FluentHttpClientMock

A fluent builder interface to create mock HttpClients in C#

A System.Net.HttpClient class cannot be mocked in unit tests as it does not implement an interface that exposes its HTTP operations.

FluentHttpClientMock creates an HttpClient instance with set conditions and expectations. If at least once condition is not met, the expectation will not be set. This is in alignment with well-known mocking frameworks such as Rhino Mocks, Moq and NSubstitute.

Syntax

Instantiate a mocker

var mocker = HttpClientMocker.Create();

Set HTTP response body based on calling URL

mocker.When.AbsoluteUrlIs("https://path.to.url/")
.Then.ResponseShouldBe("Response content");

Set HTTP response body based on request body

mocker.When.RequestMessageStringIs("Request content")
.Then.ResponseShouldBe("Response content");

Chain both conditions

mocker.When.RequestMessageStringIs("Request content")
.And.AbsoluteUrlIs("https://path.to.url/")
.Then.ResponseShouldBe("Response content");

Asserting HTTP requests

The HttpClientMocker class exposes members that return certain data that was sent through the mocked HTTP client.

AbsoluteRequestUri returns the absolute URI that the HTTP client used to make its last HTTP call RequestContent returns the content body that the HTTP client sent last

Building the project

The project uses Cake for its build process. Running build.ps1 (Remote Signed script) will version and compile the project, run the unit tests and create a NuGet package. If you don't want to package the project at this moment, you can change the final build task on the last line (RunTarget("Package");) to "RunTarget("Package");".

The mocker is written in .NET Standard 2.0