layer-linter 0.7.2

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

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.yml 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.yml 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

History

0.1.0 (2018-06-20)

• First release on PyPI.

0.2.0 (2018-06-23)

• Look for layers.yml in current working directory.

0.3.0 (2018-06-24)

• Rename command to layer-lint.

• Changed order of layers in layers.yml to be listed high level to low level.

0.4.0 (2018-07-22)

• Made dependency analysis more efficient and robust.

• Improved report formatting.

• Removed illegal dependencies that were implied by other, more succinct illegal dependencies.

• Added --debug command line argument.

0.5.0 (2018-08-01)

• Added count of analysed files and dependencies to report.

• Fixed issues from running command in a different directory to the package.

• Increased speed of analysis.

• Changed --config_directory command line argument to --config-directory.

0.6.0 (2018-08-07)

• Added ability to whitelist paths.

0.6.1 (2018-08-07)

• Add current working directory to path.

0.6.2 (2018-08-17)

• Don’t analyse children of directories that aren’t Python packages.

• Prevented installing incompatible version of Pydeps (1.6).

0.7.0 (2018-09-04)

• Complete rewrite of static analysis used to build dependency graph.

• Added quiet and verbose reporting.

• Added type annotation and mypy.

• Build earlier versions of Python using pybackwards.

• Corrected docs to refer to layers.yml instead of layers.yaml.

0.7.1 (2018-09-04)

• Fix packaging bug with 0.7.0.

latest

• Fix bug with not checking all submodules of layer.