private void ReleaseLockInternal(LockArgs lockArgs, LockContext context, CloudBlockBlob blob, string leaseId)
{
context.AutoRenew = false;
var releaseTask = new Task(() =>
{
blob.ReleaseLease(new AccessCondition() { LeaseId = leaseId });
if (LockReleased != null) LockReleased(lockArgs);
});
if (LockReleaseMode == AzureStorage.LockReleaseMode.Asyncronous)
{
releaseTask.Start();
}
else if (LockReleaseMode == AzureStorage.LockReleaseMode.Syncronous)
{
releaseTask.RunSynchronously();
}
else if (LockReleaseMode == AzureStorage.LockReleaseMode.LetExpire)
{
// Do nothing
}
else
{
throw new NotImplementedException("There should not be a possibility for an else");
}
}
private async Task LockInternal(string lockId, string requestId, Action<LockContext> body, int timeLimitInSeconds, DateTime? timeoutTime)
{
var lockArgs = new LockArgs(lockId, requestId, 1);
if (timeLimitInSeconds > 0 && (timeLimitInSeconds < 16 || timeLimitInSeconds > 59))
{
throw new ArgumentException("timeLimitInSeconds must be at least 16 and no greater than 59");
}
CloudBlockBlob blob = container.GetBlockBlobReference(lockId);
if (blob.Exists() == false)
{
MemoryStream ms = new MemoryStream();
blob.UploadFromStream(ms);
}
var lockContext = new LockContext(blob, null);
bool gotLock = false;
string leaseId = null;
while (gotLock == false)
{
try
{
TimeSpan? maxLeaseTime = null;
if (timeLimitInSeconds > 0) maxLeaseTime = TimeSpan.FromSeconds(timeLimitInSeconds);
string proposedLeaseId = null;
object state = null;
leaseId = await Task<string>.Factory.FromAsync(blob.BeginAcquireLease, blob.EndAcquireLease, maxLeaseTime, proposedLeaseId, state, TaskCreationOptions.None);
lockContext.LeaseId = leaseId;
lockContext.AutoRenew = this.AutoRenew;
lockContext.LockRenewed += (context) => { if (LockRenewed != null) LockRenewed(lockArgs); };
gotLock = true;
if (maxLeaseTime.HasValue)
{
lockContext.LockWarningTimerDuration = maxLeaseTime.Value - ExpiryWarningThreshold;
lockContext.LockWarningTimer = new Timer((o) =>
{
if (LeaseNearExpiry != null) LeaseNearExpiry(lockArgs, lockContext);
}, null, (int)lockContext.LockWarningTimerDuration.TotalMilliseconds, Timeout.Infinite);
}
if (LockAcquired != null) LockAcquired(lockArgs);
body(new LockContext(blob,leaseId));
if(lockContext.LockWarningTimer != null) lockContext.LockWarningTimer.Dispose();
}
catch (StorageException ex)
{
var innerWeb = ex.InnerException as WebException;
if (innerWeb == null) throw;
var response = innerWeb.Response as HttpWebResponse;
if (response == null) throw;
if (response.StatusCode != HttpStatusCode.Conflict) throw;
if (timeoutTime.HasValue && DateTime.UtcNow > timeoutTime.Value)
{
throw GetTimeoutExceptionInternal();
};
}
finally
{
if(gotLock) ReleaseLockInternal(lockArgs, lockContext, blob, leaseId);
}
if (gotLock == false)
{
if (LockWaiting != null) LockWaiting(lockArgs);
lockArgs.AttemptNumber++;
await Task.Delay(PollingInterval);
}
}
}
