Facilitation.md

Test your Architecture with ArchUnit

Learning Goals

• Understand the advantages of using a library like ArchUnit
• Clarify how we can use it on a daily basis

Connect - Architecture?

In group, discuss:

• What are your current architecture rules inside your team
• How you ensure that your code is always matching those rules

Examples :

• All our events must reside in the events package
• Our repository layer can only be accessed through our application layer
• …

Concepts - What is it?

You can use the slides available here for this part

Concrete Practice - Create some rules

To simplify the usage of the library during this kata some preparation work has already been made:

• Dependencies are already there: TngTech.ArchUnitNet and TngTech.ArchUnitNet.xUnit
• ArchUnitExtensions contains some extensions that could help you to check rules
• Test classes have been provided but implementations are missing
  • You have to fill the gap to implement the rule expressed in plain text english correctly
    • Do it for each rule using the EmptyRule
  • If you want, you can fix the production code based on the ArchRule discoveries - Optional

Example

public class Guidelines
{
    [Fact]
    public void ClassShouldNotDependOnAnother() =>
        EmptyRule("Class SomeExample should not depend on Other")
            .Check();
}

• We use the ArchUnit dsl to write it
  • Let the public api guide you
  • Think dot-driven development

[Fact]
public void ClassShouldNotDependOnAnother() =>
    Classes().That()
        .Are(typeof(SomeExample))
        .Should()
        .NotDependOnAny(typeof(Other))
        .Check();

Exercises

Recommended order (do at least 1 per category / test class):

• LayeredArchitecture
• NamingConvention
• Guidelines
• LinguisticAntiPatterns
• MethodsReturnTypes
• Annotations

Which other rules could be added?

Solution is available in the solution folder

Conclusion - Reflect

• What can we do with it ?
• Which rules could be useful ?

Resources

• ArchUnit
• ArchUnit for .Net