/// <summary>
/// Try to fall back to next transport. If no more transport to try, it will return false.
/// </summary>
private bool TryFallbackTransport()
{
if (this.State == ConnectionStates.Connecting)
{
if (BufferedMessages != null)
BufferedMessages.Clear();
// stop the current transport
Transport.Stop();
Transport = null;
switch(NextProtocolToTry)
{
#if !BESTHTTP_DISABLE_SERVERSENT_EVENTS
case SupportedProtocols.ServerSentEvents:
Transport = new ServerSentEventsTransport(this);
NextProtocolToTry = SupportedProtocols.HTTP;
break;
#endif
case SupportedProtocols.HTTP:
Transport = new PollingTransport(this);
NextProtocolToTry = SupportedProtocols.Unknown;
break;
case SupportedProtocols.Unknown:
return false;
}
TransportConnectionStartedAt = DateTime.UtcNow;
Transport.Connect();
if (PingRequest != null)
PingRequest.Abort();
return true;
}
return false;
}
/// <summary>
/// Protocol negotiation finished successfully.
/// </summary>
private void OnNegotiationDataReceived(NegotiationData data)
{
#if !BESTHTTP_DISABLE_WEBSOCKET
if (data.TryWebSockets)
{
Transport = new WebSocketTransport(this);
#if !BESTHTTP_DISABLE_SERVERSENT_EVENTS
NextProtocolToTry = SupportedProtocols.ServerSentEvents;
#else
NextProtocolToTry = SupportedProtocols.HTTP;
#endif
}
else
#endif
{
#if !BESTHTTP_DISABLE_SERVERSENT_EVENTS
Transport = new ServerSentEventsTransport(this);
// Long-Poll
NextProtocolToTry = SupportedProtocols.HTTP;
#else
Transport = new PollingTransport(this);
NextProtocolToTry = SupportedProtocols.Unknown;
#endif
}
this.State = ConnectionStates.Connecting;
TransportConnectionStartedAt = DateTime.UtcNow;
Transport.Connect();
}
/// <summary>
/// Protocol negotiation finished successfully.
/// </summary>
private void OnNegotiationDataReceived(NegotiationData data)
{
// Find out what supported protocol the server speak
int protocolIdx = -1;
for (int i = 0; i < ClientProtocols.Length && protocolIdx == -1; ++i)
if (data.ProtocolVersion == ClientProtocols[i])
protocolIdx = i;
// No supported protocol found? Try using the latest one.
if (protocolIdx == -1)
{
protocolIdx = (byte)ProtocolVersions.Protocol_2_2;
HTTPManager.Logger.Warning("SignalR Connection", "Unknown protocol version: " + data.ProtocolVersion);
}
this.Protocol = (ProtocolVersions)protocolIdx;
#if !BESTHTTP_DISABLE_WEBSOCKET
if (data.TryWebSockets)
{
Transport = new WebSocketTransport(this);
#if !BESTHTTP_DISABLE_SERVERSENT_EVENTS
NextProtocolToTry = SupportedProtocols.ServerSentEvents;
#else
NextProtocolToTry = SupportedProtocols.HTTP;
#endif
}
else
#endif
{
#if !BESTHTTP_DISABLE_SERVERSENT_EVENTS
Transport = new ServerSentEventsTransport(this);
// Long-Poll
NextProtocolToTry = SupportedProtocols.HTTP;
#else
Transport = new PollingTransport(this);
NextProtocolToTry = SupportedProtocols.Unknown;
#endif
}
this.State = ConnectionStates.Connecting;
TransportConnectionStartedAt = DateTime.UtcNow;
Transport.Connect();
}