primary 
+        || i.Status == FabricServerStatusEnum.Secondary)).ToList();
 
       if (serversInGroup.Count == 0) return null;
 
@@ -190,7 +206,14 @@ private int ShardKeyCompare(object o1, object o2, FabricShardIndexType shardType
 
     internal protected override void HandleFailover(ReplicationServer server, Exception exception)
     {
-      ExecuteCommand("threat report_error", server.Name);
+      try
+      {
+        ExecuteCommand("threat report_error", server.Name);
+      }
+      catch (Exception ex)
+      {
+        MySqlTrace.LogError(-1, ex.ToString());
+      }
       GetServerList();
       throw exception;
     }
@@ -228,10 +251,8 @@ protected DataTable ExecuteCommand(string command, params string[] parameters)
     protected void GetServerList()
     {
       if (lastUpdate.AddSeconds(ttl) > DateTime.Now) return;
-      //lock (FabricServers)
       lock (_lockObject)
       {
-        if (FabricGroups.Count != 0) return;
         try
         {
           GetGroups();
@@ -241,7 +262,7 @@ protected void GetServerList()
         catch (Exception ex)
         {
           MySqlTrace.LogError(-1, ex.ToString());
-          throw new MySqlFabricException(Properties.Resources.errorConnectFabricServer);
+          throw new MySqlFabricException(Properties.Resources.errorConnectFabricServer, ex);
         }
       }
     }

Source/Plugins/MySql.Fabric/MySqlFabricException.cs

@@ -1,4 +1,4 @@
-// Copyright © 2014, Oracle and/or its affiliates. All rights reserved.
+// Copyright © 2014, 2015 Oracle and/or its affiliates. All rights reserved.
 //
 // MySQL Connector/NET is licensed under the terms of the GPLv2
 // <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most 
@@ -30,5 +30,10 @@ public MySqlFabricException(string message)
       : base(message)
     {
     }
+
+    public MySqlFabricException(string message, Exception innerException)
+      : base(message, innerException)
+    {
+    }
   }
 }

Source/Plugins/MySql.Fabric/Properties/Resources.Designer.cs

@@ -126,6 +126,9 @@
   <data name="errorGroupAndTable" xml:space="preserve">
     <value>You have set a group name and a sharding table at the same time. Please set only one.</value>
   </data>
+  <data name="errorGroupNotFound" xml:space="preserve">
+    <value>Group '{0}' not found.</value>
+  </data>
   <data name="errorNoFabricSettings" xml:space="preserve">
     <value>No Fabric settins found.</value>
   </data>