/// <summary>
/// Determines the next host.
/// </summary>
/// <returns>A <see cref="FailoverServer"/> object that represents the next available host.</returns>
protected internal override FailoverServer GetNextHost()
{
if (Hosts == null || Hosts?.Count == 0)
{
throw new MySqlException(Resources.Replication_NoAvailableServer);
}
var currentServer = Hosts.Find(h => h.Host == _currentHost.Host && h.Port == _currentHost.Port);
currentServer.IsActive = false;
_hostIndex = Hosts.IndexOf(currentServer);
if (Hosts.Count > 1)
{
_activeHost = _hostIndex == Hosts.Count - 1 ? Hosts[0] : Hosts[_hostIndex + 1];
_activeHost.IsActive = true;
_currentHost = _activeHost;
_hostIndex++;
}
else
{
_activeHost = _initialHost;
}
return(_activeHost);
}
/// <summary>
/// Sets the initial active host.
/// </summary>
protected internal override void SetInitialActiveServer()
{
if (Hosts == null || Hosts.Count == 0)
{
throw new MySqlException(Resources.Replication_NoAvailableServer);
}
_initialHost = Hosts[0];
Hosts[0].IsActive = true;
_activeHost = Hosts[0];
_currentHost = _activeHost;
}
/// <summary>
/// Sets the initial active host.
/// </summary>
protected internal override void SetInitialActiveServer()
{
if (Hosts == null || Hosts.Count == 0)
{
throw new MySqlException(Resources.Replication_NoAvailableServer);
}
var initialIndex = rnd.Next(Hosts.Count);
_initialHost = Hosts[initialIndex];
_initialHost.IsActive = true;
_initialHost.Attempted = true;
_activeHost = _initialHost;
_currentHost = _activeHost;
}
/// <summary>
/// Determines the next host.
/// </summary>
/// <returns>A <see cref="FailoverServer"/> object that represents the next available host.</returns>
protected internal override FailoverServer GetNextHost()
{
if (Hosts == null || Hosts?.Count == 0)
{
throw new MySqlException(Resources.Replication_NoAvailableServer);
}
Hosts.Find(h => h.Host == _currentHost.Host && h.Port == _currentHost.Port).IsActive = false;
var notAttemptedHosts = Hosts.FindAll(h => h.Attempted == false);
if (notAttemptedHosts.Count > 0)
{
_activeHost = notAttemptedHosts[rnd.Next(notAttemptedHosts.Count)];
_activeHost.IsActive = true;
_activeHost.Attempted = true;
_currentHost = _activeHost;
}
else
{
_activeHost = _initialHost;
}
return(_activeHost);
}
/// <summary>
/// Attempts to establish a connection to a host specified from the list.
/// </summary>
/// <param name="originalConnectionString">The original connection string set by the user.</param>
/// <param name="connectionString">An out parameter that stores the updated connection string.</param>
/// <param name="client">A <see cref="Client"/> object in case this is a pooling scenario.</param>
/// <param name="isDefaultPort">A flag indicating if the default port is used in the connection.</param>
/// <returns>An <see cref="InternalSession"/> instance if the connection was succesfully established, a <see cref="MySqlException"/> exception is thrown otherwise.</returns>
internal static InternalSession AttemptConnectionXProtocol(string originalConnectionString, out string connectionString, bool isDefaultPort, Client client = null)
{
if (FailoverGroup == null || originalConnectionString == null)
{
connectionString = null;
return(null);
}
if (client != null)
{
if (client.Hosts == null)
{
client.Hosts = FailoverGroup.Hosts;
client.DemotedHosts = new ConcurrentQueue <FailoverServer>();
}
else
{
FailoverGroup.Hosts = client.Hosts;
}
}
FailoverServer currentHost = FailoverGroup.ActiveHost;
FailoverServer initialHost = currentHost;
MySqlXConnectionStringBuilder Settings = null;
InternalSession internalSession = null;
do
{
// Attempt to connect to each host by retrieving the next host based on the failover method being used.
connectionString = originalConnectionString.Contains("server") ?
originalConnectionString.Replace(originalConnectionString.Split(';').First(p => p.Contains("server")).Split('=')[1], currentHost.Host) :
"server=" + currentHost.Host + ";" + originalConnectionString;
if (currentHost != null && currentHost.Port != -1)
{
connectionString = connectionString.Replace(connectionString.Split(';').First(p => p.Contains("port")).Split('=')[1], currentHost.Port.ToString());
}
Settings = new MySqlXConnectionStringBuilder(connectionString, isDefaultPort);
try { internalSession = InternalSession.GetSession(Settings); }
catch (Exception) { }
if (internalSession != null)
{
break;
}
var tmpHost = currentHost;
currentHost = FailoverGroup.GetNextHost();
if (client != null)
{
tmpHost.DemotedTime = DateTime.Now;
client.Hosts.Remove(tmpHost);
client.DemotedHosts.Enqueue(tmpHost);
if (client.DemotedServersTimer == null)
{
client.DemotedServersTimer = new Timer(new TimerCallback(client.ReleaseDemotedHosts),
null, Client.DEMOTED_TIMEOUT, Timeout.Infinite);
}
}
}while (!currentHost.Equals(initialHost));
// All connection attempts failed.
if (internalSession == null)
{
throw new MySqlException(Resources.UnableToConnectToHost);
}
return(internalSession);
}
/// <summary>
/// Attempts to establish a connection to a host specified from the list.
/// </summary>
/// <param name="connection">MySqlConnection object where the new driver will be assigned</param>
/// <param name="originalConnectionString">The original connection string set by the user.</param>
/// <param name="connectionString">An out parameter that stores the updated connection string.</param>
/// <param name="mySqlPoolManager">A <see cref="MySqlPoolManager"> in case this is a pooling scenario."/></param>
internal static void AttemptConnection(MySqlConnection connection, string originalConnectionString, out string connectionString, bool mySqlPoolManager = false)
{
if (mySqlPoolManager)
{
if (MySqlPoolManager.Hosts == null)
{
MySqlPoolManager.Hosts = FailoverGroup.Hosts;
MySqlPoolManager.DemotedHosts = new ConcurrentQueue <FailoverServer>();
}
else
{
FailoverGroup.Hosts = MySqlPoolManager.Hosts;
}
}
FailoverServer currentHost = FailoverGroup.ActiveHost;
FailoverServer initialHost = currentHost;
Driver driver = null;
do
{
// Attempt to connect to each host by retrieving the next host based on the failover method being used
MySqlConnectionStringBuilder msb;
connectionString = "server=" + currentHost.Host + ";" + originalConnectionString.Substring(originalConnectionString.IndexOf(';') + 1);
if (currentHost != null && currentHost.Port != -1)
{
connectionString += ";port=" + currentHost.Port;
}
msb = new MySqlConnectionStringBuilder(connectionString);
if ((FailoverGroup.Hosts.Count == 1 && !mySqlPoolManager) ||
(mySqlPoolManager && MySqlPoolManager.Hosts.Count == 1 && MySqlPoolManager.DemotedHosts.IsEmpty))
{
return;
}
try
{
driver = Driver.Create(msb);
if (!mySqlPoolManager)
{
connection.driver = driver;
}
break;
}
catch (Exception) { }
var tmpHost = currentHost;
currentHost = FailoverGroup.GetNextHost();
if (mySqlPoolManager)
{
tmpHost.DemotedTime = DateTime.Now;
MySqlPoolManager.Hosts.Remove(tmpHost);
MySqlPoolManager.DemotedHosts.Enqueue(tmpHost);
if (MySqlPoolManager.DemotedServersTimer == null)
{
MySqlPoolManager.DemotedServersTimer = new Timer(new TimerCallback(MySqlPoolManager.ReleaseDemotedHosts),
null, MySqlPoolManager.DEMOTED_TIMEOUT, Timeout.Infinite);
}
}
} while (!currentHost.Equals(initialHost));
if (driver == null)
{
throw new MySqlException(Resources.UnableToConnectToHost);
}
}
