private void Connection_ConnectionStateChanged(object sender, ConnectionStateChangedEventArgs e)
{
switch (e.NewState)
{
case ConnectionState.Closed:
RemoveConnection(e.Connection);
break;
}
ConnectionStateChanged?.Invoke(this, e);
}
/// <summary>
/// Transition from the current <see cref="ConnectionState"/> to the <paramref name="newState"/>.
/// Returns true if the state was transitioned.
/// If the transition is invalid, <see cref="TransitionInvalidException"/> will be thrown.
/// </summary>
/// <param name="newState">The new state to transition to.</param>
/// <exception cref="InvalidOperationException">If the transition is not valid (determined by <see cref="IsStateTransitionValid(ConnectionState, ConnectionState, bool)"/>)</exception>
protected bool TransitionState(ConnectionState newState)
{
var args = new ConnectionStateChangedEventArgs {
Connection = this,
NewState = newState,
};
bool stateTransitioned = false;
lock (_stateLocker) {
ConnectionState oldState = State;
// The state didn't transition.
if (oldState == newState)
{
return(false);
}
if (!IsStateTransitionValid(oldState, newState))
{
throw new TransitionInvalidException(oldState, newState);
}
// The transition is valid, lets continue.
// Have to set this in the lock statement in case the value changed
args.OldState = oldState;
// Set the new state
_state = newState;
stateTransitioned = oldState != _state;
}
if (stateTransitioned)
{
OnConnectionStateChanged(this, args);
}
return(stateTransitioned);
}
protected virtual void OnConnectionStateChanged(object sender, ConnectionStateChangedEventArgs args)
{
using (var cts = new CancellationTokenSource(TimeSpan.FromSeconds(1))) {
try {
Task.Run(() => {
ConnectionStateChanged?.Invoke(this, args);
}, cts.Token).GetAwaiter().GetResult();
} catch (TaskCanceledException) {
throw new InvalidOperationException("Deadlock detected");
}
}
if (args.NewState == ConnectionState.Closed)
{
try {
_closedCancellation?.Cancel();
} catch (ObjectDisposedException) {
Log.Info($"{this}: {nameof(TransitionState)}: close cancellation disposed");
}
}
}
