Utilizing Web API on client side

Question

I have created a simple web api controller in mvc4 containing 4 methods (one for each CRUD operation). I'm able to use fiddler to test that the methods in my controller work.

I'm now trying to make a unit test to prove that these work. I've managed to serialize my client side object into json format, but now how do I use this string of json to actually invoke my methods?

If it helps, I am using Json.NET to serialize my client object - although I don't think this extention actually handles the delivery and retreival of it to the server.

Answer 1

Your unit tests should be written against the controller - so you don't need to make an actual HTTP request to unit test your Web API code, you just call the methods.

From a design perspective, if you want a restful Web API, the client should be able to send a standard HTTP message without having to serialize the request.

Answer 2

This is the kind of approach I have used to post an object to a restful Web API:

HttpResponseMessage response;
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("http://url_to_service");
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

var responseTask = client.PostAsJsonAsync("api/resource/somethingelse", someObjectToPost).Result;
responseTask.Wait();
response = responseTask.Result;

if (response.IsSuccessStatusCode)
{
    var contentTask = response.Content.ReadAsAsync<SomeResponseType>();
    contentTask.Wait();
    SomeResponseType responseContent = contentTask.Result;
}
else
{
    //Handle error.
}

In this case, someObjectToPost is your client-side object, though you can leave it to Web API to serialize it for you. In the above example I am assuming the reponse is of fictional type SomeResponseType - you can also use ReadAsStringAsync if the response is expected to be plain text.

Answer 3

The code presented here by nick_w is correct. You need to use HttpClient object. And as Steve Fenton mentioned, to create unit test you don't want to do it - rather test directly against controller. But for the functional test you can do it. I've done same thing. I've created helper class so I need only to call one of Http helper methods, depending if it is GET or POST, etc. that I do. This helper uses generic types so it operates with any types that being passed.