ASP.Net MVC 3 Unit of Work Disposal - asp.net-mvc-3

I am writing an ASP.Net MVC 3 Web Application using Entity Framework 4.1. My Unit of Work class is the same as described in this excellent tutorial http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/implementing-the-repository-and-unit-of-work-patterns-in-an-asp-net-mvc-application
However, instead of injecting my UoW class into my Controller, I do so in my Service Class, like so
public class ListService : IListService
{
private IUnitOfWork _uow;
public ListService(IUnitOfWork uow)
{
_uow = uow;
}
public IList<List> GetAllListTypes()
{
return _uow.Lists.Get().OrderBy(l => l.description).ToList();
}
}
My Unit of Work class is like this
public class UnitOfWork : IUnitOfWork, IDisposable
{
readonly LocumEntities _context = new LocumEntities();
private GenericRepository<List> _lists = null;
public IGenericRepository<List> Lists
{
get
{
if (_lists == null)
{
_lists = new GenericRepository<List>(_context);
}
return _lists;
}
}
public void Commit()
{
_context.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
_context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
And this all works fine. However, you'll notice I have methods in my UoW class to dispose of the DbContext. I wish to dispose of the UoW class after every business transaction like is done in the above mentioned tutorial, they do this by using the following code in their controller
protected override void Dispose(bool disposing)
{
db.Dispose();
base.Dispose(disposing);
}
I tried to amend this method and place it in my service class however it does not work, ie, the dispose method in the UoW class never gets called
protected override void Dispose(bool disposing)
{
_uow.Dispose();
}
I would greatly appreciate if someone could point me in the correct direction with how to dispose of my UoW class.
Thank you.

Folks
The answer to this is, as I am using Unity for my IoC, it can be setup to take care of disposing of my Unit of Work class.

Related

Confused about using dispose in my repository. EF6 MVC

I have been trying to implement a repository pattern in my project. I am not sure if i am using dispose correctly. I took the pattern from the MVA course on entity framework.
My repository
public static bool IsAwesome { get { return true; } }
public class Repository<T> : IDisposable where T : class
{
private ApplicationDbContext db = null;
protected DbSet<T> DbSet { get; set; }
public Repository()
{
db = new ApplicationDbContext();
DbSet = db.Set<T>();
}
public List<T> GetAll()
{
return DbSet.ToList();
}
public T Get(int id)
{
return DbSet.Find(id);
}
public T GetWithString(string id)
{
return DbSet.Find(id);
}
public void Add(T entity)
{
DbSet.Add(entity);
}
public void Update(T entity)
{
DbSet.Attach(entity);
db.Entry(entity);
}
public void SaveChanges()
{
db.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
db.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
Example of imageRepository which inherits from repository
public class ImageRepository : Repository<Image>
{
public Image GetLatest(int vehicleId)
{
return DbSet.FirstOrDefault(p => p.VehicleId == vehicleId);
}
public List<Image> GetImagesByVehicleId(int vehicleId)
{
return DbSet.Where(p => p.VehicleId == vehicleId).ToList();
}
}
Using my repository on top of the controller and disposing in the bottom of my controller
ImageRepository imageRepository = new ImageRepository();
UserRepository userRepository = new UserRepository();
protected override void Dispose(bool disposing)
{
imageRepository.Dispose();
userRepository.Dispose();
base.Dispose(disposing);
}
Will my code handle all unmanaged connections and close them correctly?
Thank you in advance. Im still a bit new to MVC and EF. I am sorry if my question is a bit newbish. My first post in here. So i hope i did not break any rules:)
Add your Dispose code in UnitOfWork,Remove From GenericRepository
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
Context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
Will my code handle all unmanaged connections and close them
correctly?
Apparently yes.
However, you are not quite following the pattern. You don't have to SuppressFinalize as you don't have a finalizer in your class.Have a read about proper implementation of IDisposable Pattern.

Ninject Interception in WebAPI and parameterless constructor failing

I have an MVC4 site that uses both MVC and WebAPI in it. All was going well till I tried to change my classes to have a cross cutting AOP class that would help with caching data. I am now finding that when I call a method that does not have the InterceptAttribute on it, it will crash because Ninject didn't inject with a parameter, and it fails.
My BLL class looks like this:
public class FooBLL
{
#region Private Variables
private readonly IDAL _context;
#endregion
#region Constructor
public Foo(IDAL context)
{
_context = context;
}
#endregion
#region Public Methods
public List<Bar> GetAllBars()
{
return _context.GetAllBars();
}
public List<Bar> GetTwoBars()
{
return _context.GetTwoBars();
}
#endregion
}
My WebApi Controller looks like this:
public class FooController : ApiController
{
#region Private Variables
private readonly FooBLL _fooBll;
#endregion
#region Constructor
public FooController(FooBLL fooBll)
{
_fooBll = fooBll;
}
#endregion
#region Public Methods
#region Estimate Types
#region Get
public List<Bar> GetAllBars()
{
return _fooBll.GetAllBars();
}
public List<Bar> GetTwoBars()
{
return _fooBll.GetTwoBars();
}
#endregion
#endregion
#endregion
}
In my Website, I created the following Ninject classes for resolving the controllers:
public class NinjectRegistrations : NinjectModule
{
public override void Load()
{
Kernel.Bind<IDAL>().To<DAL>().InSingletonScope();
}
}
public class NinjectDependencyResolver : NinjectDependencyScope, IDependencyResolver, System.Web.Mvc.IDependencyResolver
{
private readonly IKernel kernel;
public NinjectDependencyResolver(IKernel kernel)
: base(kernel)
{
this.kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectDependencyScope(this.kernel.BeginBlock());
}
}
public class NinjectDependencyScope : IDependencyScope
{
private IResolutionRoot resolver;
internal NinjectDependencyScope(IResolutionRoot resolver)
{
Contract.Assert(resolver != null);
this.resolver = resolver;
}
public void Dispose()
{
var disposable = this.resolver as IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
this.resolver = null;
}
public object GetService(Type serviceType)
{
if (this.resolver == null)
{
throw new ObjectDisposedException("this", "This scope has already been disposed");
}
return this.resolver.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
if (this.resolver == null)
{
throw new ObjectDisposedException("this", "This scope has already been disposed");
}
return this.resolver.GetAll(serviceType);
}
}
In Global.asax I then register this resolver:
NinjectHelper.Kernel = new StandardKernel(modules);
var ninjectResolver = new NinjectDependencyResolver(NinjectHelper.Kernel);
DependencyResolver.SetResolver(ninjectResolver); // MVC
GlobalConfiguration.Configuration.DependencyResolver = ninjectResolver; // Web API
//Register Filter Injector
GlobalConfiguration.Configuration.Services.Add(typeof(System.Web.Http.Filters.IFilterProvider), new NinjectWebApiFilterProvider(NinjectHelper.Kernel));
Things were fine till I added the attribute Cache using Ninject.Extensions.Interception.Attributes.InterceptAttribute.
The class now looks like this (note that I added a parameterless constructor and marked one of the methods as virtual, these are both required for the Interception to work):
public class FooBLL
{
#region Private Variables
private readonly IDAL _context;
#endregion
#region Constructor
public Foo(IDAL context)
{
_context = context;
}
public Foo()
{
}
#endregion
#region Public Methods
public List<Bar> GetAllBars()
{
return _context.GetAllBars();
}
[Cache(DefaultTimeoutMinutes = 20)]
public virtual List<Bar> GetTwoBars()
{
return _context.GetTwoBars();
}
#endregion
}
Now on the WebAPI controller, when I call GetToBars(the method with the Intercept Attribute), everything still works fine.
However, when I call GetAllBars(the method that doesn't have the Intercept Attribute), I fail with an exception that _context is null.
Any help would be greatly appreciated.
Ben

"The type IUnitOfWork does not have an accessible constructor" with Umbraco 6.1, UmbracoApiController (Web API) & Dependency Injection (Unity)

I am using Umbraco 6.1 with an UmbracoApiController which has a IUnitOfWork injected into it's constructor. To inject the dependencies, I am using Unity, like I have in the past with standard Web API projects. Normally, I set unity up in the Global.asax.cs. As Umbraco does not have this I have created my own UmbracoEvents handler, which inherits from IApplicationEventHandler, and has the methods:
OnApplicationInitialized
OnApplicationStarting
OnApplicationStarted
ConfigureApi
In the OnApplicationStarted method I set up my EF database, db initializer etc and call ConfigureApi to set up Unity. My OnApplication Started and ConfigureApi methods looks like this:
public void OnApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
{
_applicationContext = applicationContext;
_umbracoApplication = umbracoApplication;
_contentService = ApplicationContext.Current.Services.ContentService;
this.ConfigureApi(GlobalConfiguration.Configuration);
Database.SetInitializer(null);
PropertySearchContext db = new PropertySearchContext();
db.Database.Initialize(true);
}
private void ConfigureApi(HttpConfiguration config)
{
var unity = new UnityContainer();
unity.RegisterType<PropertiesApiController>();
unity.RegisterType<IUnitOfWork, UnitOfWork>(new HierarchicalLifetimeManager());
config.DependencyResolver = new IoCContainer(unity);
}
My Controller code:
public class PropertiesApiController : UmbracoApiController
{
private readonly IUnitOfWork _unitOfWork;
public PropertiesApiController(IUnitOfWork unitOfWork)
{
if(null == unitOfWork)
throw new ArgumentNullException();
_unitOfWork = unitOfWork;
}
public IEnumerable GetAllProperties()
{
return new[] {"Table", "Chair", "Desk", "Computer", "Beer fridge"};
}
}
My Scope Container/IoC Container code: (as per http://www.asp.net/web-api/overview/extensibility/using-the-web-api-dependency-resolver)
public class ScopeContainer : IDependencyScope
{
protected IUnityContainer container;
public ScopeContainer(IUnityContainer container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
this.container = container;
}
public object GetService(Type serviceType)
{
if (container.IsRegistered(serviceType))
{
return container.Resolve(serviceType);
}
else
{
return null;
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
if (container.IsRegistered(serviceType))
{
return container.ResolveAll(serviceType);
}
else
{
return new List<object>();
}
}
public void Dispose()
{
container.Dispose();
}
}
public class IoCContainer : ScopeContainer, IDependencyResolver
{
public IoCContainer(IUnityContainer container)
: base(container)
{
}
public IDependencyScope BeginScope()
{
var child = this.container.CreateChildContainer();
return new ScopeContainer(child);
}
}
My IUnitOfWork code:
public interface IUnitOfWork : IDisposable
{
GenericRepository<Office> OfficeRepository { get; }
GenericRepository<Property> PropertyRepository { get; }
void Save();
void Dispose(bool disposing);
void Dispose();
}
My UnitOfWork implementation:
public class UnitOfWork : IUnitOfWork
{
private readonly PropertySearchContext _context = new PropertySearchContext();
private GenericRepository<Office> _officeRepository;
private GenericRepository<Property> _propertyRepository;
public GenericRepository<Office> OfficeRepository
{
get
{
if (this._officeRepository == null)
{
this._officeRepository = new GenericRepository<Office>(_context);
}
return _officeRepository;
}
}
public GenericRepository<Property> PropertyRepository
{
get
{
if (this._propertyRepository == null)
{
this._propertyRepository = new GenericRepository<Property>(_context);
}
return _propertyRepository;
}
}
public void Save()
{
_context.SaveChanges();
}
private bool disposed = false;
public virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
_context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
I have used unity/DI with MVC4/WebAPI controllers and this implementation of UnitOfWork many times before without issue, so I'm thinking it's Umbraco specific.
I have also debugged the application and made sure that it hits OnApplicationStarted and that its parameters are not null.
The GetAllProperties method in the controller is just a test method to make sure it is all working fine, however, when I try and access this action I get the error:
"The type IUnitOfWork does not have an accessible constructor"
Does anyone have experience with using Umbraco 6.1 and it's UmbracoApiController with dependency injection/Unity?
Also, on an unrelated note, is there a way to return JSON instead of XML in the action? In Web API you would just define the formatter in the WebApi.config but there is none in Umbraco.
Thanks,
Justin
In case you haven't found a solution to your problem? Download this nuget package and right after building your unity container:
GlobalConfiguration.Configuration.DependencyResolver =
new Unity.WebApi.UnityDependencyResolver(Bootstrapper.Container);
Notice the namespace which is different than Unity.Mvc4.UnityDependencyResolver.

How can I intercept all controller calls in an MVC application?

Is there a quick method for intercepting all controller calls in MVC-3?
For logging and testing purposes, I'd like to build a tool that can intercept all controller calls, and log which controller was called, with which message, at what time.
I can't remember where I got this from, but I was looking around for something similar a while back and found an article or something somewhere that contained this logging filter:
public class LogActionFilter : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
Log("OnActionExecuting", filterContext.RouteData);
}
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
Log("OnActionExecuted", filterContext.RouteData);
}
public override void OnResultExecuting(ResultExecutingContext filterContext)
{
Log("OnResultExecuting", filterContext.RouteData);
}
public override void OnResultExecuted(ResultExecutedContext filterContext)
{
Log("OnResultExecuted", filterContext.RouteData);
}
private void Log(string methodName, RouteData routeData)
{
var controllerName = routeData.Values["controller"];
var actionName = routeData.Values["action"];
var message = string.Format("{0} controller: {1} action: {2}", methodName, controllerName, actionName);
Debug.WriteLine(message, "Action Filter Log");
}
}
To use it, just add it to the global filters in global.asax:
public static void RegisterGlobalFilters(GlobalFilterCollection filters)
{
filters.Add(new HandleErrorAttribute());
filters.Add(new LogActionFilter());
}
I'll have a look now to see if I can find the source.
Edit: Found it. It was from this question.
Depending on how big the site is already, you could create a class in the hierarchy between the framework's Controller class and your main controllers.
Something like
public class MyBaseController : Controller {
protected override void OnActionExecuting(ActionExecutingContext filterContext) {
// your logging stuff here
base.OnActionExecuting(filtercontext);
}
}
Then the rest of your controllers can inherit from this, e.g.
public class HomeController : MyBaseController {
// action methods...
}
You can use your own controller factory and register it as well:
From: (many example on the net - insert logging where you want)
adapted from: http://www.keyvan.ms/custom-controller-factory-in-asp-net-mvc
using System;
using System.Configuration;
using System.Web.Mvc;
using System.Web.Routing;
namespace IControllerFactorySample.ControllerFactories
{
public class YourControllerFactory : IControllerFactory
{
#region IControllerFactory Members
public IController CreateController(RequestContext requestContext, string controllerName)
{
if (string.IsNullOrEmpty(controllerName))
throw new ArgumentNullException("controllerName");
IController controller = Activator.CreateInstance(Type.GetType(controllerName)) as IController;
return controller;
}
public void ReleaseController(IController controller)
{
if (controller is IDisposable)
(controller as IDisposable).Dispose();
else
controller = null;
}
#endregion
}
}
dont forget to register it in global.asax.cs
ControllerBuilder.Current.SetControllerFactory(
typeof(YourControllerFactory));
there is a routing debugger developed by Phil Haack
ASP.Net Routing Debugger

MVC3, Unity Framework and Per Session Lifetime Manager Issue

In a simple word I try to create Lifetime manager for Unity framework by using Http Session in my MVC3 project. My sample implementation of lifetime manager is:
public class UnityPerSessionLifetimeManager : LifetimeManager
{
private string sessionKey;
private HttpContext ctx;
public UnityPerSessionLifetimeManager(string sessionKey)
{
this.sessionKey = sessionKey;
this.ctx = HttpContext.Current;
}
public override object GetValue()
{
return this.ctx.Session[this.sessionKey];
}
public override void RemoveValue()
{
this.ctx.Items.Remove(this.sessionKey);
}
public override void SetValue(object newValue)
{
this.ctx.Session[this.sessionKey] = newValue;
}
}
In my global.asax.cs I replaced default controller factory with my own UnityControllerFactory
public class UnityControllerFactory : DefaultControllerFactory
{
private IUnityContainer container;
public UnityControllerFactory(IUnityContainer container)
{
this.container = container;
this.RegisterServices();
}
protected override IController GetControllerInstance(RequestContext context, Type controllerType)
{
if (controllerType != null)
{
return this.container.Resolve(controllerType) as IController;
}
return null;
}
private void RegisterServices()
{
this.container.RegisterType<IMyType, MyImpl>(new UnityPerSessionLifetimeManager("SomeKey"));
}
}
}
I set breakpoints on each function of UnityPerSessionLifetimeManager class, I noticed that when controller factory tries to solve dependencies of my controller, the HttpContext.Session is actually null, so the code fails retrieve from session or save to session.
Any idea why session is null at this stage?
My mistake, I should change code of UnityPerSessionLifetimeManager class to be
public class UnityPerSessionLifetimeManager : LifetimeManager
{
private string sessionKey;
public UnityPerSessionLifetimeManager(string sessionKey)
{
this.sessionKey = sessionKey;
}
public override object GetValue()
{
return HttpContext.Current.Session[this.sessionKey];
}
public override void RemoveValue()
{
HttpContext.Current.Session.Remove(this.sessionKey);
}
public override void SetValue(object newValue)
{
HttpContext.Current.Session[this.sessionKey] = newValue;
}
}
because when the constructor was called to register type, session state is not ready yet and I already assigned http context of that time to a variable. But in later Get/Set functions session state is ready.

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