protected void ResetServers(IList <Server> servers)
{
var rightServers = new List <Server>();
foreach (var server in from server in servers where server != null select server)
{
server.Online();
rightServers.Add(server);
_logger.LogDebug($"LoadBalancer [{_name}]: addServer [{server}]");
}
try
{
_allServerLock.EnterReadLock();
var allServer = AllServer.ToList();
_allServerLock.ExitReadLock();
var newServers = (from server in rightServers where !allServer.Contains(server) select server).ToArray();
_allServerLock.EnterWriteLock();
AllServer = new ConcurrentBag <Server>(newServers.Union(allServer));
_allServerLock.ExitWriteLock();
if (newServers.Length != 0)
{
Interlocked.Exchange(ref _pingInProgress, 0);
RunPing();
ServersChanged?.Invoke(this, newServers);
}
}
finally
{
if (_allServerLock.IsReadLockHeld)
{
_allServerLock.ExitReadLock();
}
if (_allServerLock.IsWriteLockHeld)
{
_allServerLock.ExitWriteLock();
}
}
}
public void MarkServerDown(Server server)
{
if (server == null || !server.IsAlive || !server.ReadyToServe)
{
return;
}
_logger.LogDebug($"LoadBalancer [{_name}]: markServerDown called on [{server}]");
try
{
_allServerLock.EnterWriteLock();
server.Zombify();
server.Offline();
_allServerLock.ExitReadLock();
ServersChanged?.Invoke(this, new Server[] { server });
}
finally
{
if (_allServerLock.IsReadLockHeld)
{
_allServerLock.ExitReadLock();
}
}
}
public void RemoveServer(Server server)
{
if (server.ID == null)
{
throw new NullIdException("Server ID is null.");
}
removeServer.Parameters["@ID"].Value = server.ID;
try
{
connection.Open();
if (removeServer.ExecuteNonQuery() == 0)
{
throw new ZeroRowsExecutedException();
}
}
finally
{
Close();
removeServer.Parameters["@ID"].Value = DBNull.Value;
}
ServersChanged?.Invoke();
}
private void ServerCollection_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
ServersChanged?.Invoke(this, new EventArgs());
}
public static void RaiseServersChangedEvent(object sender)
{
ServersChanged?.Invoke(sender, null);
}
private void RunPing()
{
try
{
if (_ping == null)
{
return;
}
if (_handing)
{
return;
}
_handing = true;
_allServerLock.EnterReadLock();
var servers = AllServer.Where(x => x.ReadyToServe).ToArray();
_allServerLock.ExitReadLock();
var result = _pingStrategy.PingServers(_ping, servers);
if (Interlocked.CompareExchange(ref _pingInProgress, 1, 0) == 1)
{
return;
}
_logger.LogDebug("开始执行ping操作");
var changedServers = new List <Server>();
var upServers = new List <Server>();
try
{
foreach (var item in result)
{
var server = item.Server;
var isAlive = item.IsAlive;
if (server.IsAlive != isAlive)
{
changedServers.Add(item.Server);
_logger.LogDebug($"LoadBalancer [{_name}]: Server [{server}] status changed to {(isAlive ? "ALIVE" : "DEAD")}");
}
if (isAlive)
{
server.Unzombify();
upServers.Add(server);
}
}
_upServerLock.EnterWriteLock();
UpServer = new ConcurrentBag <Server>(upServers);
_upServerLock.ExitWriteLock();
ServersChanged?.Invoke(this, changedServers.ToArray());
}
finally
{
if (_upServerLock.IsWriteLockHeld)
{
_upServerLock.ExitWriteLock();
}
Interlocked.Exchange(ref _pingInProgress, 0);
}
}
finally
{
if (_allServerLock.IsReadLockHeld)
{
_allServerLock.ExitReadLock();
}
_handing = false;
}
}
