OpenStack Hacking Style Checks. Mirror of code maintained at opendev.org.
hacking is a set of flake8 plugins that test and enforce the
Hacking pins its dependencies, as a new release of some dependency can break hacking based gating jobs. This is because new versions of dependencies can introduce new rules, or make existing rules stricter.
hacking is available from pypi, so just run::
pip install hacking
This will install specific versions of
Hacking started its life out as a text file in Nova's first commit. It was initially based on the
Google Python Style Guide_, and over time more OpenStack specific rules were added. Hacking serves several purposes:
Initially the hacking style guide was enforced manually by reviewers, but this was a big waste of time so hacking, the tool, was born to automate the process and remove the extra burden from human reviewers.
Google Python Style Guide: https://google.github.io/styleguide/pyguide.html
hacking uses the
major.minor.maintenancerelease notation, where maintenance releases cannot contain new checks. This way projects can gate on hacking by pinning on the
major.minornumber while accepting maintenance updates without being concerned that a new version will break the gate with a new check.
For example a project can depend on
hacking>=0.10.0,<0.11.0, and can know that
0.10.1will not fail in places where
Each check is a pep8 plugin so read
The focus of new or changed rules should be to do one of the following
But, as always, remember that these are Guidelines. Treat them as such. There are always times for exceptions. All new rules should support noqa.
If a check needs to be staged in, or it does not apply to every project or its branch, it can be added as off by default.
StyleGuide_, and hacking just enforces them; so when adding a new check, it must be in
Some of the available checks are disabled by default. These checks are:
To enable these checks, edit the
flake8section of the
tox.inifile. For example to enable H106 and H203:
.. code-block:: ini
[flake8] enable-extensions = H106,H203
hacking supports having local changes in a source tree. They need to be registered individually in tox.ini:
Add to tox.ini a new section
flake8:local-pluginsand list each plugin with its entry-point. Additionally, you can add the path to the files containing the plugins so that the repository does not need to be installed with the
.. code-block:: ini
[flake8:local-plugins] extension = N307 = checks:importnodbinvirt N325 = checks:CheckForStrUnicodeExc paths = ./nova/hacking
The plugins, in the example above they live in
nova/hacking/checks.py, need to annotate all functions with
.. code-block:: python
from hacking import core ... @core.flake8ext def importnodbinvirt(logical_line, filename): ...
class CheckForStrUnicodeExc(BaseASTChecker): name = "checkforstrunicodeexc" version = "1.0" ...
Further details are part of the