private async Task GrabRedPacket(string redPacketId, RedPacketRecord redPacketRecord)
{
bool?tryAgain;
do
{
var token = Environment.MachineName;
if (_client.Database.LockTake(redPacketId, token, TimeSpan.FromSeconds(10)))
{
try
{
var redPacket = await _client.HashGetAsync <RedPacket>(nameof(RedPacket), redPacketId);
redPacket.RemainingCount--;
if (redPacket.RemainingCount >= 0)
{
redPacketRecord.Id = await _client.StringIncrementAsync($"{nameof(RedPacketRecord)}_ID");
if (redPacket.RemainingCount == 0)
{
//最后一人
redPacketRecord.Amount = redPacket.RemainingAmount;
redPacket.RemainingAmount = 0;
}
else
{
//抢到红包最多为剩余人均的2倍
var maxAmount = (redPacket.RemainingAmount / (redPacket.RemainingCount + 1) * 2 - 1);
redPacketRecord.Amount = new Random().Next(1, maxAmount);
redPacket.RemainingAmount -= redPacketRecord.Amount;
}
await _client.HashSetAsync(nameof(RedPacket), redPacketId, redPacket);
await _client.HashSetAsync(nameof(RedPacketRecord), redPacketRecord.Id.ToString(), redPacketRecord);
tryAgain = false;
_logger.LogError($"成功抢红包{redPacketRecord.Amount / (100 * 1.0)}元:{redPacketRecord.CreateUser}");
}
else
{
//抢完了
tryAgain = null;
_logger.LogError("抢完了");
}
}
finally
{
_client.Database.LockRelease(redPacketId, token);
}
}
else
{
//锁住了,正在抢购中,等待所释放后再次抢
tryAgain = true;
await Task.Delay(50);
}
} while (tryAgain.HasValue && tryAgain.Value);
}
public async Task <IActionResult> CreateRedPacketRecord([FromBody] RedPacketRecordViewModel viewModel)
{
var redPacketRecord = new RedPacketRecord
{
CreateTime = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"),
CreateUser = viewModel.CreateUser,
RedPacketId = viewModel.RedPacketId
};
var redPacketId = viewModel.RedPacketId.ToString();
await GrabRedPacket(redPacketId, redPacketRecord);
return(Ok(redPacketRecord));
}
