/// We’ll invoke this call-back with message type,name,content when requeue failed message.
/// We’ll invoke this call-back with message type,name,content when retry failed (send or executed) messages equals <see cref="FailedRetryCount"/> times.
/// </summary>
public Action<MessageType, string, string> FailedCallback { get; set; }
public Action<MessageType, string, string> FailedThresholdCallback { get; set; }
/// <summary>
/// The number of message retries, the retry will stop when the threshold is reached.