edugomez / layer_linter

Layer Linter checks that your project follows a layered architecture that you define.

Layer Linter

Layer Linter checks that your project follows a custom-defined layered architecture.

• Free software: BSD license
• Documentation: https://layer-linter.readthedocs.io.

Overview

Layer Linter can be used as part of an automated test suite to check that you are following a self-imposed layered architecture within your Python project. This is particularly useful if you are working on a complex codebase within a team, when you want to enforce a particular architectural style.

To define how layers work within your project, you create a layers.yaml file. This file prescribes the order in which different modules within your project may import from each other.

Running the layer-lint command will parse the file, analyse your project's internal dependencies within your project, and error if you are violating your prescribed architecture.

Quick start

Install Layer Linter:

pip install layer-linter

Create a layers.yaml in the root of your project, in this format:

My Layers Contract:
  packages:
    - myproject.packageone
    - myproject.packagetwo
    - myproject.packagethree
  layers:
    - highlevelmodule
    - mediumlevelmodule
    - lowlevelmodule

From your project root, run:

layer-lint myproject

If your code violates the contract, you will see an error message as follows:

============
Layer Linter
============

---------
Contracts
---------

Analyzed 23 files, 44 dependencies.
-----------------------------------

My layer contract BROKEN

Contracts: 0 kept, 1 broken.

----------------
Broken contracts
----------------


My layer contract
-----------------


1. myproject.packagetwo.lowlevelmodule imports myproject.packagetwo.highlevelmodule:

    myproject.packagetwo.lowlevelmodule <-
    myproject.utils <-
    myproject.packagetwo.highlevelmodule