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Async asp.net mvc operation out of action

I want to be able to download a user from the cloud database for each request and have it available on request in the controller using asp.net mvc. The problem is that the current structure does not support performing asynchronous operations from action filters. Therefore, OnActionExecuting, OnAuthorization methods do not allow me to do this .. for example, I have the following code that DOES NOT work (so don't try). You get an exception: "Asynchronous module or handler completed while asynchronous operation is not yet completed."

protected async override void OnAuthorization(AuthorizationContext filterContext)
{
  var user = filterContext.HttpContext.User;
  if (!user.Identity.IsAuthenticated)
  {
    HandleUnauthorizedRequest(filterContext);
    return;
  }

  using (var session = MvcApplication.DocumentStore.OpenAsyncSession())
  {
    User currentUser = await session.LoadAsync<User>(user.Identity.Name);
    if (currentUser == null)
    {
      HandleUnauthorizedRequest(filterContext);
      return;
    }

    filterContext.HttpContext.Items["User"] = currentUser;
  }
}

So is there any other way to do this? I noticed that there is a begin execute method in the base controller:

protected override IAsyncResult BeginExecute(RequestContext requestContext, AsyncCallback callback, object state)
{
  return base.BeginExecute(requestContext, callback, state);
}

Can I do it there, maybe?

+5
1

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ParallelExtensionsExtras. :

public class AsyncControllerBase : Controller
{
    protected override IAsyncResult BeginExecute(System.Web.Routing.RequestContext requestContext, AsyncCallback callback, object state)
    {
        return ExecuteCoreAsync(requestContext, state).ToAsync(callback, state);
    }

    protected override void EndExecute(IAsyncResult asyncResult)
    {
        IAsyncResult baseAsyncResult = ((Task<IAsyncResult>)asyncResult).Result;
        base.EndExecute(baseAsyncResult);
    }

    protected virtual async Task<IAsyncResult> ExecuteCoreAsync(System.Web.Routing.RequestContext requestContext, object state)
    {
        await DoStuffHereOrInDerivedClassAsync();

        var baseBeginExecuteCompletion = new TaskCompletionSource<IAsyncResult>();

        AsyncCallback callback = ar =>
        {
            baseBeginExecuteCompletion.SetResult(ar);
        };

        // OnActionExecuting will be called at this point
        var baseAsyncResult = base.BeginExecute(requestContext, callback, state);

        await baseBeginExecuteCompletion.Task;

        return baseAsyncResult;
    }

    protected override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        base.OnActionExecuting(filterContext);
    }
}
+10

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