ASP.NET Identity and Windows Azure Table Storage

In case you haven’t heard, ASP.NET Identity is the new kid on the block for handling user identity, and replaces ASP.NET Membership, Simple Membership and Universal Membership. It is built on top of OWIN which positions it well for the future of ASP.NET. If you’re not familiar with ASP.NET Identity then check out Introduction to ASP.NET Identity by Pranav Rastogi or the posts by K. Scott Allen linked to at the bottom of the post.

In this post I’ll look at how to use Windows Azure Table Storage with ASP.NET Identity. One of the main objectives will be to make it easy to get started with using Table Storage with a web application created using the new templates in Visual Studio 2013.


Getting up and running

You will need to have a Windows Azure Storage account and an associated storage connection string . If you haven’t got a connection string then follow the instructions in How to use the Table Storage Service (see “Create a Windows Azure Storage Account” and “Setup a storage connection string”).

Armed with you storage connection string, start up Visual Studio 2013 and create a new ASP.NET Project with ASP.NET MVC:


Once the project has been created, open up Controllers\AccountController.cs. Notice that there is a using directive for Microsoft.AspNet.Identity.EntityFramework – this is the namespace that contains the default, Entity Framework implementation of the UserStore. The UserStore is created in the default constructor:

 public AccountController()     : this(
        new UserManager<ApplicationUser>(
            new UserStore<ApplicationUser>(
                new ApplicationDbContext())))

Next we’ll install the NuGet package with the sample Table Storage implementation of UserStore. In the NuGet Package Manager Console (Under Tools\Library Package Manager), type

 Install-Package leeksnet.AspNet.Identity.TableStorage

This will ensure that you have the Table Storage libraries as well as the sample UserStore for TableStorage. Now we just need to update the application to use it.

In AccountController, remove the using Microsoft.AspNet.Identity.EntityFramework and instead, add

 using System.Configuration;
using leeksnet.AspNet.Identity.TableStorage;

Now update the constructor we saw above:

 public AccountController()     
  : this(
         new UserManager<ApplicationUser>(
             new UserStore<ApplicationUser>(
                 id => id.GetHashCode().ToString(CultureInfo.InvariantCulture) 

We could have hard-coded the storage connection string in code, but it’s handy to have it in config as we can transform the setting when we publish. So we could use development storage locally, and the real Table Storage service when we deploy.

It’s also worth commenting on the lambda expression in the code above. When working with Table Storage, partition keys need to be considered. Partition Keys are an important part of how you scale Table Storage usage, but also how you enable querying of related data. For simplicity I’ve used the hashcode of the user id, but you can pick whatever strategy you want. If you wanted a fixed number of partitions, 10 say, you could use id%10 as the partition key.

Finally, add the your storage connection string to the web.config under the connectionStrings element, replacing the actual connection string with the one for your storage account. (And yes, I have regenerated my key since pasting it here!)

 <add name="IdentityStore" 

Other Thoughts

Please note that this is a sample library and hasn’t been written with production usage in mind :-) My goal was to demonstrate how you could get started using Azure Table Storage with ASP.NET Identity. Not all of the ASP.NET Identity functionality is implemented, e.g. IUserClaimStore, IUserRoleStore. The implementation also couples the user ID and the user name as this simplifies the persistence a little – feel free to change it if that doesn’t suit you ;-) The source code is available at:

If you haven’t got the Windows Azure SDK installed, then it is worth grabbing. Version 2.2 makes it simple to connect to your subscription, and you can view and update Table Storage contents (as well as obtaining storage connection strings) – see the announcement post for more details.

Further reading

If you want to read more about ASP.NET Identity then check out the site.

K. Scott Allen nice also has a nice set of posts: