Develop Reference

Mock HttpRequest in ASP.NET Core Controller

I'm building a Web API in ASP.NET Core, and I want to unit test the controllers.
I inject an interface for data access, that I can easily mock. But the controller has to check the headers in the Request for a token, and that Request doesn't seem to exist when I simply instantiate the controller myself, and it is also get-only, so I can't even manually set it. I found lots of examples to mock an ApiController, but that isn't .NET core. Also many tutorials and examples of how to unit test .net core controllers, but none actually used the HttpRequest.
I built an MCVE to demonstrate this:
[Produces("application/json")]
[Route("api/Players")]
public class PlayersController : Controller
{
private IAccessor accessor;
public PlayersController(IAccessor ac = null):base()
{
accessor = ac ?? AccessorFactory.GetAccessor();
}
/// <summary>
/// Get all players. Must be logged in.
/// </summary>
/// <returns>Ok or Unauthorized.</returns>
[HttpGet]
public IActionResult Get()
{
Player client = accessor.GetLoggedInPlayer(Request.Headers["token"]); // NRE here because Request is null
if (client == null) return Unauthorized();
return Ok(accessor.GetAllPlayers());
}
}
I'm using Moq and MSTest in my test project, and inject a mocked IAccessor. How do I inject the Request, or initialize it with the controller? I guess my last resort would be reflection, but I really want to avoid that.

When creating an instance of the controller under test, make sure to assign a HttpContext that contains the required dependencies for the test to be exercised to completion.
You could try mocking a HttpContext and providing that to the controller or just use DefaultHttpContext provided by the framework
//Arrange
var mockedAccessor = new Mock<IAccessor>();
//...setup mockedAccessor behavior
//...
var httpContext = new DefaultHttpContext(); // or mock a `HttpContext`
httpContext.Request.Headers["token"] = "fake_token_here"; //Set header
//Controller needs a controller context
var controllerContext = new ControllerContext() {
HttpContext = httpContext,
};
//assign context to controller
var controller = new PlayersController (mockedAccessor.Object){
ControllerContext = controllerContext,
};
//Act
var result = controller.Get();
//...
The above assumes you already know how to mock the controller dependencies like IAccessor and was meant to demonstrate how to provide framework specific dependencies needed for the test.

Setup Mocked ViewModel for Unit Testing

Here is the scenario:
I'm writing a test for my controller and need to setup a view model titled CheckoutViewModel. My controller method, Products does not take CheckoutViewModel as a parameter, so I cannot pass it in that way.
Currently, the test fails returning a Null Exception because CheckoutViewModel is not getting set and called.
Question: How can I setup my CheckoutViewModel with data.
Error Details:
System.NullReferenceException
Object reference not set to an instance of an object
Current Test
[TestMethod]
public void Products_ProductControllerIsCalled_ReturnsViewWithProducts()
{
// Arrange
var currentSession = _autoMoqer.GetMock<ICurrentSession>().Object;
ProductController productController = new ProductController(currentSession);
var checkoutViewModel = new CheckoutViewModel
{
CheckoutId = new Guid()
};
// Act
ActionResult result = productController.Products();
// Assert
Assert.IsInstanceOfType(result, typeof(ViewResult));
}
Controller
[AccectReadVerbs]
public ActionResult Products()
{
CheckoutViewModel checkoutViewModel = GetCheckoutViewModel();
var checkoutId = checkoutViewModel.CheckoutId;
var result = _productOrchestrator.Products(checkoutId, currentSession)
return View(result);
}
Failing on this method
private CheckoutViewModel GetCheckoutViewModel()
{
if(Session["CheckoutViewModel"] == null)
{
return new CheckoutViewModel();
}
return (CheckoutViewModel)Session["CheckoutViewModel"];
}

If GetCheckoutViewModel has some dependencies on i.e services, dbConnection or other complex classes, you need to add a class with an interface, move the method for GetCheckOutViewModel to the class and take the new interface as a dependency to the controller. Then you need to mock the new interface.
Or edit your viewmodel to take interface dependencies on the stuff that stands in the way of unit testing, i.e the Session.

I think you could create some interface:
public interface ISessionManager
{
Session session {get; set;}
}
Then your controller constructor:
public ProductsController(ISessionManager sm)
{
_sessionManager = sm;
}
Then you can pass a mocked instance to your controller.

I'm guessing that the exceptions is due to the fact that when you're running the unit test there will not be any (webserver) session available. What you want do is to isolate your tests from any external dependencies - and a session state that is part of the webserver hosting environment would be an external dependency.
To solve this you need to either mock or stub out the Session object from your test. There are many ways to do this, but the easiest way would be to make Session a public property on the Controller. From your test you would then set the Session to an instance you create within your test.

C# unit testing API 2 call

I have a web api 2 web service get method. Inside I'm using HttpContext.Current.Request.UserHostAddress. When calling my controller method directly int he unit test this isn't filled in so is errors with null object. So I searched for how to fill this in and found the following which helped with that issue: Add IP address to HttpRequestMessage
However, this needs a server name to send the request to. The problem is that when tests run the VSExpress will need to be running for this API web service, which it won't be when just running the tests. On top of that even if it was it seems it picks a random port to run on so I couldn't hardcode the address like he does in the above link. How can I test my api 2 method given the above issues?
This is the line that blows up when I just test the api method
string ip = HttpContext.Current.Request.UserHostAddress;
[EDIT] Answer
Just so everyone knows here is the solution in code
public class MyController : ApiController
{
private: HttpRequestBase httpRequest;
public MyController()
{
httpRequest = new HttpRequestWrapper(HttpContext.Current.Request)
}
public MyController(HttpRequestBase http)
{
httpRequest = http;
}
public HttpResponseMessage Get()
{
string ip = httpRequest.UserHostAddress;
}
}
I use Moq in the unit test:
Mock<HttpRequestBase> httpRequestMock = new Mock<HttpRequestBase>();
httpRequestMock.Setup(x => x.UserHostAddress).Returns("127.0.0.1");
// then pass httpRequestMock.Object to my controller ctor and good to go

Decouple your controller from the HTTP context. There might be some built-in functionality to do this with which I'm unfamiliar, but one approach would be to simply inject a mockable object. Consider something like this:
public interface IRequestInformation
{
string UserHostAddress { get; }
}
public class RequestInformation : IRequestInformation
{
public string UserHostAddress
{
get { return HttpContext.Current.Request.UserHostAddress; }
}
}
Now you've abstracted the dependency on HttpContext behind an interface. If you're using dependency injection, inject that interface into your controller. If you're not, you can fake it:
// in your controller...
private IRequestInformation _request;
public IRequestInformation RequestInfo
{
get
{
if (_request == null)
_request = new RequestInformation();
return _request;
}
set { _request = value; }
}
Then use that in your controller logic:
string ip = RequestInfo.UserHostAddress;
Now in your unit tests you can supply a mock/fake/etc. for the RequestInfo property. Either create one manually or use a mocking library. If you create one manually, that's simple enough:
public class RequestInformationFake : IRequestInformation
{
public string UserHostAddress
{
get { return "some known value"; }
}
}
Then just supply that to the controller when arranging the test:
var controller = new YourController();
controller.RequestInformation = new RequestInformationFake();
// run your test

Replace your references to HttpContext by references to HttpContextBase. When in your code, initialize the HttpContextBase with a HttpContextWrapper instance, which is a the default behavior implementation in a web stack.
However in your test inject a custom HttpContextBase implementation where you implement the methods and behaviors needed by your test only.
As precised in the link:
The HttpContextBase class is an abstract class that contains the same
members as the HttpContext class. The HttpContextBase class enables
you to create derived classes that are like the HttpContext class, but
that you can customize and that work outside the ASP.NET pipeline.
When you perform unit testing, you typically use a derived class to
implement members with customized behavior that fulfills the scenario
you are testing.

Add the following method to the controller, or inject the equivalent. It uses the magic string MS_HttpContext because that's what the AspNetWebStack implementation uses for exactly the same purpose.
HttpContextBase HttpContextBase => HttpContext.Current != null
? new HttpContextWrapper(HttpContext.Current)
: (HttpContextBase)Request.Properties["MS_HttpContext"]
Replace all other uses of HttpContext.Current in the controller with HttpContextBase.
When unit testing:
var context = new Mock<HttpContextBase>();
...
controller.Request = new HttpRequestMessage();
controller.Request.Properties["MS_HttpContext"] = context.Object;

unit testing dotnetopenauth ctp

I'm implementing an oauth provider using DotNetOpenAuth CTP library. So I have created an mvc3 application, which has an OAuth Controller with 3 methods in it with the purpose of authorizing third party applications. The controller has an IOAuthService which encapsulates all the logic that the library must do to complete certain tasks, however, the service methods return DotNetOpenOAuth objects that have their constructors protected.
I would like to test the behavior of the methods within my OAuthController, for this, I'm trying to mock my service methods but I havent't been able to do this. I have to tell moq library what type of object I'm expecting the service method to return, and since I cannot access constructors of these objects, I'm not able to perform a test over my controller method.
The controller:
public class OAuthController : Controller
{
private readonly IOAuthService _oAuthService;
public OAuthController(IOAuthService oAuthService)
{
_oAuthService = oAuthService;
}
[Authorize, AcceptVerbs(HttpVerbs.Get | HttpVerbs.Post)]
public ActionResult Authorize()
{
ClientApplication requestingClient;
var request = _oAuthService.ReadAuthorizationRequest();
if (request == null)
{
throw new HttpException((int)HttpStatusCode.BadRequest, "Missing authorization request.");
}
var response = _oAuthService.RequestClientAuthorization(GetIdentity().Name, out requestingClient, request);
if (response != null)
{
return response.AsActionResult();
}
var model = new AuthorizeClientApplicationViewModel
{
ClientApplication = requestingClient.Name,
Scope = request.Scope,
AuthorizationRequest = request,
};
return View(model);
}
public virtual IIdentity GetIdentity()
{
return User.Identity;
}
}
I want to test that whenever a third party app has no authorization, a view will pop up to the user asking for his permission to authorize the app. Fot this i need to mock:
_oAuthService.RequestClientAuthorization
The setup of my test method will then look like :
var oAuthService = new Mock<IOAuthService>();
oAuthService.Setup(a => a.RequestClientAuthorization(userName, out client, pendingRequest)).Returns(new OutgoingWebResponse()); // DotNetOpenAuth doesn't allow me to do the **new OutgoingWebResponse**
PD: For this question I only wrote one of the controller methods, but there are 3, and they have similar scenarios.

One possibility is to write a wrapper (the same way ASP.NET MVC abstracts all the HTTP Context specific stuff):
public abstract class OutgoingWebResponseWrapperBase
{
protected OutgoingWebResponseWrapperBase() { }
public abstract ActionResult AsActionResult();
}
and then have a naïve implementation:
public class OutgoingWebResponseWrapper: OutgoingWebResponseWrapperBase
{
private readonly OutgoingWebResponse _response;
public OutgoingWebResponseWrapper(OutgoingWebResponse response)
{
_response = response;
}
public override ActionResult AsActionResult()
{
return _response.AsActionResult();
}
}
Now modify the IOAuthService.RequestClientAuthorization method to return a OutgoingWebResponseWrapperBase instead of OutgoingWebResponse.
Just like that:
public interface IOAuthService
{
...
OutgoingWebResponseWrapperBase RequestClientAuthorization(...);
}
Obviously your controller code will stay absolutely the same. It's just that now you can mock the return type of the RequestClientAuthorization in your unit test because it is an abstract class. You can also mock the AsActionResult abstract method call to return some expected mocked instance and you will assert in your unit test that the controller action that you are testing returned this expected action result.

If the constructor is protected, then a derived type could access it. Can you simply use Moq to create a mock of OutgoingWebResponse (which internally will make Moq derive from it and call the protected constructor I think) and return that from your mock method implementation?
Something like this:
System.Net.HttpWebResponse mockResponse; // get this from somewhere
new Moq.Mock<DotNetOpenAuth.Messaging.OutgoingWebResponse>(mockResponse, 5);
This should let you mock up an OutgoingWebResponse. The next problem becomes, where do you get yoru HttpWebResponse instance, since that too has only a protected constructor. You could continue the chain and mock up that the same what as OutgoingWebResponse, and see how far you get.

Moq: unit testing a method relying on HttpContext

Consider a method in a .NET assembly:
public static string GetSecurityContextUserName()
{
//extract the username from request
string sUser = HttpContext.Current.User.Identity.Name;
//everything after the domain
sUser = sUser.Substring(sUser.IndexOf("\\") + 1).ToLower();
return sUser;
}
I'd like to call this method from a unit test using the Moq framework. This assembly is part of a webforms solution. The unit test looks like this, but I am missing the Moq code.
//arrange
string ADAccount = "BUGSBUNNY";
string fullADName = "LOONEYTUNES\BUGSBUNNY";
//act
//need to mock up the HttpContext here somehow -- using Moq.
string foundUserName = MyIdentityBL.GetSecurityContextUserName();
//assert
Assert.AreEqual(foundUserName, ADAccount, true, "Should have been the same User Identity.");
Question:
How can I use Moq to arrange a fake HttpContext object with some value like 'MyDomain\MyUser'?
How do I associate that fake with my call into my static method at MyIdentityBL.GetSecurityContextUserName()?
Do you have any suggestions on how to improve this code/architecture?

Webforms is notoriously untestable for this exact reason - a lot of code can rely on static classes in the asp.net pipeline.
In order to test this with Moq, you need to refactor your GetSecurityContextUserName() method to use dependency injection with an HttpContextBase object.
HttpContextWrapper resides in System.Web.Abstractions, which ships with .Net 3.5. It is a wrapper for the HttpContext class, and extends HttpContextBase, and you can construct an HttpContextWrapper just like this:
var wrapper = new HttpContextWrapper(HttpContext.Current);
Even better, you can mock an HttpContextBase and set up your expectations on it using Moq. Including the logged in user, etc.
var mockContext = new Mock<HttpContextBase>();
With this in place, you can call GetSecurityContextUserName(mockContext.Object), and your application is much less coupled to the static WebForms HttpContext. If you're going to be doing a lot of tests that rely on a mocked context, I highly suggest taking a look at Scott Hanselman's MvcMockHelpers class, which has a version for use with Moq. It conveniently handles a lot of the setup necessary. And despite the name, you don't need to be doing it with MVC - I use it successfully with webforms apps when I can refactor them to use HttpContextBase.

In general for ASP.NET unit testing, rather than accessing HttpContext.Current you should have a property of type HttpContextBase whose value is set by dependency injection (such as in the answer provided by Womp).
However, for testing security related functions I would recommend using Thread.CurrentThread.Principal (instead of HttpContext.Current.User). Using Thread.CurrentThread has the advantage of also being reusable outside a web context (and works the same in a web context because the ASP.NET framework always sets both values the same).
To then test Thread.CurrentThread.Principal I usually use a scope class that sets the Thread.CurrentThread to a test value and then resets on dispose:
using (new UserResetScope("LOONEYTUNES\BUGSBUNNY")) {
// Put test here -- CurrentThread.Principal is reset when PrincipalScope is disposed
}
This fits well with the standard .NET security component -- where a component has a known interface (IPrincipal) and location (Thread.CurrentThread.Principal) -- and will work with any code that correctly uses/checks against Thread.CurrentThread.Principal.
A base scope class would be something like the following (adjust as necessary for things like adding roles):
class UserResetScope : IDisposable {
private IPrincipal originalUser;
public UserResetScope(string newUserName) {
originalUser = Thread.CurrentPrincipal;
var newUser = new GenericPrincipal(new GenericIdentity(newUserName), new string[0]);
Thread.CurrentPrincipal = newUser;
}
public IPrincipal OriginalUser { get { return this.originalUser; } }
public void Dispose() {
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing) {
if (disposing) {
Thread.CurrentPrincipal = originalUser;
}
}
}
Another alternative is, instead of using the standard security component location, write your app to use injected security details, e.g. add an ISecurityContext property with a GetCurrentUser() method or similar, and then use that consistently throughout your application -- but if you are going to do this in the context of a web application then you might as well use the pre-built injected context, HttpContextBase.

[TestInitialize]
public void TestInit()
{
HttpContext.Current = new HttpContext(new HttpRequest(null, "http://tempuri.org", null), new HttpResponse(null));
}
Also you can moq like below
var controllerContext = new Mock<ControllerContext>();
controllerContext.SetupGet(p => p.HttpContext.Session["User"]).Returns(TestGetUser);
controllerContext.SetupGet(p => p.HttpContext.Request.Url).Returns(new Uri("http://web1.ml.loc"));

In ASP.NET MVC Core I use the following code to test controllers, which depend on HttpContext:
var controller = new HomeController();
controller.ControllerContext.HttpContext = new DefaultHttpContext();
This is a sample unit test:
[Test]
public void Test_HomeController_Index()
{
// Arrange
var controller = new HomeController();
controller.ControllerContext.HttpContext = new DefaultHttpContext();
// Act
var result = controller.Index();
// Assert
var viewResult = result as ViewResult;
Assert.IsNotNull(viewResult);
}

Have a look at this
http://haacked.com/archive/2007/06/19/unit-tests-web-code-without-a-web-server-using-httpsimulator.aspx
Using httpSimulator class,You will be able to do pass a HttpContext to handler
HttpSimulator sim = new HttpSimulator("/", #"C:\intepub\?")
.SimulateRequest(new Uri("http://localhost:54331/FileHandler.ashx?
ticket=" + myticket + "&fileName=" + path));
FileHandler fh = new FileHandler();
fh.ProcessRequest(HttpContext.Current);
HttpSimulator implement what we need to get a HttpContext instance. So you don't need to use Moq here.

If you're using the CLR security model (as we do) then you'll need to use some abstracted functions to get and set the current principal if you want to allow testing, and use these whenever getting or setting the principal. Doing this allows you to get/set the principal wherever is relevant (typically on HttpContext on the web, and on the current thread elsewhere like unit tests). This would look something like:
public static IPrincipal GetCurrentPrincipal()
{
return HttpContext.Current != null ?
HttpContext.Current.User :
Thread.CurrentThread.Principal;
}
public static void SetCurrentPrincipal(IPrincipal principal)
{
if (HttpContext.Current != null) HttpContext.Current.User = principal'
Thread.CurrentThread.Principal = principal;
}
If you use a custom principal then these can be fairly nicely integrated into its interface, for example below Current would call GetCurrentPrincipal and SetAsCurrent would call SetCurrentPrincipal.
public class MyCustomPrincipal : IPrincipal
{
public MyCustomPrincipal Current { get; }
public bool HasCurrent { get; }
public void SetAsCurrent();
}

This is not really related in using Moq for unit testing of what you need.
Generally we at work have a layered architecture, where the code on the presentation layer is really just for arranging things for being displayed on the UI. This kind of code is not covered with unit tests. All the rest of the logic resides on the business layer, which doesn't have to have any dependency on the presentation layer (i.e. UI specific references such as the HttpContext) since the UI may also be a WinForms application and not necessarily a web application.
In this way you can avoid to mess around with Mock frameworks, trying to simulate HttpRequests etc...although often it may still be necessary.