MVC Repository patterns Bind Data - asp.net-mvc

Question

I am having hard time using Repository patterns, is it possible to create two repository patterns?? One for products, another for orders??
I failed to connect these repositories to databases. I know how to work with one repository, but two with IRepository where T: Entity I am getting lost. The question is whether I can create and will not volatile the rules if create ProductRepository and OrderRepository?

Answer 1

Repository pattern is widely used in DDD (Domain-Driven-Design) you could check it here: http://www.infoq.com/minibooks/domain-driven-design-quickly. Also check this book: http://www.amazon.com/Domain-Driven-Design-Tackling-Complexity-Software/dp/0321125215
With regards to your question:
Yes you can use more than 1 repository. Look in this example I use nHibernate session:
// crud operations
public abstract class Repository<T> : IRepository<T> where T : class
{
protected readonly ISession _session;
public Repository(ISession session)
{
_session = session;
}
public T Add(T entity)
{
_session.BeginTransaction();
//_session.SaveOrUpdate(entity);
_session.Save(entity);
_session.Transaction.Commit();
return entity;
}
//...
}
public interface IRepository<T>
{
T Add(T entity);
T Update(T entity);
T SaveOrUpdate(T entity);
bool Delete(T entity);
}
Then my repository looks like this:
public class ProjectRepository : Repository<Project>, IProjectRepository
{
// Project specific operations
}
public interface IProjectRepository : IRepository<Project>
{
Project Add(Project entity);
Project Update(Project entity);
Project find_by_id(int id);
Project find_by_id_and_user(int id, int user_id);
//..
}
Then using Ninject:
Global.asax.cs
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterGlobalFilters(GlobalFilters.Filters);
RegisterRoutes(RouteTable.Routes);
ControllerBuilder.Current.SetControllerFactory(new NinjectControllerFactory());
}
Then in NinjectControllerFactory I load the modules:
public class NinjectControllerFactory : DefaultControllerFactory
{
private IKernel kernel = new StandardKernel(new NhibernateModule(), new RepositoryModule(), new DomainServiceModule());
protected override IController GetControllerInstance(RequestContext context, Type controllerType)
{
//var bindings = kernel.GetBindings(typeof(IUserService));
if (controllerType == null)
return null;
return (IController)kernel.Get(controllerType);
}
}
NhibernateModule:
public class NhibernateModule : NinjectModule
{
public override void Load()
{
string connectionString =
ConfigurationManager.ConnectionStrings["sqlite_con"].ConnectionString;
var helper = new NHibernateHelper(connectionString);
Bind<ISessionFactory>().ToConstant(helper.SessionFactory).InSingletonScope();
Bind<ISession>().ToMethod(context => context.Kernel.Get<ISessionFactory>().OpenSession()).InRequestScope();
}
}
Then in RepositoryModule I use Ninject Conventions to automatically bind all repositories with their interfaces:
using Ninject.Extensions.Conventions;
public class RepositoryModule : NinjectModule
{
public override void Load()
{
IKernel ninjectKernel = this.Kernel;
ninjectKernel.Scan(kernel =>
{
kernel.FromAssemblyContaining<ProjectRepository>();
kernel.BindWithDefaultConventions();
kernel.AutoLoadModules();
kernel.InRequestScope();
});
}
}
And in the end I basically inject Repository in the controller:
public class projectscontroller : basecontroller
{
private readonly IProjectRepository _projectRepository;
public projectscontroller(IProjectRepository projectRepository)
{
_projectRepository = projectRepository;
}
[AcceptVerbs(HttpVerbs.Get)]
[Authorize]
public ActionResult my()
{
int user_id = (User as CustomPrincipal).user_id;
var projectList = _projectRepository.find_by_user_order_by_date(user_id);
var projetsModel = new ProjectListViewModel(projectList);
return View("my", projetsModel);
}
}
This way you just create new Repository and its Interface and it will be automatically injected to your controller.