Layers

Layer configuration allows you to define architectural levels of your project and enforce dependency rules between them.

Defining Layers

Layers are configured inside the layer_violation rule. Each layer definition consists of:

• name: Unique name of the layer.
• path (or paths): Glob pattern identifying files in this layer.
• allowed_imports (or can_import): List of layer names that this layer is allowed to import.

Example: Clean Architecture

rules:
  layer_violation:
    severity: high
    layers:
      - name: domain
        path: '**/domain/**'
        allowed_imports: [] # Domain layer should not depend on anything

      - name: application
        path: '**/application/**'
        allowed_imports:
          - domain

      - name: infrastructure
        path: '**/infrastructure/**'
        allowed_imports:
          - domain
          - application

      - name: presentation
        path: '**/presentation/**'
        allowed_imports:
          - domain
          - application

How It Works

When the layer_violation detector is enabled:

1. It maps every file in your project to a specific layer based on the path pattern.
2. If a file matches multiple patterns, the most specific one (longest pattern) is chosen.
3. The tool checks every import. If a file in layer A imports a file in layer B, but B is not in the allowed_imports list of layer A, a violation is reported.