public override SessionStateStoreData GetItemExclusive(HttpContext context, string id, out bool locked, out TimeSpan lockAge, out object lockId, out SessionStateActions actions)
{
LogUtility.LogInfo("GetItemExclusive => Session Id: {0}, Session provider object: {1}.", id, this.GetHashCode());
return(GetItemFromSessionStore(true, context, id, out locked, out lockAge, out lockId, out actions));
}
private SessionStateStoreData GetItemFromSessionStore(bool isWriteLockRequired, HttpContext context, string id, out bool locked, out TimeSpan lockAge, out object lockId, out SessionStateActions actions)
{
try
{
SessionStateStoreData sessionStateStoreData = null;
locked = false;
lockAge = TimeSpan.Zero;
lockId = 0;
actions = SessionStateActions.None;
if (id == null)
{
return(null);
}
GetAccessToStore(id);
ISessionStateItemCollection sessionData = null;
int sessionTimeout;
bool isLockTaken = false;
//Take read or write lock and if locking successful than get data in sessionData and also update session timeout
if (isWriteLockRequired)
{
isLockTaken = cache.TryTakeWriteLockAndGetData(configuration.IsLocking, DateTime.Now, (int)configuration.RequestTimeout.TotalSeconds, out lockId, out sessionData, out sessionTimeout);
sessionId = id; // signal that we have to remove lock in EndRequest
sessionLockId = lockId; // save lockId for EndRequest
}
else
{
isLockTaken = cache.TryCheckWriteLockAndGetData(configuration.IsLocking, out lockId, out sessionData, out sessionTimeout);
}
if (isLockTaken)
{
locked = false;
LogUtility.LogInfo("GetItemFromSessionStore => Session Id: {0}, Session provider object: {1} => Lock taken with lockId: {2}", id, this.GetHashCode(), lockId);
}
else
{
sessionId = null;
sessionLockId = null;
locked = true;
LogUtility.LogInfo("GetItemFromSessionStore => Session Id: {0}, Session provider object: {1} => Can not lock, Someone else has lock and lockId is {2}", id, this.GetHashCode(), lockId);
}
// If locking is not successful then do not return any result just return lockAge, locked=true and lockId.
// ASP.NET tries to acquire lock again in 0.5 sec by calling this method again. Using lockAge it finds if
// lock has been taken more than http request timeout than ASP.NET calls ReleaseItemExclusive and calls this method again to get lock.
if (locked)
{
lockAge = cache.GetLockAge(lockId);
return(null);
}
if (sessionData == null)
{
// If session data do not exists means it might be exipred and removed. So return null so that asp.net can call CreateUninitializedItem and start again.
// But we just locked the record so first release it
ReleaseItemExclusive(context, id, lockId);
return(null);
}
// Restore action flag from session data
if (sessionData["SessionStateActions"] != null)
{
actions = (SessionStateActions)Enum.Parse(typeof(SessionStateActions), sessionData["SessionStateActions"].ToString());
}
//Get data related to this session from sessionDataDictionary and populate session items
sessionData.Dirty = false;
sessionStateStoreData = new SessionStateStoreData(sessionData, new HttpStaticObjectsCollection(), sessionTimeout);
return(sessionStateStoreData);
}
catch (Exception e)
{
LogUtility.LogError("GetItemFromSessionStore => {0}", e.ToString());
locked = false;
lockId = null;
lockAge = TimeSpan.Zero;
actions = 0;
LastException = e;
if (configuration.ThrowOnError)
{
throw;
}
return(null);
}
}
public override SessionStateStoreData CreateNewStoreData(HttpContext context, int timeout)
{
//Creating empty session store data and return it.
LogUtility.LogInfo("CreateNewStoreData => Session provider object: {0}.", this.GetHashCode());
return(new SessionStateStoreData(new ChangeTrackingSessionStateItemCollection(), new HttpStaticObjectsCollection(), timeout));
}
