public TEntity AddOrUpdate(TKey key, Func <TEntity> addViewFactory, Func <TEntity, TEntity> updateViewFactory,
AddOrUpdateHint hint)
{
string etag = null;
var blob = GetBlobReference(key);
TEntity view;
try
{
// atomic entities should be small, so we can use the simple method
var bytes = blob.DownloadByteArray();
using (var stream = new MemoryStream(bytes))
{
view = _strategy.Deserialize <TEntity>(stream);
}
view = updateViewFactory(view);
etag = blob.Attributes.Properties.ETag;
}
catch (StorageClientException ex)
{
switch (ex.ErrorCode)
{
case StorageErrorCode.ContainerNotFound:
var s = string.Format(
"Container '{0}' does not exist. You need to initialize this atomic storage and ensure that '{1}' is known to '{2}'.",
blob.Container.Name, typeof(TEntity).Name, _strategy.GetType().Name);
throw new InvalidOperationException(s, ex);
case StorageErrorCode.BlobNotFound:
case StorageErrorCode.ResourceNotFound:
view = addViewFactory();
break;
default:
throw;
}
}
// atomic entities should be small, so we can use the simple method
// http://toolheaven.net/post/Azure-and-blob-write-performance.aspx
using (var memory = new MemoryStream())
{
_strategy.Serialize(view, memory);
// note that upload from stream does weird things
var bro = etag != null
? new BlobRequestOptions {
AccessCondition = AccessCondition.IfMatch(etag)
}
: new BlobRequestOptions {
AccessCondition = AccessCondition.IfNoneMatch("*")
};
// make sure that upload is not rejected due to cashed content MD5
// http://social.msdn.microsoft.com/Forums/hu-HU/windowsazuredata/thread/4764e38f-b200-4efe-ada2-7de442dc4452
blob.Properties.ContentMD5 = null;
blob.UploadByteArray(memory.ToArray(), bro);
}
return(view);
}
public AutoRenewLease(CloudBlob blob)
{
this.blob = blob;
blob.Container.CreateIfNotExist();
try
{
blob.UploadByteArray(new byte[0], new BlobRequestOptions {
AccessCondition = AccessCondition.IfNoneMatch("*")
});
}
catch (StorageClientException e)
{
if (e.ErrorCode != StorageErrorCode.BlobAlreadyExists &&
e.StatusCode != HttpStatusCode.PreconditionFailed) // 412 from trying to modify a blob that's leased
{
throw;
}
}
leaseId = blob.TryAcquireLease();
if (HasLease)
{
renewalThread = new Thread(() =>
{
while (true)
{
Thread.Sleep(TimeSpan.FromSeconds(40));
blob.RenewLease(leaseId);
}
});
renewalThread.Start();
}
}
private BlobRequestOptions CreateBlobRequestOptions()
{
var etag = this.Properties.ETag;
var options = new BlobRequestOptions();
options.AccessCondition = etag == null?
AccessCondition.IfNoneMatch("*") :
AccessCondition.IfMatch(etag);
return(options);
}
public AutoRenewLease(ILoggerFactory loggerFactory, LoggerLevel logLevel, CloudBlob blob, int renewLeaseSeconds = 40, int leaseLengthSeconds = 90)
{
_logger = loggerFactory.Create(GetType(), logLevel);
var autoRenewLease = this;
_blob = blob;
blob.Container.CreateIfNotExist();
try
{
blob.UploadByteArray(new byte[0], new BlobRequestOptions {
AccessCondition = AccessCondition.IfNoneMatch("*")
});
}
catch (StorageClientException ex)
{
if (ex.ErrorCode != StorageErrorCode.BlobAlreadyExists)
{
if (ex.StatusCode != HttpStatusCode.PreconditionFailed)
{
throw;
}
}
}
LeaseId = blob.TryAcquireLease(leaseLengthSeconds);
if (!HasLease)
{
return;
}
_cancellationTokenSource = new CancellationTokenSource();
_resetEvent = new ManualResetEvent(false);
Task.Factory.StartNew(() =>
{
try
{
while (true)
{
_resetEvent.WaitOne(TimeSpan.FromSeconds(renewLeaseSeconds));
if (_cancellationTokenSource.IsCancellationRequested)
{
break;
}
blob.RenewLease(autoRenewLease.LeaseId);
}
}
catch (Exception e)
{
LeaseId = null; // Release the lease
_logger.Error("Error renewing blob lease", e);
}
}, _cancellationTokenSource.Token);
}
private static void CreateIfNotExist(this CloudBlob blob)
{
try
{
blob.UploadByteArray(new byte[0], new BlobRequestOptions {
AccessCondition = AccessCondition.IfNoneMatch("*")
});
}
catch (StorageClientException ex)
{
if (ex.ErrorCode != StorageErrorCode.BlobAlreadyExists && ex.StatusCode != HttpStatusCode.PreconditionFailed)
{
throw;
}
}
}
public static AutoRenewLease GetOrThrow(CloudBlob blob)
{
blob.Container.CreateIfNotExist();
// Create lock blob
try
{
var requestOptions = new BlobRequestOptions
{
AccessCondition = AccessCondition.IfNoneMatch("*")
};
blob.UploadByteArray(new byte[0], requestOptions);
}
catch (StorageClientException e)
{
if (e.ErrorCode != StorageErrorCode.BlobAlreadyExists &&
e.StatusCode != HttpStatusCode.PreconditionFailed)
// 412 from trying to modify a blob that's leased
{
throw;
}
}
string leaseId = null;
var ex = DoUntilTrue(Try4Times, CancellationToken.None, () =>
{
leaseId = AcquireLease(blob);
return(!String.IsNullOrEmpty(leaseId));
});
if (ex != null)
{
throw new InvalidOperationException("Failed to get lease", ex);
}
// Either we get lease or throw timeout exception
if (String.IsNullOrEmpty(leaseId))
{
throw new InvalidOperationException();
}
return(new AutoRenewLease(blob, leaseId));
}
static AccessCondition MapCondition(StreamingCondition condition)
{
switch (condition.Type)
{
case StreamingConditionType.None:
return(AccessCondition.None);
case StreamingConditionType.IfMatch:
var x = ExposeException(condition.ETag, "'ETag' should be present");
return(AccessCondition.IfMatch(x));
case StreamingConditionType.IfNoneMatch:
var etag = ExposeException(condition.ETag, "'ETag' should be present");
return(AccessCondition.IfNoneMatch(etag));
default:
throw new ArgumentOutOfRangeException();
}
}
public bool SetIfNotExists(T obj)
{
BlobRequestOptions reqOpt = new BlobRequestOptions();
reqOpt.AccessCondition = AccessCondition.IfNoneMatch("*");
try
{
using (MemoryStream stream = new MemoryStream())
{
Serializer.Serialize(stream, obj);
stream.Seek(0, SeekOrigin.Begin);
blob.UploadFromStream(stream, reqOpt);
}
return(true);
}
catch (StorageClientException e)
{
if (e.ErrorCode != StorageErrorCode.ConditionFailed && e.ErrorCode != StorageErrorCode.BlobAlreadyExists)
{
throw;
}
return(false);
}
}
