private void GetChannelAndSubscription(string localIp,
int streamId,
out string clientChannel,
out Subscription subscription)
{
// Finding port for the first time is slow and in tests with
// parallel connections many clients have different ports.
// Simple lock is needed.
lock (_connectionsLock)
{
while (true)
{
if (_clientPort == 0)
{
var clientPort = 0;
while (true)
{
try
{
clientPort = UdpUtils.GetRandomUnusedPort();
clientChannel = Utils.RemoteChannel(localIp, clientPort);
subscription = _client.AddSubscription(clientChannel, streamId);
break;
}
catch (RegistrationException ex)
{
// if port was already reused by someone
_log.Warn($"Could not subscribe on new port {clientPort}", ex);
}
}
_clientPort = clientPort;
return;
}
try
{
clientChannel = Utils.RemoteChannel(localIp, _clientPort);
subscription = _client.AddSubscription(clientChannel, streamId);
return;
}
catch (RegistrationException ex)
{
_log.Warn($"Could not subscribe on existing port {_clientPort}", ex);
_clientPort = 0;
}
}
}
}
public int Connect(string serverHost,
int serverPort,
Action onConnectedDelegate,
Action onDisconnectedDelegate,
AeronClientMessageReceivedHandler onMessageReceived,
int connectionResponseTimeoutMs)
{
if (serverHost == null)
{
throw new ArgumentNullException(nameof(serverHost));
}
if (_isTerminatedUnexpectedly)
{
return(-1);
}
string serverHostIp;
if (serverHost.Equals("localhost", StringComparison.OrdinalIgnoreCase) || serverHost.Equals("127.0.0.1", StringComparison.OrdinalIgnoreCase))
{
// TODO IPC channel for local communication
serverHostIp = "127.0.0.1";
}
else
{
var ipv4 =
Dns.GetHostEntry(serverHost).AddressList
.FirstOrDefault(x => x.AddressFamily == AddressFamily.InterNetwork)
?? throw new ArgumentException($"Cannot resolve serverHost ip for {serverHost}");
serverHostIp = ipv4.ToString();
}
var serverChannel = Utils.RemoteChannel(serverHostIp, serverPort);
var publication = _client.AddExclusivePublication(serverChannel, AeronServer.ServerStreamId);
var localIp = UdpUtils.GetLocalIPAddress(serverHostIp, serverPort);
var streamId = MachineCounters.Instance.GetNewClientStreamId();
GetChannelAndSubscription(localIp, streamId, out var clientChannel, out var subscription);
var session = new AeronClientSession(this,
serverChannel,
publication,
subscription,
onConnectedDelegate,
onDisconnectedDelegate,
onMessageReceived);
var connectionId = AddSession(session);
_log.Info($"Connecting: {session}");
var handshakeRequest = new AeronHandshakeRequest
{
Channel = clientChannel,
StreamId = streamId
};
if (!session.SendHandshake(handshakeRequest, connectionResponseTimeoutMs))
{
RemoveSession(session);
session.Dispose();
return(-1);
}
return(connectionId);
}