I am using Autofac for IoC
Here is my container initiator class, which the responsibility is to register the dependencies.
public class ContainerInit
{
public static IContainer BuildContainer()
{
var conFac = new ContainerFactory();
var builder = new ContainerBuilder();
builder.Register(conFac).As<IContainerFactory>().SingleInstance();
builder.Register(c=> new MainClass(conFac)).As<IMainClass>().SingleInstance();
builder.Register(c=> new Database(conFac)).As<IDatabase>().SingleInstance();
var logger = LoggUtil.CreateLogger();
builder.Register(logger).As<ILogger>().SingleInstance();
var container = builder.Build();
ContainerFactory.SetContainer(container);
return container;
}
}
Problem with this approach is, I need to pass IContainerFactory to the constructor of every class I use in my application as follow
public class MainClass: IMainClass
{
private readonly ILogger _logger;
private readonly IDatabase _db;
public MainClass(IContainerFactory containerFactory)
{
_logger = containerFactory.GetInstance<ILogger>();
_db = containerFactory.GetInstance<IDatabase>(); //example
}
public AddDetails(Data data)
{
//do some business operations
_db.Add(data);
_logger.Information("added");
}
}
So it is difficult to unit test these classes.
How can come up with a good solution?
A better approach would be to pass the dependencies you need in your class into your constructor:
public class MainClass : IMainClass
{
private readonly ILogger _logger;
private readonly IDatabase _db;
public MainClass(ILogger logger, IDatabase db)
{
_logger = logger;
_db = db;
}
public void AddDetails(Data data)
{
//do some business operations
_db.Add(data);
_logger.Information("added");
}
}
Then you could use a mocking framework such as Moq to mock your class dependencies and perform verifications on whether the dependencies were called:
[TestClass]
public class UnitTest1
{
private Mock<ILogger> _mockLogger = new Mock<ILogger>();
private Mock<IDatabase> _mockDb = new Mock<IDatabase>();
[TestMethod]
public void TestMethod1()
{
// arrange
var mainClass = new MainClass(_mockLogger.Object, _mockDb.Object);
var data = new Data();
// act
mainClass.AddDetails(data);
// assert
_mockDb
.Verify(v => v.Add(data), Times.Once);
}
}
I would not verify your log message though as this could change and make the test brittle. Only verify functionality which is essential to doing what the method is intended for.
Your current Service Locator Anti-Pattern is what makes your code difficult to test in isolation as well as makes the class misleading about what it actually depends on.
MainClass should be refactored to follow Explicit Dependencies Principle
public class MainClass : IMainClass
private readonly ILogger logger;
private readonly IDatabase db;
public MainClass(ILogger logger, IDatabase db) {
this.logger = logger;
this.db = db;
}
public void AddDetails(Data data) {
//do some business operations
db.Add(data);
logger.Information("added");
}
}
The same pattern should also be followed for any other class you have that depends on the container factory, like Database.
You would however need to also refactor the container registration accordingly
public class ContainerInit {
public static IContainer BuildContainer() {
var builder = new ContainerBuilder();
builder.RegisterType<MainClass>().As<IMainClass>().SingleInstance();
builder.RegisterType<Database>().As<IDatabase>().SingleInstance();
var logger = LoggUtil.CreateLogger();
builder.Register(logger).As<ILogger>().SingleInstance();
var container = builder.Build();
return container;
}
}
Testing MainClass would required you to mock only the necessary dependencies of the class under test.
[TestClass]
public class MainClassTests {
[TestMethod]
public void Should_AddDetails_To_Database() {
// Arrange
var mockDb = new Mock<IDatabase>();
var data = new Data();
var mainClass = new MainClass(Mock.Of<ILogger>(), mockDb.Object);
// Act
mainClass.AddDetails(data);
// Assert
mockDb.Verify(_ => _.Add(data), Times.Once);
}
}
Here I would like to share solution, which I use in my project
To do unit testing of particular function, I use below structure
[TestClass]
public class TestSomeFunction
{
public IComponentContext ComponentContext { get; set; }
[TestInitialize]
public void Initialize()
{
//Registering all dependencies required for unit testing
this.ComponentContext = builder.Build(); //You have not build your container in your question
}
[TestMethod]
public void Testfunction()
{
//Resolve perticular dependency
var _logger = containerFactory.Resolve<ILogger>();
//Test my function
//use _logger
}
}
Related
tl;dr;
How can I inject the IDbContext factory in a Integration XUnit test?
I´m working on a Blazor Server project and I am creating a service that uses IDbContextFactory instead of the normal DbContext. The service uses EntityFrameworkCore to communicate with the DB. I need to create integration tests for this service that use the real test database, so I won´t Moq the factory.
This is the basic structure of my service.
public class CatalogService<T> : IEntityService<T> where T : CatalogBase
{
private readonly IDbContextFactory<ApplicationDbContext> _contextFactory;
private readonly ILogger<T> _logger;
//The factory is injected via constructor
public CatalogService(IDbContextFactory<ApplicationDbContext> contextFactory, ILogger<T> logger)
{
_contextFactory = contextFactory;
_logger = logger;
}
//... All the functions
}
I also have a fixture where some seed data can be created
public class TestDatabaseFixture
{
private const string ConnectionString = #"my_connection";
private static readonly object _lock = new();
private static bool _databaseInitialized;
public TestDatabaseFixture()
{
lock (_lock)
{
if (!_databaseInitialized)
{
using (var context = CreateContext())
{
context.Database.EnsureDeleted();
context.Database.EnsureCreated();
//Create Seed Data for Brands
for (int i = 0; i < 100; i++) {
context.PcMarcas.Add(new PcBrand { Description = $"Brand {(i + 1).ToString("0000") }" });
}
context.SaveChanges();
}
_databaseInitialized = true;
}
}
}
public ApplicationDbContext CreateContext()
{
return new ApplicationDbContext(
new DbContextOptionsBuilder<ApplicationDbContext>()
.UseSqlServer(ConnectionString)
.Options);
}
public IDbContextFactory<ApplicationDbContext> CreateDbContextFactory() {
//How do I return the context factory? <---
}
}
I know how to moq my logger and create a normal DBContext, but I´m not sure how to inject the factory in the test
[Fact]
public async Task GetAsync_ShouldReturnAnItem()
{
//Setup ------------------------------------------------------
var contextFactory = Fixture.CreateDbContextFactory(); //from the fixture
var logger = Mock.Of<ILogger<PcMarca>>();
var service = new CatalogService<PcMarca>(contextFactory, logger);
//Act -------------------------------------------------------
//Assert ----------------------------------------------------
}
You'll need to implement a IDbContextFactory<ApplicationDbContext> yourself.
To reuse your existing code to create an ApplicationDbContext instance, you can choose to implement that IDbContextFactory<ApplicationDbContext> as an inner class of your TestDatabaseFixture.
For brevity below code doesn't include the constructor.
public class TestDatabaseFixture
{
public class ApplicationDbContextFactory : IDbContextFactory<ApplicationDbContext>
{
public ApplicationDbContext CreateDbContext()
{
return CreateApplicationDbContext();
}
}
private const string ConnectionString = #"my_connection";
public ApplicationDbContext CreateContext()
{
return CreateApplicationDbContext();
}
public IDbContextFactory<ApplicationDbContext> CreateDbContextFactory()
{
return new ApplicationDbContextFactory();
}
private static ApplicationDbContext CreateApplicationDbContext()
{
return new ApplicationDbContext(
new DbContextOptionsBuilder<ApplicationDbContext>()
.UseSqlServer(ConnectionString)
.Options);
}
}
I have StrategyName set in appsettings.json which represents the name of the strategy class. I need to get an instance of it.
ITradingStrategy _tradingStrategy = StrategyUtils.GetStrategyInstance(logger, _tradeOptions.StrategyName)
which is equal to
ITradingStrategy _tradingStrategy = new RsiStrategy(logger);
Is it possible to be made in a better way? It works but looks ugly. Since we know the strategy name in the beginning (from appsettings.json), there should probably be a way to obtain it in a better ASP.NET Core way. Maybe some cool extension method, I don't know.
appsettings.json
{
"TradeConfiguration": {
"StrategyName": "RsiStrategy",
...
}
}
Code
public class LiveTradeManager : ITradeManager
{
private readonly ILogger _logger;
private readonly IExchangeClient _exchangeClient;
private readonly ITradingStrategy _tradingStrategy;
private readonly ExchangeOptions _exchangeOptions;
private readonly TradeOptions _tradeOptions;
public LiveTradeManager(ILogger logger, IConfiguration configuration, IExchangeClient exchangeClient)
{
_logger = logger;
_exchangeClient = exchangeClient;
_exchangeOptions = configuration.GetSection("ExchangeConfiguration").Get<ExchangeOptions>();
_tradeOptions = configuration.GetSection("TradeConfiguration").Get<TradeOptions>();
_tradingStrategy = StrategyUtils.GetStrategyInstance(logger, _tradeOptions.StrategyName); // This is the questioned line
}
}
public static ITradingStrategy GetStrategyInstance(ILogger logger, string strategyName)
{
var strategyType = Assembly.GetAssembly(typeof(StrategyBase))
.GetTypes().FirstOrDefault(type => type.IsSubclassOf(typeof(StrategyBase)) && type.Name.Equals(strategyName));
if (strategyType == null)
{
throw new ArgumentException($"The strategy \"{strategyName}\" could not be found.", nameof(strategyName));
}
var strategy = Activator.CreateInstance(strategyType, logger) as ITradingStrategy;
return strategy;
}
// Strategies
public interface ITradingStrategy
{
IReadOnlyList<TradeAdvice> Prepare(IReadOnlyList<OHLCV> candles);
}
public abstract class StrategyBase : ITradingStrategy
{
private readonly ILogger _logger;
protected StrategyBase(ILogger logger)
{
_logger = logger;
}
public abstract IReadOnlyList<TradeAdvice> Prepare(IReadOnlyList<OHLCV> candles);
}
public class RsiStrategy : StrategyBase
{
private readonly ILogger _logger;
public RsiStrategy(ILogger logger) : base(logger)
{
_logger = logger;
}
public override IReadOnlyList<TradeAdvice> Prepare(IReadOnlyList<OHLCV> candles)
{
... _logger.Information("Test");
}
}
// Main
public class Program
{
public static void Main(string[] args)
{
CreateHostBuilder(args).Build().Run();
}
public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureAppConfiguration((hostingContext, config) =>
{
config
.AddJsonFile("appsettings.json")
.AddEnvironmentVariables();
})
.ConfigureServices((hostingContext, services) =>
{
services.AddSingleton(
Log.Logger = new LoggerConfiguration()
.ReadFrom.Configuration(hostingContext.Configuration)
.CreateLogger());
services.AddSingleton<ITradeManager, LiveTradeManager>();
services.AddSingleton<IExchangeClient, BinanceSpotClient>();
services.AddHostedService<LifetimeEventsHostedService>();
})
.UseSerilog();
}
Your problem can be solved multiple ways and using reflection would be the last one.
From your problem statement, I figure that you have multiple strategy classed implementing ITradingStrategy interface, and you configuration value from appsettings.json file decides which strategy to use.
One of the approach you can use here is to use factory to initialize appropriate strategy class based on the configuration value.
Following is the factory class and interface which will create Strategy class object based on the strategy name passed to it.
public interface IStrategyFactory
{
ITradingStrategy GetStrategy(string strategyName);
}
public class StrategyFactory : IStrategyFactory
{
private IServiceProvider _serviceProvider;
public StrategyFactory(IServiceProvider serviceProvider)
{
_serviceProvider = serviceProvider;
}
public ITradingStrategy GetStrategy(string strategyName)
{
switch (strategyName)
{
case "Rsi":
// Resolve RsiStrategy object from the serviceProvider.
return _serviceProvider.GetService<RsiStrategy>();
case "Dmi":
// Resolve DmiStrategy object from the serviceProvider.
return _serviceProvider.GetService<DmiStrategy>();
default:
return null;
}
}
}
This strategy can now be used in controller and call its GetStrategy method by passing the strategy name which in-turn is retrieved from the configuration.
public class HomeController : Controller
{
private readonly ILogger<HomeController> _logger;
// Strategy factory.
private IStrategyFactory _strategyFactory;
// Configuration
private IConfiguration _configuration;
public HomeController(ILogger<HomeController> logger, IConfiguration configuration, IStrategyFactory strategyFactory)
{
_logger = logger;
_strategyFactory = strategyFactory;
_configuration = configuration;
}
public IActionResult Index()
{
// Get Configuration value "StrategyName" from configuration.
// In your case this will be your own custom configuration.
var strategyName = _configuration.GetValue<string>("StrategyName");
// Pass strategyName to GetStrategy Method.
var strategy = _strategyFactory.GetStrategy(strategyName);
// Call Prepare method on the retrieved strategy object.
ViewBag.PreparedList = strategy.Prepare(new List<OHLCV>());
return View();
}
}
For the above code to work you need to register strategy classed in to serviceCollection.
services.AddSingleton<RsiStrategy>();
services.AddSingleton<DmiStrategy>();
And also the StrategyFactory.
services.AddSingleton<IStrategyFactory, StrategyFactory>();
EDIT
Based on your comment below, you need to be able to resolve the strategy types without additional overhead of registering them in DI as when new types are created and also without making changes in the factory.
You need to use reflection for this. Using reflection you can determine the types which you want to register in the DI. As following.
//Get all the types which are inheriting from StrategyBase class from the assembly.
var strategyTypes = Assembly.GetAssembly(typeof(StrategyBase))
?.GetTypes()
.Where(type => type.IsSubclassOf(typeof(StrategyBase)));
if (strategyTypes != null)
{
//Loop thru the types collection and register them in serviceCollection.
foreach (var type in strategyTypes)
{
services.Add(new ServiceDescriptor(typeof(StrategyBase), type, ServiceLifetime.Singleton));
}
}
With the above code, all the types which are inheriting from StrategyBase are registered in serviceCollection. Now using serivceProvider we can get all the registered instances and look for the instance which has correct strategyName.
So the factory's GetStrategy method will look like as following.
public ITradingStrategy GetStrategy(string strategyName)
{
var strategies = _serviceProvider.GetServices<StrategyBase>();
var strategy = strategies.FirstOrDefault(s => s.GetType().Name == strategyName);
if (strategy == null)
{
throw new ArgumentException($"The strategy \"{strategyName}\" could not be found.", nameof(strategyName));
}
return strategy;
}
I hope this will help you resolve your issue.
I've created an injectable dbcontext
Startup.cs:
public void ConfigureServices(IServiceCollection services) {
services.AddScoped<IUnitOfWork, UnitOfWork>();
services.AddDbContext<DBContext>(options => options.UseSqlServer("Server=localhost;Database=mydb;Trusted_Connection=True;"));
}
UnitOfWork:
public class UnitOfWork : IUnitOfWork {
private readonly DBContext _context;
public UnitOfWork(DBContext context) {
_context = context;
}
The injection working fine in the controller:
public class UserController : ControllerBase {
private readonly IUnitOfWork unitOfWork;
public UserController(IUnitOfWork unitOfWork) {
this.unitOfWork = unitOfWork;
}
}
How can I create custom class that takes IUnitOfWork in the constructor and call it from main program?
CustomClass :
public class CustomClass {
private readonly IUnitOfWork unitOfWork;
public CustomClass(IUnitOfWork unitOfWork) {
this.unitOfWork = unitOfWork;
}
}
Main program:
public class Program {
public static void Main(string[] args) {
var unitOfWork=new UnitOfWork() // Here I don't want to pass new DBContext I want to reach the same injected DBContext
var customClass =new CustomClass (unitOfWork);
}
}
Firstly, move out your code from ConfigureServices to some shared library that can be used both by Web and Console project. Create extension method to configure all your services.
using Microsoft.Extensions.DependencyInjection;
namespace ConsoleApp13
{
public static class ConfigureServicesExtensions
{
public static void ConfigureMyServices(this IServiceCollection serviceCollection)
{
serviceCollection.AddDbContext<ApplicationDbContext>();
serviceCollection.AddScoped<IUnitOfWork, UnitOfWork>();
serviceCollection.AddScoped<CustomClass>();
}
}
}
This is how your Console app will look like
using Microsoft.Extensions.DependencyInjection;
namespace ConsoleApp13
{
class Program
{
static void Main(string[] args)
{
var serviceCollection = new ServiceCollection();
serviceCollection.ConfigureMyServices();
using var serviceProvider = serviceCollection.BuildServiceProvider();
using var scope = serviceProvider.CreateScope();
var myService = scope.ServiceProvider.GetService<CustomClass>();
}
}
}
And your web project
public void ConfigureServices(IServiceCollection services)
{
services.ConfigureMyServices();
}
What you can do is just add your class to the dependecy injection container and inject it into your constructor, you wouldn't need to inject the IUnitOfWork in you controller.
services.AddScoped<CustomClass>();
and then in your constroller constructor
public class UserController : ControllerBase {
private readonly CustomClass _CustomClass;
public UserController(CustomClass customClass) {
_CustomClass = customClass;
}
}
after that you are able to use this class in your class methods
I would try something like this:
public class Program {
public static void Main(string[] args) {
var optionsBuilder = new DbContextOptionsBuilder<DbContext>();
optionsBuilder.UseSqlServer(connectionstring);
using(DbContext dbContext = new DbContext(optionsBuilder.Options))
{
var unitOfWork=new UnitOfWork(dbContext)
var customClass =new CustomClass (unitOfWork);
.....
}
}
}
I have a WebApi done in Core.net 2.0, with UOW , and automapper.
Everything is working fine, but now I want to implement Unit Test with Nunit, and I have this error of automapper
Message: System.InvalidOperationException : Mapper not initialized.
Call Initialize with appropriate configuration. If you are trying to
use mapper instances through a container or otherwise, make sure you
do not have any calls to the static Mapper.Map methods, and if you're
using ProjectTo or UseAsDataSource extension methods, make sure you
pass in the appropriate IConfigurationProvider instance.
How can I solve this. Thanks in advance .
Jolynice
Class AutoMapperProfile.cs
public class AutoMapperProfile : Profile
{
public AutoMapperProfile()
{
CreateMap<Cars, CarsDTO>()
.ReverseMap();
}
}
class Startup.cs
public class Startup
{
public IConfiguration Configuration { get; }
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public void ConfigureServices(IServiceCollection services)
{
//removed configurations
// Add cors
services.AddCors();
// Add framework services.
services.AddMvc();
Mapper.Initialize(cfg =>
{
cfg.AddProfile<AutoMapperProfile>();
});
// Repositories
services.AddScoped<IUnitOfWork, HttpUnitOfWork>();
services.AddScoped<IAccountManager, AccountManager>();
}
}
class carsController.cs
[Authorize]
[Route("api/[controller]")]
public class CarsController : Controller
{
private IUnitOfWork _unitOfWork;
readonly ILogger _logger;
private readonly IAccountManager _accountManager;
public CarsController(
IUnitOfWork unitOfWork,
ILogger<CarsController> logger,
IAccountManager accountManager)
{
_unitOfWork = unitOfWork;
_logger = logger;
_accountManager = accountManager;
}
[HttpGet]
public IActionResult GetAll()
{
var allCars = _unitOfWork.CarsRepository.GetAllCarsData();
if (allCars == null)
{
return NotFound();
}
return Ok(Mapper.Map<IEnumerable<CarsDTO>>(allCars));
}
and this is my unit test
[TestFixture]
public class CarsControllerTest
{
#region private variables
List<Cars> cars = new List<Cars>();
CarsController _carsController = null;
IUnitOfWork _unitOfWork;
ICarsRepository _carsRepository;
#endregion
[SetUp]
public void SetUp()
{
cars = new List<Cars>
{
new Cars
{
Alias = "406Moq",
BrandId = 1,
ModelId = 1,
Plate = "00-00-01",
AltranVehicle = 0,
DefaultCar = 0,
Active = 1,
ColorId = 1
}
};
}
[Test]
public void GetAllCarsControllerTest()
{
//Arrange
_carsRepository = SetupCarsRepository();
var unityOfWork = new Mock<IUnitOfWork>();
var _logger = new Mock<ILogger<CarsController>>();
var accountManager = new Mock<IAccountManager>();
unityOfWork.SetupGet(c => c.CarsRepository).Returns(_carsRepository);
_unitOfWork = unityOfWork.Object;
_carsController = new CarsController(_unitOfWork, _logger.Object, accountManager.Object);
//Act
var carsResult = _carsController.GetAll();
//Assert
carsResult.StatusCode.Should().Be(HttpStatusCode.OK);
}
private ICarsRepository SetupCarsRepository()
{
//initialize repository
var mockRepo = new Mock<ICarsRepository>(MockBehavior.Default);
//Setup mocking behavior
mockRepo.Setup(c => c.GetAllCarsData()).Returns(cars);
return mockRepo.Object;
}
//Cleanup
[TearDown]
public void TearDown()
{
cars = null;
}
}
}
You are missing initialization of your mapper in your unit test. The following initializes the mapper in the CarsControllerTest class constructor.
[TestFixture]
public class CarsControllerTest
{
public CarsControllerTest()
{
Mapper.Initialize(cfg =>
{
cfg.AddProfile<AutoMapperProfile>();
});
}
}
I have a console application that Autofac DI is used to inject data and service layer from web application project.
here is the setup on console application:
public static class ContainerConfig
{
public static IContainer Configure()
{
var builder = new ContainerBuilder();
builder.RegisterType<DbFactory>().As<IDbFactory>();
builder.RegisterType<UnitOfWork>().As<IUnitOfWork>();
builder.RegisterType<Application>().As<IApplication>();
builder.RegisterType<DataRepository>().As<IDataRepository>();
builder.RegisterType<DataService>().As<IDataService>();
return builder.Build();
}
}
public interface IApplication
{
void Run();
}
public class Application : IApplication
{
private readonly IDataService _dataService;
public Application(IDataService dataService)
{
_dataService = dataService;
}
public void Run()
{
var data = _dataService.GetDataById(1);
var task = new TestTask("test");
data.AddTask(task);
_dataService.Update(data);
_dataService.SaveChanges();
}
}
main Program class:
class Program
{
static void Main(string[] args)
{
var container = ContainerConfig.Configure();
using (var scope = container.BeginLifetimeScope())
{
var app = scope.Resolve<IApplication>();
app.Run();
}
}
}
When the application is run loading the data works fine. However, saving a new entry does not seem to do the work.
However, when I remove DI and use simple class initializing in the Run method as below the save works fine:
IDbFactory dbFactory = new DbFactory();
IDataRepository dataRepository = new DataRepository(dbFactory);
var unitOfWork = new UnitOfWork(dbFactory);
IDataService service = new DataService(dataRepository, unitOfWork);
var data = service.GetDataById(1);
var task = new TestTask("test");
data.AddTask(task);
service.Update(data);
service.SaveChanges();
Am I missing something while I setup the autofac? It seems to access the data fine but when it comes to save it does not save the data. I debugged to see any issue but the program runs fine with no error. How can I debug this sort of issues to find more details?
Updated
public interface IDataService
{
void Add(TestTask task);
void SaveChanges();
}
public class DataService : IDataService
{
private readonly IDataRepository _dataRepository;
private readonly IUnitOfWork _unitOfWork;
public DataService(IDataRepository dataRepository, IUnitOfWork unitOfWork)
{
_dataRepository = dataRepository;
_unitOfWork = unitOfWork;
}
public void Add(TestTask task)
{
_dataRepository.Add(task);
}
public void SaveChanges()
{
_unitOfWork.Commit();
}
}
public class UnitOfWork : IUnitOfWork
{
private readonly IDbFactory _dbFactory;
private ApplicationDbContext _dbContext;
public UnitOfWork(IDbFactory dbFactory)
{
this._dbFactory = dbFactory;
}
public ApplicationDbContext DbContext => _dbContext ?? (_dbContext = _dbFactory.Init());
public void Commit()
{
DbContext.Commit();
}
}
After reading autofac scopes here
I found out that default scope is Instance Per Dependency. Which means that a unique instance will be returned from each request for a service. DbFactory should be for InstancePerLifetimeScope.
So changing configuration below fixes the issue:
public static class ContainerConfig
{
public static IContainer Configure()
{
var builder = new ContainerBuilder();
builder.RegisterType<DbFactory>().As<IDbFactory>().InstancePerLifetimeScope();
builder.RegisterType<UnitOfWork>().As<IUnitOfWork>();
builder.RegisterType<Application>().As<IApplication>();
builder.RegisterType<DataRepository>().As<IDataRepository>();
builder.RegisterType<DataService>().As<IDataService>();
return builder.Build();
}
}