How to mock the new HttpClientFactory in .NET Core 2.1 using Moq

Question

.NET Core 2.1 comes with this new factory called HttpClientFactory, but I can\'t figure out how to mock it to unit test some methods that include REST service c

Answer 1

In addition to the previous post that describes how to setup a stub, you can just use Moq to setup the DelegatingHandler:

var clientHandlerMock = new Mock();
clientHandlerMock.Protected()
    .Setup>("SendAsync", ItExpr.IsAny(), ItExpr.IsAny())
    .ReturnsAsync(new HttpResponseMessage(HttpStatusCode.OK))
    .Verifiable();
clientHandlerMock.As().Setup(s => s.Dispose());

var httpClient = new HttpClient(clientHandlerMock.Object);

var clientFactoryMock = new Mock(MockBehavior.Strict);
clientFactoryMock.Setup(cf => cf.CreateClient()).Returns(httpClient).Verifiable();

clientFactoryMock.Verify(cf => cf.CreateClient());
clientHandlerMock.Protected().Verify("SendAsync", Times.Exactly(1), ItExpr.IsAny(), ItExpr.IsAny());