Validate Structure

The validateStructure | vs Validate that project references aren't violated.

   gradle validateStructure
   gradle vs

This validation has another best practices verifications, which you can see on the generated ArchitectureTest file within the unit tests of the app-service module.

Dependency Rules

One important point made by Robert C. Martin on Clean Architecture is the Dependency Rule, that can be summarized like this: source code dependencies can only point inwards. Nothing in an inner circle can know anything at all about something in an outer circle. In particular, the name of something declared in an outer circle must not be mentioned by the code in an inner circle.

Having that in mind, the validateStructure | vs task performs the following validations:

Model module: to have no dependencies at all.
UseCase module: to declare dependency to the Model module ONLY, and no other additional dependencies.
Infrastructure Layer modules:
- Allow declaration of any external dependency.
- Allow declaration of dependency on Model and/or UseCase modules.
- Avoid declaration of dependency AppService module.

Whitelisting dependencies:

Some dependencies, specially when working with BOMs (Bills of Materials), are injected transversally to the project, making the validation task to flag failures to rules 1 and 2. To avoid this scenario, or other you may encounter, you can configure a set of whitelisted dependencies.

Example:

Let's say you have declared a BOM in your project:

dependencies {
  implementation(platform("com.myorg:my-bom:0.0.1"))
}

This will make validateStructure | vs to flag a failure indicating an error like this:

Validating Model Module
 --- Dependency com.myorg:some-bom is not allowed in Model Layer

To avoid this, you can white list your BOM like this:

// build.gradle
cleanPlugin {
  modelProps {
     whitelistedDependencies = "my-bom, <dep2>, <depN..>"
  }
}

Indicating only the name of the dependencies comma-separated.

Dependency Rules​

Dependency Rules