/// <summary>
/// Assigns a new server driver to the connection object
/// </summary>
/// <param name="groupName">Group name</param>
/// <param name="master">True if the server connection to assign must be a master</param>
/// <param name="connection">MyCatConnection object where the new driver will be assigned</param>
internal static void GetNewConnection(string groupName, bool master, MyCatConnection connection)
{
do
{
lock (thisLock)
{
if (!IsReplicationGroup(groupName))
{
return;
}
ReplicationServerGroup group = GetGroup(groupName);
ReplicationServer server = group.GetServer(master, connection.Settings);
if (server == null)
{
throw new MyCatException(Properties.Resources.Replication_NoAvailableServer);
}
try
{
bool isNewServer = false;
if (connection.driver == null || !connection.driver.IsOpen)
{
isNewServer = true;
}
else
{
MyCatConnectionStringBuilder msb = new MyCatConnectionStringBuilder(server.ConnectionString);
if (!msb.Equals(connection.driver.Settings))
{
isNewServer = true;
}
}
if (isNewServer)
{
Driver driver = Driver.Create(new MyCatConnectionStringBuilder(server.ConnectionString));
connection.driver = driver;
}
return;
}
catch (MyCatException ex)
{
connection.driver = null;
server.IsAvailable = false;
MyCatTrace.LogError(ex.Number, ex.ToString());
if (ex.Number == 1042)
{
// retry to open a failed connection and update its status
group.HandleFailover(server, ex);
}
else
{
throw;
}
}
}
} while (true);
}
/// <summary>
/// Adds a Server Group to the list
/// </summary>
/// <param name="name">Group name</param>
/// <param name="groupType">ServerGroup type reference</param>
/// <param name="retryTime">Time between reconnections for failed servers</param>
/// <returns>Server Group added</returns>
internal static ReplicationServerGroup AddGroup(string name, string groupType, int retryTime)
{
if (string.IsNullOrEmpty(groupType))
{
groupType = "Pomelo.Data.MyCat.Replication.ReplicationRoundRobinServerGroup";
}
Type t = Type.GetType(groupType);
ReplicationServerGroup g = (ReplicationServerGroup)Activator.CreateInstance(t, name, retryTime) as ReplicationServerGroup;
groups.Add(g);
return(g);
}
/// <summary>
/// Gets a Server Group by name
/// </summary>
/// <param name="groupName">Group name</param>
/// <returns>Server Group if found, otherwise throws an MyCatException</returns>
internal static ReplicationServerGroup GetGroup(string groupName)
{
ReplicationServerGroup group = null;
foreach (ReplicationServerGroup g in groups)
{
if (String.Compare(g.Name, groupName, StringComparison.OrdinalIgnoreCase) != 0)
{
continue;
}
group = g;
break;
}
if (group == null)
{
throw new MyCatException(String.Format(Resources.ReplicationGroupNotFound, groupName));
}
return(group);
}
//private static Dictionary<string, ReplicationServerSelector> selectors = new Dictionary<string, ReplicationServerSelector>();
static ReplicationManager()
{
Groups = groups;
// load up our selectors
if (MyCatConfiguration.Settings == null)
{
return;
}
foreach (var group in MyCatConfiguration.Settings.Replication.ServerGroups)
{
ReplicationServerGroup g = AddGroup(group.Name, group.GroupType, group.RetryTime);
foreach (var server in group.Servers)
{
g.AddServer(server.Name, server.IsMaster, server.ConnectionString);
}
}
}
/// <summary>
/// Gets the next server from a replication group
/// </summary>
/// <param name="groupName">Group name</param>
/// <param name="isMaster">True if the server to return must be a master</param>
/// <returns>Replication Server defined by the Load Balancing plugin</returns>
internal static ReplicationServer GetServer(string groupName, bool isMaster)
{
ReplicationServerGroup group = GetGroup(groupName);
return(group.GetServer(isMaster));
}