Multiple telerik MVC grids in TabStrip not working with ninject and entity framework, unit of work, repository pattern - entity-framework

Question

I am creating an ASP.NET MVC 3 e-commerce website and I am currently working on the admin area where you can add/edit products. To create the UI for the product page I am using Telerik MVC controls.
My problem is that when I added a second telerik grid which both retrieve data from the database through an ajax call I receive a couple different errors listed below:
{"There is already an open DataReader associated with this Command
which must be closed first."}
{"The connection was not closed. The connection's current state is
connecting."}
Database Context Code
public interface IUnitOfWork
{
void Commit();
}
public class GSPDataContext : DbContext, IUnitOfWork
{
/* (omitted) IDbSet's for entities */
public GSPDataContext()
: base("GSPConnectionString")
{
}
public virtual IDbSet<T> DbSet<T>() where T : class
{
return Set<T>();
}
public virtual void Commit()
{
base.SaveChanges();
}
}
Generic Repository Code
public class Repository<T> : IRepository<T> where T : class
{
private GSPDataContext m_dataContext;
private readonly IDbSet<T> m_entity;
public Repository(GSPDataContext dataContext)
{
if (dataContext == null)
throw new ArgumentException();
m_dataContext = dataContext;
m_entity = m_dataContext.Set<T>();
}
public T GetById(int id)
{
return this.m_entity.Find(id);
}
public void Insert(T entity)
{
if (entity == null)
throw new ArgumentException();
this.m_entity.Add(entity);
//this.m_dataContext.SaveChanges();
}
public void Delete(T entity)
{
if (entity == null)
throw new ArgumentException();
this.m_entity.Remove(entity);
//this.m_dataContext.SaveChanges();
}
public virtual IQueryable<T> Table
{
get
{
return this.m_entity;
}
}
}
Ninject Code
private static void RegisterServices(IKernel kernel)
{
//Customer
kernel.Bind<IAddressValidationService>().To<AddressValidationService>().InRequestScope();
kernel.Bind<ICustomerService>().To<CustomerService>().InRequestScope();
kernel.Bind<ICustomerProductService>().To<CustomerProductService>().InRequestScope();
//Authentication
kernel.Bind<IOpenIDLoginService>().To<OpenIDLoginService>().InRequestScope();
kernel.Bind<IAuthenticationService>().To<FormsAuthenticationService>().InRequestScope();
//Products
kernel.Bind<IProductService>().To<ProductService>().InRequestScope();
kernel.Bind<IRecentlyViewedProductService>().To<RecentlyViewedProductService>().InRequestScope();
kernel.Bind<IProductPictureService>().To<ProductPictureService>().InRequestScope();
kernel.Bind<ICategoryService>().To<CategoryService>().InRequestScope();
kernel.Bind<IPictureService>().To<PictureService>().InRequestScope();
//Shopping Cart
kernel.Bind<IShoppingCartService>().To<ShoppingCartService>().InRequestScope();
//Shipping and Payment
kernel.Bind<IShippingService>().To<ShippingService>().InRequestScope();
kernel.Bind<IPaymentService>().To<PaymentService>().InRequestScope();
//Orders
kernel.Bind<IOrderCalculationService>().To<OrderCalculationService>().InRequestScope();
kernel.Bind<IOrderProcessingService>().To<OrderProcessingService>().InRequestScope();
kernel.Bind<IOrderService>().To<OrderService>().InRequestScope();
//
kernel.Bind<IEncryptionService>().To<EncryptionService>().InRequestScope();
kernel.Bind<ILogger>().To<LoggingService>().InRequestScope();
kernel.Bind<IWebManager>().To<WebManager>().InRequestScope();
//Messages
kernel.Bind<IEmailService>().To<EmailService>().InRequestScope();
kernel.Bind<IMessageTemplateService>().To<MessageTemplateService>().InRequestScope();
kernel.Bind<IWorkflowMessageService>().To<WorkflowMessageService>().InRequestScope();
//Data
kernel.Bind<GSPDataContext>().ToSelf().InSingletonScope();
kernel.Bind<IUnitOfWork>().ToMethod(ctx => ctx.Kernel.Get<GSPDataContext>()).InSingletonScope();
kernel.Bind(typeof (IRepository<>)).To(typeof (Repository<>)).InRequestScope();
kernel.Bind<IWorkContext>().To<WebWorkContext>().InRequestScope();
}
I suspect it has something to do with how ninject is managing the lifetimes of the various services, but I am not sure what I need to do to make it work.
Any advice would be much appreciated.
Thanks
UPDATE
According to Remo's comment I change my code to the following:
//Data
kernel.Bind<GSPDataContext>().ToSelf().InRequestScope();
kernel.Bind<IUnitOfWork>().ToMethod(ctx => ctx.Kernel.Get<GSPDataContext>()).InRequestScope();
kernel.Bind(typeof (IRepository<>)).To(typeof (Repository<>)).InRequestScope();
And I am now getting the following error:
The ObjectContext instance has been disposed and can no longer be used
for operations that require a connection.
Any ideas?

Answer 1

No, it has nothing to do with how Ninject manages lifetimes. But it has to do how you configured the lifecycles.
It is important that a new DbContext is used for each request. This has to be InRequestScope.