//移除不活跃的订阅（默认24小时前）
protected void RemoveSubscriber(IEventStorage storage, EventMessage subscriber)
{
//判断队列是否有消息
var queueName = subscriber.ChannelID;
var qkey = this.SubscriberQueuePrefix + queueName;
var qlength = storage.GetLength(qkey);
if (qlength <= 0) //没有任何消息，忽略（实际上此队列在Redis中是不存在的）
{
return;
}
//24小时前
var now = DateTime.Now;
var minTicks = subscriber.Priority > 0 ? now.AddSeconds(-subscriber.Priority).Ticks : now.AddHours(-24).Ticks;
//获取最后一次活跃时间
var qfkey = this.SubscriberRefKeyPrefix + queueName;
var bytes = storage.Get(qfkey);
var remove = true;
if (bytes != null && bytes.Length > 0)
{
var ticks = BitConverter.ToInt64(bytes, 0);
if (ticks > minTicks) //还是活跃的
{
remove = false;
}
}
if (!remove) //此订阅还是活跃的，忽略
{
return;
}
//把订阅信息移除
var sk = this.SubscriberKeyPrefix + queueName;
storage.Delete(sk);
//把队列里的消息引用数-1
var mlist = new List <string>();
do
{
bytes = storage.RightPop(qkey);
if (bytes != null && bytes.Length > 0)
{
var messageId = bytes.ToGuidString();
mlist.Add(this.MessageRefPrefix + messageId);
}
} while(bytes != null);
//把订阅队列移除
storage.Pipeline(s => {
foreach (var msgid in mlist)
{
s.Decrement(msgid);
}
s.Delete(qkey);
});
}