public override void CreateUninitializedItem(HttpContext context, string id, int timeout)
{
Debug.Assert(context != null, "Http context is null");
SecUtility.CheckParameter(ref id, true, true, false, ProvidersConfiguration.MaxStringPropertySizeInChars, "id");
if (timeout < 0)
{
throw new ArgumentException("Parameter timeout must be a non-negative integer!");
}
try
{
TableServiceContext svc = this.CreateDataServiceContext();
var session = new SessionRow(id, this.applicationName)
{
Lock = 0,
Initialized = false,
Id = id,
Timeout = timeout,
ExpiresUtc = DateTime.UtcNow.AddMinutes(timeout)
};
// no lock
svc.AddObject(this.tableName, session);
svc.SaveChangesWithRetries();
}
catch (InvalidOperationException e)
{
throw new ProviderException("Error accessing the data store.", e);
}
}
private static void ReleaseItemExclusive(TableServiceContext svc, SessionRow session, object lockId)
{
if ((int)lockId != session.Lock)
{
// obviously that can happen, but let's see when at least in Debug mode
Debug.Assert(false, "Error");
return;
}
session.ExpiresUtc = DateTime.UtcNow.AddMinutes(session.Timeout);
session.Locked = false;
svc.UpdateObject(session);
svc.SaveChangesWithRetries();
}
public override void SetAndReleaseItemExclusive(
HttpContext context, string id, SessionStateStoreData item, object lockId, bool newItem)
{
Debug.Assert(context != null, "Http context is null");
SecUtility.CheckParameter(ref id, true, true, false, ProvidersConfiguration.MaxStringPropertySizeInChars, "id");
this.providerRetryPolicy(() =>
{
TableServiceContext svc = CreateDataServiceContext();
SessionRow session;
if (!newItem)
{
session = GetSession(id, svc);
if (session == null || session.Lock != (int)lockId)
{
Debug.Assert(false, "Error");
return;
}
}
else
{
session = new SessionRow(id, this.applicationName);
session.Lock = 1;
session.LockDateUtc = DateTime.UtcNow;
}
session.Initialized = true;
Debug.Assert(session.Timeout >= 0, "Session timeout is < 0");
session.Timeout = item.Timeout;
session.ExpiresUtc = DateTime.UtcNow.AddMinutes(session.Timeout);
session.Locked = false;
// yes, we always create a new blob here
session.BlobName = GetBlobNamePrefix(id) + Guid.NewGuid().ToString("N");
// Serialize the session and write the blob
byte[] items, statics;
SerializeSession(item, out items, out statics);
string serializedItems = Convert.ToBase64String(items);
string serializedStatics = Convert.ToBase64String(statics);
MemoryStream output = new MemoryStream();
StreamWriter writer = new StreamWriter(output);
try
{
writer.WriteLine(serializedItems);
writer.WriteLine(serializedStatics);
writer.Flush();
// for us, it shouldn't matter whether newItem is set to true or false
// because we always create the entire blob and cannot append to an
// existing one
this.blobProvider.UploadStream(session.BlobName, output);
writer.Close();
output.Close();
}
catch (Exception e)
{
if (!newItem)
{
ReleaseItemExclusive(svc, session, lockId);
}
throw new ProviderException("Error accessing the data store.", e);
}
finally
{
if (writer != null)
{
writer.Close();
}
if (output != null)
{
output.Close();
}
}
if (newItem)
{
svc.AddObject(this.tableName, session);
svc.SaveChangesWithRetries();
}
else
{
// Unlock the session and save changes
ReleaseItemExclusive(svc, session, lockId);
}
});
}