The addition of new features for Windows Azure Storage is the latest step in the evolution of Microsoft's Cloud operating system. Starting with the end of the past month, Azure testers can enjoy Entity Group Transactions for Windows Azure Table, Copy Blob for Windows Azure Blob, Get Block List for Windows Azure Blob and API Versioning. Brad Calder, Windows Azure Storage, explained that the new features introduced to Azure Storage were limited to the Windows Azure Storage REST interface and ADO.NET client library. However, the plan is to include the refreshes into a future version of the Azure software development kit.

“It is now possible to perform a transaction across entities stored within the same table and same partition (i.e., entities having the same partition key value) (...),” Calder explained. “We now allow applications to copy a blob from a source blob to a destination blob within the same storage account. (...) We have added the ability to GetBlockList to retrieve the uncommitted block list, as well as the committed block list. (...) For all of the Windows Azure Storage solutions we have introduced a new HTTP header called “x-ms-version.” All changes to the storage APIs will be versioned by this header.

The reason why the Windows Azure SDK does not yet support the new features of the Cloud platform is Microsoft's focus on an agile release process. The software giant is looking to deliver the features as fast as possible via the REST interface, and only later make the Azure SDK and the sample storage client library play nice with them. Last week, Microsoft also made available for download the May 2009, Community Technology Preview (CTP) of the Windows Azure SDK and the Windows Azure Tools for Visual Studio.

“There are two additional changes to the semantics of Windows Azure Tables: Property Names – We now support C# Unicode characters for the property names. With this change we no longer support “-“, since it is not supported by ADO.NET data services,” Calder added. “PartitionKey and RowKey sizes – The PartitionKey and RowKey have a limit of 1K of characters each. Originally, we had documented that these could be up to 64KB, but there was a bug in the CTP release that actually limited these to less than 256 characters. With this release the limit is now 1K characters each.”


Windows Azure Tools for Microsoft Visual Studio May 2009 CTP is available for download here.

Windows Azure Software Development Kit (May 2009 CTP) is available for download here.

Visual Studio 2010 Beta 1 is available for download here.