/// <summary>
/// 取分布式锁（基于DB方式）
/// </summary>
/// <param name="moduleFlag">模块标识，模块表名/类名</param>
/// <param name="method_Flag">方法名标识</param>
/// <param name="expirtime">自定义过期时间（秒）</param>
/// <param name="des">锁描述</param>
/// <returns></returns>
public static string DistributeDbLock(string moduleFlag, string method_Flag, double?expirtime = null, string des = null)
{
try
{
if (WebConfigHelper.GetAppSettingValue("EnabledDistributeLock") != "true") //未启用分布式锁
{
return(string.Empty);
}
string hostname = System.Net.Dns.GetHostName(); //当前服务器
string processId = ApplicationObject.GetCurrentProcessId(); //当前进程
string threadId = ApplicationObject.GetCurrentThreadId(); //当前线程
lock (tempObjDistriLock)
{
string errMsg = string.Empty;
int timeout = 30; //30秒超时
DateTime initTime = DateTime.Now;
DatabaseType dbType = DatabaseType.MsSqlServer;
string connStr = ModelConfigHelper.GetModelConnStr(typeof(Other_DistributedLock), out dbType, false);
while ((DateTime.Now - initTime).TotalSeconds <= timeout)
{
double updateTimesamp = Globals.GetTimestamp(DateTime.Now); //当前时间戳
double invalidTimesamp = expirtime.HasValue && expirtime.Value > 0 ? updateTimesamp + expirtime.Value : updateTimesamp + 20; //过期时间戳
Other_DistributedLock methodLock = CommonOperate.GetEntity <Other_DistributedLock>(x => x.ModuleFlag == moduleFlag && x.Method_Flag == method_Flag && x.Invalid_Timesamp > updateTimesamp, null, out errMsg);
//锁存在，继续循环再取
if (methodLock != null)
{
Thread.Sleep(10);
continue;
}
//锁不存在，取得锁成功，插入锁标识
methodLock = new Other_DistributedLock()
{
ModuleFlag = moduleFlag,
Method_Flag = method_Flag,
Update_Timesamp = updateTimesamp,
Invalid_Timesamp = invalidTimesamp,
Maching = hostname,
ProcessId = processId,
ThreadId = threadId,
Des = des
};
TransactionTask tranAction = (conn) =>
{
CommonOperate.DeleteRecordsByExpression <Other_DistributedLock>(x => x.ModuleFlag == moduleFlag && x.Method_Flag == method_Flag, out errMsg, false, connStr, dbType, conn);
if (!string.IsNullOrEmpty(errMsg))
{
throw new Exception(errMsg);
}
CommonOperate.OperateRecord <Other_DistributedLock>(methodLock, ModelRecordOperateType.Add, out errMsg, null, false, false, connStr, dbType, conn);
if (!string.IsNullOrEmpty(errMsg))
{
throw new Exception(errMsg);
}
};
CommonOperate.TransactionHandle(tranAction, out errMsg, connStr, dbType);
//取锁成功
if (string.IsNullOrEmpty(errMsg))
{
return(string.Empty);
}
else
{
WritLockLog(moduleFlag, method_Flag, errMsg);
}
//取锁失败，继续循环取
Thread.Sleep(10);
}
return("获取分布式锁超时"); //取锁失败
}
}
catch
{
return(string.Empty);
}
}