This is what I've got:
public interface INamed
{
string Name { get; }
}
public interface IService
{
}
public class Service : IService
{
}
public class ServiceUser
{
public ServiceUser(IEnumerable<Lazy<IService, INamed>> services)
{
var cnt = services.Count(); // Always 0.
}
}
var builder = new ContainerBuilder();
builder.Register(c => new Service())
.As<IService>()
.WithMetadata<INamed>(m => m.For(n => n.Name, "Test"));
builder.RegisterType<ServiceUser>();
var container = builder.Build();
var su = container.Resolve<ServiceUser>();
The collection of Lazy<IService, INamed> services in the ServiceUser ctor is always empty. Can you explain what I'm doing wrong? One thing I immediately don't understand is where the concrete implementation of INamed is coming from. I guess Autofac generates that internally? Please help clear things up for me.
Upgrade to the latest Autofac.
Related
I am facing issue of mapping. My solution is as below.
I have two projects
1. Azure Function (v1) project with Framework: .Net Framework 4.7.2
2. Class Library with Framework: .Net Framework 4.7.2
In 1st project i have an azure function which is triggering using Queue and call my function BeginBackup(CancellationToken token, DateTime.Now()) which exist in my concreate class.
I am calling my function as below from my Azure function.
DependencyContext.Instance.Locator.GetInstance<IBackupTableStorageService>().BeginBackup(cancellationToken, SystemTime.UtcNow());
My DependencyContext.cs class is below.
using ClassLibrary1.BackupTableStorage;
using CommonServiceLocator;
using StructureMap;
using System;
using System.Collections.Generic;
namespace AzureFunctionsProject.Functions
{
public interface IDependencyContext
{
IServiceLocator Locator { get; }
}
public class DependencyContext : IDependencyContext
{
private static volatile IDependencyContext _instance;
private static readonly object SyncRoot = new Object();
public static IDependencyContext Instance
{
get
{
if (_instance == null)
{
lock (SyncRoot)
{
if (_instance == null)
{
_instance = new DependencyContext();
}
}
}
return _instance;
}
set => _instance = value;
}
public IServiceLocator Locator { get; private set; }
public DependencyContext()
{
Build();
}
private void Build()
{
var registry = new Registry();//Registry is the class belongs to StructureMap.
var container = new Container();
var serviceLocatorProvider = new StructureMapServiceLocator(container);
ServiceLocator.SetLocatorProvider(() => serviceLocatorProvider);
Locator = serviceLocatorProvider;
// register the container itself
registry.For<IServiceLocator>().Use(ServiceLocator.Current);
// Apply the registry to the container
container.Configure(x =>
{
x.AddRegistry<Domain.Registry>();
x.AddRegistry(registry);
});
}
}
public class StructureMapServiceLocator : ServiceLocatorImplBase
{
private IContainer Container { get; set; }
public StructureMapServiceLocator(IContainer container)
{
Container = container;
}
protected override object DoGetInstance(Type serviceType, string key)
{
if (string.IsNullOrEmpty(key))
{
return Container.GetInstance(serviceType);
}
return Container.GetInstance(serviceType, key);
}
protected override IEnumerable<object> DoGetAllInstances(Type serviceType)
{
foreach (object obj in Container.GetAllInstances(serviceType))
{
yield return obj;
}
}
}
}
I have another Registery class which i have created which have mapping of my interface with my concrete class.
Registery.cs file is below.
namespace ClassLibrary1.Domain
{
public class Registry: StructureMap.Registry
{
public Registry()
{
// The Localization Service needs to be passed a function to record exceptions
For<ILocalizationService>().Use<LocalizationService>()
.Ctor<LocalizationService.LogException>().Is(context => CreateExceptionLogger(context));
For<ICloudStorageWrapper>().Use<CloudStorageWrapper>();
For<IBackupTableStorageService>().Use<BackupTableStorageService>();
}
private LocalizationService.LogException CreateExceptionLogger(IContext context)
{
return (ex, c, m) =>
{
var logger = context.GetInstance<ILogicalOperationsLogger>();
logger.ErrorException(m, ex);
};
}
}
}
Like wise i have my Interface and respected to concreate class which has the definition of my method BeginBackup(CancellationToken token, DateTime.Now());
I am getting exception in DoGetInstance method in DependencyContext.cs class.
I am new in IoC and dependency injection, please let me know what i am doing wrong, if anything required to make question more clear please let me know.
Try to move the registration for IServiceLocator into the configure action. You can also remove the Registry-object you created:
private void Build()
{
var container = new Container();
var serviceLocatorProvider = new StructureMapServiceLocator(container);
ServiceLocator.SetLocatorProvider(() => serviceLocatorProvider);
Locator = serviceLocatorProvider;
// Apply the registry to the container
container.Configure(x =>
{
// register the container itself
x.For<IServiceLocator>().Use(serviceLocatorProvider);
x.AddRegistry<Domain.Registry>();
});
}
I am using the following code in a unit test for the test setup:
var simpleEntity = new SimpleEntity();
var complexEntity = new ComplexEntity
{
JoinEntity1List = new List<JoinEntity1>
{
new JoinEntity1
{
JoinEntity2List = new List<JoinEntity2>
{
new JoinEntity2
{
SimpleEntity = simpleEntity
}
}
}
}
};
var anotherEntity = new AnotherEntity
{
ComplexEntity = complexEntity1
};
using (var context = databaseFixture.GetContext())
{
context.Add(anotherEntity);
await context.SaveChangesAsync();
}
When SaveChangesAsync is reached EF throws an ArgumentException with the following message:
An item with the same key has already been added. Key: 1
I'm using a fixture as well for the unit test class which populates the database with objects of the same types, though for this test I want this particular setup so I want to add these new entities to the in memory database. I've tried adding the entities on the DbSet (not the DbContext) and adding all three entities separatly to no avail. I can however add "simpleEntity" separately (because it is not added in the fixture) but EF complains as soon as I try to add "complexEntity" or "anotherEntity".
It seems like EF in memory database cannot handle several Add's over different instances of the context. Is there any workaround for this or am I doing something wrong in my setup?
The databaseFixture in this case is an instance of this class:
namespace Test.Shared.Fixture
{
using Data.Access;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
public class InMemoryDatabaseFixture : IDatabaseFixture
{
private readonly DbContextOptions<MyContext> contextOptions;
public InMemoryDatabaseFixture()
{
var serviceProvider = new ServiceCollection()
.AddEntityFrameworkInMemoryDatabase()
.BuildServiceProvider();
var builder = new DbContextOptionsBuilder<MyContext>();
builder.UseInMemoryDatabase()
.UseInternalServiceProvider(serviceProvider);
contextOptions = builder.Options;
}
public MyContext GetContext()
{
return new MyContext(contextOptions);
}
}
}
You can solve this problem by using Collection Fixtures so you can share this fixture across several test classes. This way you don't build you context several times and thus you won't get this exception:
Some information about collection Fixture
My own example:
[CollectionDefinition("Database collection")]
public class DatabaseCollection : ICollectionFixture<DatabaseFixture>
{ }
[Collection("Database collection")]
public class GetCitiesCmdHandlerTests : IClassFixture<MapperFixture>
{
private readonly TecCoreDbContext _context;
private readonly IMapper _mapper;
public GetCitiesCmdHandlerTests(DatabaseFixture dbFixture, MapperFixture mapFixture)
{
_context = dbFixture.Context;
_mapper = mapFixture.Mapper;
}
[Theory]
[MemberData(nameof(HandleTestData))]
public async void Handle_ShouldReturnCountries_AccordingToRequest(
GetCitiesCommand command,
int expectedCount)
{
(...)
}
public static readonly IEnumerable<object[]> HandleTestData
= new List<object[]>
{
(...)
};
}
}
Good luck,
Seb
My problem is that I want to use Func<> factory to resolve dependency. And in if I use ContainerBuilder Update() (I need it for mocking some services in integration tests), this factories still resolve outdated instances.
I created simple scenario to reproduce the problem:
class Program
{
static void Main(string[] args)
{
var containerBuilder = new ContainerBuilder();
containerBuilder.RegisterType<Test>().As<ITest>();
containerBuilder.RegisterType<Test1Factory>().As<ITestFactory>();
containerBuilder.RegisterType<TestConsumer>().AsSelf();
var container = containerBuilder.Build();
var tc1 = container.Resolve<TestConsumer>();
var cbupdater = new ContainerBuilder();
cbupdater.RegisterType<Test2>().As<ITest>();
cbupdater.RegisterType<Test2Factory>().As<ITestFactory>();
cbupdater.Update(container);
var tc2 = container.Resolve<TestConsumer>();
Console.ReadLine();
}
}
public interface ITest
{
int Id { get; set; }
}
public class Test : ITest
{
public Test()
{
Id = 1;
}
public int Id { get; set; }
}
public class Test2 : ITest
{
public Test2()
{
Id = 2;
}
public int Id { get; set; }
}
public interface ITestFactory
{
ITest Create();
}
public class Test1Factory : ITestFactory
{
public ITest Create()
{
return new Test();
}
}
public class Test2Factory : ITestFactory
{
public ITest Create()
{
return new Test2();
}
}
public class TestConsumer
{
public TestConsumer(Func<ITest> testFactory, ITest test, ITestFactory customFactory)
{
Console.WriteLine("factory: " + testFactory().Id);
Console.WriteLine("direct: " + test.Id);
Console.WriteLine("MyCustomFactory: " + customFactory.Create().Id);
Console.WriteLine("*************");
Console.WriteLine();
}
}
The output is:
factory: 1 direct: 1 MyCustomFactory: 1
factory: 1 direct: 2 MyCustomFactory: 2
Notice "factory: 1" in both cases.
Am I missing something or I have to create my cusom factory in this scenario?
P.S.
Autofac 3.5.2 or 4.0 beta 8-157
.net 4.5.1
That's by design unfortunately, the reasons, I don't know. Looking at the Autofac code gives you a better insight on how they register items with the same interface definition, in short, all registrations are maintained but the last registration wins (ref). Wait...that's not all, weirdly, for Fun<...>, you actually get them in order. You can easily test by changing the constructor of the TestConsumer class to:
public TestConsumer(Func<ITest> testFactory, IEnumerable<Func<ITest>> testFactories, IEnumerable<ITest> tests, ITest test, ITestFactory customFactory)
{
// ...
}
Note that you get all the Funcs and the ITest registration. You are simply lucky that resolving ITest directly resolves to Test2.
Now, having said all of the above, there is a way described here. You have to create a container without the registration you want to override, therefore:
/// <summary>
/// This has not been tested with all your requirements
/// </summary>
private static IContainer RemoveOldComponents(IContainer container)
{
var builder = new ContainerBuilder();
var components = container.ComponentRegistry.Registrations
.Where(cr => cr.Activator.LimitType != typeof(LifetimeScope))
.Where(cr => cr.Activator.LimitType != typeof(Func<ITest>));
foreach (var c in components)
{
builder.RegisterComponent(c);
}
foreach (var source in container.ComponentRegistry.Sources)
{
builder.RegisterSource(source);
}
return builder.Build();
}
And you can simply change your main method to the following:
static void Main(string[] args)
{
var containerBuilder = new ContainerBuilder();
containerBuilder.RegisterType<Test>().As<ITest>();
containerBuilder.RegisterType<Test1Factory>().As<ITestFactory>();
containerBuilder.RegisterType<TestConsumer>().AsSelf();
var container = containerBuilder.Build();
var tc1 = container.Resolve<TestConsumer>();
container = RemoveOldComponents(container);
var cbupdater = new ContainerBuilder();
cbupdater.RegisterType<Test2>().As<ITest>();
cbupdater.RegisterType<Test2Factory>().As<ITestFactory>();
cbupdater.Update(container);
var tc2 = container.Resolve<TestConsumer>();
Console.ReadLine();
}
PS: Wouldn't it be great to have a method which does the exact opposite of PreserveExistingDefaults()
Structuremap defines a 'BuildUp' method that takes an already-constructed object and performs setter injection to push in configured dependencies into that object.
Does Autofac have an equivalent method ?
The question was referring to already-constructed objects (ones not registered in the container) so the correct answer is either InjectProperties or InjectUnsetProperties.
The following test demonstrates the behaviour
public class TestPropertyInjection
{
public object ShouldBeInjectedByAutofac { get; set; }
}
[Fact]
public void Autofac_can_inject_properties()
{
var builder = new ContainerBuilder();
builder.RegisterType(typeof(object));
var container = builder.Build();
var existingObjectNotRegisteredInContainer = new TestPropertyInjection();
container.InjectProperties(existingObjectNotRegisteredInContainer);
// can also use InjectUnsetProperties to only set unset properties
//container.InjectUnsetProperties(existingObjectNotRegisteredInContainer);
Assert.NotNull(existingObjectNotRegisteredInContainer.ShouldBeInjectedByAutofac);
}
Try InjectUnsetProperties.
Sample:
public class YourModule : Module
{
protected override void Load(ContainerBuilder builder)
{
base.Load(builder);
builder.RegisterType<YourClass>().OnActivated(e => e.Context.InjectUnsetProperties(e.Instance));
}
}
In more recent versions of Autofac you can simply use:
builder.RegisterType<YourClass>().PropertiesAutowired();
I'm very new to Mocking. In the below example i'm using Moq and trying to create a _companyRepository. However the second test has a null ref. ie Company is not instantiated.
Assert.AreEqual(viewModel.Company.Name, "MyCompany");
Think i'm missing something silly here.
[TestClass]
public class ErrorControllerTest
{
private Mock<ICompanyRepository> _companyRepository;
public ErrorController CreateErrorController()
{
_companyRepository = new Mock<ICompanyRepository>();
_companyRepository.Setup(c => c.Get(2)).Returns(new Company {Name = "MyCompany"});
return new ErrorController(_companyRepository.Object);
}
[TestMethod]
public void Test()
{
var controller = CreateErrorController();
controller.Test(""); // action is called
var viewModel = (ErrorViewModel)controller.ViewData.Model;
Assert.IsInstanceOfType(controller.ViewData.Model, typeof(ErrorViewModel));
Assert.AreEqual(viewModel.Company.Name, "MyCompany");
}
}
controller
public class ErrorController : Controller
{
private readonly ICompanyRepository _companyRepository;
public ErrorController(ICompanyRepository companyRepository)
{
_companyRepository = companyRepository;
}
public ActionResult Test()
{
var company = _companyRepository.Get(2);
var viewModel = new ErrorViewModel
{
Company = company
};
return View(viewModel);
}
}
this works.... Guess i didn't compile everything. Very dumb.
Tho am i doing this the right way. Appreciate any comments.