We’re excited to announce that the Workflow Foundation (WF) Activity Pack for Windows Azure has just been released! Please refer to our CodePlex page for the download information. The package is also available via NuGet, you can type “Install-Package WFAzureActivityPack” in your package manager console to install the activity pack.

The Activity Pack is built on top of Windows Azure SDK (August Update, 2011). Please install the SDK on your development machine.

Introduction

The WF Activity Pack for Windows Azure CTP 1 is the first community technology preview (CTP) release of Windows Azure activities implementation based on Windows Workflow Foundation in .NET Framework 4.0 (WF4) and Windows Azure SDK. The implementation contains a set of activities based on Windows Azure Storage Service and Windows Azure AppFabric Caching Service, which enables developers to easily access these Azure services within a workflow application.

This Activity Pack includes the following:

For Windows Azure Storage Service - Blob

  • PutBlob creates a new block blob, or replace an existing block blob.
  • GetBlob downloads the binary content of a blob.
  • DeleteBlob deletes a blob if it exists.
  • CopyBlob copies a blob to a destination within the storage account.
  • ListBlobs enumerates the list of blobs under the specified container or a hierarchical blob folder.

For Windows Azure Storage Service - Table

  • InsertEntity<T> inserts a new entity into the specified table.
  • QueryEntities<T> queries entities in a table according to the specified query options.
  • UpdateEntity<T> updates an existing entity in a table.
  • DeleteEntity<T> deletes an existing entity in a table using the specified entity object.
  • DeleteEntity deletes an existing entity in a table using partition and row keys.

For Windows Azure AppFabric Caching Service

  • AddCacheItem adds an object to the cache, or updates an existing object in the cache.
  • GetCacheItem gets an object from the cache as well as its expiration time.
  • RemoveCacheItem removes an object from the cache.

Sample

We’ve prepared a sample for this Activity Pack, which is a simple application for users to upload a file, and view all file entities available in the system. The sample solution is created from the template of Windows Azure Project. Please refer to our CodePlex page for the source code and document of the sample.

Screenshots

Here’s what they look like in Microsoft Visual Studio.

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You can configure the activity in the property grid.

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There are 4 generic activities for Windows Azure Table service, and you need to specify the table entity type when adding them to the designer canvas. The type you specified should inherit from TableServiceEntity.

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Notice

Activities in this Activity Pack don’t have special logics for handling potential exceptions. All exception behaviors are consistent with the Managed Library API provided by the Windows Azure Service. For example, if the GetBlob activity tries to get a blob that doesn’t exist, a StorageClientException will be thrown.

So, please get prepared for the potential exceptions that may occur in the workflow. Today, the simplest approach is to wrap a TryCatch activity outside of the Windows Azure activity.

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For more information on the error handling in Windows Workflow Foundation, please refer to the “Transactions and Error Handling” section in the article “A Developer's Introduction to Windows Workflow Foundation (WF) in .NET 4”.

Feedback

You’re always welcome to send us your thoughts on WF Activity Pack for Windows Azure, and please let us know how we can do it better. You can leave feedback: