Resolving dependencies in Integration test in ASP.NET Core - asp.net-core

I have ASP.NET Core API. I have already gone through documentation here that shows how to do integration testing in asp.net core. The example sets up a test server and then invoke controller method.
However I want to test a particular class method directly (not a controller method)? For example:
public class MyService : IMyService
{
private readonly DbContext _dbContext;
public MyService(DbContext dbContext)
{
_dbContext = dbContext;
}
public void DoSomething()
{
//do something here
}
}
When the test starts I want startup.cs to be called so all the dependencies will get register. (like dbcontext) but I am not sure in integration test how do I resolve IMyService?
Note: The reason I want to test DoSomething() method directly because this method will not get invoked by any controller. I am using Hangfire inside this API for background processing. The Hangfire's background processing job will call DoSomething() method. So for integration test I want to avoid using Hangfire and just directly call DoSomething() method

You already have a TestServer when you run integration tests, from here you can easily access the application wide container. You can't access the RequestServices for obvious reason (it's only available in HttpContext, which is created once per request).
var testServer = new TestServer(new WebHostBuilder()
.UseStartup<Startup>()
.UseEnvironment("DevelopmentOrTestingOrWhateverElse"));
var myService = testServer.Host.Services.GetRequiredService<IMyService>();

Related

Instantiating IHubContext in ASP.NET Core

I am using SignalR on different places of my web project. In my Controllers and HostedService this seems to be working fine. Clients instantiate connections with my hub and I can communicate with them back using an IHubContext instance, injected in the constructor of every controller/hostedservice.
I am having another singleton, running in Background (No HosteService or BackgroundTask). This class is getting IHubContext injected in the constructor also. Still every time it gets called, it seems like this singleton is having a different instance of IHubContext, since this context has no clients/groups connected to it.
This class is being registered as this in the startup function:
services.AddSingleton<IServiceEventHandler<TourMonitorEvent>, TourMonitorEventHandler>();
To configure SignalR I am doing the following in ConfigureServices:
services.AddSignalR().AddNewtonsoftJsonProtocol();
and the following in configure:
app.UseEndpoints(endpoints =>
{
endpoints.MapHub<MyHubClass>("/hubEndpoint");
endpoints.MapControllers();
});
the IHubContext ist bein injected as following in both Controllers/Hostedservices and the singleton:
public class MySingleton : IHandler<SomeGenericClass>
{
private readonly IHubContext<MyHubClass> _hubContext;
public MySingleton(IHubContext<MyHubClass> hubContext)
{
_hubContext = hubContext;
}
}
Are Controllers/HosteService being instantiated differently than my Singleton, in a way that might affect IHubContext instantiation?
As said in the documentation:
Hubs are transient.
So since you Singleton is not a HostedService or a BackgroundTask, I would recomend to inject the hub using a DI.
private IHubContext<MyHubClass, IMyHubClass> MyHubClass
{
get
{
return this.serviceProvider.GetRequiredService<IHubContext<MyHubClass, IMyHubClass>>();
}
}
Try this and verify if the context now is as you expected.

.NET Core DI passing info of AddHttpContextAccessor to a service

In my solution I have projects for my API, my Web App and also have another project which includes services, that are getting some information from a database and formatting them, these are currently only used by this API, but these could be used by other API projects in the future.
My API have a couple controllers that are returning JSON data from the result returned by the services.
In some cases the services needs to call the API to process some information before calling the request to the database. Since I have dev/staging/prod environment with their own URL I don't want to hardcode the URLs in the services I want to use DI to get these dynamicaly depending on the context.
In the Startup.cs of my API I have added services.AddHttpContextAccessor(); in the ConfigureServices(IServiceCollection services) section to gain access to the current http context :
public void ConfigureServices(IServiceCollection services)
{
...
services.AddHttpContextAccessor();
...
}
With that I know I can now access the information directly into my controller which I tried and it worked :
public class DataController : ControllerBase
{
...
private readonly string _baseUrl;
public FeaturesController(...
,IHttpContextAccessor httpContextAccessor)
{
...
_baseUrl = UrlHelpers.ShowBaseURL(httpContextAccessor) ?? throw new ArgumentNullException(nameof(_baseUrl));
}
}
public static class UrlHelpers
{
public static string ShowBaseURL(IHttpContextAccessor httpcontextaccessor)
{
var request = httpcontextaccessor.HttpContext.Request;
var absoluteUri = string.Concat(
request.Scheme,
"://",
request.Host.ToUriComponent(),
request.PathBase.ToUriComponent());
return absoluteUri;
}
}
I could do just about the same thing in the services but to me they should not act directly on the httpcontext, since this is not the job they are meant to do. I am sure I could do better by adding a class injected of some sort that would have then make the specific value available to my services.
I know I could also pass the _baseUrl directly as an argument when calling the services from my controller but since I am trying to better understand DI and use it I would rather find another way if it is viable.
I can't give credit but I went with Steven solution which make the most sens

How create a middleware with api endpoints in .NET Core

I have created the web application with the web api. The application contains some Controllers for example TodoController:
namespace TodoApi.Controllers
{
[Route("api/[controller]")]
public class TodoController : Controller
{
private readonly TodoContext _context;
public TodoController(TodoContext context)
{
_context = context;
}
[HttpGet]
public IEnumerable<TodoItem> GetAll()
{
return _context.TodoItems.ToList();
}
}
}
If I create the GET request - /api/todo - I get the list of Todos from database.
I have a list of controllers and api endpoints like above.
I would like distribute this api to another application ideally like middleware - my idea is register in Startup.cs like this:
public void ConfigureServices(IServiceCollection services)
{
services.AddTodoApi();
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
app.UseTodoApi();
}
This will be awesome use case for my api but I don't know how this controllers api endpoints rewrite like middleware and return same JSON data same approache like using classic Controllers.
How can I write the middleware in .NET Core for creating API endpoints?
Instead of the separate middleware, you may configure the MVC middleware to discovery controllers from another assembly:
// using System.Reflection;
public void ConfigureServices(IServiceCollection services)
{
...
services
.AddMvc()
.AddApplicationPart(typeof(TodoController).GetTypeInfo().Assembly);
Controllers are part of MVC middleware, they are not a separate part of request pipeline (but this is what middlewares are). When you register the custom middleware, it by default invokes on each request and you have HttpContext context as an input parameter to work with/edit
Request/Response data. But ASP.NET Core provides Map* extensions that are used as a convention for branching the pipeline.
Map branches the request pipeline based on matches of the given request path. If the request path starts with the given path, the branch is executed.
Example:
private static void HandleMapTodo(IApplicationBuilder app)
{
app.Run(async context =>
{
await context.Response.WriteAsync("/api/todo was handled");
});
}
public void Configure(IApplicationBuilder app)
{
app.Map("/api/todo", HandleMapTodo);
}
Note, that as middleware knows nothing about MVC middleware, you have only access to "raw" request and do not have features like model binding or MVC action filters.
Because it looks like the perfect microservices approach (similar than what my team is doing right now) I'd create a client assembly that can consume your API, the one that contains your TodoController, if you define a contract, and interface, for that API you can register it in your other assembly as it was a midleware and also you could mock that behaviour in your unit tests.
So, as I said, you could inject your client in ConfigureServices method, you can create:
public static IServiceCollection AddTodoRestClient(this IServiceCollection services)
{
services.AddSingleton<ITodoRestClient, TodoRestClient>();
return services;
}
Also consider that you will need to provide the enpoint so, it might looks like:
public static IServiceCollection AddConfiguredTodoClient(this IServiceCollection services, string todoEndpoint)
{
AddTodoClient(services);
ITodoRestClient todoRestClient = services.BuildServiceProvider().GetService<ITodoRestClient>();
// Imagine you have a configure method...
todoRestClient.Configure(services, todoEndpoint);
return services;
}
You can create those methods in a TodoRestClientInjector class and use them in Configure method on your startup.
I hope it helps
--- MORE DETAILS TO ANSWER COMMENTS ---
For me TodoClient is a Rest client library that implements calls to the ToDo API, (I've edited previous code to be TodoRestClient) methos like, i.e., CreateTodoItem(TodoDto todoItem) which implementation would call to the TodoController.Post([FromBody] item) or GetTodos() which wuold call TodoController.Get() and so on and so forth....
Regarding the enpoints... This approach implies to have (at least) two different applications (.NET Core apps), on the one hand the ASP NET Core app that has your TodoController and on the other hand a console application or another ASP NET Core API on which startup class you'll do the inyection adn the Rest client (the Todo Rest client) configuration ...
In a microservices approach using docker, in a dev environment, you'll use docker-compose-yml, but in a traditional approach you'll use concrete ports to define the endpoints...
So, imagine that you have in the second service a controller that need to use TodoController, to achieve so I'll use the above aproach and the "SecondController" would look like:
public class SecondController : Controller
{
private readonly SecondContext _context;
private readonly TodoRestClient _todoRestClient;
public TodoController(SecondContext context, ITodoRestClient todoRestClient)
{
_context = context;
_todoRestClient= todoRestClient;
}
// Whatever logic in this second controller... but the usage would be like:
_todoRestClient.GetTodos()
}
Just few final hints: it's key to minimize calls between services because it increases latency, and more and more if this happens on cascade. Also consider Docker usage, looks challenging but it is quite easy to start and, indeed, is thought to be used in scenarios that the one you presented and solutions like mine.
Again, I hope it helps.
Juan

How to configure hangfire with unity?

I have ASP.NET Web API application. The application is using Unity as IoC container. The application is also using Hangfire and I am trying to configure Hangfire to use Unity.
So based on documentation i am using Hangfire.Unity which registers the unity container as a current job activator in Hangfire.
I have a class which has dependency on IBackgroundJobClient
public class MyService
{
private MyDBContext _dbContext = null;
private IBackgroundJobClient _backgroundJobClient = null;
public MyService(MyDbContext dbContext, IBackgroundJobClient backgroundJobClient)
{
_dbContext = dbContext;
_backgroundJobClient = backgroundJobClient;
}
}
However even after configuring Hangfire.Unity it could not create & pass instance of BackgroundJobClient
So i had to register every dependency of BackgroundJobClient with unity container.
Unity Registration
public class UnityConfig
{
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
public static void RegisterTypes(IUnityContainer container)
{
container.RegisterType<MyDbContext>(new HierarchicalLifetimeManager(), new InjectionFactory(x => new MyDbContext()));
// register hangfire dependencies
container.RegisterType<IBackgroundJobClient, BackgroundJobClient>();
container.RegisterType<JobStorage, SqlServerStorage>(new InjectionConstructor("HangfireConnectionString"));
container.RegisterType<IJobFilterProvider, JobFilterAttributeFilterProvider>(new InjectionConstructor(true));
container.RegisterType<IBackgroundJobFactory, BackgroundJobFactory>();
container.RegisterType<IRecurringJobManager, RecurringJobManager>();
container.RegisterType<IBackgroundJobStateChanger, BackgroundJobStateChanger>();
}
}
OWIN Startup
public class Startup
{
public void Configuration(IAppBuilder app)
{
var container = UnityConfig.GetConfiguredContainer();
Hangfire.GlobalConfiguration.Configuration.UseSqlServerStorage("HangfireConnectionString");
Hangfire.GlobalConfiguration.Configuration.UseUnityActivator(container);
// if i dont call UseSqlServerStorage() above then UseHangfireDashboard() method fails with exception
//JobStorage.Current property value has not been initialized. You must set it before using Hangfire Client or Server API.
app.UseHangfireDashboard();
app.UseHangfireServer();
RecurringJob.AddOrUpdate<MyService>(x => x.Prepare(), Cron.MinuteInterval(10));
}
}
Code is working with such configuration. However i have questions:
Is this the correct way of configuring Unity with Hangfire?
Why do i need to invoke Hangfire.GlobalConfiguration.Configuration.UseSqlServerStorage("HangfireConnectionString") in OWIN startup even though SqlServerStorage is already registered with Unity container as JobStorage?
If i dont invoke UseSqlServerStorage() method in OWIN startup then i get exception on app.UseHangfireDashboard() method.
JobStorage.Current property value has not been initialized. You must
set it before using Hangfire Client or Server API.
I believe there is a problem where you want to kick off Hangfire outside of the Unity ecosystem, but also want Unity to understand how to instantiate the appropriate Hangfire interfaces with the associated implementations. Since Hangfire itself doesn't use Unity, you will need to start up Hangfire with the appropriate configuration, such as the SQL Server connection string, and then use that configuration to inform Unity how to instantiate the Hangfire interfaces. I was able to solve this problem by setting the global Hangfire configuration for SQL and then use that same Hangfire static instance to set up Unity.
Here's example code where first you will see how I start the hangfire dashboard and server with a connection string:
public void Configuration(IAppBuilder app)
{
var configuration = new Configuration(); // whatever this is for you
GlobalConfiguration.Configuration.UseSqlServerStorage(
configuration.GetConnectionString());
GlobalConfiguration.Configuration.UseActivator(
new HangfireContainerActivator(UnityConfig.GetConfiguredContainer()));
app.UseHangfireDashboard("/hangfire", new DashboardOptions
{
Authorization = new[] {new HangfireAuthorizationFilter()}
});
app.UseHangfireServer();
}
As the second example, here's the configuration of Unity for Hangfire; notice how this code is using the static JobStorage Hangfire object to instantiate any requests for JobStorage.
public static void RegisterHangfire(IUnityContainer container)
{
container.RegisterType<JobStorage>(new InjectionFactory(c => JobStorage.Current));
container.RegisterType<IJobFilterProvider, JobFilterAttributeFilterProvider>(new InjectionConstructor(true));
container.RegisterType<IBackgroundJobFactory, BackgroundJobFactory>();
container.RegisterType<IRecurringJobManager, RecurringJobManager>();
container.RegisterType<IBackgroundJobClient, BackgroundJobClient>();
container.RegisterType<IBackgroundJobStateChanger, BackgroundJobStateChanger>();
}
I believe this approach gives you the best of both worlds where you only set up your SQL Server connection once and you do it early to kick off Hangfire, but then you use that instance to tell Unity how to behave.

SimpleInjector: Injection does not work with MVC 4 ASP.NET Web API

I have this setup:
public static void Initialize(ISessionFactory factory)
{
var container = new Container();
InitializeContainer(container, factory);
container.RegisterMvcControllers(
Assembly.GetExecutingAssembly());
container.RegisterMvcAttributeFilterProvider();
container.Verify();
DependencyResolver.SetResolver(
new SimpleInjectorDependencyResolver(container));
}
private static void InitializeContainer(
Container container, ISessionFactory factory)
{
container.RegisterPerWebRequest<ISession>(
() => factory.OpenSession(), true);
}
The Initialize method is called in Application_Start:
public class WebApiApplication : HttpApplication
{
protected void Application_Start()
{
SimpleInjectorInitializer.Initialize(
new NHibernateHelper(
Assembly.GetCallingAssembly(),
this.Server.MapPath("/"))
.SessionFactory);
AreaRegistration.RegisterAllAreas();
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
}
}
But when i try to call the controller action I get an ArgumentException:
Type 'PositionReportApi.Controllers.PositionsController' does not have
a default constructor
Stack trace:
at System.Linq.Expressions.Expression.New(Type type) at
System.Web.Http.Internal.TypeActivator.Create[TBase](Type
instanceType) at
System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage
request, HttpControllerDescriptor controllerDescriptor, Type
controllerType)
I can't register an ISession.
How do i register an ISession that is created by a factory?
From the stack trace I can see that you are using the new .NET 4.5 ASP.NET Web API and Simple Injector is not in the presented call graph. This probably means that you haven't configured the Simple Injector for use with the new Web API, which is a different registration than what you need for MVC (for some strange reason, and I sincerely hope they fix this in the final release). Since you didn't register a Simple Injector specific System.Web.Http.Dependencies.IDependencyResolver implementation to the Web API's GlobalConfiguration.Configuration.DependencyResolver, you'll get the default behavior, which will only work with default constructors.
Take a look at this Stackoverflow answer Does Simple Injector supports MVC 4 ASP.NET Web API? to see how to configure Simple Injector with the new ASP.NET Web API.
UPDATE
Note that you can get this exception even if you configured the DependencyResolver correctly, but when you didn't register register your Web API Controllers explicitly. This is caused by the way Web API is designed.
Always register your Controllers explicitly.