I trying create generic repository for ms sql db. Earlier i worked with something like this but with mongo db. I can compile project. but when i trying sent request i see error: "An error occurred when trying to create a controller of type 'EmployeeController'. Make sure that the controller has a parameterless public constructor." can anybody help me?
namespace TestTask.Util
{public class NinjectDependencyResolver
{
private IKernel kernel;
public NinjectDependencyResolver(IKernel kernelParam)
{
kernel = kernelParam;
AddBindings();
}
public object GetService(Type serviceType)
{
return kernel.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
return kernel.GetAll(serviceType);
}
private void AddBindings()
{
// repository
kernel.Bind<IEmployeeRepository>().To<EmployeeRepository>();
}
}
controller
namespace TestTask.Controllers
{
[RoutePrefix("api/v1")]
public class EmployeeController : ApiController
{
private readonly IEmployeeRepository _employeeRepository;
public EmployeeController(IEmployeeRepository employeeRepository) : base()
{
_employeeRepository = employeeRepository;
}
[HttpGet]
[Route("getItems")]
public IHttpActionResult GetItems(int take = 8, int skip = 0)
{
if(take<1|| skip < 0)
{
ModelState.AddModelError("Error", "Invalid take or skip params.");
return BadRequest(ModelState);
}
var result = _employeeRepository.Find(x => x.Id >= 0, x=>x.Id, take, skip);
return Ok(result);
}
[HttpGet]
[Route("pageCount")]
public IHttpActionResult PageCount(int itemsInPage)
{
var TotalCount = _employeeRepository.Count(x => x.Id >= 0);
var result = Math.Ceiling((double)TotalCount / (double)itemsInPage);
return Ok(result);
}
}
}
generic repository
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Linq.Expressions;
using System.Threading.Tasks;
using System.Web;
namespace TestTask.Context
{
public abstract class GenericRepository<TEntity> : IRepository<TEntity> where TEntity : class
{
private DefaultConnection context = new DefaultConnection();
public virtual List<TEntity> Find(Expression<Func<TEntity, bool>> predicate, Expression<Func<TEntity, object>> order, int take =50, int skip=0) //where TEntity : class
{
return context.Set<TEntity>().Where(predicate).OrderBy(order).Skip(skip).Take(take).ToList();
}
public virtual int Count(Expression<Func<TEntity, bool>> predicate)
{
return context.Set<TEntity>().Where(predicate).Count();
}
}
}
I had to do this a while back and remember it not being as straight forward with Web API as it is with MVC.
I posted details and a demo project as part of a unit of work example here, and github project here.
Below are the pieces for configuring dependency injection with Ninject.
UnitOfWorkExample.WebApi/Controllers/ProductsController.cs
namespace UnitOfWorkExample.WebApi.Controllers
{
[RoutePrefix("products")]
public class ProductsController : ApiController
{
private IProductService _productService;
public ProductsController(IProductService productService)
{
_productService = productService;
}
[Route]
public IHttpActionResult GetProducts()
{
// ensure there are products for the example
if (!_productService.GetAll().Any())
{
_productService.Create(new Product { Name = "Product 1" });
_productService.Create(new Product { Name = "Product 2" });
_productService.Create(new Product { Name = "Product 3" });
}
return Ok(_productService.GetAll());
}
}
}
UnitOfWorkExample.WebApi/App_Start/NinjectWebCommon.cs
namespace UnitOfWorkExample.WebApi.App_Start
{
using System;
using System.Web;
using Microsoft.Web.Infrastructure.DynamicModuleHelper;
using Ninject;
using Ninject.Web.Common;
using Ninject.Extensions.Conventions;
using System.Web.Http;
using UnitOfWorkExample.Domain.Helpers;
using UnitOfWorkExample.Data.Helpers;
public static class NinjectWebCommon
{
private static readonly Bootstrapper bootstrapper = new Bootstrapper();
/// <summary>
/// Starts the application
/// </summary>
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
}
/// <summary>
/// Stops the application.
/// </summary>
public static void Stop()
{
bootstrapper.ShutDown();
}
/// <summary>
/// Creates the kernel that will manage your application.
/// </summary>
/// <returns>The created kernel.</returns>
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
// Install our Ninject-based IDependencyResolver into the Web API config
GlobalConfiguration.Configuration.DependencyResolver = new NinjectResolver(kernel);
return kernel;
}
/// <summary>
/// Load your modules or register your services here!
/// </summary>
/// <param name="kernel">The kernel.</param>
private static void RegisterServices(IKernel kernel)
{
// unit of work per request
kernel.Bind<IUnitOfWork>().To<UnitOfWork>().InRequestScope();
// default binding for everything except unit of work
kernel.Bind(x => x.FromAssembliesMatching("*").SelectAllClasses().Excluding<UnitOfWork>().BindDefaultInterface());
}
}
}
UnitOfWorkExample.WebApi/App_Start/NinjectDependencyResolver.cs
namespace UnitOfWorkExample.WebApi.App_Start
{
public class NinjectScope : IDependencyScope
{
protected IResolutionRoot resolutionRoot;
public NinjectScope(IResolutionRoot kernel)
{
resolutionRoot = kernel;
}
public object GetService(Type serviceType)
{
IRequest request = resolutionRoot.CreateRequest(serviceType, null, new Parameter[0], true, true);
return resolutionRoot.Resolve(request).SingleOrDefault();
}
public IEnumerable<object> GetServices(Type serviceType)
{
IRequest request = resolutionRoot.CreateRequest(serviceType, null, new Parameter[0], true, true);
return resolutionRoot.Resolve(request).ToList();
}
public void Dispose()
{
IDisposable disposable = (IDisposable)resolutionRoot;
if (disposable != null) disposable.Dispose();
resolutionRoot = null;
}
}
public class NinjectResolver : NinjectScope, IDependencyResolver
{
private IKernel _kernel;
public NinjectResolver(IKernel kernel)
: base(kernel)
{
_kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectScope(_kernel.BeginBlock());
}
}
}
ASP.NET does not inject anything into controllers by default. Instead, it looks for a matching controller and just uses new. So it needs a controller that has a default constructor with no parameters-- unless you do something special to add DI.
To add dependency injection to your controllers, you need to register a custom controller factory. The factory should use Ninject to instantiate the controller, which will automatically populate its constructor arguments with the appropriate dependencies. Here is a bare bones example (you will need to modify it to allow other controller types, as well as implement the rest of the interface):
public class CustomControllerFactory : IControllerFactory
{
public IController CreateController(System.Web.Routing.RequestContext requestContext, string controllerName)
{
return _kernel.Get<EmployeeController>();
}
}
You can register it in startup with code like this:
protected void Application_Start()
{
IControllerFactory factory = new CustomControllerFactory();
ControllerBuilder.Current.SetControllerFactory(factory);
}
More info can be found here. The blogger shows you exactly the error that you are seeing and then fixes it.
Related
I'm trying to save my objects to my local database. We are using Microsoft Entity Framework and Ninject. Currently when I try to save my object I get the 'An entity object cannot be referenced by multiple instances of IEntityChangeTracker.' error. We are able to get data from the database currently, it is saving data that is causing problems.
The error is given the moment the savetickets function is called, Visual studio displays the error in the repository at context.Tickets.add(ticket). I have tried passing a single object instead of a list and saving that, this has however caused the same error.
We apply the same principle of creating repositories in other controllers as well for getting data from the database before we get to this part of the code where I'm trying to save tickets.
We have added a Ninject binding
kernel.Bind<ITicketRepository>().To<TicketRepository>();
Our EFDBContext looks like this
public class EFDbContext : DbContext
{
public DbSet<Ticket> Tickets { get; set; }
// Other Entities
public EFDbContext() : base("EFDbContext"){
}
}
The interface for the ticketrepository looks like this
public interface ITicketRepository
{
// Other functions
void SaveTickets(List<Ticket> tickets);
}
The repository implementing this interface looks like this
public class TicketRepository : ITicketRepository
{
private EFDbContext context = new EFDbContext();
// Other functions
public void SaveTickets(List<Ticket> tickets)
{
foreach (var item in tickets)
{
context.Tickets.Add(item);
}
context.SaveChanges();
}
}
The moment all of this is called is in my printtickets function. This is the only time the ticketrepository is created and called for in the code.
public class ReservationController : Controller
{
// Other repositories
private ITicketRepository ticketRepository;
public ReservationController(IMovieOverviewRepository movieRepository, IShowRepository showRepository, ITicketRepository ticketRepository)
{
// Other repositories
this.ticketRepository = ticketRepository;
}
// Other code
[HttpGet]
public ActionResult PrintTickets()
{
List<Ticket> tickets = (List<Ticket>)TempData["TicketList"];
ticketRepository.SaveTickets(tickets);
// Irrelevant stuff
}
}
EDIT: Our full ninject configuration. NinjectWebCommon.cs
public static class NinjectWebCommon
{
private static readonly Bootstrapper bootstrapper = new Bootstrapper();
/// <summary>
/// Starts the application
/// </summary>
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
}
/// <summary>
/// Stops the application.
/// </summary>
public static void Stop()
{
bootstrapper.ShutDown();
}
/// <summary>
/// Creates the kernel that will manage your application.
/// </summary>
/// <returns>The created kernel.</returns>
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
return kernel;
}
/// <summary>
/// Load your modules or register your services here!
/// </summary>
/// <param name="kernel">The kernel.</param>
private static void RegisterServices(IKernel kernel)
{
System.Web.Mvc.DependencyResolver.SetResolver(new Sprint123.WebUI.Infrastructure.NinjectDependencyResolver(kernel));
}
}
And NinjectDependencyResolver.cs
namespace Sprint123.WebUI.Infrastructure
{
public class NinjectDependencyResolver : IDependencyResolver
{
private IKernel kernel;
public NinjectDependencyResolver(IKernel kernelParam)
{
kernel = kernelParam;
AddBindings();
}
public object GetService(Type serviceType)
{
return kernel.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
return kernel.GetAll(serviceType);
}
private void AddBindings()
{
kernel.Bind<IShowRepository>().To<ShowRepository>();
kernel.Bind<ITicketRepository>().To<TicketRepository>();
kernel.Bind<IMovieOverviewRepository>().To<MovieOverviewRepository>();
}
}
}
Ok, after searching Google, here and several ASP/MVC forums I am bound to have to ask what the hell I am doing wrong here.
I have a good start to my application, an ok understanding of DI, IoC and am using the Repository, Service and UnitOfWork patterns. When I attempt to load a controller that needs the DI from Unity, it's as if unity is not resolving any of the registered items, or that I have done it poorly. From all the examples I can see for this version (not the version that creates the Bootstrap.cs file that is then called from Global.asax) I am doing what others have done with no love from Unity.
My core question is: Have I setup/configured Unity to inject the items into the controller constructor as needed or not. If I have, any ideas why it's not working like examples I have seen?
I keep getting the error that the AssetController needs to have a parameterless public constructor. If I add one, then it uses it without the DI and if I don't add one, then it yells about not having it.
Thanks, code below.
UnityConfig.cs
namespace CARS.web.App_Start
{
/// <summary>
/// Specifies the Unity configuration for the main container.
/// </summary>
public class UnityConfig
{
#region Unity Container
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
/// <summary>
/// Gets the configured Unity container.
/// </summary>
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
#endregion
/// <summary>Registers the type mappings with the Unity container.</summary>
/// <param name="container">The unity container to configure.</param>
/// <remarks>There is no need to register concrete types such as controllers or API controllers (unless you want to
/// change the defaults), as Unity allows resolving a concrete type even if it was not previously registered.</remarks>
public static void RegisterTypes(IUnityContainer container)
{
// NOTE: To load from web.config uncomment the line below. Make sure to add a Microsoft.Practices.Unity.Configuration to the using statements.
// container.LoadConfiguration();
// TODO: Register your types here
// container.RegisterType<IProductRepository, ProductRepository>();
container.RegisterType<IDataContext, CARSDEMOContext>(new PerRequestLifetimeManager())
.RegisterType<IAssetService, AssetService>()
.RegisterType<IUnitOfWork, UnitOfWork>()
.RegisterType<IRepository<Asset>, Repository<Asset>>();
//.RegisterType<AssetController>(new InjectionConstructor(typeof(IAssetService), typeof(IUnitOfWork)));
}
}
}
AssetController.cs (constructor portion where I am doing the injection params)
namespace CARS.web.Controllers
{
public class AssetController : Controller
{
private readonly IAssetService _assetService;
private readonly IUnitOfWork _unitOfWork;
public AssetController(IAssetService assetService, IUnitOfWork unitOfWork)
{
_assetService = assetService;
_unitOfWork = unitOfWork;
}
//other methods for CRUD etc stripped for brevity
}
}
IAssetService.cs (first param is the assetService )
namespace CARS.service
{
public interface IAssetService : IService<Asset>
{
Task<IEnumerable<Asset>> GetAsync();
Task<Asset> FindAsync(Guid id);
Asset Add(Asset asset);
Asset Update(Asset asset);
void Remove(Guid id);
}
}
AssetService.cs (concrete implementation for IAssetService interaction)
namespace CARS.service
{
public class AssetService : Service<Asset>, IAssetService
{
private readonly IRepositoryAsync<Asset> _repository;
public AssetService(IRepositoryAsync<Asset> repository) : base(repository)
{
_repository = repository;
}
public Task<IEnumerable<Asset>> GetAsync()
{
//return _repository.Query().SelectAsync();
return _repository.Query().SelectAsync();
}
public Task<Asset> FindAsync(Guid id)
{
return _repository.FindAsync(id);
}
public Asset Add(Asset asset)
{
_repository.Insert(asset);
return asset;
}
public Asset Update(Asset asset)
{
_repository.Update(asset);
return asset;
}
public void Remove(Guid id)
{
_repository.Delete(id);
}
}
}
IUnitOfWork.cs (this is from Long Le's Generic UofW and Repository - http://genericunitofworkandrepositories.codeplex.com/)
namespace Repository.Pattern.UnitOfWork
{
public interface IUnitOfWork : IDisposable
{
int SaveChanges();
Task<int> SaveChangesAsync();
void Dispose(bool disposing);
IRepository<TEntity> Repository<TEntity>() where TEntity : IObjectState;
void BeginTransaction();
bool Commit();
void Rollback();
}
}
UnitOfWork.cs (again from Long Le's framework)
namespace Repository.Pattern.Ef6
{
public class UnitOfWork : IUnitOfWork, IUnitOfWorkAsync
{
#region Private Fields
private readonly IDataContextAsync _dataContext;
private bool _disposed;
private ObjectContext _objectContext;
private Dictionary<string, object> _repositories;
private DbTransaction _transaction;
#endregion Private Fields
#region Constuctor/Dispose
public UnitOfWork(IDataContextAsync dataContext)
{
_dataContext = dataContext;
}
public void Dispose()
{
if (_objectContext != null && _objectContext.Connection.State == ConnectionState.Open)
_objectContext.Connection.Close();
Dispose(true);
GC.SuppressFinalize(this);
}
public virtual void Dispose(bool disposing)
{
if (!_disposed && disposing)
_dataContext.Dispose();
_disposed = true;
}
#endregion Constuctor/Dispose
public int SaveChanges()
{
return _dataContext.SaveChanges();
}
public IRepository<TEntity> Repository<TEntity>() where TEntity : IObjectState
{
return RepositoryAsync<TEntity>();
}
public Task<int> SaveChangesAsync()
{
return _dataContext.SaveChangesAsync();
}
public Task<int> SaveChangesAsync(CancellationToken cancellationToken)
{
return _dataContext.SaveChangesAsync(cancellationToken);
}
public IRepositoryAsync<TEntity> RepositoryAsync<TEntity>() where TEntity : IObjectState
{
if (_repositories == null)
_repositories = new Dictionary<string, object>();
var type = typeof (TEntity).Name;
if (_repositories.ContainsKey(type))
return (IRepositoryAsync<TEntity>) _repositories[type];
var repositoryType = typeof (Repository<>);
_repositories.Add(type, Activator.CreateInstance(repositoryType.MakeGenericType(typeof (TEntity)), _dataContext, this));
return (IRepositoryAsync<TEntity>) _repositories[type];
}
#region Unit of Work Transactions
public void BeginTransaction()
{
_objectContext = ((IObjectContextAdapter) _dataContext).ObjectContext;
if (_objectContext.Connection.State != ConnectionState.Open)
{
_objectContext.Connection.Open();
_transaction = _objectContext.Connection.BeginTransaction();
}
}
public bool Commit()
{
_transaction.Commit();
return true;
}
public void Rollback()
{
_transaction.Rollback();
((DataContext)_dataContext).SyncObjectsStatePostCommit();
}
#endregion
// Uncomment, if rather have IRepositoryAsync<TEntity> IoC vs. Reflection Activation
//public IRepositoryAsync<TEntity> RepositoryAsync<TEntity>() where TEntity : EntityBase
//{
// return ServiceLocator.Current.GetInstance<IRepositoryAsync<TEntity>>();
//}
}
}
Updated to include the SetResolver info from UnityMvcActivator.cs
using System.Linq;
using System.Web.Mvc;
using Microsoft.Practices.Unity.Mvc;
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(CARS.web.App_Start.UnityWebActivator), "Start")]
namespace CARS.web.App_Start
{
/// <summary>Provides the bootstrapping for integrating Unity with ASP.NET MVC.</summary>
public static class UnityWebActivator
{
/// <summary>Integrates Unity when the application starts.</summary>
public static void Start()
{
var container = UnityConfig.GetConfiguredContainer();
FilterProviders.Providers.Remove(FilterProviders.Providers.OfType<FilterAttributeFilterProvider>().First());
FilterProviders.Providers.Add(new UnityFilterAttributeFilterProvider(container));
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
// TODO: Uncomment if you want to use PerRequestLifetimeManager
Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility.RegisterModule(typeof(UnityPerRequestHttpModule));
}
}
}
I have read/tried the following info/data and nothing has fixed it:
The type IUserStore`1 does not have an accessible constructor
How to add MVC 5 authentication to Unity IoC?
Types not resolving with Unity [MVC 5]
I have ready where one must write a ControllerFactory for Unity to be able to do this, but that seems quite a bit of work when all the examples I have found simply have the config registered, and the injection apparently happening on the controllers and other classes as need.
And finally the error:
The following server error was encountered:
An error occurred when trying to create a controller of type 'CARS.web.Controllers.AssetController'. Make sure that the controller has a parameterless public constructor.Details are:
at System.Web.Mvc.DefaultControllerFactory.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) at System.Web.Mvc.DefaultControllerFactory.CreateController(RequestContext requestContext, String controllerName) at System.Web.Mvc.MvcHandler.ProcessRequestInit(HttpContextBase httpContext, IController& controller, IControllerFactory& factory) at System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionSte p.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
Thanks
You need to set the DependencyResolver. I cant see the code in the example you provided where this is done.
Once setting up your UnityContainer and registering your types, you need to set the System.Web.MVC.DependencyResolver.
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
You may have missed (like I did) to register the async types in UnityConfig.cs
Check if you have this:
container.RegisterType<IUnitOfWork, UnitOfWork>(new PerRequestLifetimeManager())
.RegisterType<IUnitOfWorkAsync, UnitOfWork>(new PerRequestLifetimeManager())
.RegisterType<IDataContextAsync, SomeDBContext>(new PerRequestLifetimeManager())
.RegisterType<IDataContext, SomeDBContext>(new PerRequestLifetimeManager())
.RegisterType<ISomeService, SomeService>(new PerRequestLifetimeManager())
.RegisterType<IRepositoryAsync<Some>, Repository<Some>>(new PerRequestLifetimeManager());
1:
Uncomment in file UnityMvcActivator this line:
Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility.RegisterModule(typeof(UnityPerRequestHttpModule));
2:
Basic registration with Unity + UnitOfwork + Repository
this must exists in file: UnityConfig:
container.RegisterType<IDataContextAsync, KlussendirectContext>(new PerRequestLifetimeManager());
container.RegisterType<IDataContext, KlussendirectContext>(new PerRequestLifetimeManager());
container.RegisterType<IUnitOfWork, UnitOfWork>(new PerRequestLifetimeManager());
container.RegisterType<IUnitOfWorkAsync, UnitOfWork>(new PerRequestLifetimeManager());
3:
When you use Dependency Injection in a controller(api) then a parameter less constructor should exists:
e.g.
public MyNameController() : base(){}
If followed those steps, it should work (Edit, Insert, Delete, etc..)
I am using Ninject together with ASP.NET MVC 4. I am using repositories and want to do constructor injection to pass in the repository to one of the controllers.
Here is my context object (EntityFramework) that implements my StatTracker interface:
public class StatTrackerRepository : IStatTrackerRepository
{
private GolfStatTrackerEntities _ctx;
public StatTrackerRepository(GolfStatTrackerEntities ctx)
{
_ctx = ctx;
}
public IQueryable<Facility> GetFacilites()
{
return _ctx.Facilities;
}
}
This is my Repository interface:
public interface IStatTrackerRepository
{
IQueryable<Facility> GetFacilites();
}
Which then calls my Home Controller:
public class HomeController : Controller
{
public IStatTrackerRepository _repo { get; set; }
public HomeController(IStatTrackerRepository repo)
{
_repo = repo;
}
public ActionResult Index()
{
var facilities = _repo.GetFacilites().ToList();
return View(facilities);
}
}
The page loads properly, however, once the page is loaded, it immedately uses an angularjs Controller which calls the $http method:
function facilityIndexController($scope, $http) {
$scope.data = [];
$http({ method: 'GET', url: '/api/facility' }).
success(function(result) {
angular.copy(result.data, $scope.data);
}).error(function() {
alert("Could not load facilities");
});
}
...which calls the following API controller:
public class FacilityController : ApiController
{
public IStatTrackerRepository _repo { get; set; }
public GolfStatTrackerEntities ctx { get; set; }
//public FacilityController()
//{
// _repo = new StatTrackerRepository(ctx);
//}
public FacilityController(IStatTrackerRepository repo)
{
_repo = repo;
}
public IEnumerable<Facility> Get()
{
var facilities = _repo.GetFacilites().ToList();
return facilities;
}
}
....where it falls into the error function of the angular $http call because the FacilityController(IStatTrackerRepository repo) is never ran.
I have tried using a parameterless contstructor that instantiates a StatTrackerRepository(ctx) for FacilityController(), however, I get a NullReferenceException when I do so.
My Ninject config is as follows:
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
try
{
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
//GlobalConfiguration.Configuration.DependencyResolver =
// new NinjectResolver(kernel);
return kernel;
}
catch
{
kernel.Dispose();
throw;
}
}
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<GolfStatTrackerEntities>().To<GolfStatTrackerEntities>().InRequestScope();
kernel.Bind<IStatTrackerRepository>().To<StatTrackerRepository>().InRequestScope();
}
I'm not sure if this is something wrong with Ninject or if there is an issue with how I am implementing Ninject. The injection seems to be working on the initial load of the Home view, however, when it uses angular to call the API, there is a disconnect with Ninject.
Please help.
We ended up using a similar configuration on one of our older projects and realized that we needed to add a little more infrastructure code to our MVC/WebApi App:
NinjectDependencyScope.cs
using System;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using System.Web.Http.Dependencies;
using Ninject;
using Ninject.Syntax;
namespace YourAppNameSpace
{
public class NinjectDependencyScope : IDependencyScope
{
private IResolutionRoot _resolver;
internal NinjectDependencyScope(IResolutionRoot resolver)
{
Contract.Assert(resolver != null);
_resolver = resolver;
}
public void Dispose()
{
var disposable = _resolver as IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
_resolver = null;
}
public object GetService(Type serviceType)
{
if (_resolver == null)
{
throw new ObjectDisposedException("this", "This scope has already been disposed");
}
return _resolver.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
if (_resolver == null)
{
throw new ObjectDisposedException("this", "This scope has already been disposed");
}
return _resolver.GetAll(serviceType);
}
}
}
NinjectDependencyResolver.cs
using System.Web.Http.Dependencies;
using Ninject;
namespace YourAppNameSpace
{
public class NinjectDependencyResolver : NinjectDependencyScope, IDependencyResolver
{
private readonly IKernel _kernel;
public NinjectDependencyResolver(IKernel kernel)
: base(kernel)
{
_kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectDependencyScope(_kernel.BeginBlock());
}
}
}
Then we added the following to the NinjectWebCommon.cs file:
public static void RegisterNinject(HttpConfiguration configuration)
{
// Set Web API Resolver
configuration.DependencyResolver = new NinjectDependencyResolver(Bootstrapper.Kernel);
}
And then the following to Global.asax.cs file, Application_Start method:
NinjectWebCommon.RegisterNinject(GlobalConfiguration.Configuration);
This is my controller
public class SuggestionController : ApiController
{
public ISuggestionRepository Repository { get; private set; }
public SuggestionController(ISuggestionRepository repository)
{
this.Repository = repository;
}
// to post suggestion
[HttpPost]
[ActionName("PostSuggestion")]
public HttpResponseMessage PostSuggestion(Suggestion suggestion)
{
var answerCorrect = this.Repository.CreateSuggestion(suggestion);
if (answerCorrect == true)
return Request.CreateResponse(HttpStatusCode.OK);
else
return Request.CreateResponse(HttpStatusCode.Conflict);
}
}
and this is my RegisterServices method in NinjectWebCommon.cs
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<ICompetitionRepository>().To(typeof(CompetitionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Competition>());
kernel.Bind<ISubmissionRepository>().To(typeof(SubmissionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Submission>());
kernel.Bind<IUserRepository>().To(typeof(UserRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<User>());
kernel.Bind<ISuggestionRepository>().To(typeof(SuggestionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Suggestion>());
}
But am getting an exception that my suggestion controller does not have a default constructor and its showing a 500 internal server when am hitting the controller from a client app
I know that we get the exception of controller not having default constructor if the ninject dependency is not working properly but the below is another controller i have implemeneted similar to suggestion controller and its working absolutely fine.
public IUserRepository Repository { get; private set; }
public SSOController(IUserRepository repository)
{
this.Repository = repository;
}
[HttpPost]
[ActionName("PostUser")]
public HttpResponseMessage PostUser([FromBody]string id)
{
var accessToken = id;
var client = new FacebookClient(accessToken);
dynamic result = client.Get("me", new { fields = "name,email" });
string name = result.name;
string email = result.email;
var existingUser = this.Repository.FindByUserIdentity(name);
if (existingUser == null)
{
var newUser = new User
{
Username = name,
Email = email,
};
var success = this.Repository.CreateAccount(newUser);
if (!success)
{
return Request.CreateResponse(HttpStatusCode.InternalServerError);
}
//return created status code as we created the user
return Request.CreateResponse<User>(HttpStatusCode.Created, newUser);
}
return Request.CreateResponse(HttpStatusCode.OK);
}
}
I have no idea where am going wrong. Please let me know if u have any suggestions.
EDIT:
my Global.asax
public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
WebApiConfig.Register(GlobalConfiguration.Configuration);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
AuthConfig.RegisterAuth();
GlobalConfiguration.Configuration.IncludeErrorDetailPolicy =
IncludeErrorDetailPolicy.Always;
}
Dependency resolver am using
// Provides a Ninject implementation of IDependencyScope
// which resolves services using the Ninject container.
public class NinjectDependencyScope : IDependencyScope
{
IResolutionRoot resolver;
public NinjectDependencyScope(IResolutionRoot resolver)
{
this.resolver = resolver;
}
public object GetService(Type serviceType)
{
if (resolver == null)
throw new ObjectDisposedException("this", "This scope has been disposed");
return resolver.TryGet(serviceType);
}
public System.Collections.Generic.IEnumerable<object> GetServices(Type serviceType)
{
if (resolver == null)
throw new ObjectDisposedException("this", "This scope has been disposed");
return resolver.GetAll(serviceType);
}
public void Dispose()
{
IDisposable disposable = resolver as IDisposable;
if (disposable != null)
disposable.Dispose();
resolver = null;
}
}
// This class is the resolver, but it is also the global scope
// so we derive from NinjectScope.
public class NinjectDependencyResolver : NinjectDependencyScope, IDependencyResolver
{
IKernel kernel;
public NinjectDependencyResolver(IKernel kernel)
: base(kernel)
{
this.kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectDependencyScope(kernel.BeginBlock());
}
}
and calling it in CreateKernel() method in NinjectWebCommon
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
// Install our Ninject-based IDependencyResolver into the Web API config
GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(kernel);
return kernel;
}
Suggestion Repository
public class SuggestionRepository : Repository<Suggestion>, ISuggestionRepository
{
public SuggestionRepository(IServiceContext<Suggestion> servicecontext)
: base(servicecontext)
{ }
public bool CreateSuggestion(Suggestion suggestion)
{
this.ServiceContext.Create(suggestion);
this.ServiceContext.Save();
return true;
}
}
ISuggestionRepository
public interface ISuggestionRepository
{
bool CreateSuggestion(Suggestion suggestion);
}
Repository
public abstract class Repository<T>
{
public IServiceContext<T> ServiceContext { get; private set; }
public Repository(IServiceContext<T> serviceContext)
{
this.ServiceContext = serviceContext;
}
}
IserviceContext
public interface IServiceContext<T>
{
IQueryable<T> QueryableEntities { get; }
void Create(T entity);
void Update(T entity);
void Delete(T entity);
void Save();
}
Since you're using WebApi, you will need to use the WebApi extension for Ninject. Unfortunately, the current Ninject.WebApi nuget package is out of date, and doesn't work with the released version of WebApi.
Temporarily, until Remo gets around to updating Ninject.WebApi to the release version, you can use Ninject.WebApi-RC http://nuget.org/packages/Ninject.Web.WebApi-RC
http://www.eyecatch.no/blog/2012/06/using-ninject-with-webapi-rc/
EDIT:
To recap the information discussed in comments, Here are the recommendations:
1) Use Ninject.MVC3 and Ninject.Web.WebApi (but use Ninject.Web.WebApi-RC until the official is updated) as discussed above. Do not use a custom DependencyResolver, and let Ninject.Web.Mvc and .WebApi do their job.
2) Change your bindings to this:
kernel.Bind<ICompetitionRepository>().To<CompetitionRepository>();
... similar bindings
3) Add a generic binding for your ServiceContext
kernel.Bind(typeof(IServiceContext<>)).To(typeof(InMemoryDataContext<>));
I think the problem is you're using the ApiController.
Controllers and apiControllers are using a different dependancy injection container.
Both of them however expose the same methods.
If the working controller is inheriting the Controller class then that's your cause.
For a work around take a look at
this topic
I have faced the same issue.
This is how I rectified:
I created a WebContainerManager which is just a static wrapper around container.
Static container wrappers useful when you don't control instantiation and can't rely on injection - e.g. action filter attributes
public static class WebContainerManager
{
public static IKernel GetContainer()
{
var resolver = GlobalConfiguration.Configuration.DependencyResolver as NinjectDependencyResolver;
if (resolver != null)
{
return resolver.Container;
}
throw new InvalidOperationException("NinjectDependencyResolver not being used as the MVC dependency resolver");
}
public static T Get<T>()
{
return GetContainer().Get<T>();
}
}
Inside your controller, call your empty constructor like this with no parameters:
public SuggestionController() : this(WebContainerManager.Get<ISuggestionRepository>())
{
}
This should work.
This technique i got from the book on MVC4 by Jamie Kurtz #jakurtz.
You probably need to do some dependency injection so you can inject the ISuggestionRepository parameter on your SuggestionController constructor. To do that you need to override methods in the DefaultControllerFactory class to customize the creation of controllers. Since you are using NInject, you can have something like:
public class NInjectControllerFactory : DefaultControllerFactory
{
private IKernel kernel = new StandardKernel(new CustomModule());
protected override IController GetControllerInstance(System.Web.Routing.RequestContext requestContext, Type controllerType)
{
return controllerType == null ? null : (IController)kernel.Get(controllerType);
}
public class CustomModule : NinjectModule
{
public override void Load()
{
this.Bind<ICompetitionRepository>().To(typeof(CompetitionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Competition>());
this.Bind<ISubmissionRepository>().To(typeof(SubmissionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Submission>());
this.Bind<IUserRepository>().To(typeof(UserRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<User>());
this.Bind<ISuggestionRepository>().To(typeof(SuggestionRepository))
.WithConstructorArgument("serviceContext", new InMemoryDataContext<Suggestion>());
}
}
}
Then in your Global.asax.cs, you can add a line to swap out the controller factory
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
ControllerBuilder.Current.SetControllerFactory(new NInjectControllerFactory());
}
I am using the ninject mvc3 plugin with my web api application. I have a binding that looks like:
kernel.Bind<IFoo>().To<Foo>().InSingletonScope();
It is my interpretation that the kernal will create exactly one instance of Foo and reuse it appropriately. By putting a breakpoint in Foo's constructor, I can clearly see that it is getting called once per request, and I cannot explain why.
My only guess is that somehow a new kernel is getting created per request, but that doesn't appear to be the case, as the CreateKernel method which sets the global dependency resolver is only getting run once in the application lifetime.
I am using some code taken from this post to make ninject play nice with mvc 4. Because of framework changes, I had to make an additional wrapper that I assign to GlobalConfiguration.Configuration.DependencyResolver:
public class NinjectResolver : NinjectScope, IDependencyResolver
{
private readonly IKernel _kernel;
public NinjectResolver(IKernel kernel)
: base(kernel)
{
_kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectScope(_kernel.BeginBlock());
}
}
What am I doing wrong?
I never could get it to work properly, and I am not sure why. My guess is it has something to do with MVC4 integration being a bit immature at the moment.
As an alternative I am using:
kernel.Bind<IFoo>().ToConstant(new Foo());
This seems to work, but I am not too happy with it.
Like previously mentioned it does look like a bug.
One option is to simply implement a singleton extension method yourself:
public static class NinjectSingletonExtension
{
public static CustomSingletonKernelModel<T> SingletonBind<T>(this IKernel i_KernelInstance)
{
return new CustomSingletonKernelModel<T>(i_KernelInstance);
}
}
public class CustomSingletonKernelModel<T>
{
private const string k_ConstantInjectionName = "Implementation";
private readonly IKernel _kernel;
private static object padlock = new Object();
private T _concreteInstance;
public CustomSingletonKernelModel(IKernel i_KernelInstance)
{
this._kernel = i_KernelInstance;
}
public IBindingInNamedWithOrOnSyntax<T> To<TImplement>(TImplement i_Constant = null) where TImplement : class, T
{
_kernel.Bind<T>().To<TImplement>().Named(k_ConstantInjectionName);
var toReturn =
_kernel.Bind<T>().ToMethod(x =>
{
if (i_Constant != null)
{
return i_Constant;
}
if (_concreteInstance == null)
{
lock (padlock)
{
if (_concreteInstance == null)
{
_concreteInstance = _kernel.Get<T>(k_ConstantInjectionName);
}
}
}
return _concreteInstance;
}).When(x => true);
return toReturn;
}
}
And then simply use:
i_Kernel.SingletonBind<T>().To<TImplement>();
Rather then
i_Kernel.Bind<T>().To<TImplement>().InSingletonScope();
Certainly arriving late to this thread but it just happened to me with a Windows Service hosting OWIN for Web API controllers and resolving dependencies with Ninject, InSingletonScope() wasn't working until I did the following:
var kernel = new StandardKernel();
...
kernel.Bind<Foo>().ToSelf().InSingletonScope();
kernel.Bind<IFoo>().ToMethod(context => context.Kernel.Get<Foo>());
...
// Controllers ask for the dependency as usual...
public class SomeController : ApiController
{
readonly IFoo _foo;
public SomeController(IFoo foo)
{
_foo = foo;
}
...
Hope this helps
Note: I used nuget to install ninject & ninject.web.mvc (which I'm sure you did as well).
I'm not able to see the rest of your code, but here's what I had in my "NinjectDependencyScope" class. (I think yours is just called NinjectScope, might be some other naming inconsistencies with your code)
public class NinjectDependencyScope : IDependencyScope
{
private IResolutionRoot _resolver;
internal NinjectDependencyScope(IResolutionRoot resolver)
{
Contract.Assert(resolver != null);
_resolver = resolver;
}
#region IDependencyScope Members
public void Dispose()
{
var disposable = _resolver as IDisposable;
if (disposable != null)
disposable.Dispose();
_resolver = null;
}
public object GetService(Type serviceType)
{
if (_resolver == null)
throw new ObjectDisposedException("this", "This scope has already been disposed");
return _resolver.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
if (_resolver == null)
throw new ObjectDisposedException("this", "This scope has already been disposed");
return _resolver.GetAll(serviceType);
}
#endregion
}
And here is my NinjectWebCommon class (located in App_Start folder):
using System;
using System.Web;
using System.Web.Http;
using Microsoft.Web.Infrastructure.DynamicModuleHelper;
using Ninject;
using Ninject.Modules;
using Ninject.Web.Common;
[assembly: WebActivator.PreApplicationStartMethod(typeof(ABCD.Project.Web.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(ABCD.Project.Web.App_Start.NinjectWebCommon), "Stop")]
namespace ABCD.Project.Web.App_Start
{
public static class NinjectWebCommon
{
private static readonly Bootstrapper Bootstrap = new Bootstrapper();
/// <summary>
/// Starts the application
/// </summary>
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
Bootstrap.Initialize(CreateKernel);
}
/// <summary>
/// Stops the application.
/// </summary>
public static void Stop()
{
Bootstrap.ShutDown();
}
/// <summary>
/// Creates the kernel that will manage your application.
/// </summary>
/// <returns>The created kernel.</returns>
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
// Set Web API Resolver
GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(kernel);
return kernel;
}
/// <summary>
/// Load your modules or register your services here!
/// </summary>
/// <param name="kernel">The kernel.</param>
private static void RegisterServices(IKernel kernel)
{
//var modules = new INinjectModule[] { new NinjectBindingModule(), };
//kernel.Load(modules);
Here's where you would load your modules or define your bindings manually...
}
}
}