Unit testing with xUnit in .NET Core

This post is about Unit testing with xUnit in .NET Core. The last few weeks I was working on a new  project in .NET Core. What I didn’t expected was that so many features weren’t documented or very bad documented. Many articles of Microsoft explained a different solution for the same result. I understand the framework is changing but the documentation should be changing as well then.

So I started unit testing with xUnit. I like the framework a lot so I hoped everything was working in the latest version of .NET Core. What I wanted to achieve was to create of course unit tests but also good integration in Visual Studio and TFS. That was not so easy as I hoped for. It took me a lot of searching and combining of solution to get everything working. Just because of the poor documentation. If you see the result to get this to work then it looks to easy.

First, which version of all the tools and Frameworks did I use:

  • Visual Studio 2017 Enterprise 15.2 (26430.12)
  • ReSharper 2017.1.2
  • dotnet version 1.0.4 (dotnet –version in command prompt)
  • Team Foundation Server 2017 Update 1

When I used the xUnit Nuget package I got with little effort the tests working in Visual Studio. But I wanted more. Because I’m CI/CD engineer, I wanted some automated builds in Team Foundation Server. So I created a new CI build for my project. I couldn’t get everything to work with the tasks that where in TFS so I used the command prompt task. I found this post from xUnit for testing in .NET Core that got me pointing in the right direction.

I installed the following Nuget packages in my project:

This gave me access to the new xunit CLI. I also installed the VS runner package so you could also run the unittests with the “Test Explorer” window in Visual Studio.

Now I could finish my CI Build definition. I removed all the tasks because in every combination that I tried I couldn’t get a part to work. I still wanted, to build the project, run the test, see the results back in Visual Studio and in TFS. As a bonus I wanted to see the Code Coverage of the tests in TFS as well.

First restore all external dependencies:

Then build the project:

Run the tests:


The trick is to use the right configuration and to export the result to an xml file. Place that file in the “$(Build.ArtifactStagingDirectory)” so we can use it in the next step. We already build the solution so add the “-nobuild” option.

Upload the test results:

The Code Coverage was not possible because that is still under development by Microsoft for the .NET Core framework. In the next version of Visual Studio will this be possible. You can already test it in the Visual Studio 2017 15.3 preview version. See this thread on Github for more information.

The result is:

Web API load testing with Visual Studio webtest

This is the first post about load testing with Visual Studio webtest. This series of posts is describing load testing on a Visual Studio Web API.

This first post is about setting up the Visual Studio webtest for the demo Web API project with Visual Studio 2015. We’re using the latest version of the .NET Framework so we can use all the latest cool stuff in our code.

Setup the project

  1. Create a new WebApi project and don’t forget to set the .NET Framework version to 4.6. Remember, I use the new Visual Studio 2015 RTM version.
  2. Create a new class library and call it “Extensions”.
  3. In the Extensions project, add a reference to “Microsoft.VisualStudio.QualityTools.WebTestFramework”. This project is for creating custom extension for Visual Studio webtests.
  4. Add again a new project. Choose a “Web Performance and Load test Project” project. I called mine “WebApiTest”.
  5. Add a reference from the test project to the Extensions project so we can use the extensions in the webtests.

So, the first thing is done. Setting up the project is the easy part. Now comes the testing part.

When you created the test project, a new empty webtest is created. We are now going to change the request so we can test it.

  1. Rename the webtest to ValuesTest because we are going to test the ValuesController of the Web Api project.
  2. Right click your ValuesTest and add a “Web Service Request”. Change the url to “http://localhost:26159/api/values” (your portnumber can be different).
  3. Change the method from POST to GET.
  4. Run your test and you will get a 401 unauthorized request back.
  5. Remove the Authorize attribute on the ValuesController
  6. Run the webtest again and now you will get a status 200 with as response “Binary Data”. This is off course your JSON response message.

Now we have to validate your response message because we don’t know if your test is sending the correct message.

  1. Right click your web request and select “Add Validation Rule”.
  2. A window appears. Select the “Find text” validation rule.
    Webstest add validation rule
  3. Enter in the “Find text” property the value “value3”.
  4. Run your test and your test will fail on the validation rule.
    Find text validation rule value3 failed
  5. Change the “Find text” property to “value2”.
  6. Run the test again and now your test will be valid.
    Find text validation rule value2 passed

Ok. The foundation is done for the testing part. We have a test project and a source project that must be validated. The extensions part isn’t used yet. This will be done in the next part. In that part we are going to create a more detailed ValidationRule that really understand JSON reponses. Then we don’t have to “find text” in the reponse but we can search for a property that we want to validate.