/// <summary>
/// The amount of time a Topic should stay in memory after its last subscriber is removed.
/// </summary>
/// <param name="options"></param>
/// <returns></returns>
public static TimeSpan TopicTtl(this TransportOptions options)
{
// If the deep-alive is disabled, don't take it into account when calculating the topic TTL.
var keepAliveTimeout = options.KeepAliveTimeout() ?? TimeSpan.Zero;
// Keep topics alive for twice as long as we let connections to reconnect. (The DisconnectTimeout)
// Also add twice the keep-alive timeout since clients might take a while to notice they are disconnected.
// This should be a very conservative estimate for how long we must wait before considering a topic dead.
return(TimeSpan.FromTicks((options.DisconnectTimeout.Ticks + keepAliveTimeout.Ticks) * 2));
}
/// <summary>
/// The amount of time the client should wait without seeing a keep alive before trying to reconnect.
/// </summary>
public static TimeSpan?KeepAliveTimeout(this TransportOptions options)
{
if (options.KeepAlive != null)
{
return(TimeSpan.FromTicks(options.KeepAlive.Value.Ticks * MissedTimeoutsBeforeClientReconnect));
}
else
{
return(null);
}
}
/// <summary>
/// The interval between successively checking connection states.
/// </summary>
public static TimeSpan HeartbeatInterval(this TransportOptions options)
{
if (options.KeepAlive != null)
{
return(TimeSpan.FromTicks(options.KeepAlive.Value.Ticks / HeartBeatsPerKeepAlive));
}
else
{
// If KeepAlives are disabled, have the heartbeat run at the same rate it would if the KeepAlive was
// kept at the default value.
return(TimeSpan.FromTicks(options.DisconnectTimeout.Ticks / HeartBeatsPerDisconnectTimeout));
}
}
/// <summary>
/// Initializes and instance of the <see cref="TransportHeartbeat"/> class.
/// </summary>
/// <param name="serviceProvider">The <see cref="IDependencyResolver"/>.</param>
public TransportHeartbeat(IOptions<SignalROptions> optionsAccessor,
IPerformanceCounterManager counters,
ILoggerFactory loggerFactory)
{
_transportOptions = optionsAccessor.Value.Transports;
_counters = counters;
_logger = loggerFactory.CreateLogger<TransportHeartbeat>();
// REVIEW: When to dispose the timer?
_timer = new Timer(Beat,
null,
_transportOptions.HeartbeatInterval(),
_transportOptions.HeartbeatInterval());
}
public SignalROptions()
{
Hubs = new HubOptions();
MessageBus = new MessageBusOptions();
Transports = new TransportOptions();
}
