internal Connection(string stanClusterID, string clientID, StanOptions options)
{
this.clientID = clientID;
connID = Google.Protobuf.ByteString.CopyFrom(System.Text.Encoding.UTF8.GetBytes(pubNUID.Next));
opts = (options != null) ? new StanOptions(options) : new StanOptions();
if (opts.natsConn == null)
{
ncOwned = true;
try
{
nc = new ConnectionFactory().CreateConnection(opts.NatsURL);
nc.Opts.MaxReconnect = Options.ReconnectForever;
// TODO: disable buffering.
}
catch (Exception ex)
{
throw new StanConnectionException(ex);
}
}
else
{
nc = opts.natsConn;
ncOwned = false;
}
// Prepare a subscription on ping responses, even if we are not
// going to need it, so that if that fails, it fails before initiating
// a connection.
pingSubscription = nc.SubscribeAsync(newInbox(), processPingResponse);
// create a heartbeat inbox
string hbInbox = newInbox();
hbSubscription = nc.SubscribeAsync(hbInbox, processHeartBeat);
string discoverSubject = opts.discoverPrefix + "." + stanClusterID;
// The streaming server expects seconds, but can handle millis
// millis are denoted by negative numbers.
int pi;
if (opts.PingInterval < 1000)
{
pi = opts.pingInterval * -1;
}
else
{
pi = opts.pingInterval / 1000;
}
ConnectRequest req = new ConnectRequest
{
ClientID = clientID,
HeartbeatInbox = hbInbox,
ConnID = (Google.Protobuf.ByteString)connID,
Protocol = StanConsts.protocolOne,
PingMaxOut = opts.PingMaxOutstanding,
PingInterval = pi
};
Msg cr;
try
{
cr = nc.Request(discoverSubject,
ProtocolSerializer.marshal(req),
opts.ConnectTimeout);
}
catch (NATSTimeoutException)
{
protoUnsubscribe();
throw new StanConnectRequestTimeoutException(
string.Format("No response from a streaming server with a cluster ID of '{0}'", stanClusterID));
}
ConnectResponse response = new ConnectResponse();
try
{
ProtocolSerializer.unmarshal(cr.Data, response);
}
catch (Exception e)
{
protoUnsubscribe();
throw new StanConnectRequestException(e);
}
if (!string.IsNullOrEmpty(response.Error))
{
protoUnsubscribe();
throw new StanConnectRequestException(response.Error);
}
// capture cluster configuration endpoints to publish and subscribe/unsubscribe
pubPrefix = response.PubPrefix;
subRequests = response.SubRequests;
unsubRequests = response.UnsubRequests;
subCloseRequests = response.SubCloseRequests;
closeRequests = response.CloseRequests;
// setup the Ack subscription
ackSubject = StanConsts.DefaultACKPrefix + "." + newGUID();
ackSubscription = nc.SubscribeAsync(ackSubject, processAck);
// TODO: hardcode or options?
ackSubscription.SetPendingLimits(1024 * 1024, 32 * 1024 * 1024);
pubAckMap = new BlockingDictionary <string, PublishAck>(opts.maxPubAcksInflight);
// TODO - check out sub map and chans
bool unsubPing = true;
// Do this with servers which are at least at protcolOne.
if (response.Protocol >= StanConsts.protocolOne)
{
// Note that in the future server may override client ping
// interval value sent in ConnectRequest, so use the
// value in ConnectResponse to decide if we send PINGs
// and at what interval.
// In tests, the interval could be negative to indicate
// milliseconds.
if (response.PingInterval != 0)
{
unsubPing = false;
// These will be immutable
pingRequests = response.PingRequests;
pingInbox = pingSubscription.Subject;
// negative values returned from the server are ms
if (response.PingInterval < 0)
{
pingInterval = response.PingInterval * -1;
}
else
{
// if positive, the result is in seconds, but
// in the .NET clients we always use millis.
pingInterval = response.PingInterval * 1000;
}
pingMaxOut = response.PingMaxOut;
pingBytes = ProtocolSerializer.createPing(connID);
pingTimer = new Timer(pingServer, null, pingInterval, Timeout.Infinite);
}
}
if (unsubPing)
{
pingSubscription.Unsubscribe();
pingSubscription = null;
}
}
