Unit Testing of Remote API calls, How it works with JSON Objects - json

Question

In my web api, I have a method that call a service that return a deserialized JSON object. I can't find a way for unit testing that is working for me.
the following is the code from the controller:
[RequireHttps]
[Route("api/GetItem/{id}")]
public class GetItemController : ControllerBase
{
private static HttpClient client = new HttpClient();
private Item item = new Item();
[RequireHttps]
[Route("api/GetItem/{id}")]
public Item GetItem(string name, string password)
{
string url = "https://localhost:5001/";
string uri = url + "api/item/" + name+ "/" + password "/" ;
client.DefaultRequestHeaders.Accept.Add(new
MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage Res = client.GetAsync(uri).Result;
if (Res.IsSuccessStatusCode)
{
var MemResponse = Res.Content.ReadAsStringAsync().Result;
member = JsonConvert.DeserializeObject<Item>
(MemResponse);
}
return Ok(item);
}
}
The unit test I wrote suppose to check the wrong user name and password, but when running the test it just gray out and never runs
[TestMethod]
public void GetItemWithWrongPassword()
{
var username = "Hellow";
var pass = "There";
var controller = new GetItemController();
var response = controller.GetItem(username, pass);
var s = response.ToString();
Assert.AreEqual(s, "System.Web.Http.Results.NotFoundResult");
}
what I'm doing wrong?
Later on I want to test if the connection to the remote API.

Answer 1

Creating an instance of GetItemController and calling its methods is not a good idea, because the whole message pipeline is skipped in the process.
I see two options here:
Put the code (including the HttpClient) that is contained in GetItem into another class and call the method on an instance of that class, e.g.:
public class ItemClient
{
private static HttpClient client = new HttpClient();
public Item GetItem(string name, string password)
{
Item item = null;
string url = "https://localhost:5001/";
string uri = url + "api/item/" + name + "/" + password;
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage Res = client.GetAsync(uri).Result;
if (Res.IsSuccessStatusCode)
{
var MemResponse = Res.Content.ReadAsStringAsync().Result;
item = JsonConvert.DeserializeObject<Item>(MemResponse);
}
return item;
}
}
Controller method:
[RequireHttps]
[Route("api/GetItem/{name}/{password}")]
public Item GetItem(string name, string password)
{
ItemClient client = new ItemClient();
var item = client.GetItem(name, password);
return Ok(item);
}
Test method:
[TestMethod]
public void GetItemWithWrongPassword()
{
var username = "Hellow";
var password = "There";
ItemClient client = new ItemClient();
var item = client.GetItem(username, password);
Assert.IsNull(item);
}
Call the controller method using a HttpClient in the test method:
[TestMethod]
public void GetItemWithWrongPassword()
{
var username = "Hellow";
var password = "There";
string url = "https://localhost/"; // Host of your Web API
string uri = url + "api/GetItemController/GetItem/" + username + "/" + password;
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage Res = client.GetAsync(uri).Result;
var s = Res.ToString();
Assert.AreEqual(s, "System.Web.Http.Results.NotFoundResult");
}
I personally prefer option 1 due to two benefits:
Debugging the test is easier. Debugging a call by HttpClient (option 2)
usually means that you have to start a second instance of Visual
Studio and set a breakpoint there.
The code can be used in other projects that are not Web API services. The endpoints become simple wrappers around the actual business logic.