Adding forms authentication (SimpleMembership) to webapi app - asp.net-mvc-4

Question

I'm trying to add to a MVC4 webapi project the simple membership provider authentication mechanism found in a MVC 4 web application project, for a hybrid application serving its pages with a rich JS content, which uses AJAX calls to webapi actions to perform its tasks. I need the app users to authenticate before they can work with the apps provided in these pages, so I think I'll be fine with the forms authentication. I thus need to add it to the existing WebApi project and let my authorized-only actions return a 302 (redirect user to login page) rather than a 401.
Anyway, I'm missing something because as soon as I try to use a WebSecurity method I get the following exception:
System.InvalidOperationException was caught
Message=To call this method, the "Membership.Provider" property must be an instance of "ExtendedMembershipProvider".
Source=WebMatrix.WebData
Could anyone suggest a fix? Here are the steps I took for adding authorization:
1) Web.config: add to system.web:
<authentication mode="Forms">
<forms loginUrl="~/Account/Login" timeout="2880" />
</authentication>
Add to appsettings (the 2nd entry is for replacing 401 with 302):
<add key="enableSimpleMembership" value="true"/>
<add key="webapi:EnableSuppressRedirect" value="false" />
Also remove profile, membership and rolemanager sections from the original template (they are not intended to be used with simple membership).
2) add NuGet packages for OpenAuth (DotNetOpenAuth Core, DotNetOpenAuth ext for ASP.NET, DotNetOpenAuth 1.0(a) consumer, DotNetOpenAuth 1.0(a), DotNetOpenAuth OpenID Core, DotNetOpenAuth OpenID Relying Party).
3) add InitializeSimpleMembership.cs to Filters (the code is pretty standard, see below).
4) copy from an MVC web app project the models in AccountModels.cs, all the views in Views/Account, and the AccountController.cs.
The InitializeSimpleMembership code is here:
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
public sealed class InitializeSimpleMembershipAttribute : ActionFilterAttribute
{
private static SimpleMembershipInitializer _initializer;
private static object _initializerLock = new object();
private static bool _isInitialized;
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
LazyInitializer.EnsureInitialized(ref _initializer, ref _isInitialized, ref _initializerLock);
}
private class SimpleMembershipInitializer
{
private static void SeedData()
{
// seed data: users and roles
if (!WebSecurity.UserExists("TheAdminGuyName"))
WebSecurity.CreateUserAndAccount("TheAdminGuyName", "password");
if (!Roles.RoleExists("administrator")) Roles.CreateRole("administrator");
if (!Roles.IsUserInRole("TheAdminGuyName", "administrator"))
Roles.AddUserToRole("TheAdminGuyName", "administrator");
}
public SimpleMembershipInitializer()
{
Database.SetInitializer<UsersContext>(null);
try
{
using (var context = new UsersContext())
{
if (!context.Database.Exists())
{
((IObjectContextAdapter)context).ObjectContext.CreateDatabase();
}
}
WebSecurity.InitializeDatabaseConnection("DefaultConnection", "User", "UserId", "UserName", autoCreateTables: true);
SeedData();
}
catch (Exception ex)
{
throw new InvalidOperationException("The ASP.NET Simple Membership database could not be initialized. For more information, please see http://go.microsoft.com/fwlink/?LinkId=256588", ex);
}
}
}
}

Answer 1

This might be relevant, as it mentions your error specifically:
http://weblogs.asp.net/jgalloway/archive/2012/08/29/simplemembership-membership-providers-universal-providers-and-the-new-asp-net-4-5-web-forms-and-asp-net-mvc-4-templates.aspx