I created a .NET Core 6 MVC app using Dependency Injection and Repository Pattern to inject a repository into my controller, but it gives me an error
InvalidOperationException: Unable to resolve service for type 'AqcCalama.Repositories.RepositoryPersonal' while attempting to activate 'AqcCalama.Controllers.PersonalController'.
Repository:
public class RepositoryPersonal
{
private ApplicationDbContext context;
public RepositoryPersonal(ApplicationDbContext context)
{
this.context = context;
}
public List<Personal> GetPersonal()
{
return this.context.Personal.ToList();
}
public List<Personal> GetPersonal(string rut)
{
var consulta = from datos in this.context.Personal
where datos.Rut.Contains(rut)
select datos;
return consulta.ToList();
}
Controller:
public class PersonalController : Controller
{
private RepositoryPersonal repo;
public PersonalController(RepositoryPersonal repo)
{
this.repo = repo;
}
public IActionResult Index()
{
return View();
}
public IActionResult BuscadorPersonal()
{
return View();
}
[HttpPost]
public IActionResult BuscadorPersonal(string rut)
{
List<Personal> per = this.repo.GetPersonal(rut);
return View(per);
}
program.cs
builder.Services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));
builder.Services.AddDefaultIdentity<IdentityUser>().AddEntityFrameworkStores<ApplicationDbContext>();
builder.Services.AddControllersWithViews();
I am a bit lost, Any idea what it could be?
Related
I am using ASP.NET Core 2.0
At Startup.cs I have
services.AddDbContext<MailDBServicesContext>(optionsSqLite =>
{
optionsSqLite.UseSqlite("Data Source=Mail.db");
});
I have created a model and a DbContext where DbContext is:
public class MailDBServicesContext : DbContext
{
public MailDBServicesContext(DbContextOptions<MailDBServicesContext> options)
: base(options)
{
}
public DbSet<MailCountSentErrorMails> DbSetMailCountSentErrorMails { get; set; }
}
from a Class helper I need to pass DbContextOptions and my question is how can I tell to use the options from the Startup.cs ConfigureServices method
using (var db = new MailDBServicesContext())
{
}
It should be enough to simply inject MailDBServicesContext into your controller or a service class, for example.
public class SomeDataService
{
private readonly MailDBServicesContext _dbContext;
public SomeDataService(MailDBServicesContext dbContext)
{
_dbContext = dbContext ?? throw new ArgumentNullException(nameof(dbContext));
}
public async Task AddMailCounts()
{
_dbContext.DbSetMailCountSentErrorMails
.Add(new MailCountSentErrorMails { CountSentMails = 55 });
await _dbContext.SaveChangesAsync();
}
}
Other DB context configuration options are defined in Configuring a DbContext on MSDN.
Update
Make sure to register your service in DI, i.e. ConfigureServices method.
public void ConfigureServices(IServiceCollection services)
{
services.AddTransient<ISomeDataService, SomeDataService>();
services.AddDbContext<MailDBServicesContext>(optionsSqLite =>
{
optionsSqLite.UseSqlite("Data Source=Mail.db");
});
services.AddMvc();
}
Then make a call to AddMailCounts() in your controller.
public class HomeController : Controller
{
private readonly ISomeDataService _dataService;
public HomeController(ISomeDataService dataService)
{
_dataService = dataService ?? throw new ArgumentNullException(nameof(dataService));
}
public IActionResult Index()
{
_dataService.AddMailCounts();
return View();
}
}
Now every time you load homepage, a record is inserted into DbSetMailCountSentErrorMails table.
You can find working solution on my GitHub.
I've been at it for days, but I can't get Unity to inject anything with RegisterType<> into my Controller. I'm using Web Api 2, in Visual Studio 2015, with Unity 4. Whenever I try to inject IUnitOfWork or IRFContext, I get "message": "An error occurred when trying to create a controller of type 'ClPlayersController'. Make sure that the controller has a parameterless public constructor.".
I'm using the Unity.AspNet.WebApi to bootstrapp into WebApi. Below is my UnityWebApiActivator
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(mycompany.project.api.UnityWebApiActivator), "Start")]
[assembly: WebActivatorEx.ApplicationShutdownMethod(typeof(mycompany.project.api.UnityWebApiActivator), "Shutdown")]
namespace mycompany.project.api
{
public static class UnityWebApiActivator
{
public static void Start()
{
var resolver = new UnityDependencyResolver(UnityConfig.GetConfiguredContainer());
GlobalConfiguration.Configuration.DependencyResolver = resolver;
}
public static void Shutdown()
{
var container = UnityConfig.GetConfiguredContainer();
container.Dispose();
}
}
}
I'm using a Start.cs due to Owin.
[assembly: OwinStartup(typeof(mycompany.project.api.Startup))]
namespace mycompany.project.api
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
HttpConfiguration config = new HttpConfiguration();
ConfigureOAuth(app);
config.DependencyResolver = new UnityDependencyResolver(UnityConfig.GetConfiguredContainer());
WebApiConfig.Register(config);
app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
app.UseWebApi(config);
}
public void ConfigureOAuth(IAppBuilder app)
{
OAuthAuthorizationServerOptions OAuthServerOptions = new OAuthAuthorizationServerOptions()
{
AllowInsecureHttp = true,
TokenEndpointPath = new PathString("/token"),
AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
Provider = new SimpleAuthorizationServerProvider(),
RefreshTokenProvider = new SimpleRefreshTokenProvider()
};
// Token Generation
app.UseOAuthAuthorizationServer(OAuthServerOptions);
app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
}
}
}
My WebApiConfig.cs is below:
namespace mycompany.project.api
{
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
log4net.Config.XmlConfigurator.Configure();
config.MapHttpAttributeRoutes();
config.EnableSystemDiagnosticsTracing();
config.Services.Add(typeof(IExceptionLogger),
new SimpleExceptionLogger(new LogManagerAdapter()));
config.Services.Replace(typeof(IExceptionHandler), new GlobalExceptionHandler());
}
}
}
My UnityConfig.cs is below
namespace mycompany.project.api
{
public class UnityConfig
{
#region Unity Container
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
#endregion
public static void RegisterTypes(IUnityContainer container)
{
var config = new MapperConfiguration(cfg =>
{
//AutoMapper bindings
});
container.RegisterInstance<IMapper>(config.CreateMapper());
container.RegisterType<IRFContext, RFContext>(new PerThreadLifetimeManager());
container.RegisterType<IUnitOfWork, UnitOfWork>();
XmlConfigurator.Configure();
var logManager = new LogManagerAdapter();
container.RegisterInstance<ILogManager>(logManager);
}
}
}
All that I have in my Global.asax is below:
public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Error()
{
var exception = Server.GetLastError();
if (exception != null)
{
var log = new LogManagerAdapter().GetLog(typeof(WebApiApplication));
log.Error("Unhandled exception.", exception);
}
}
}
If my Controller is like this, it works fine:
public class ClPlayersController : ApiController
{
private readonly IMapper mapper;
public ClPlayersController(IMapper _mapper, IUnityContainer container)
{
mapper = _mapper;
}
But placing IUnitOfWork, like below, or the IRFContext, I get the error:
private readonly IMapper mapper;
private readonly IUnitOfWork unitOfWork;
public ClPlayersController(IMapper _mapper, IUnityContainer container, IUnitOfWork _unitOfWork)
{
mapper = _mapper;
unitOfWork = _unitOfWork;
}
I can't find, for the life of me, what I'm doing wrong. If I loop through the container.Registrations on the constructor, I find the mappings, but they refuse to get injected. Any hints?
EDIT
Below is the code for UnitOfWork and RFContext
namespace mycompany.project.data.configuracao
{
public class UnitOfWork : IUnitOfWork
{
private readonly IRFContext _rfContext;
private bool _disposed = false;
public UnitOfWork(IRFContext rfContext)
{
_rfContext = rfContext;
}
public void Commit()
{
if (_disposed)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
_rfContext.SaveChanges();
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (_disposed) return;
if (disposing && _rfContext != null)
{
_rfContext.Dispose();
}
_disposed = true;
}
}
}
and
namespace mycompany.project.data.configuracao
{
public interface IUnitOfWork : IDisposable
{
void Commit();
}
}
and RFContext is a basic POCO generated DBContext
namespace mycompany.project.data.configuracao
{
using System.Linq;
public class RFContext : System.Data.Entity.DbContext, IRFContext
{
public System.Data.Entity.DbSet<ClGrupoEconomico> ClGrupoEconomicoes { get; set; }
//all my DbSets
public System.Data.Entity.DbSet<SpTipoLog> SpTipoLogs { get; set; }
static RFContext()
{
System.Data.Entity.Database.SetInitializer<RFContext>(null);
}
public RFContext()
: base("Name=RFContext")
{
}
public RFContext(string connectionString)
: base(connectionString)
{
}
public RFContext(string connectionString, System.Data.Entity.Infrastructure.DbCompiledModel model)
: base(connectionString, model)
{
}
public RFContext(System.Data.Common.DbConnection existingConnection, bool contextOwnsConnection)
: base(existingConnection, contextOwnsConnection)
{
}
public RFContext(System.Data.Common.DbConnection existingConnection, System.Data.Entity.Infrastructure.DbCompiledModel model, bool contextOwnsConnection)
: base(existingConnection, model, contextOwnsConnection)
{
}
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
}
protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Configurations.Add(new ClGrupoEconomicoConfiguration());
//all my Configuration classes
modelBuilder.Configurations.Add(new SpTipoLogConfiguration());
}
public static System.Data.Entity.DbModelBuilder CreateModel(System.Data.Entity.DbModelBuilder modelBuilder, string schema)
{
modelBuilder.Configurations.Add(new ClGrupoEconomicoConfiguration(schema));
//all my configuration classes
modelBuilder.Configurations.Add(new SpTipoLogConfiguration(schema));
return modelBuilder;
}
}
}
Unfortunately the exception you are seeing can occur for several reasons. One of them is when Unity cannot resolve one or more of your injections.
An error occurred when trying to create a controller of type
'FooController'. Make sure that the controller has a parameterless
public constructor.
So, based on the information in your question your setup is apparently correct, since IMapper can be injected. Therefore I guess that UnitOfWork and RFContext have dependencies that Unity cannot resolve. Maybe a repository?
UPDATE:
The problem here is that your RFContext has several constructors.
https://msdn.microsoft.com/en-us/library/cc440940.aspx#cnstrctinj_multiple
When a target class contains more than one constructor with the same
number of parameters, you must apply the InjectionConstructor
attribute to the constructor that the Unity container will use to
indicate which constructor the container should use. As with automatic
constructor injection, you can specify the constructor parameters as a
concrete type, or you can specify an interface or base class for which
the Unity container contains a registered mapping.
In this case Unity doesn't know how to resolve your RFContext, and will try to use the constructor with the most parameters. You can solve it by using
container.RegisterType<IRFContext, RFContext>(new InjectionConstructor());
I am working on an ASP.NET WebAPI using OWIN. To manage the instances of DBContext (Entity Framework), I try to use Ninject. However, when I call a controller, the programm returns an error:
The controller cannot be created, missing constructor.
Could you tell me what is going wrong here?
My Controller Class:
public class Testcontroller
{
private IApplicationDbContext _context;
public Testcontroller(IApplicationDbContext context)
{
_context = context;
}
}
This is the Ninject-File:
public static class NinjectWebCommon
{
private static readonly Bootstrapper bootstrapper = new Bootstrapper();
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
}
public static void Stop()
{
bootstrapper.ShutDown();
}
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
try
{
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
kernel.Bind<IApplicationDbContext>().To<ApplicationDbContext>();
GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(kernel);
RegisterServices(kernel);
return kernel;
}
catch
{
kernel.Dispose();
throw;
}
}
private static void RegisterServices(IKernel kernel)
{
}
}
Ninject Dependency Scope:
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());
}
}
The Entity Framework DbContext-Class:
public class ApplicationDbContext : IdentityDbContext<ApplicationUser>, IApplicationDbContext
{
public ApplicationDbContext()
: base("DefaultConnection", throwIfV1Schema: false)
{
Configuration.ProxyCreationEnabled = false;
Configuration.LazyLoadingEnabled = false;
}
public virtual DbSet<Models.Team> Teams { get; set; }
public static ApplicationDbContext Create()
{
return new ApplicationDbContext();
}
}
public interface IApplicationDbContext
{
DbSet<Models.Team> Teams { get; set; }
int SaveChanges();
Task<int> SaveChangesAsync(CancellationToken cancellationToken);
}
I tried to follow this tutorial: http://www.peterprovost.org/blog/2012/06/19/adding-ninject-to-web-api
What have I done wrong here?
Thanks in advance!
Unless there was a serious omission in you controller code, your controller is not inheriting from ApiController, as is expected with Web Api
public class TestController : ApiController {
private IApplicationDbContext _context;
public Testcontroller(IApplicationDbContext context) {
_context = context;
}
}
UPDATE
I tried to set up everything from scratch using this: http://www.alexzaitzev.pro/2014/11/webapi2-owin-and-ninject.html
For some reason, it now works out perfectly fine.
Thank you for your support!
Trying to learn ASP MVC coming from Linux/LAMP background (in other words I'm a newb) ...
For some reason I can't seem to use a function defined in a controller in another controller.
Here's the function in my MessagesController.cs file:
public List<Message> GetMessagesById(string username)
{
return db.Messages.Where(p => p.user == username).ToList();
}
When I try to reference it:
using LemonadeTrader.Models;
using LemonadeTrader.Controllers; // added this to pull the Messages::getMesssagesById
...
ViewBag.messages = lemondb.Messages.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString());
I get something along the lines of lemondb.Messages does not contain a method called GetMesssagesById.
How do I reference it?
You shouldn't be linking controller methods like this, not to mention that controllers shouldn't be performing data access directly. I would recommend you externalizing this function into a separate class/repository which could be used by both controllers.
Example:
public class MessagesRepository
{
public List<Message> GetMessagesById(string username)
{
return db.Messages.Where(p => p.user == username).ToList();
}
}
and then:
public class FooController: Controller
{
public ActionResult Index()
{
var db = new MessagesRepository()
ViewBag.messages = db.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString());
return View();
}
}
public class BarController: Controller
{
public ActionResult Index()
{
var db = new MessagesRepository()
ViewBag.messages = db.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString());
return View();
}
}
OK, that's the first step. This code could be improved by decoupling the controllers from the repository by introducing an abstraction for this repository:
public interface IMessagesRepository
{
List<Message> GetMessagesById(string username);
}
public class MessagesRepository: IMessagesRepository
{
public List<Message> GetMessagesById(string username)
{
return db.Messages.Where(p => p.user == username).ToList();
}
}
then you could use constructor injection for those controllers:
public class FooController: Controller
{
private readonly IMessagesRepository _repository;
public class FooController(IMessagesRepository repository)
{
_repository = repository;
}
public ActionResult Index()
{
ViewBag.messages = _repository.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString());
return View();
}
}
public class BarController: Controller
{
private readonly IMessagesRepository _repository;
public class BarController(IMessagesRepository repository)
{
_repository = repository;
}
public ActionResult Index()
{
ViewBag.messages = _repository.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString());
return View();
}
}
finally you would configure your DI framework to pass the corresponding implementation into those controllers.
I would also recommend you replacing this ViewBag with a strongly typed view model:
public class MyViewModel
{
public List<Message> Messages { get; set; }
}
and then:
public ActionResult Index()
{
var model = new MyViewModel
{
Messages = _repository.GetMessagesById(Membership.GetUser().ProviderUserKey.ToString())
};
return View(model);
}
Place GetMessageById (and all other methods needed for accessing messages) to separate class and use the class everywhere you need to get Message data.
MessageService service = new MessageService();
ViewBag.messages = service.GetMessagesById(...);
I'm playing with the latest Entity Framework CTP 5 release and building a simple asp.net MVC blog where I just have two tables: Post and Comments. This is done entirely in POCO, I just need help on the DbContext part, where I need it to be unit testable (using IDbSet?) and I need a simple/generic repository pattern for add, update, delete, retrieval. Any help is appreciated.
Thanks.
Start with you DbContext, create a new file called Database.cs:
Database.cs
public class Database : DbContext
{
private IDbSet<Post> _posts;
public IDbSet<Post> Posts {
get { return _posts ?? (_posts = DbSet<Post>()); }
}
public virtual IDbSet<T> DbSet<T>() where T : class {
return Set<T>();
}
public virtual void Commit() {
base.SaveChanges();
}
}
Define a IDatabaseFactory and implement it with DatabaseFactory:
IDatabaseFactory.cs
public interface IDatabaseFactory : IDisposable
{
Database Get();
}
DatabaseFactory.cs
public class DatabaseFactory : Disposable, IDatabaseFactory {
private Database _database;
public Database Get() {
return _database ?? (_database = new Database());
}
protected override void DisposeCore() {
if (_database != null)
_database.Dispose();
}
}
Disposable extension method:
Disposable.cs
public class Disposable : IDisposable
{
private bool isDisposed;
~Disposable()
{
Dispose(false);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
private void Dispose(bool disposing)
{
if(!isDisposed && disposing)
{
DisposeCore();
}
isDisposed = true;
}
protected virtual void DisposeCore()
{
}
}
Now we can define our IRepository and our RepositoryBase
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> AllReadOnly();
}
RepositoryBase.cs
public abstract class RepositoryBase<T> where T : class
{
private Database _database;
private readonly IDbSet<T> _dbset;
protected RepositoryBase(IDatabaseFactory databaseFactory)
{
DatabaseFactory = databaseFactory;
_dbset = Database.Set<T>();
}
protected IDatabaseFactory DatabaseFactory
{
get; private set;
}
protected Database Database
{
get { return _database ?? (_database = DatabaseFactory.Get()); }
}
public virtual void Add(T entity)
{
_dbset.Add(entity);
}
public virtual void Delete(T entity)
{
_dbset.Remove(entity);
}
public virtual void Update(T entity)
{
_database.Entry(entity).State = EntityState.Modified;
}
public virtual T GetById(long id)
{
return _dbset.Find(id);
}
public virtual IEnumerable<T> All()
{
return _dbset.ToList();
}
public virtual IEnumerable<T> AllReadOnly()
{
return _dbset.AsNoTracking().ToList();
}
}
Now you can create your IPostRepository and PostRepository:
IPostRepository.cs
public interface IPostRepository : IRepository<Post>
{
//Add custom methods here if needed
Post ByTitle(string title);
}
PostRepository.cs
public class PostRepository : RepositoryBase<Post>, IPostRepository
{
public PostRepository(IDatabaseFactory databaseFactory) : base(databaseFactory)
{
}
public Post ByTitle(string title) {
return base.Database.Posts.Single(x => x.Title == title);
}
}
Lastly, the UoW:
IUnitOfWork.cs
public interface IUnitOfWork
{
void Commit();
}
UnitOfWork.cs
private readonly IDatabaseFactory _databaseFactory;
private Database _database;
public UnitOfWork(IDatabaseFactory databaseFactory)
{
_databaseFactory = databaseFactory;
}
protected Database Database
{
get { return _database ?? (_database = _databaseFactory.Get()); }
}
public void Commit()
{
Database.Commit();
}
Using in your controller:
private readonly IPostRepository _postRepository;
private readonly IUnitOfWork_unitOfWork;
public PostController(IPostRepository postRepository, IUnitOfWork unitOfWork)
{
_postRepository = postRepository;
_unitOfWork = unitOfWork;
}
public ActionResult Add(Post post) {
_postRepository.Add(post);
_unitOfWork.Commit();
}
You will need to use an IoC container like StructureMap to make this work. You can install structure map via NuGet, or if you are using MVC 3, you can install the StructureMap-MVC NuGet package. (Links Below)
Install-Package StructureMap.MVC4
Install-Package StructureMap.MVC3
Install-Package Structuremap
If you have questions just let me know. Hope it helps.
I just love this in-depth article about Entity Framework 4 POCO, Repository and Specification Pattern
http://huyrua.wordpress.com/2010/07/13/entity-framework-4-poco-repository-and-specification-pattern/
The only thing I'd do differently is in the implementation, i.e. expose the IPostRepository in the service layer and have an interface field of type IPostService in the controller just as another layer of abstraction but otherwise this is a good example - nice one, Paul.