I use the following:
public interface IRepository<T>
{
void Add(T entity);
}
public class Repository<T>
{
private readonly ISession session;
public Repository(ISession session)
{
this.session = session;
}
public void Add(T entity)
{
session.Save(entity);
}
}
public class SomeHandler : IHandleMessages<SomeMessage>
{
private readonly IRepository<EntityA> aRepository;
private readonly IRepository<EntityB> bRepository;
public SomeHandler(IRepository<EntityA> aRepository, IRepository<EntityB> bRepository)
{
this.aRepository = aRepository;
this.bRepository = bRepository;
}
public void Handle(SomeMessage message)
{
aRepository.Add(new A(message.Property);
bRepository.Add(new B(message.Property);
}
}
public class MessageEndPoint : IConfigureThisEndpoint, AsA_Server, IWantCustomInitialization
{
public void Init()
{
ObjectFactory.Configure(config =>
{
config.For<ISession>()
.CacheBy(InstanceScope.ThreadLocal)
.TheDefault.Is.ConstructedBy(ctx => ctx.GetInstance<ISessionFactory>().OpenSession());
config.ForRequestedType(typeof(IRepository<>))
.TheDefaultIsConcreteType(typeof(Repository<>));
}
}
My problem with the threadlocal storage is, is that the same session is used during the whole application thread. I discovered this when I saw the first level cache wasn't cleared. What I want is using a new session instance, before each call to IHandleMessages<>.Handle.
How can I do this with structuremap? Do I have to create a message module?
You're right in that the same session is used for all requests to the same thread. This is because NSB doesn't create new threads for each request. The workaround is to add a custom cache mode and have it cleared when message handling is complete.
1.Extend the thread storage lifecycle and hook it up a a message module
public class NServiceBusThreadLocalStorageLifestyle : ThreadLocalStorageLifecycle, IMessageModule
{
public void HandleBeginMessage(){}
public void HandleEndMessage()
{
EjectAll();
}
public void HandleError(){}
}
2.Configure your structuremap as follows:
For<<ISession>>
.LifecycleIs(new NServiceBusThreadLocalStorageLifestyle())
...
Hope this helps!
Related
I have a solution and I have different projects in it.
One of them is the api project and I want to use dependency injection in this project, but I get the following error:
Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: CCM.Business.Abstract.ICompanyService Lifetime: Scoped ImplementationType: CCM.Business.Concrete.CompanyManager': Unable to resolve service for type 'CCM.DataAccess.Concrete.CompanyDal' while attempting to activate 'CCM.Business.Concrete.CompanyManager'.)
Startup.cs:
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
services.AddScoped<ICompanyDal, CompanyDal>();
services.AddScoped<ICompanyService, CompanyManager>();
}
ICompanyDal:
public interface ICompanyDal: IGenericDal<Company>
{
}
CompanyDal:
public class CompanyDal:GenericDal<Company,CCMContext>,ICompanyDal
{
}
ICompanyService:
public interface ICompanyService
{
Company GetById(int id);
List<Company> GetAll();
void Create(Company entity);
void Update(Company entity);
void Delete(Company entity);
}
CompanyManager:
public class CompanyManager : ICompanyService
{
private CompanyDal _companyDal;
public CompanyManager(CompanyDal companyDal)
{
_companyDal = companyDal;
}
public void Create(Company entity)
{
_companyDal.Create(entity);
}
public void Delete(Company entity)
{
_companyDal.Delete(entity);
}
public List<Company> GetAll()
{
return _companyDal.GetAll();
}
public Company GetById(int id)
{
return _companyDal.GetById(id);
}
public void Update(Company entity)
{
_companyDal.Update(entity);
}
}
Is there anything else I should pass on to you? please help.
In startup, you add the service ICompanyDal with the implementation CompanyDal. But in CompanyManager, you inject the implementation CompanyDal, not the service ICompanyDal.
Solution, inject the service in the constructor :
public class CompanyManager : ICompanyService
{
private ICompanyDal _companyDal;
public CompanyManager(ICompanyDal companyDal)
{
_companyDal = companyDal;
}
...
Change the CompanyManager to explicitly depend on the registered abstraction
CompanyManager:
//...
private ICompanyDal _companyDal;
//CTOR
public CompanyManager(ICompanyDal companyDal) {
_companyDal = companyDal;
}
//...
since that is what was registered with the container
Startup:
//...
services.AddScoped<ICompanyDal, CompanyDal>();
//...
Make sure that your controller(s) follow a similar format and explicitly depends on the registered abstraction(s) as well
Controller:
//...
public MyController(ICompanyService service) {
//...
}
//...
I am getting the following error whenever I try to inject one of my service's dependency into the MVC controller:
Error activating IFeedService No matching bindings are available, and the type is not self-bindable.
Activation path:
2) Injection of dependency IFeedService into parameter svc of constructor of type FeedController
1) Request for FeedController
Suggestions:
1) Ensure that you have defined a binding for IFeedService.
2) If the binding was defined in a module, ensure that the module has been loaded into the kernel.
3) Ensure you have not accidentally created more than one kernel.
4) If you are using constructor arguments, ensure that the parameter name matches the constructors parameter name.
5) If you are using automatic module loading, ensure the search path and filters are correct.
======================================================================
Here's how my code looks like:
ObjectFactory.cs
private static void RegisterServices(IKernel kernel)
{
// Contexts
kernel.Bind<IEntityObjectContext>().To<Entities>();
kernel.Bind<IAzureObjectContext>().To<AzureTableObjectContext>();
// Repositories
kernel.Bind<IEFRepository>().To<EFRepository>();
kernel.Bind<IAzureRepository>().To<AzureRepository>();
// Services
kernel.Bind<IFeedService>().To<FeedService>();
}
IEFRepository.cs
public interface IEFRepository : IDisposable
{
void SetContext(IEntityObjectContext context);
IQueryable<T> GetAll<T>() where T : class;
}
EFRepository.cs
public class EFRepository : IEFRepository
{
internal IEntityObjectContext context;
private Dictionary<Type, object> objectSets;
public EFRepository(IEntityObjectContext context)
{
this.context = context;
objectSets = new Dictionary<Type, object>();
}
public void SetContext(IEntityObjectContext context)
{
this.context = context;
}
}
IFeedService.cs
public interface IFeedService : IDisposable
{
IQueryable<FeedItem> GetPosts();
}
FeedService.cs
public class FeedService : IFeedService
{
private IEntityObjectContext _context;
private readonly IEFRepository _repo;
public FeedService(IEntityObjectContext context,
IEFRepository repo)
{
_context = context;
_repo = repo;
_repo.SetContext(_context);
}
public IQueryable<FeedItem> GetPosts()
{
using (_repo)
{
return _repo.GetAll<FeedItem>().Take(10);
}
}
}
FeedController.cs
public class FeedController : Controller
{
private readonly IFeedService _svc;
public FeedController(IFeedService svc)
{
_svc = svc;
}
}
As you can see, there are some nested dependency there in action. Not sure though, what needs to be added/removed for this bit to work.
Note: The error is thrown whenever I request the Feed/FetchFeed path. I also tried to comment out the FeedService's constructor portion to see if the nested dependencies are creating any problem, but again same error was thrown.
EDIT 1:
Rest of the code for the ObjectFactory.cs
class ObjectFactory
{
static ObjectFactory()
{
RegisterServices(kernel);
}
static IKernel kernel = new StandardKernel();
public static T GetInstance<T>()
{
return kernel.Get<T>();
}
private static void RegisterServices(IKernel kernel)
{
//...
}
}
EDIT 2:
I even tried to write a fairly basic service, but still the same error. Here's what I tried with:
public interface ITest
{
void CheckItOut();
}
public class Test : ITest
{
public void CheckItOut()
{
}
}
ObjectFactory.cs
kernel.Bind<ITest>().To<Test>();
I'm using ASP.NET MVC 4 with Entity Framework 5. I have model classes and Entity Maps to map existing tables to those model classes. All this is setup fine and works great.
Now I want to mock this. I created Unit Of Work that takes the DataContext and uses a Generic Repository. Upon that I built services to be able to get data from many repositories at once and only needing to have one instance of the DataContext. This also works great.
Now to the problem: I want to test the services, with mock data. When I create the Unit Of Work instance, I want to be able to insert a DataContext that is mocked instead of the real DataContext.
I tried to create a IContext interface and let the real and mocked DataContext implement that but ran into problems with DbSet. I tried to use IDbSet and creating a FakeDbSet but without success. I also read on the internet that mocking the context with IDbSet and using a FakeDbSet is a bad approach.
Do you have any idea what would be the best way to achieve this? What I have now is the behavior I would like to keep, but would really like to be able to mock the data from the Model classes in the DataContext.
I'm aware of that Entity Framework already comes with Unit Of Work behavior and that you don't need to add extra behavior on top of that. But I wanted to wrap that inside of another class that keeps track of all the repositories (called UnitOfWork class).
Edit: I wrote two articles explaining my solution with both LINQ and Entity Framework.
http://gaui.is/how-to-mock-the-datacontext-linq/
http://gaui.is/how-to-mock-the-datacontext-entity-framework/
Here's my code:
IRepository.cs
public interface IRepository<T> where T : class
{
void Add(T entity);
void Delete(T entity);
void Update(T entity);
T GetById(long Id);
IEnumerable<T> All();
IEnumerable<T> Find(Expression<Func<T, bool>> predicate);
}
IUnitOfWork.cs
public interface IUnitOfWork : IDisposable
{
IRepository<TEntity> GetRepository<TEntity>() where TEntity : class;
void Save();
}
Repository.cs
public class Repository<T> : IRepository<T> where T : class
{
private readonly IDbContext _context;
private readonly IDbSet<T> _dbset;
public Repository(IDbContext context)
{
_context = context;
_dbset = context.Set<T>();
}
public virtual void Add(T entity)
{
_dbset.Add(entity);
}
public virtual void Delete(T entity)
{
var entry = _context.Entry(entity);
entry.State = System.Data.EntityState.Deleted;
}
public virtual void Update(T entity)
{
var entry = _context.Entry(entity);
_dbset.Attach(entity);
entry.State = System.Data.EntityState.Modified;
}
public virtual T GetById(long id)
{
return _dbset.Find(id);
}
public virtual IEnumerable<T> All()
{
return _dbset;
}
public IEnumerable<T> Find(Expression<Func<T, bool>> predicate)
{
return _dbset.Where(predicate);
}
}
UnitOfWork.cs
public class UnitOfWork<TContext> : IUnitOfWork where TContext : IDbContext, new()
{
private readonly IDbContext _ctx;
private Dictionary<Type, object> _repositories;
private bool _disposed;
public UnitOfWork()
{
_ctx = new TContext();
_repositories = new Dictionary<Type, object>();
_disposed = false;
}
public IRepository<TEntity> GetRepository<TEntity>() where TEntity : class
{
if (_repositories.Keys.Contains(typeof(TEntity)))
return _repositories[typeof(TEntity)] as IRepository<TEntity>;
var repository = new Repository<TEntity>(_ctx);
_repositories.Add(typeof(TEntity), repository);
return repository;
}
public void Save()
{
_ctx.SaveChanges();
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (!this._disposed)
{
if (disposing)
{
_ctx.Dispose();
}
this._disposed = true;
}
}
}
ExampleService.cs
public class ExampleService
{
private IRepository<Example> m_repo;
public ExampleService(IUnitOfWork uow)
{
m_repo = uow.GetRepository<Example>();
}
public void Add(Example Example)
{
m_repo.Add(Example);
}
public IEnumerable<Example> getAll()
{
return m_repo.All();
}
}
ExampleController.cs
public IEnumerable<Example> GetAll()
{
// Create Unit Of Work object
IUnitOfWork uow = new UnitOfWork<AppDataContext>();
// Create Service with Unit Of Work attached to the DataContext
ExampleService service = new ExampleService(uow);
return service.getAll();
}
Your ExampleService class is expecting IUnitOfWork, that means you just need another IUnitOfWork that is a Mock and its GetRepository() method will return an IRepository Mock.
For example (not really a Mock but In-Memory stub):
public InMemoryRepository<T> : IRepository<T> where T : class
{
........
}
public InMemoryUnitOfWork : IUnitOfWork
{
public IRepository<TEntity> GetRepository<TEntity>() where TEntity : class
{
return new InMemoryRepository<TEntity>();
}
}
Then:
public IEnumerable<Example> GetAll()
{
// Create Unit Of Work object
IUnitOfWork uow = new InMemoryUnitOfWork();
// Create Service with Unit Of Work
ExampleService service = new ExampleService(uow);
return service.getAll();
}
You can follow the following link it is very helpful.
Generic Repository Pattern in MVC3 Application with Entity Framework
Entity Framework and Data Patterns
I want to have my own AppContext in my ApiController (MVC4).
Should be something like
public class TestController : BaseApiController
{
[HttpGet]
public IEnumerable<TestVM> GetAll()
{
// the test service is injected with SimpleInjector
return _testService.GetAll(**base.AppContext**);
}
}
but the ApiController haven't access to the Session.
Are there any solutions to "activate" the Session for specific keys (because I don't want the whole Session)?
Or do you have any other idea (cache or cookie)?
This is the BaseApiController
public abstract class BaseApiController: ApiController
{
public IAppContext AppContext
{
get { return SessionState.AppContext; }
}
}
and this is my IAppContext (it will have more properties in the future)
public interface IAppContext
{
IIdentity User { get; }
/// <summary> Gets the user id. </summary>
/// <value>The user id.</value>
int IdUser { get; }
}
here the application module which is registered in the web.config
public class ApplicationModule : IHttpModule
{
// ...
SessionState.AppContext = _appContext.InitializeNew(
HttpRuntime.AppDomainAppPath, languages);
// ...
}
SessionState class to get the AppContext
public class SessionState : BaseSessionVariables
{
public static IAppContext AppContext
{
get { return SessionState.Get<IAppContext>("AppContext"); }
set { SessionState.Set("AppContext", value); }
}
}
here the BaseSessionVariables class
public static HttpSessionState GetSession()
{
return HttpContext.Current.Session;
}
protected static T Get<T>(string key) where T : class
{
var session = BaseSessionVariables.GetSession();
if (session == null)
{
throw new Exception("No session");
}
return (session[key] as T);
}
Thanks for your help!
Take a look at the implementation below. It should get you headed in the right direction.
Updated IAppContext - Added Setters
public interface IAppContext
{
IIdentity User { get; set; }
/// <summary> Gets the user id. </summary>
/// <value>The user id.</value>
int IdUser { get; set; }
}
Updated Base Controller - Instantiates a new AppContextImplemenation in the OnActionExecuting method
public abstract class BaseApiController: ApiController
{
public IAppContext AppContext {get; set;}
protected override void OnActionExecuting(
ActionExecutingContext filterContext)
{
AppContext = new AppContextImplementation();
}
}
New Class - implements IAppContext and wraps the HttpContext Session. For testing you can then create an TestAppContextImplementation that doesn't rely on Session but some other in memory storage mechanism.
public class AppContextImplementation : IAppContext
{
public IIdentity User
{
get { return HttpContext.Current.Session["User"] as IIdentity; }
set { HttpContext.Current.Session["User"] = value; }
}
int IdUser
{
get { return Convert.ToInt32(Session["IdUser"]); }
set { Session["IdUser"] = value; }
}
}
For ApiControllers, build yourself a DelegatingHandler and push all of your goodies onto request.Properties. You can then retrieve them from your request whether you are testing or running live. The benefit is that you then have zero dependency on Session in your Controller.
MessageHandler
public class ContextHandler : DelegatingHandler
{
protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken)
{
// get the goodies to add onto the request
var goodies = /* call to goodieGoodieYumYum */
// add our goodies onto the request
request.Properties.Add(Constants.RequestKey_Goodies, goodies);
// pass along to the next handler
return base.SendAsync(request, cancellationToken);
}
}
Controller Action
var goodies = (List<Goodie>)Request.Properties[Constants.RequestKey_Goodies];
I can't get rid of the exception which comes from Ninject "Several constructors have the same priority"
I have repository
public interface IRepository<TEntity> where TEntity : class
{
List<TEntity> FetchAll();
IQueryable<TEntity> Query { get; }
void Add(TEntity entity);
void Delete(TEntity entity);
void Save();
}
public class Repository<T> : IRepository<T> where T : class
{
private readonly DataContext _db;
public Repository(DataContext db)
{
_db = db;
}
#region IRepository<T> Members
public IQueryable<T> Query
{
get { return _db.GetTable<T>(); }
}
public List<T> FetchAll()
{
return Query.ToList();
}
public void Add(T entity)
{
_db.GetTable<T>().InsertOnSubmit(entity);
}
public void Delete(T entity)
{
_db.GetTable<T>().DeleteOnSubmit(entity);
}
public void Save()
{
_db.SubmitChanges();
}
#endregion
}
Controller where I am trying to bind repository
public class AdminController : Controller
{
private readonly IRepository<Store> _storeRepository;
public AdminController(IRepository<Store> storeRepository)
{
_storeRepository = storeRepository;
}
}
Ninject boot strapper
private static void RegisterServices(IKernel kernel)
{
var connectionString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
kernel.Bind(typeof (DataContext)).ToMethod(context => new DataContext(connectionString));
kernel.Bind(typeof(IRepository<>)).To(typeof(Repository<>));
}
After I run app I get error
Error activating DataContext using implicit self-binding of DataContext
Several constructors have the same priority. Please specify the constructor using ToConstructor syntax or add an Inject attribute.
Constructors:
DataContext(string fileOrServerOrConnectionMappingSource mapping)
DataContext(IDbConnection connectionMappingSource mapping)
It seems that Ninject tries to bind to DataContext class constructor
namespace System.Data.Linq: IDisposable
{
public class DataContext : IDisposable
{
public DataContext(IDbConnection connection);
public DataContext(string fileOrServerOrConnection);
//skip code
}
but I want to bind to my repository constructor
public class Repository<T> : IRepository<T> where T : class
{
private readonly DataContext _db;
public Repository(DataContext db)
{
_db = db;
}
//skip code
}
Also if I remove line below form boot strapper I still get the same exception. It seems Ninject automatically tries to bind dependencies when I am trying to bind Repository.
kernel.Bind(typeof (DataContext)).ToMethod(context => new DataContext(connectionString));