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#if MYSQL_6_9
// Copyright © 2014, 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
// MySQL Connectors. There are special exceptions to the terms and
// conditions of the GPLv2 as it is applied to this software, see the
// FLOSS License Exception
// <http://www.mysql.com/about/legal/licensing/foss-exception.html>.
//
// 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; version 2 of the License.
//
// 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 St, Fifth Floor, Boston, MA 02110-1301 USA
using Externals.MySql.Data.MySqlClient.Properties;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
namespace Externals.MySql.Data.MySqlClient.Replication
{
/// <summary>
/// Base class used to implement load balancing features
/// </summary>
internal abstract class ReplicationServerGroup
{
protected List<ReplicationServer> servers = new List<ReplicationServer>();
/// <param name="name">Group name</param>
/// <param name="retryTime"></param>
public ReplicationServerGroup(string name, int retryTime)
{
Servers = servers;
Name = name;
RetryTime = retryTime;
}
/// <summary>
/// Group name
/// </summary>
public string Name { get; protected set; }
/// <summary>
/// Retry time between connections to failed servers
/// </summary>
public int RetryTime { get; protected set; }
/// <summary>
/// Servers list in the group
/// </summary>
protected IList<ReplicationServer> Servers { get; private set; }
/// <summary>
/// Adds a server into the group
/// </summary>
/// <param name="name">Server name</param>
/// <param name="isMaster">True if the server to add is master, False for slave server</param>
/// <param name="connectionString">Connection string used by this server</param>
/// <returns></returns>
internal protected ReplicationServer AddServer(string name, bool isMaster, string connectionString)
{
ReplicationServer server = new ReplicationServer(name, isMaster, connectionString);
servers.Add(server);
return server;
}
/// <summary>
/// Removes a server from group
/// </summary>
/// <param name="name">Server name</param>
internal protected void RemoveServer(string name)
{
ReplicationServer serverToRemove = GetServer(name);
if (serverToRemove == null)
throw new MySqlException(String.Format(Resources.ReplicationServerNotFound, name));
servers.Remove(serverToRemove);
}
/// <summary>
/// Gets a server by name
/// </summary>
/// <param name="name">Server name</param>
/// <returns>Replication server</returns>
internal protected ReplicationServer GetServer(string name)
{
foreach (var server in servers)
if (String.Compare(name, server.Name, StringComparison.OrdinalIgnoreCase) == 0) return server;
return null;
}
/// <summary>
/// Must be implemented. Defines the next server for a custom load balancing implementation.
/// </summary>
/// <param name="isMaster">Defines if the server to return is a master or any</param>
/// <returns>Next server based on the load balancing implementation.
/// Null if no available server is found.
/// </returns>
internal protected abstract ReplicationServer GetServer(bool isMaster);
internal protected virtual ReplicationServer GetServer(bool isMaster, MySqlConnectionStringBuilder settings)
{
return GetServer(isMaster);
}
/// <summary>
/// Handles a failed connection to a server.
/// This method can be overrided to implement a custom failover handling
/// </summary>
/// <param name="server">The failed server</param>
internal protected virtual void HandleFailover(ReplicationServer server)
{
BackgroundWorker worker = new BackgroundWorker();
worker.DoWork += delegate(object sender, DoWorkEventArgs e)
{
bool isRunning = false;
ReplicationServer server1 = e.Argument as ReplicationServer;
System.Timers.Timer timer = new System.Timers.Timer(RetryTime * 1000.0);
System.Timers.ElapsedEventHandler elapsedEvent = delegate(object sender1, System.Timers.ElapsedEventArgs e1)
{
if (isRunning) return;
try
{
isRunning = true;
using (MySqlConnection connectionFailed = new MySqlConnection(server.ConnectionString))
{
connectionFailed.Open();
server1.IsAvailable = true;
timer.Stop();
}
}
catch
{
MySqlTrace.LogWarning(0,
string.Format(Properties.Resources.Replication_ConnectionAttemptFailed, server1.Name));
}
finally
{
isRunning = false;
}
};
timer.Elapsed += elapsedEvent;
timer.Start();
elapsedEvent(sender, null);
};
worker.RunWorkerAsync(server);
}
/// <summary>
/// Handles a failed connection to a server.
/// </summary>
/// <param name="server">The failed server</param>
/// <param name="exception">Exception that caused the failover</param>
internal protected virtual void HandleFailover(ReplicationServer server, Exception exception)
{
HandleFailover(server);
}
}
}
#endif