Multiple endpoints

Multiple endpoints

What: faking multiple request endpoints

Why: unit testing a service that makes requests to multiple endpoints during one execution/run. For example, return the Order information and then the User Information (from two separate API endpoints) and return those two results into a single projection/instance.

How: Create a fake response for each endpoint the method calls.

Ok - so here's the main UNIT TEST class. For the full test code, please reference the tests here.

[Fact]
public async Task GivenSomeValidHttpRequests_GetSomeDataAsync_ReturnsAFoo()
{
    // Arrange.

    // 1. First fake response.
    const string responseData1 = "{ \"Id\":69, \"Name\":\"Jane\" }";
    var messageResponse1 = FakeHttpMessageHandler.GetStringHttpResponseMessage(responseData1);

    // 2. Second fake response.
    const string responseData2 = "{ \"FavGame\":\"Star Wars\", \"FavMovie\":\"Star Wars - all of em\" }";
    var messageResponse2 = FakeHttpMessageHandler.GetStringHttpResponseMessage(responseData2);

    // Prepare our 'options' with all of the above fake stuff.
    var options = new[]
    {
        new HttpMessageOptions
        {
            RequestUri = new Uri("https://api.YouWebsite.com/something/here-1"), // Endpoint #1.
            HttpResponseMessage = messageResponse1 // Fake response for this endpoint #1.
        },
        new HttpMessageOptions
        {
            RequestUri = new Uri("https://api.YouWebsite.com/something/here-2"), // Endpoint #2.
            HttpResponseMessage = messageResponse2 // Fake response for this endpoint #2.
        }
    };

    // 3. Use the fake responses if those urls are attempted.
    var messageHandler = new FakeHttpMessageHandler(options);

    var myService = new MyService(messageHandler);

    // Act.
    // NOTE: network traffic will not leave your computer because you've faked the response, above.
    var result = await myService.GetAllDataAsync();

    // Assert.
    result.Id.ShouldBe(69); // Returned from GetSomeFooDataAsync.
    result.Baa.FavMovie.ShouldBe("Star Wars - all of em"); // Returned from GetSomeBaaDataAsync.
    options[0].NumberOfTimesCalled.ShouldBe(1);
    options[1].NumberOfTimesCalled.ShouldBe(1);
}