python-openstackclient/doc/source/contributor/developing.rst

===============================
Developing with OpenStackClient
===============================

Communication
-------------

IRC Channel
~~~~~~~~~~~

The OpenStackClient team doesn't have regular meetings so if you have
questions or anything you want to discuss, come to our channel:
#openstack-sdks


Testing
-------

Tox prerequisites and installation
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Install the prerequisites for Tox:

* On Ubuntu or Debian:

  .. code-block:: bash

    $ apt-get install gcc gettext python3-dev libxml2-dev libxslt1-dev \
      zlib1g-dev

  You may need to use pip install for some packages.

* On RHEL or CentOS including Fedora:

  .. code-block:: bash

    $ yum install gcc python3-devel libxml2-devel libxslt-devel

* On openSUSE or SUSE linux Enterprise:

  .. code-block:: bash

    $ zypper install gcc python3-devel libxml2-devel libxslt-devel

Install python-tox:

.. code-block:: bash

    $ pip install tox

To run the full suite of tests maintained within OpenStackClient.

.. code-block:: bash

    $ tox

.. NOTE::

    The first time you run ``tox``, it will take additional time to build
    virtualenvs. You can later use the ``-r`` option with ``tox`` to rebuild
    your virtualenv in a similar manner.

To run tests for one or more specific test environments (for example, the most
common configuration of the latest Python version and PEP-8), list the
environments with the ``-e`` option, separated by spaces:

.. code-block:: bash

    $ tox -e py38,pep8

See ``tox.ini`` for the full list of available test environments.

Running functional tests
~~~~~~~~~~~~~~~~~~~~~~~~

OpenStackClient also maintains a set of functional tests that are optimally
designed to be run against OpenStack's gate. Optionally, a developer may
choose to run these tests against any OpenStack deployment, however depending
on the services available, results vary.

To run the entire suite of functional tests:

.. code-block:: bash

    $ tox -e functional

To run a specific functional test:

.. code-block:: bash

    $ tox -e functional -- --regex tests.functional.compute.v2.test_server

Running with PDB
~~~~~~~~~~~~~~~~

Using PDB breakpoints with ``tox`` and ``testr`` normally does not work since
the tests fail with a `BdbQuit` exception rather than stopping at the
breakpoint.

To run with PDB breakpoints during testing, use the ``debug`` ``tox``
environment. For example, passing a test name since you will normally only want
to run the test that hits your breakpoint:

.. code-block:: bash

    $ tox -e debug openstackclient.tests.identity.v3.test_group

For reference, the `debug`_ ``tox`` environment implements the instructions

.. _`debug`: https://wiki.openstack.org/wiki/Testr#Debugging_.28pdb.29_Tests


Coding Style
------------

OpenStackClient uses `flake8`__ along with `hacking`__, an OpenStack-specific
superset of ``flake8`` rules, to enforce coding style. This can be run manually
using ``tox``:

.. code-block:: bash

    $ tox -e pep8

Alternatively, you can use the `pre-commit framework`__ to allow running of
some linters on each commit. This must be enabled locally to function:

.. code-block:: bash

    $ pip install --user pre-commit
    $ pre-commit install --allow-missing-config

.. __: https://flake8.pycqa.org/en/latest/
.. __: https://docs.openstack.org/hacking/latest/user/hacking.html
.. __: https://pre-commit.com/


Documentation
-------------

The documentation is generated with Sphinx using the ``tox`` command. To
create HTML docs, run the commands:

.. code-block:: bash

    $ tox -e docs

The resultant HTML will be in the ``doc/build/html`` directory.


Release Notes
-------------

The release notes for a patch should be included in the patch.  See the
`Project Team Guide`_ for more information on using reno in OpenStack.

.. _`Project Team Guide`: http://docs.openstack.org/project-team-guide/release-management.html#managing-release-notes

If any of the following applies to the patch, a release note is required:

* The deployer needs to take an action when upgrading
* The plugin interface changes
* A new feature is implemented
* A command or option is removed
* Current behavior is changed
* A security bug is fixed

Reno is used to generate release notes. Use the commands:

.. code-block:: bash

    $ tox -e venv -- reno new <bug-,bp-,whatever>

Then edit the sample file that was created and push it with your change.

To run the commands and see results:

.. code-block:: bash

    $ git commit  # Commit the change because reno scans git log.

    $ tox -e releasenotes

At last, look at the generated release notes files in ``releasenotes/build/html`` in your browser.


Testing new code
----------------

If a developer wants to test new code (feature, command or option) that
they have written, OpenStackClient may be installed from source by running
the following commands in the base directory of the project:

.. code-block:: bash

   $ python setup.py develop

or

.. code-block:: bash

   $ pip install -e .

Standardize Import Format
~~~~~~~~~~~~~~~~~~~~~~~~~

More information about Import Format, see `Import Order Guide
<https://docs.openstack.org/hacking/latest/user/hacking.html#imports>`__.

The import order shows below:

.. code-block:: none

   {{stdlib imports in human alphabetical order}}
   \n
   {{third-party lib imports in human alphabetical order}}
   \n
   {{project imports in human alphabetical order}}
   \n
   \n
   {{begin your code}}

Example
^^^^^^^

.. code-block:: python

    import copy
    import fixtures
    import os

    from osc_lib.api import auth
    from osc_lib import utils

    from openstackclient import shell
    from openstackclient.tests import utils
    from unittest import mock