private void SetDescription(ServerDescription newDescription, bool forceClearConnectionPool)
{
// Current assumption is SetDescription is always synchronized under _monitor.Lock.
// This synchronization technically can be violated by calling server.Invalidate not under _monitor.Lock.
// Therefore _currentDescription and ConnectionPool state can get out of sync.
var serverDescriptionChangedEvent = new ServerDescriptionChangedEventArgs(_currentDescription, newDescription);
_currentDescription = newDescription;
if (newDescription.HeartbeatException != null || forceClearConnectionPool)
{
// propagate event to upper levels
TriggerServerDescriptionChanged(this, serverDescriptionChangedEvent);
// pool must be cleared on after cluster update
ConnectionPool.Clear();
}
else
{
if (newDescription.IsDataBearing ||
(newDescription.Type != ServerType.Unknown && IsDirectConnection()))
{
// The spec requires to check (server.type != Unknown and newTopologyDescription.type == Single)
// in C# driver servers in single topology will be only selectable if direct connection was requested
// therefore it is sufficient to check whether the connection mode is directConnection.
ConnectionPool.SetReady();
}
// propagate event to upper levels
TriggerServerDescriptionChanged(this, serverDescriptionChangedEvent);
}
}
protected override void HandleBeforeHandshakeCompletesException(Exception ex)
{
if (ex is MongoAuthenticationException)
{
ConnectionPool.Clear();
return;
}
if (ex is MongoConnectionException mongoConnectionException)
{
lock (_monitor.Lock)
{
if (mongoConnectionException.Generation != null &&
mongoConnectionException.Generation != ConnectionPool.Generation)
{
return; // stale generation number
}
if (mongoConnectionException.IsNetworkException &&
!mongoConnectionException.ContainsTimeoutException)
{
_monitor.CancelCurrentCheck();
}
if (mongoConnectionException.IsNetworkException || mongoConnectionException.ContainsTimeoutException)
{
Invalidate($"ChannelException during handshake: {ex}.", clearConnectionPool: true, topologyVersion: null);
}
}
}
}
private void OnDescriptionChanged(object sender, ServerDescriptionChangedEventArgs e)
{
if (e.NewServerDescription.HeartbeatException != null)
{
ConnectionPool.Clear();
}
// propagate event to upper levels
TriggerServerDescriptionChanged(this, e);
}
protected override void HandleBeforeHandshakeCompletesException(Exception ex)
{
// drivers MUST NOT perform SDAM error handling for any errors that occur before the MongoDB Handshake
if (ex is MongoAuthenticationException mongoAuthenticationException &&
mongoAuthenticationException.ServiceId.HasValue) // this value will be always filled for MongoAuthenticationException, adding this condition just in case
{
// when requiring the connection pool to be cleared, MUST only clear connections for the serviceId.
ConnectionPool.Clear(mongoAuthenticationException.ServiceId.Value);
}
}
// public methods
public override void Invalidate(string reasonInvalidated, bool clearConnectionPool, TopologyVersion topologyVersion)
{
if (clearConnectionPool)
{
ConnectionPool.Clear();
}
var newDescription = _baseDescription.With(
$"InvalidatedBecause:{reasonInvalidated}",
lastUpdateTimestamp: DateTime.UtcNow,
topologyVersion: topologyVersion);
SetDescription(newDescription);
// TODO: make the heartbeat request conditional so we adhere to this part of the spec
// > Network error when reading or writing: ... Clients MUST NOT request an immediate check of the server;
// > since application sockets are used frequently, a network error likely means the server has just become
// > unavailable, so an immediate refresh is likely to get a network error, too.
RequestHeartbeat();
}
protected override void HandleAfterHandshakeCompletesException(IConnection connection, Exception ex)
{
lock (_connectionPoolLock)
{
if (ex is MongoConnectionException mongoConnectionException &&
mongoConnectionException.Generation.HasValue &&
mongoConnectionException.Generation.Value != ConnectionPool.GetGeneration(connection.Description?.ServiceId))
{
return; // stale generation number
}
if (ShouldClearConnectionPoolForChannelException(ex, connection.Description.ServerVersion) &&
connection.Description.ServiceId.HasValue) // this value will be always filled in this place, adding this here just in case
{
// when requiring the connection pool to be cleared, MUST only clear connections for the serviceId.
ConnectionPool.Clear(connection.Description.ServiceId.Value);
}
}
}