I'm having difficulty testing controllers. Original my controller for testing looked something like this:
SomethingController CreateSomethingController()
{
var somethingData = FakeSomethingData.CreateFakeData();
var fakeRepository = FakeRepository.Create();
var controller = new SomethingController(fakeRepository);
return controller;
}
This works fine for the majority of testing until I got the Request.IsAjaxRequest() part of code. So then I had to mock up the HttpContext and HttpRequestBase. So my code then changed to look like:
public class FakeHttpContext : HttpContextBase
{
bool _isAjaxRequest;
public FakeHttpContext( bool isAjaxRequest = false )
{
_isAjaxRequest = isAjaxRequest;
}
public override HttpRequestBase Request
{
get
{
string ajaxRequestHeader = "";
if ( _isAjaxRequest )
ajaxRequestHeader = "XMLHttpRequest";
var request = new Mock<HttpRequestBase>();
request.SetupGet( x => x.Headers ).Returns( new WebHeaderCollection
{
{"X-Requested-With", ajaxRequestHeader}
} );
request.SetupGet( x => x["X-Requested-With"] ).Returns( ajaxRequestHeader );
return request.Object;
}
}
private IPrincipal _user;
public override IPrincipal User
{
get
{
if ( _user == null )
{
_user = new FakePrincipal();
}
return _user;
}
set
{
_user = value;
}
}
}
SomethingController CreateSomethingController()
{
var somethingData = FakeSomethingData.CreateFakeData();
var fakeRepository = FakeRepository.Create();
var controller = new SomethingController(fakeRepository);
ControllerContext controllerContext = new ControllerContext( new FakeHttpContext( isAjaxRequest ), new RouteData(), controller );
controller.ControllerContext = controllerContext;
return controller;
}
Now its got to that stage in my controller where I call Url.Route and Url is null. So it looks like I need to start mocking up routes for my controller.
I seem to be spending more time googling on how to fake/mock objects and then debugging to make sure my fakes are correct than actual writing the test code. Is there an easier way in to test a controller? I've looked at the TestControllerBuilder from MvcContrib which helps with some of the issues but doesn't seem to do everything. Is there anything else available that will do the job and will let me concentrate on writing the tests rather than writing mocks?
Thanks
You can use some of the libraries that give you out of the box some of these objects. For example RhinoMock, NMock ... etc. I personally use Moq - it's good enough and free. What i like most in Moq is the linq expressions.
Most mocking engine will do all this for you. I use RhinoMocks but there are a lot more available. Also Moles is very new and interesting mocking engine (this generally comes with Pex which is yet more ammo in your unit testing arsenal)
MvcContrib + RhinoMocks. Check out the TestControllerBuilder in the MvcContrib.TestHelper library. Here's the official write-up: http://mvccontrib.codeplex.com/wikipage?title=TestHelper#Examples.
Here's an example of mocking a controller out for testing a UrlHelper: ASP.NET MVC: Mock controller.Url.Action
Here's a short explanation of how to use the TestControllerBuilder: http://codebetter.com/blogs/kyle.baley/archive/2008/03/19/testcontrollerbuilder-in-mvccontrib.aspx
Instead of mocking stuff, you can pass IAjaxRequest to constructor. Or make it base constructor class property (and use property injection). Or you can make your constructor implement IAjaxRequest and then apply global action filter on base constructor class that will setup IAjaxRequest.
This will help to abstract many things, including HttpContext stuff. Just don't abstract IHttpContext, abstract IUserContext, ISessionStorage, IAuthentication, IRequestDetails...
Another way is to use model binder directly on methods where you need specific information. See this post for example. You can make binder that will give you IsAjaxRequest, then you just make action to accept this parameter. Works very well because information is provided exactly to the method that needs it, not to the whole controller.
Related
I know the difference between HttpContext and HttpContextWrapper is below...
HttpContext
This is the vintage asp.net context. The problem with this is that it has no base class and isn't virtual, and hence is unusable for testing (cannot mock it). It's recommended to not pass it around as function arguments, instead pass around variables of type HttpContextBase.
HttpContextBase
This is the (new to c# 3.5) replacement to HttpContext. Since it is abstract, it is now mockable. The idea is that your functions that expect to be passed a context should expect to receive one of these. It is concretely implemented by HttpContextWrapper
HttpContextWrapper
Also new in C# 3.5 - this is the concrete implementation of HttpContextBase. To create one of these in a normal webpage, use new HttpContextWrapper(HttpContext.Current).
The idea is that to make your code unit-testable, you declare all your variables and function parameters to be of type HttpContextBase, and use an IOC framework eg Castle Windsor to get it injected. In normal code, castle is to inject the equivalent of 'new HttpContextWrapper
(HttpContext.Current)', whereas in test code you're to be given a mock of HttpContextBase.
But I am not aware about its real use. I heard that it's useful in Unit Testing in comparing with Web Forms. but how it's useful ?
I also know that we can use it to execute the controller and Action as mentioned here
I heard that it's useful in Unit Testing in comparing with Web Forms. but how it's useful ?
Let's take an example of an ASP.NET MVC controller action which is adding a cookie to the response:
public class HomeController : Controller
{
public ActionResult Index()
{
var cookie = new HttpCookie("foo", "bar");
this.Response.Cookies.Add(cookie);
return View();
}
}
Notice the Response property over there. It's an HttpResponseBase. So we can mock it in a unit test:
public class HttpResponseMock: HttpResponseBase
{
private HttpCookieCollection cookies;
public override HttpCookieCollection Cookies
{
get
{
if (this.cookies == null)
{
this.cookies = new HttpCookieCollection();
}
return this.cookies;
}
}
}
public class HttpContextMock: HttpContextBase
{
private HttpResponseBase response;
public override HttpResponseBase Response
{
get
{
if (this.response == null)
{
this.response = new HttpResponseMock();
}
return this.response;
}
}
}
and now we could write a unit test:
// arrange
var sut = new HomeController();
var httpContext = new HttpContextMock();
sut.ControllerContext = new ControllerContext(httpContext, new RouteData(), sut);
// act
var actual = sut.Index();
// assert
Assert.AreEqual("bar", sut.Response.Cookies["foo"].Value);
And since all members are virtual we could use a mocking framework which would avoid us the need to write those mock classes for the unit test. For example with NSubstitute here's how the test might look:
// arrange
var sut = new HomeController();
var context = Substitute.For<HttpContextBase>();
var response = Substitute.For<HttpResponseBase>();
var cookies = new HttpCookieCollection();
context.Response.Returns(response);
context.Response.Cookies.Returns(cookies);
sut.ControllerContext = new ControllerContext(context, new RouteData(), sut);
// act
var actual = sut.Index();
// assert
Assert.AreEqual("bar", sut.Response.Cookies["foo"].Value);
Now let's take a WebForm:
protected void Page_Load(object sender, EventArgs)
{
var cookie = new HttpCookie("foo", "bar");
this.Response.Cookies.Add(cookie);
}
In this case the Response property is the concrete HttpResponse. So you are busted. Impossible to unit test in isolation.
[HttpPost]
public ActionResult Create(Car car)
{
_repository.CreateCar(car);
_repository.UpdateRegistrationDetails(car);
}
What I'm wanting to do is write unit test to ensure that Create calls CreateCar and UpdateRegistrationDetails. It doesn't matter about what happens in these methods but just that they get called. Could someone please tell me how to do this? Do I need to use a mocking framework for this? I have RhinoMocks installed to use. Do you use the Expect in RhinoMocks?
Again using Moq I think you need to mock the Repository instead (assuming names here of course)
var mock = new Mock<IRepository>();
var controller = new Controller(mock.Object); //assuming this is how you create it
var car = new Car();
controller.Create(car);
mock.Verify(x => x.CreateCar(car));
mock.Verify(x => x.UpdateRegistrationDetails(car));
No need for Setup or Expect as the mocked methods do not return anything
[EDIT]
Here is a Rhino.Mocks example
var mock = MockRepository.GenerateStub<IRepository>();
var controller = new Controller(mock); //assuming this is how you create it
var car = new Car();
controller.Create(car);
mock.AssertWasCalled(x => x.CreateCar(car));
mock.AssertWasCalled(x => x.UpdateRegistrationDetails(car));
The best answer is to use a mocking framework as others here have mentioned. The dirty way, but sometimes faster if you don't want to learn mocking frameworks (which you really should) is to create a test class and override virtual methods. In your case something like
public class RepoUnderTest : Repo
{
public bool UpdateRegistrationDetailsCalled = false;
public override void UpdateRegistrationDetails(Car car)
{
base.UpdateRegistrationDetails(car);
UpdateRegistrationDetailsCalled = true;
}
}
then you can test something similar to
[HttpPost]
public ActionResult Create(Car car)
{
// Arrange
var _repository = new RepoUnderTest();
// Act
_repository.CreateCar(car);
// Assert
Assert.IsTrue(_repository.UpdateRegistrationDetailsCalled);
}
Again a mocking framework is best. And I'd vote for those, but sometimes this is an easy introduction to testing for these things before you get heavier into mocking.
Regarding using of Expect() in RhinoMocks. I preffer to use stubs and 'Stub()' or AssertWasCalled() methods as much as possible. Expect() is used in cases when nothing else works.
I'm developing a webapp using ASP.NET MVC and C#. And I'm creating a unit test for this webapp using NUnit and Rhino Mock. My problem is that I have a Response object in my controller's action method and when I execute my unit test my test is failing because the Response object is a null reference.
Do I need to separate this Response object call in my actions or there is a better way to resolve this?
public ActionResult Login( string user, string password )
{
Response.Cookies[ "cookie" ].Value = "ck";
...
return View();
}
Please advise.
Many thanks.
What the controller really lacks is its HttpContext. In a test method it should be added explicitly if needed:
[Test]
public void TestMethod()
{
// Assume the controller is created once for all tests in a setup method
_controller.ControllerContext.HttpContext = new DefaultHttpContext();
var result = _controller.Login("username", "verySaf3Passw0rd");
// Asserts here
}
This is one of the annoying points where ASP.NET MVC is not as testable and loosely coupled as it could be. See this question for some suggestions how to mock the HTTP context objects.
I ended up creating a real response that my mock context returns like this...
Mock<HttpSessionStateBase> mockSession;
Mock<ControllerContext> mockContext;
Mock<ISessionProvider> mockSessionProvider;
HttpResponse testResponse;
MyController controller;
[TestInitialize]
public void Initialize()
{
testResponse = new HttpResponse(TextWriter.Null);
mockContext = new Mock<ControllerContext>();
mockSession = new Mock<HttpSessionStateBase>();
mockContext.Setup(x => x.HttpContext.Session).Returns(mockSession.Object);
mockContext.Setup(x => x.HttpContext.Response).Returns(new HttpResponseWrapper(testResponse));
controller = new MyController();
controller.ControllerContext = mockContext.Object;
}
I am new in unit test and MVC development.
I have a question for using moq for unit testing in asp.net mvc. I have a controller which accepts an ajax action:
[HttpPost,Authorize]
public ActionResult GrabLink()
{
string username = HttpContext.User.Identity.Name;
string rssUrl = Request.Params["Grablink"].ToString();
...}
This action deals with the http request which I generate from the view:
var mockRequest = new Moq.Mock<HttpRequestBase>();
but I can not find a way to define the parameters I used in the class. Also, is there any way to use the value binding provider directly to pass the value to the controller if I would like to do an ajax post?
I am a newbie in handling web request. If you have some good tutorial for better understanding the Http request (as well as the Httpcontext and related classes in asp.net) please post here. Thank you very much!
This works very well for me:
var controller = new HomeController();
var context = new Mock<HttpContextBase>(MockBehavior.Strict);
var controllerContext = new Mock<ControllerContext>();
controllerContext.SetupGet(x => x.HttpContext.User.Identity.Name)
.Returns("TestUser");
controllerContext.SetupGet(x => x.HttpContext.User.Identity.IsAuthenticated)
.Returns(true);
controllerContext.SetupGet(x => x.HttpContext.Request.IsAuthenticated)
.Returns(true);
controller.ControllerContext = controllerContext.Object;
// As a bonus, instantiate the Url helper to allow creating links
controller.Url = new UrlHelper(
new RequestContext(context.Object, new RouteData()), new RouteCollection());
This will allow you to initialize any user you want as an authenticated user, and the last line will allow you to user the Url helper within the controller even though you're calling it from a unit test.
As Scott said HttpContext makes Controllers hard to test. Anyway he's got a pretty solution at here.
BTW why didn't you make rssUrl a parameter if it is assigning by POST or GET?
e.g.
//POST: /GrabLink?rssUrl=bla bla...
[HttpPost,Authorize]
public ActionResult GrabLink(IPrincipal user, string rssUrl) {
string userName = user.Name;
}
Ok, #cem covered your second question very well.
For your first, nerddinner, and If I'm not mistaken, when you create a new Internet Application with Unit test, in Visual Studio, have the following mock classes for HttpContext. Its at the bottom of this file.
You could use these (or create a new Internet App +Tests with VS) and copy all the fake classes for your tests. (I wrote a Moq example below)
It looks like this:
public class MockHttpContext : HttpContextBase {
private IPrincipal _user;
public override IPrincipal User {
get {
if (_user == null) {
_user = new MockPrincipal();
}
return _user;
}
set {
_user = value;
}
}
public override HttpResponseBase Response
{
get
{
return new MockHttpResponse();
}
}
}
public class MockHttpResponse : HttpResponseBase {
public override HttpCookieCollection Cookies
{
get
{
return new HttpCookieCollection();
}
}
}
Not tested, but to Use mock it would look like this:
var fakeReqBase = new Mock<HttpRequestBase>();
fakeReqBase.Setup(f => f.User).Returns(new GenericIdentity("FakeUser"));
//generic identity implements IIdentity
fakeUserRepo.Object;//this returns fake object of type HttpRequestBase
Checkout the Moq Quickstart. Its quite easy to get used to, and the fluent interface really helps.
I am trying to test the User.IsInRole("Administrator") in my application, and actually trying to assign the User Role to ("Administrator") so that my test will pass. I am using Scott Hanselman's MvcMockHelpers to do this, and at the moment I have the following test.
[Test]
public void Create_CanInsertNewArticleView_IsNotNull()
{
// Arrange
var controller = new ArticleController();
MockRepository mockRepo = new MockRepository();
var fakeContext = MvcMockHelpers.FakeHttpContext(mockRepo, "~/Article/Create");
fakeContext.User.IsInRole("Administrator");
// Act
Article fakeArticle = FakeObjects.ReturnFakeArticle();
var result = controller.Create(fakeArticle) as ViewResult;
// Assert
Assert.IsNotNull(result);
}
However the actual controller's User is null at the moment.
Can anyone help me out and tell me what the correct test should be, to User.IsInRole("Administrator")
Thanks for your help and time
Johann
See this related answer for details.
Here's the code snippet from the other answer converted to Rhino Mocks:
var user = new GenericPrincipal(new GenericIdentity(string.Empty), null);
var httpCtx = MockRepository.GenerateStub<HttpContextBase>();
httpCtx.User = user;
var controllerCtx = new ControllerContext();
controllerCtx.HttpContext = httpCtx;
sut.ControllerContext = controllerCtx;
You'll have to mock an IPrincipal for your user object, set it up so that .IsInRole("Administrator") returns true, and then set your fakeContext up to return that IPrincipal for the.User property. It would be something like this:
EDIT: It turns out the OP is using Rhino Mocks, and the code I provided was for Moq. Here's an attempt att writing Rhino code, although I have never actually used Rhino myself. The original Moq code can be found below.
In Rhino Mocks, you'll want to add another helper method, or change the current one, so you have the following:
public static HttpContextBase FakeHttpContext(this MockRepository mocks, string url, IPrincipal user)
{
// Do the same setup as Scott does...
// ...and add this:
SetupResult.For(context.User).Return(user);
mocks.Replay(context);
return context,
}
Then you declare and set up your IPrincipal mock object like this before the call to FakeHttpContext, and send the mock object in as the third parameter.
In Moq:
fakeContext = MvcMockHelpers.FakeHttpContext("~/Article/Create");
fakeUser = new Mock<IPrincipal>();
fakeUser.Expect(usr => usr.IsInRole(It.IsAny<String>())).Returns(true);
fakeContext.Expect(context => context.User).Returns(fakeUser.Object);
(Disclaimer: It was a while since I wrote a unit test, and this code has not been tested even for compilation errors. Hence, there might be some wrinkles that need to be ironed out before you can use this code, but you get the general idea...)