9. Developer Guide

Cluster Genesis development is overseen by a team of IBM engineers.

9.1. Git Repository Model

Development and test is orchestrated within the master branch. Stable release-x.y branches are created off master and supported with bug fixes. Semantic Versioning is used for release tags and branch names.

9.2. Coding Style

Code should be implemented in accordance with PEP 8 – Style Guide for Python Code.

It is requested that modules contain appropriate __future__ imports to simplify future migration to Python3.

9.3. Commit Message Rules

  • Subject line

    • First line of commit message provides a short description of change

    • Must not exceed 50 characters

    • First word after tag must be capitalized

    • Must begin with one of the follwoing subject tags:

      feat:      New feature
fix:       Bug fix
docs:      Documentation change
style:     Formatting change
refactor:  Code change without new feature
test:      Tests change
chore:     Miscellaneous no code change
Revert     Revert previous commit
  • Body
    • Single blank line seperates subject line and message body
    • Contains detailed description of change
    • Lines must not exceed 72 characters
    • Periods must be followed by single space

Your Commit message can be validated within the tox environment (see below for setup of the tox environment):

cluster-genesis$ tox -e commit-message-validate

9.4. Unit Tests and Linters

9.4.1. Tox

Tox is used to manage python virtual environments used to run unit tests and various linters.

To run tox first install python dependencies:

cluster-genesis$ ./scripts/install.sh

Install tox:

cluster-genesis$ pip install tox

To run all tox test environments:

cluster-genesis$ tox

List test environments:

cluster-genesis$ tox -l
py27
bashate
flake8
ansible-lint
commit-message-validate
verify-copyright
file-format

Run only ‘flake8’ test environment:

cluster-genesis$ tox -e flake8

9.4.2. Unit Test

Unit test scripts reside in the cluster-genesis/tests/unit/ directory.

Unit tests can be run through tox:

cluster-genesis$ tox -e py27

Or called directly through python (be mindful of your python environment!):

cluster-genesis$ python -m unittest discover

9.4.3. Linters

Linters are required to run cleanly before a commit is submitted. The following linters are used:

  • Bash: bashate
  • Python: pycodestyle/flake8/pylint
  • Ansible: ansible-lint

Linters can be run through tox:

cluster-genesis$ tox -e bashate
cluster-genesis$ tox -e flake8
cluster-genesis$ tox -e ansible-lint

Or called directly (again, be mindful of your python environment!)

Pylint and pycodestyle validation is not automatically launched when issuing the tox command. They need to be called out explicitly:

cluster-genesis$ tox -e pycodestyle
cluster-genesis$ tox -e pylint
cluster-genesis$ tox -e pylint-errors

9.4.4. File Format Validation

Ensure that each text file is in unix mode where lines are terminated by a linefeed:

cluster-genesis$ tox -e file-format