private bool CanRegister(NodeConnection connection)
{
if (cancellationToken.IsCancellationRequested)
{
return false;
}
if (connection.Direction == NodeConnectionDirection.Incoming)
{
if (incomingConnectionsCount >= maxIncomingConnectionsCount)
{
return false;
}
//todo: should IsConnected be checked for incoming connections?
}
else if (connection.Direction == NodeConnectionDirection.Outgoing)
{
if (outgoingConnectionsCount >= maxOutgoingConnectionsCount)
{
return false;
}
if (IsConnected(connection.Endpoint.PeerInfo.IpEndpoint.Address))
{
return false;
}
}
else
{
throw new InvalidOperationException($"Unexpected connection direction: {connection.Direction}.");
}
return true;
}
private void Remove(NodeConnection connection)
{
lock (lockObject)
{
if (!connections.Remove(connection))
{
return;
}
if (connection.Direction == NodeConnectionDirection.Incoming)
{
incomingConnectionsCount--;
}
else if (connection.Direction == NodeConnectionDirection.Outgoing)
{
outgoingConnectionsCount--;
}
else
{
throw new InvalidOperationException($"Unexpected connection direction: {connection.Direction}.");
}
}
Changed?.Invoke();
}
/// <summary>
/// Adds a connection to the collection.
/// <para/>
/// Can reject the connection if the cancellation token was cancelled or the maximum number of connections is reached.
/// </summary>
/// <param name="direction">The direction of the connection.</param>
/// <param name="endpoint">The connection to a Bitcoin node.</param>
/// <returns>true if the connection was accepted; otherwise false.</returns>
public bool Add(NodeConnectionDirection direction, BitcoinEndpoint endpoint)
{
NodeConnection connection = new NodeConnection(direction, endpoint);
lock (lockObject)
{
if (!CanRegister(connection))
{
return false;
}
if (direction == NodeConnectionDirection.Incoming)
{
incomingConnectionsCount++;
}
else if (direction == NodeConnectionDirection.Outgoing)
{
outgoingConnectionsCount++;
}
else
{
throw new InvalidOperationException($"Unexpected connection direction: {direction}.");
}
connections.Add(connection);
}
endpoint.CallWhenDisconnected(() => Remove(connection));
Changed?.Invoke();
return true;
}