Mocking Asp.net-mvc Controller Context

Question

So the controller context depends on some asp.net internals. What are some ways to cleanly mock these up for unit tests? Seems like its very easy to clog up tests with tons of setup when I only need, for example, Request.HttpMethod to return "GET".

I've seen some examples/helpers out on the nets, but some are dated. Figured this would be a good place to keep the latest and greatest.

I'm using latest version of rhino mocks

Answer 1

Using MoQ it looks something like this:

var request = new Mock<HttpRequestBase>();
request.Expect(r => r.HttpMethod).Returns("GET");
var mockHttpContext = new Mock<HttpContextBase>();
mockHttpContext.Expect(c => c.Request).Returns(request.Object);
var controllerContext = new ControllerContext(mockHttpContext.Object
, new RouteData(), new Mock<ControllerBase>().Object);

I think the Rhino Mocks syntax is similar.

Answer 2

Here is a sample unit test class using MsTest and Moq which mocks HttpRequest and HttpResponse objects. (.NET 4.0, ASP.NET MVC 3.0 )

Controller action get value from request and sets http header in response objects. Other http context objects could be mocked up in similar way

[TestClass]
public class MyControllerTest
{
    protected Mock<HttpContextBase> HttpContextBaseMock;
    protected Mock<HttpRequestBase> HttpRequestMock;
    protected Mock<HttpResponseBase> HttpResponseMock;

    [TestInitialize]
    public void TestInitialize()
    {
        HttpContextBaseMock = new Mock<HttpContextBase>();
        HttpRequestMock = new Mock<HttpRequestBase>();
        HttpResponseMock = new Mock<HttpResponseBase>();
        HttpContextBaseMock.SetupGet(x => x.Request).Returns(HttpRequestMock.Object);
        HttpContextBaseMock.SetupGet(x => x.Response).Returns(HttpResponseMock.Object);
    }

    protected MyController SetupController()
    {
        var routes = new RouteCollection();
        var controller = new MyController();
        controller.ControllerContext = new ControllerContext(HttpContextBaseMock.Object, new RouteData(), controller);
        controller.Url = new UrlHelper(new RequestContext(HttpContextBaseMock.Object, new RouteData()), routes);
        return controller;
    }

    [TestMethod]
    public void IndexTest()
    {
        HttpRequestMock.Setup(x => x["x"]).Returns("1");
        HttpResponseMock.Setup(x => x.AddHeader("name", "value"));

        var controller = SetupController();
        var result = controller.Index();
        Assert.AreEqual("1", result.Content);

        HttpRequestMock.VerifyAll();
        HttpResponseMock.VerifyAll();
    }
}

public class MyController : Controller
{
    public ContentResult Index()
    {
        var x = Request["x"];
        Response.AddHeader("name", "value");
        return Content(x);
    }
}

Answer 3

Here's a snippet from Jason's link. Its the same as Phil's method but uses rhino.

Note: mockHttpContext.Request is stubbed to return mockRequest before mockRequest's internals are stubbed out. I believe this order is required.

// create a fake web context
var mockHttpContext = MockRepository.GenerateMock<HttpContextBase>();
var mockRequest = MockRepository.GenerateMock<HttpRequestBase>();
mockHttpContext.Stub(x => x.Request).Return(mockRequest);

// tell the mock to return "GET" when HttpMethod is called
mockRequest.Stub(x => x.HttpMethod).Return("GET");            

var controller = new AccountController();

// assign the fake context
var context = new ControllerContext(mockHttpContext, 
                  new RouteData(), 
                  controller);
controller.ControllerContext = context;

// act
...