Change Ninject to Autofac equivalent for Asp MVC - asp.net-mvc

I have next code and I would like to replace it to Autofac.
what should I do ?
public class NinjectKernelFactory
{
public IKernel Create()
{
return LoadAssembliesIntoKernel(new StandardKernel());
}
private IKernel LoadAssembliesIntoKernel(IKernel kernel)
{
foreach (Assembly assembly in AppDomain.CurrentDomain.GetAssemblies())
{
try
{
kernel.Load(assembly);
}
catch (Exception)
{
//Empty Catch used because ninject have problem
//with loading some of the Sitecore MVC assemblies.
// Method .ToString()
}
}
return kernel;
}
}
public class NinjectControllerFactory : DefaultControllerFactory
{
private IKernel _kernel;
public NinjectControllerFactory(IKernel kernel)
{
_kernel = kernel;
}
public override void ReleaseController(IController controller)
{
_kernel.Release(controller);
}
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
return (IController)_kernel.Get(controllerType);
}
}

The kernel.Load method of Ninject will load all class that implement INinjectModule from the assembly.
The equivalent in Autofac is to use the RegisterAssemblyModules method which will load all class that implement IModule.
var builder = new ContainerBuilder();
IEnumerable<Assembly> assemblies = AppDomain.CurrentDomain.GetAssemblies();
if (HostingEnvironment.InClientBuildManager)
{
assemblies = assemblies.Union(BuildManager.GetReferencedAssemblies()
.Cast<Assembly>())
.Distinct();
}
builder.RegisterAssemblyModules(assemblies);
I use BuildManager.GetReferencedAssemblies() to avoid issue after ASP.net recycling process. See IIS Hosted Web Application on autofac documentation for more explanation.

Related

How to use Dependency Injection with a Controller

I have below code which will work without any issue
MAUserController.cs
public class MAUserController : ApiController
{
ILogService loggerService;
IMAUserService _service;
public MAUserController(ILogService loggerService, IMAUserService Service)
{
this.loggerService = loggerService;
this._service = Service;
}
}
DependencyInstaller.cs
public class DependencyInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register(
Component.For<ILogService>().ImplementedBy<LogService>().LifeStyle.PerWebRequest,
Component.For<IDatabaseFactory>().ImplementedBy<DatabaseFactory>().LifeStyle.PerWebRequest,
Component.For<IUnitOfWork>().ImplementedBy<UnitOfWork>().LifeStyle.PerWebRequest,
AllTypes.FromThisAssembly().BasedOn<IHttpController>().LifestyleTransient(),
AllTypes.FromAssemblyNamed("ISOS.Health.Service").Where(type => type.Name.EndsWith("Service")).WithServiceAllInterfaces().LifestylePerWebRequest(),
AllTypes.FromAssemblyNamed("ISOS.Health.Repository").Where(type => type.Name.EndsWith("Repository")).WithServiceAllInterfaces().LifestylePerWebRequest()
);
}
}
If I am using normal Controller instead ApiController then it gives me an error
UserController.cs
public class UserController : Controller
{
ILogService loggerService;
IMAUserService _service;
public UserController(ILogService loggerService, IMAUserService Service)
{
this.loggerService = loggerService;
this._service = Service;
}
}
This will give an error:
No parameterless constructor defined for this object
I am using CastleDI Windsor for Dependency injection.
Do I need to do anything or register something?
FIRST APPROACH
Advice: Use with caution, because it may cause memory leaks for Castle Windsor.
You have to create a controller activator, which should implement the IControllerActivator interface, in order to use your DI container to create the controller instances:
public class MyWindsorControllerActivator : IControllerActivator
{
public MyWindsorControllerActivator(IWindsorContainer container)
{
_container = container;
}
private IWindsorContainer _container;
public IController Create(RequestContext requestContext, Type controllerType)
{
return _container.Resolve(controllerType) as IController;
}
}
Then, add this class to your DependencyInstaller:
public class DependencyInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register(
// Current code...
Component.For<IControllerActivator>()
.ImplementedBy<MyWindsorControllerActivator>()
.DependsOn(Dependency.OnValue("container", container))
.LifestyleSingleton();
);
}
}
Also, create your own dependency resolver based on the Windsor container:
public class MyWindsorDependencyResolver : IDependencyResolver
{
public MyWindsorDependencyResolver(IWindsorContainer container)
{
_container = container;
}
private IWindsorContainer _container;
public object GetService(Type serviceType)
{
return _container.Resolve(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
return _container.ResolveAll(serviceType).Cast<object>();
}
}
Then, finally, register your dependency resolver in the Application_Start method in Global.asax.cs:
DependencyResolver.SetResolver(new MyWindsorDependencyResolver(windsorContainer));
This way, when MVC requires the controller activator through it's dependency resolver, it will get ours, which will use our Windsor container to create the controllers with all it's dependencies.
In order to avoid memory leaks using IControllerActivator, the easiest solution will be to use lifestyles like per thread or per web request, rather than the default (Singleton), transient and pooled, for the registered components. Check this link for more info about how to avoid memory leaks using Castle Windsor Container.
SECOND APPROACH
However, as pointed out by #PhilDegenhardt, a much better and correct approach will be to implement a custom controller factory, in order to be able to release the controller component created by the Castle Windsor DI Container. Here you can find an example (see the section about Dependency Injection).
Taken from that example, the implementation could be:
Global.asax.cs:
public class MvcApplication : System.Web.HttpApplication
{
private WindsorContainer _windsorContainer;
protected void Application_Start()
{
var _windsorContainer = new WindsorContainer();
_windsorContainer.Install(
new DependencyInstaller(),
// Other installers...
);
ControllerBuilder.Current.SetControllerFactory(new WindsorControllerFactory(_windsorContainer.Kernel));
}
protected void Application_End()
{
if (_windsorContainer != null)
{
_windsorContainer.Dispose();
}
}
}
WindsorControllerFactory.cs:
public class WindsorControllerFactory : DefaultControllerFactory
{
private readonly IKernel _kernel;
public WindsorControllerFactory(IKernel kernel)
{
_kernel = kernel;
}
public override void ReleaseController(IController controller)
{
_kernel.ReleaseComponent(controller); // The important part: release the component
}
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
if (controllerType == null)
{
throw new HttpException(404, string.Format("The controller for path '{0}' could not be found.", requestContext.HttpContext.Request.Path));
}
return (IController)_kernel.Resolve(controllerType);
}
}
Look at the following project link https://github.com/rarous/Castle.Windsor.Web.Mvc
Add this reference via NuGet to your MVC project, it will do the registering job for you.
Do not forget to catch your errors in global.asax.cs!
Registration :
container.Register(Component.For<IControllerFactory>().ImplementedBy<WindsorControllerFactory>());
Implementation of MVC controller factory :
using System;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;
using Castle.MicroKernel;
namespace Installer.Mvc
{
public class WindsorControllerFactory : DefaultControllerFactory
{
private readonly IKernel _kernel;
public WindsorControllerFactory(IKernel kernel)
{
_kernel = kernel;
}
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
if (controllerType == null)
{
throw new HttpException(404, string.Format("The controller for path '{0}' could not be found.", requestContext.HttpContext.Request.Path));
}
if (_kernel.GetHandler(controllerType) != null)
{
return (IController)_kernel.Resolve(controllerType);
}
return base.GetControllerInstance(requestContext, controllerType);
}
public override void ReleaseController(IController controller)
{
_kernel.ReleaseComponent(controller);
}
}
}

Setting up Inversion of Control (IoC) in ASP.NET MVC with Castle Windsor

I'm going over Sanderson's Pro ASP.NET MVC Framework and in Chapter 4 he discusses Creating a Custom Controller Factory and it seems that the original method, AddComponentLifeStyle or AddComponentWithLifeStyle, used to register controllers is deprecated now:
public class WindsorControllerFactory : DefaultControllerFactory
{
IWindsorContainer container;
public WindsorControllerFactory()
{
container = new WindsorContainer(new XmlInterpreter(new ConfigResource("castle")));
// register all the controller types as transient
var controllerTypes = from t in Assembly.GetExecutingAssembly().GetTypes()
where typeof(IController).IsAssignableFrom(t)
select t;
//[Obsolete("Use Register(Component.For<I>().ImplementedBy<T>().Named(key).Lifestyle.Is(lifestyle)) instead.")]
//IWindsorContainer AddComponentLifeStyle<I, T>(string key, LifestyleType lifestyle) where T : class;
foreach (Type t in controllerTypes)
{
container.Register(Component.For<IController>().ImplementedBy<???>().Named(t.FullName).LifeStyle.Is(LifestyleType.Transient));
}
}
// Constructs the controller instance needed to service each request
protected override IController GetControllerInstance(Type controllerType)
{
return (IController)container.Resolve(controllerType);
}
}
The new suggestion is to use Register(Component.For<I>().ImplementedBy<T>().Named(key).Lifestyle.Is(lifestyle)), but I can't figure out how to present the implementing controller type in the ImplementedBy<???>() method. I tried ImplementedBy<t>() and ImplementedBy<typeof(t)>(), but I can't find the appropriate way to pass in the implementing type. Any ideas?
I'm doing this using the ControllerBuilder.SetControllerFactory and the code you can find in the open source project MvcContrib:
Global.asax.cs
protected void Application_Start()
{
...
IWindsorContainer windsorContainer = new WindsorContainer();
windsorContainer.RegisterControllers(Assembly.GetExecutingAssembly());
ControllerBuilder.Current.SetControllerFactory(new WindsorControllerFactory(windsorContainer));
...
}
WindsorControllerFactory
public class WindsorControllerFactory : DefaultControllerFactory
{
private readonly IWindsorContainer _container;
public WindsorControllerFactory(IWindsorContainer container)
{
if (container == null)
{
throw new ArgumentNullException();
}
_container = container;
}
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
if (controllerType == null)
{
throw new HttpException();
}
if (!typeof(IController).IsAssignableFrom(controllerType))
{
throw new ArgumentException();
}
try
{
return (IController)_container.Resolve(controllerType);
}
catch (Exception ex)
{
throw new InvalidOperationException();
}
}
public override void ReleaseController(IController controller)
{
IDisposable disposable = controller as IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
_container.Release(controller);
}
}
WindsorExtensions (see MvcContrib)
public static class WindsorExtensions
{
public static IWindsorContainer RegisterController<T>(this IWindsorContainer container) where T : IController
{
container.RegisterControllers(typeof(T));
return container;
}
public static IWindsorContainer RegisterControllers(this IWindsorContainer container, params Type[] controllerTypes)
{
foreach (Type type in controllerTypes)
{
if (ControllerExtensions.IsController(type))
{
container.Register(Component.For(type).Named(type.FullName).LifeStyle.Is(LifestyleType.Transient));
}
}
return container;
}
public static IWindsorContainer RegisterControllers(this IWindsorContainer container, params Assembly[] assemblies)
{
foreach (Assembly assembly in assemblies)
{
container.RegisterControllers(assembly.GetExportedTypes());
}
return container;
}
}
ControllerExtensions (see MvcContrib)
public static class ControllerExtensions
{
public static bool IsController(Type type)
{
return type != null
&& type.Name.EndsWith("Controller", StringComparison.OrdinalIgnoreCase)
&& !type.IsAbstract
&& typeof(IController).IsAssignableFrom(type);
}
}
You may also want to consider using the new installer option in the latest Windsor build. There is more documentation on Windsor's tutorial: http://stw.castleproject.org/Windsor.Windsor-tutorial-part-three-writing-your-first-installer.ashx
There's a tutorial (in the works but 9 parts are already out) that discusses usage of Windsor in ASP.NET MVC here.
That's the most up to date and covering most of the usual usage resource on the topic as far as I'm aware.
#Lirik, as an addition: drop your own custom IControllerFactory out if you use MVC3. Just register controllers with Windsor and implement IDependencyResolver with Windsor container inside.
Set your IDependencyResolver as MVC DependencyResolver and DefaultControllerFactory will automatically wire up controllers registered in container (via DependencyResolver).
something like:
public void Register(IWindsorContainer container)
{
Assembly.GetAssembly(typeof(ControllersRegistrarMarker)).GetExportedTypes()
.Where(IsController)
.Each(type => container.AddComponentLifeStyle(
type.Name.ToLower(),
type,
LifestyleType.Transient));
}
ControllersRegistrarMarker is just an empty class in your Controllers assembly

Ninject doesn't call Dispose on objects when out of scope

I was surprised to find that at least one of my objects created by Ninject is not disposed of at the end of the request, when it has been defined to be InRequestScope
Here's the object I'm trying to dispose:
Interface:
public interface IDataContext : IDisposable
{
MessengerEntities context { get; set; }
}
MessengerEntities is Entity Framework's implementation of ObjectContext -- my context object.
Then I create a concrete class like so:
public class DataContext : IDataContext
{
private MessengerEntities _context = new MessengerEntities();
public MessengerEntities context
{
get
{
return _context;
}
set
{
_context = value;
}
}
#region IDisposable Members
public void Dispose()
{
context.Dispose();
}
#endregion
}
And then I have a Ninject controller factory like so (this is modeled on the Steve Sanderson MVC 2 book):
public class NinjectControllerFactory : DefaultControllerFactory
{
// a Ninject "kernel" is the thing that can supply object instances
private IKernel kernel = new StandardKernel(new MessengerServices());
// ASP.NET MVC calls this to get the controller for each request
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
if (controllerType == null)
return null;
return (IController)kernel.Get(controllerType);
}
private class MessengerServices : NinjectModule
{
public override void Load()
{
Bind<IDataContext>().To<DataContext>().InRequestScope();
Bind<IArchivesRepository>().To<ArchivesRepository>().InRequestScope();
Bind<IMessagesRepository>().To<MessagesRepository>().InRequestScope();
}
}
}
Now, when I put a breakpoint at the call to context.Dispose() in the DataContext object and run the debugger, that code never gets executed.
So, the evidence suggests that Ninject does not dispose of objects when they go out of scope, but simply creates new objects and relies on the garbage collector to get rid of them at a time of its choosing.
My question is: should I be concerned about this? Because I am -- I would think Ninject would dispose of any object that implements IDisposable.
UPDATE: I downloaded the Ninject Mvc extensions (for MVC 3) and this is now how I'm doing the MvcApplication and the binding, and it does seem to be disposing of my context object.
In global.asax:
public class MvcApplication : NinjectHttpApplication
{
public static void RegisterGlobalFilters(GlobalFilterCollection filters)
{
filters.Add(new HandleErrorAttribute());
}
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
}
protected override Ninject.IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Load(Assembly.GetExecutingAssembly());
return kernel;
}
protected override void OnApplicationStarted()
{
base.OnApplicationStarted();
AreaRegistration.RegisterAllAreas();
RegisterGlobalFilters(GlobalFilters.Filters);
RegisterRoutes(RouteTable.Routes);
}
}
and
public class EFBindingModule : NinjectModule
{
public override void Load()
{
Bind<IDataContext>().To<DataContext>().InRequestScope();
Bind<IArchivesRepository>().To<ArchivesRepository>().InRequestScope();
Bind<IMessagesRepository>().To<MessagesRepository>().InRequestScope();
}
}
Everything else remains the same.
Ninject will dispose your objects as soon as the request object is collected by the GC. But normally this takes some time. But there is a way to force early disposal after the request ended. The best way is to use Ninject.Web.MVC http://www.planetgeek.ch/2010/11/13/official-ninject-mvc-extension-gets-support-for-mvc3/ instead of implementing your own ControllerFactory. The other way is to configure your application to use the OnePerRequestModule.

MVC 3 + IoC + NInject + Repositories + LINQ

I'm trying to work with NInject in my MVC 3 application, and i have one question.
Interface
public interface ITalesRepository
{
IEnumerable<Tale> GetAllTales();
}
Repository
public class TalesRepository : ITalesRepository
{
private FairyTalesMVC3DataContext _dataContext;
public TalesRepository(FairyTalesMVC3DataContext dataContext)
{
_dataContext = dataContext;
}
public IEnumerable<Tale> GetAllTales()
{
return _dataContext.Tales.OrderBy(c => c.NameAn);
}
}
Home controller
public class HomeController : Controller
{
private readonly ITalesRepository _talesRepository;
public HomeController(ITalesRepository talesRepository)
{
_talesRepository = talesRepository;
}
public ActionResult Index()
{
ViewBag.Tales = _talesRepository.GetAllTales();
return View();
}
}
So, i need to initialize my TalesRepository with DataContext, and now it is so:
private void RegisterDependencyResolver()
{
var kernel = new StandardKernel();
kernel.Bind<ITalesRepository>().To<TalesRepository>().WithConstructorArgument("dataContext", new FairyTalesMVC3DataContext(ConfigurationManager.ConnectionStrings["dbFairyTalesConnectionString"].ConnectionString));
DependencyResolver.SetResolver(new NinjectDependencyResolver(kernel));
}
So, my question, is it ok or something wrong?
First of all:
public IEnumerable<Tale> GetAllTales()
{
return _dataContext.Tales.OrderBy(c => c.NameAn);
}
I would add .ToList() to the end. Else you'll get data layer exceptions in your presentation layer which is not fine.
Next, I would recommend that you switch to ViewModels instead of using ViewBag. It's a lot easier to prevent that logic leaks into the views if you are using ViewModels. Since you can add the logic to the ViewModel and thus get the same behaviour in all views using the model.
Your application should inherit from NinjectHttpApplication. It registers dependency resolver, so you don't have to do it.
You should also override CreateKernel in application class and register your own module with bindings:
public class MvcApplication : NinjectHttpApplication
{
protected override IKernel CreateKernel()
{
return new StandardKernel(new INinjectModule[] {new MvcModule()});
}
}
public class MvcModule : NinjectModule
{
public override void Load()
{
Bind<ITalesRepository>().To<TalesRepository>();
Bind<FairyTalesMVC3DataContext>().To<FairyTalesMVC3DataContext>().InRequestScope();
}
}

ASP MVC 2 Ninject

I'm trying to learn a bit about MVC and have come across a problem when using Ninject. I want to bind repositories but keep getting the 'Object reference not set to an instance of an object' error.
I have created my NinjectControllerFactory:
public class NinjectControllerFactory : DefaultControllerFactory
{
// A Ninject "kernel" is the thing that can supply object instances
private IKernel kernel = new StandardKernel(new SportsShopServices());
// ASP .NET MVC calls this to get the controller for each request
protected override IController GetControllerInstance(RequestContext context, Type controllerType)
{
if (controllerType == null)
return null;
return (IController) kernel.Get(controllerType);
}
// Configure how abstract sevice types are mapped to concrete implementations
private class SportsShopServices : NinjectModule
{
public override void Load()
{
Bind<IProductRepository>().To<SqlProductsRepository>()
.WithConstructorArgument("connectionString",
ConfigurationManager.ConnectionStrings["AppDb"].ConnectionString);
}
}
}
and my controller :
public class ProductsController : Controller
{
private IProductRepository productsRepository;
// Constructor used with Ninject
public ProductsController(IProductRepository _productsRepository)
{
this.productsRepository = _productsRepository;
}
public ViewResult List()
{
return View(productsRepository.Products.ToList());
}
}
I have modified the Web.config file to provide the db connection string and the Global.asax file Application_Start() method to include:
ControllerBuilder.Current.SetControllerFactory(new NinjectControllerFactory());
I am working on an example from the PRO ASP .NET MVC 2 book but just can't get this work, been trying all day.
If you just want out-out-the-box ninject functionality, you are doing too much by creating your own controller factory.
all you need is the following in global.asax
public class MvcApplication : NinjectHttpApplication
{
protected override IKernel CreateKernel()
{
var modules = new INinjectModule[]
{
new ServiceModule()
};
return new StandardKernel(modules);
}
protected override void OnApplicationStarted()
{
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
RegisterAllControllersIn(Assembly.GetExecutingAssembly());
}
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = "" } // Parameter defaults
);
}
internal class ServiceModule : NinjectModule
{
public override void Load()
{
// controllers
this.Bind<Controllers.AccountController>().ToSelf();
this.Bind<Controllers.HomeController>().ToSelf();
// Repository
Bind<Controllers.IFormsAuthentication>().To<Controllers.FormsAuthenticationService>();
Bind<Controllers.IMembershipService>().To<Controllers.AccountMembershipService>();
}
}
}

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