Testing .Net C# WebAPI methods with NUnit and HttpResponseMessage

I recently wrote my first NUnit test for a .Net WebAPI controller. I learned two interesting things. (The code has been simplified to be more explicit).

1. When you create your controller, set a value for it's "Request" object.

//helper function to create testable "projects" controller
private ProjectsController GetTestProjectsController()
{
    ProjectsController controller = 
         new ProjectsController(logger, new ProjectRepository())
    {
        Request = new HttpRequestMessage()
        {
            Properties = { { HttpPropertyKeys.HttpConfigurationKey, 
                 new HttpConfiguration() } }
        }
    };
    return controller;
}

2. When retrieving an object use the TryGetContentValue() method to extract the returned value as a C# object. Notice on line 18 we free the C# object from the clutches of the evil HttpResponseMessage object.

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[Test] public void GetTestWithExistingProjectName() { string projectName = "GetTestWithProjectName"; var projectRepository = new ProjectRepository(); // Arrange DeleteProjectIfItExists(projectRepository, projectName); var newTestProject = CreateNewTestProjectAndWriteToRepository(projectName,projectRepository); var controller = GetTestProjectsController(); // Act HttpResponseMessage httpResponseMessage = controller.Get(projectName); // Assert Assert.IsTrue(httpResponseMessage.IsSuccessStatusCode); Project project = null; httpResponseMessage.TryGetContentValue(out project); Assert.AreEqual(projectName, project.Name); //cleanup DeleteProjectIfItExists(projectRepository, projectName); }

This is the code for the api GET.

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public HttpResponseMessage Get(string name) { var project = _projectRepository.GetProjectByName(name); if (project != null) { return Request.CreateResponse(HttpStatusCode.OK, project); } return Request.CreateErrorResponse(HttpStatusCode.NotFound, "Sorry, the project '" + name + "' could not be found."); }

Special thanks to the folks at hilite.me for their awesome code highlighter site.