The ``tox.ini`` file has a number of top level sections defined by ``[ ]`` and subsections within those. For complete documentation
on all subsections inside of a tox section please refer to the tox documentation.
*``tox`` : This section contains the ``envlist`` which is used to create our dynamic matrix. Refer to the `section here <http://tox.readthedocs.io/en/latest/config.html#generating-environments-conditional-settings>`_ for more information on how the ``envlist`` works.
*``purge`` : This section contains commands that only run for scenarios that purge the cluster and redeploy. You'll see this section being reused in ``testenv``
with the following syntax: ``{[purge]commands}``
*``update`` : This section contains commands taht only run for scenarios that deploy a cluster and then upgrade it to another ceph version.
*``testenv`` : This is the main section of the ``tox.ini`` file and is run on every scenario. This section contains many *factors* that define conditional
settings depending on the scenarios defined in the ``envlist``. For example, the factor ``centos7_cluster`` in the ``changedir`` subsection of ``testenv`` sets
the directory that tox will change do when that factor is selected. This is an important behavior that allows us to use the same ``tox.ini`` and reuse commands while
The tox environments are controlled by the ``envlist`` subsection of the ``[tox]`` section. Anything inside of ``{}`` is considered a *factor* and will be included
in the dynamic matrix that tox creates. Inside of ``{}`` you can include a comma separated list of the *factors*. Do not use a hyphen (``-``) as part
of the *factor* name as those are used by tox as the separator between different factor sets.
For example, if wanted to add a new test *factor* for the next ceph release of luminious this is how you'd accomplish that. Currently, the first factor set in our ``envlist``
is used to define the ceph release (``{jewel,kraken,rhcs}-...``). To add luminous you'd change that to look like ``{luminous,kraken,rhcs}-...``. In the ``testenv`` section
this is a subsection called ``setenv`` which allows you to provide environment variables to the tox environment and we support an environment variable called ``CEPH_STABLE_RELEASE``. To ensure that all the new tests that are created by adding the luminous *factor* you'd do this in that section: ``luminous: CEPH_STABLE_RELEASE=luminous``.