qemu/python
John Snow 41c1d81cf2 python: Add pipenv support
pipenv is a tool used for managing virtual environments with pinned,
explicit dependencies. It is used for precisely recreating python
virtual environments.

pipenv uses two files to do this:

(1) Pipfile, which is similar in purpose and scope to what setup.cfg
lists. It specifies the requisite minimum to get a functional
environment for using this package.

(2) Pipfile.lock, which is similar in purpose to `pip freeze >
requirements.txt`. It specifies a canonical virtual environment used for
deployment or testing. This ensures that all users have repeatable
results.

The primary benefit of using this tool is to ensure *rock solid*
repeatable CI results with a known set of packages. Although I endeavor
to support as many versions as I can, the fluid nature of the Python
toolchain often means tailoring code for fairly specific versions.

Note that pipenv is *not* required to install or use this module; this is
purely for the sake of repeatable testing by CI or developers.

Here, a "blank" pipfile is added with no dependencies, but specifies
Python 3.6 for the virtual environment.

Pipfile will specify our version minimums, while Pipfile.lock specifies
an exact loadout of packages that were known to operate correctly. This
latter file provides the real value for easy setup of container images
and CI environments.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-15-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
..
qemu python: add directory structure README.rst files 2021-06-01 16:21:21 -04:00
.isort.cfg python: create qemu packages 2021-06-01 16:21:21 -04:00
MANIFEST.in python: add MANIFEST.in 2021-06-01 16:21:21 -04:00
mypy.ini python: add mypy config 2020-10-20 09:37:57 -04:00
PACKAGE.rst python: add qemu package installer 2021-06-01 16:21:21 -04:00
Pipfile python: Add pipenv support 2021-06-01 16:21:21 -04:00
README.rst python: Add pipenv support 2021-06-01 16:21:21 -04:00
setup.cfg python: add VERSION file 2021-06-01 16:21:21 -04:00
setup.py python: add qemu package installer 2021-06-01 16:21:21 -04:00
VERSION python: add VERSION file 2021-06-01 16:21:21 -04:00

QEMU Python Tooling
===================

This directory houses Python tooling used by the QEMU project to build,
configure, and test QEMU. It is organized by namespace (``qemu``), and
then by package (e.g. ``qemu/machine``, ``qemu/qmp``, etc).

``setup.py`` is used by ``pip`` to install this tooling to the current
environment. ``setup.cfg`` provides the packaging configuration used by
``setup.py`` in a setuptools specific format. You will generally invoke
it by doing one of the following:

1. ``pip3 install .`` will install these packages to your current
   environment. If you are inside a virtual environment, they will
   install there. If you are not, it will attempt to install to the
   global environment, which is **not recommended**.

2. ``pip3 install --user .`` will install these packages to your user's
   local python packages. If you are inside of a virtual environment,
   this will fail; you likely want the first invocation above.

If you append the ``-e`` argument, pip will install in "editable" mode;
which installs a version of the package that installs a forwarder
pointing to these files, such that the package always reflects the
latest version in your git tree.

See `Installing packages using pip and virtual environments
<https://packaging.python.org/guides/installing-using-pip-and-virtual-environments/>`_
for more information.


Files in this directory
-----------------------

- ``qemu/`` Python package source directory.
- ``MANIFEST.in`` is read by python setuptools, it specifies additional files
  that should be included by a source distribution.
- ``PACKAGE.rst`` is used as the README file that is visible on PyPI.org.
- ``Pipfile`` is used by Pipenv to generate ``Pipfile.lock``.
- ``Pipfile.lock`` is a set of pinned package dependencies that this package
  is tested under in our CI suite. It is used by ``make venv-check``.
- ``README.rst`` you are here!
- ``VERSION`` contains the PEP-440 compliant version used to describe
  this package; it is referenced by ``setup.cfg``.
- ``setup.cfg`` houses setuptools package configuration.
- ``setup.py`` is the setuptools installer used by pip; See above.