i am creating custom membership provider using ninject for binding to sql classes.
my class in looks like
public MyMembershipProvider(IUsersRepository userRepository)
{
this.userRepository = userRepository;
}
How can i create from this parameterless constructor?
kernel.Bind<IUsersRepository>().To<UsersRepository>();
kernel.Bind<MembershipProvider>().To<MyMembershipProvider>();
and then:
public class AccountController : Controller
{
private readonly MembershipProvider _membershipProvider;
public AccountController(MembershipProvider membershipProvider)
{
_membershipProvider = membershipProvider;
}
public ActionResult Foo()
{
// TODO: Use the membership provider to do some processing
return View();
}
}
Related
I am struggling with wiring dependencies through autofac in my WebApi 2 project. I have a following interface and class that i'd like to inject in my GET and POST controller actions,
public interface IRepository
{
IContext Context
{
get;
}
void SomeOperation();
}
public MyRepository : IRepository
{
IContext _context;
public MyRepository(IContext context)
{
_context = context;
}
public Context
{
get
{
return _context;
}
}
public void SomeOperation
{
// Perform some operation using _context;
}
}
I 'd like IRepository to be injected in controller like this,
public class MyController : ApiController
{
private readonly IRepository _repo;
public ApplicationsController(IRepository repo)
{
_repo = repo;
}
// GET: api/v1/Contexts({contextId})
public IHttpActionResult Get(string contextId)
{
_repo.SomeOperation();
}
}
IContext object to be injected in MyRepository has to be fetched from a factory, something like this
public class ContextFactory
{
Hashtable contextMap;
IContext Get(string contextId)
{
if contextMap.Contains(contextId)
return contextMap[contextId].Value;
else
{
IContextConfiguration configuration = ContextConfigurationFactory.Get(contextId);
IContext context = new ConcreteContext(configuration);
contextMap.Add[contextId, context];
return context;
}
}
}
I am not sure how to wire all the classes and convert logic in factory classes by injecting relationships through Autofac so that context id passed in url is passed to ContextConfigurationFactory.Get and instantiate ConcreteContext object when not found in hash and eventually Autofac injecting right context object in MyRepository before passing it on to Get action in the controller.
Let's simplify this a bit. What you're trying to do is:
Get the context ID from a route parameter.
Use that route parameter in the factory to create a context.
The rest seems pretty much peripheral - the repository, the controller, all that. The crux of the question is that you need to get a route parameter into your factory.
Given that, let's put together some simplified code:
public class ContextFactory
{
public IContext Get(string contextId)
{
return new Context(contextId);
}
}
public interface IContext
{
string Id { get; }
}
public class Context : IContext
{
public Context(string id)
{
this.Id = id;
}
public string Id { get; private set; }
}
That's basically what you have:
An IContext interface that things need.
A ContextFactory that is basically responsible for building these things.
A Context concrete implementation of IContext that is built by the factory.
I would probably do something like this:
var builder = new ContainerBuilder();
builder.RegisterType<ContextFactory>();
builder.Register(ctx =>
{
var routeData = HttpContext.Current.Request.RequestContext.RouteData;
var id = routeData.Values["contextId"] as string;
var factory = ctx.Resolve<ContextFactory>();
return factory.Get(id);
}).As<IContext>()
.InstancePerLifetimeScope();
Now when you resolve IContext it will use your factory, get the current context ID from route data, and pass it through the factory.
I will leave the following for you to look into:
What happens if the route parameter isn't there? (Autofac won't let you return null.)
What happens if the route parameter has invalid data?
The route parameter is pretty hackable, is this a security risk?
...and so on.
I have just landed in dependency injection world.
I have the following custom DbContext-
public partial class SkyTrackerContext: DbContext
{
public SkyTrackerContext(): base()
{
Database.SetInitializer(new SkyTrackerDBInitializer());
}
}
Would like inject SkyTrackerContext in this base controller-
public abstract class BaseController : Controller
{
public BaseController() {}
[Inject]
public SkyTrackerContext MyDbContext { get; set; }
}
Sample usage-
public class LoginController : BaseController
{
public ActionResult ValidateLogin(Login login)
{
var query = MyDbContext.Persons.Where(.....);
}
}
What should I write in NinjectWebCommon.cs to inject this context ?
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);
return kernel;
}
catch
{
kernel.Dispose();
throw;
}
}
First, you should avoid method injection. Instead, use constructor injection. In other words:
public abstract class BaseController : Controller
{
protected readonly DbContext context;
public BaseController(DbContext context)
{
this.context = context;
}
...
}
Then, as far as the Ninject config goes, it's extremely simple:
kernel.Bind<DbContext>().To<SkyTrackerContext>().InRequestScope();
I'd like to implement the Decorator pattern in one of my Mvx projects. That is, I'd like to have two implementations of the same interface: one implementation that is available to all of the calling code, and another implementation that is injected into the first implementation.
public interface IExample
{
void DoStuff();
}
public class DecoratorImplementation : IExample
{
private IExample _innerExample;
public Implementation1(IExample innerExample)
{
_innerExample = innerExample;
}
public void DoStuff()
{
// Do other stuff...
_innerExample.DoStuff();
}
}
public class RegularImplementation : IExample
{
public void DoStuff()
{
// Do some stuff...
}
}
Is it possible to wire up the MvvmCross IoC container to register IExample with a DecoratorImplementation containing a RegularImplementation?
It depends.
If DecoratorImplementation is a Singleton, then you could do something like:
Mvx.RegisterSingleton<IExample>(new DecoratorImplementation(new RegularImplementation()));
Then calls to Mvx.Resolve<IExample>() will return the instance of DecoratorImplementation.
However, if you need a new instance, unfortunately the MvvmCross IoC Container doesn't support that. It would be nice if you could do something like:
Mvx.RegisterType<IExample>(() => new DecoratorImplementation(new RegularImplementation()));
Where you'd pass in a lambda expression to create a new instance, similar to StructureMap's ConstructedBy.
Anyway, you may need to create a Factory class to return an instance.
public interface IExampleFactory
{
IExample CreateExample();
}
public class ExampleFactory : IExampleFactory
{
public IExample CreateExample()
{
return new DecoratorImplementation(new RegularImplementation());
}
}
Mvx.RegisterSingleton<IExampleFactory>(new ExampleFactory());
public class SomeClass
{
private IExample _example;
public SomeClass(IExampleFactory factory)
{
_example = factory.CreateExample();
}
}
The projects in my solution are set up like this:
App.Data
App.Models
App.Web
In App.Data, I'm using Entity Framework to access my data with a bunch of Repositories to abstract interaction with it. For obvious reasons, I would like my App.Web to reference only the App.Data project and not Entity Framework.
I'm using Constructor Injection to give my Controllers a reference to a Repository container that looks like this:
public interface IDataRepository
{
IUserRepository User { get; set; }
IProductRepository Product { get; set; }
// ...
}
public class DataRepository : IDataRepository
{
private readonly AppContext _context;
public DataRepository(AppContext context)
{
_context = context;
}
// ...
}
DataRepository will have a AppContext object (which inherits from Entity Framework's DbContext) that all the child Repositories will use to access the database.
So finally we come to my problem: how do I use Constructor Injection on DataRepository considering it's a code library and has no entry-point? I can't bootstrap AppContext in App.Web because then I have to reference Entity Framework from that project.
Or am I just doing something stupid?
You can define a RepositoryConnection class in App.Data that acts as a wrapper to the Context and removes the need to reference EF in App.Web. If you are using an IoC Container you can control the lifetime of the RepositoryConnection class to ensure that all instances of Repository get the same Context. This is a simplified example ...
public class RepositoryConnection
{
private readonly AppContext _context;
public RepositoryConnection()
{
_context = new AppContext();
}
public AppContext AppContext { get { return _context; } }
}
public class DataRepository : IDataRepository
{
private readonly AppContext _context;
public DataRepository(RepositoryConnection connection)
{
_context = connection.AppContext;
}
// ...
}
I would like to how to correct build and handle with NHibernate repository and session in view models classes.
For example I use Caliburn Micro framework with Castle Windsor boostraper.
First I created NHibernate repository:
public interface IRepository{//I omitted not needed code for simplification}
public class NHibRepository: IRepository
{
private ISession _session;
public NHibRepository(ISession session)
{
_session=session;
}
// I omitted not needed code for simplification
}
Second I definied some POCO class and mapping class with Fluent NHibernate.
public class User{}
public class Profile{}
public class Album{}
public class UserMap : ClassMap<User>{}
public class ProfileMap : ClassMap<Profile>{}
public class AlbumMap : ClassMap<Album>{}
Now I need use NHibernate repositories in my view models.
public interface IViewModelA{}
public class ViewModelA : ScreenViewModel, IViewModelA
{
public NHibRepository<User> UserRepo{get;set;}
public NHibRepository<Profile> ProfileRepo{get;set;}
}
public interface IViewModelB{}
public class ViewModelB : Screen, IViewModelB
{
public NHibRepository<Profile> ProfileRepo{get;set;}
public NHibRepoistory<Album> AlbumRepo{get;set;}
}
When I am creating repository class for some entity class I need pass session to NHibRepository construtor.
UserRepo= new NHibRepository<User>(NHIBERNATE SESSION);
Until now I used some helper class for creating Nhibernate session and init repository.
Helper class is here:
public class FluentNHibHelper
{
private ISessionFactory _sessionFactory;
public FluentNHibHelper(IPersistenceConfigurer db, Assembly asm)
{
InitializeSessionFactory(db, asm);
}
private void InitializeSessionFactory(IPersistenceConfigurer db, Assembly asm)
{
_sessionFactory = Fluently.Configure()
.Database(db)
.Mappings(m => m.FluentMappings.AddFromAssembly(asm))
.ExposeConfiguration(cfg => new SchemaUpdate(cfg).Execute(true, true))
.BuildSessionFactory();
}
public ISession OpenSession()
{
return _sessionFactory.OpenSession();
}
}
with this class I created repository class:
private const string ConnString =
#"Server=TestMachine\SQLEXPRESS;Database=TEST;Trusted_Connection=True;";
UserRepo = new NHibRepository<User>(
new FluentNHibHelper(MsSqlConfiguration.MsSql2008.ConnectionString(ConnString),
Assembly.GetExecutingAssembly())
.OpenSession());
Now I am confuse I don’t what is the best way for creating repository object in view models.
For example in bootstraper class can I somehow register repository class ?
public class CastleBootstrapper : Bootstrapper<IShellViewModel>
{
private IWindsorContainer _windsorContainer;
protected override void Configure()
{
_windsorContainer = new WindsorContainer();
//register repository class here ???
}
}
Can anybody help me? Thank you very much
Sorry for my english.
I use the following in an ASP.net MVC application. Castle.Windsor takes care of creating the ISession dependency for each repository.
//Located in your application startup
protected IWindsorContainer CreateContainer()
{
container = new WindsorContainer();
container.Install(
new PersistenceInstaller(),
new RepositoryInstaller()
//, other installers here
);
return container;
}
public class PersistenceInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.AddFacility<PersistenceFacility>();
}
}
public class PersistenceFacility : AbstractFacility
{
protected override void Init()
{
NHibernate.Cfg.Configuration config = BuildDatabaseConfiguration();
Kernel.Register(
Component.For<ISessionFactory>()
.UsingFactoryMethod(config.BuildSessionFactory),
Component.For<ISession>()
.UsingFactoryMethod(k => k.Resolve<ISessionFactory>().OpenSession())
.LifeStyle.Trasient
);
}
private NHibernate.Cfg.Configuration BuildDatabaseConfiguration()
{
return Fluently.Configure()
.Database(SetupDatabase)
.Mappings(m => m.HbmMappings.AddFromAssemblyOf<Entity>())
.ExposeConfiguration(ConfigurePersistence)
.BuildConfiguration();
}
protected virtual IPersistenceConfigurer SetupDatabase()
{
return MsSqlConfiguration.MsSql2008
.UseOuterJoin()
.ConnectionString(x => x.FromConnectionStringWithKey("ApplicationServices"))
.ShowSql();
}
protected virtual void ConfigurePersistence(NHibernate.Cfg.Configuration config)
{
SchemaMetadataUpdater.QuoteTableAndColumns(config);
}
protected virtual bool IsDomainEntity(Type t)
{
return typeof(DomainBase).IsAssignableFrom(t);
}
}
public class RepositoryInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register(Find().Configure(ConfigureLifeStyle()));
}
private ConfigureDelegate ConfigureLifeStyle()
{
return c => c.LifeStyle.Transient;
}
private BasedOnDescriptor Find()
{
return AllTypes.FromAssemblyContaining<NHRepository>()
.Where(type => type.Name.EndsWith("Repository"))
.WithService
.AllInterfaces();
}
}