qemu-e2k/python
Daniel P. Berrangé 439125293c python: introduce qmp-shell-wrap convenience tool
With the current 'qmp-shell' tool developers must first spawn QEMU with
a suitable -qmp arg and then spawn qmp-shell in a separate terminal
pointing to the right socket.

With 'qmp-shell-wrap' developers can ignore QMP sockets entirely and
just pass the QEMU command and arguments they want. The program will
listen on a UNIX socket and tell QEMU to connect QMP to that.

For example, this:

 # qmp-shell-wrap -- qemu-system-x86_64 -display none

Is roughly equivalent of running:

 # qemu-system-x86_64 -display none -qmp qmp-shell-1234 &
 # qmp-shell qmp-shell-1234

Except that 'qmp-shell-wrap' switches the socket peers around so that
it is the UNIX socket server and QEMU is the socket client. This makes
QEMU reliably go away when qmp-shell-wrap exits, closing the server
socket.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20220128161157.36261-2-berrange@redhat.com
[Edited for rebase. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2022-02-23 17:07:26 -05:00
..
qemu python: introduce qmp-shell-wrap convenience tool 2022-02-23 17:07:26 -05:00
tests python: Add iotest linters to test suite 2021-11-01 11:54:59 -04:00
.gitignore python/aqmp: Add Coverage.py support 2021-09-27 12:10:29 -04:00
avocado.cfg python: use avocado's "new" runner 2022-01-21 16:01:13 -05:00
Makefile python: pin setuptools below v60.0.0 2022-01-21 16:01:09 -05:00
MANIFEST.in
PACKAGE.rst
Pipfile
Pipfile.lock python: upgrade mypy to 0.780 2022-02-02 14:12:22 -05:00
README.rst python: move qmp-shell under the AQMP package 2022-01-21 16:01:31 -05:00
setup.cfg python: introduce qmp-shell-wrap convenience tool 2022-02-23 17:07:26 -05:00
setup.py
VERSION

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``. 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 want the first invocation above.

If you append the ``--editable`` or ``-e`` argument to either invocation
above, pip will install in "editable" mode. This installs the package as
a forwarder ("qemu.egg-link") that points to the source tree. In so
doing, the installed package always reflects the latest version in your
source tree.

Installing ".[devel]" instead of "." will additionally pull in required
packages for testing this package. They are not runtime requirements,
and are not needed to simply use these libraries.

Running ``make develop`` will pull in all testing dependencies and
install QEMU in editable mode to the current environment.
(It is a shortcut for ``pip3 install -e .[devel]``.)

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


Using these packages without installing them
--------------------------------------------

These packages may be used without installing them first, by using one
of two tricks:

1. Set your PYTHONPATH environment variable to include this source
   directory, e.g. ``~/src/qemu/python``. See
   https://docs.python.org/3/using/cmdline.html#envvar-PYTHONPATH

2. Inside a Python script, use ``sys.path`` to forcibly include a search
   path prior to importing the ``qemu`` namespace. See
   https://docs.python.org/3/library/sys.html#sys.path

A strong downside to both approaches is that they generally interfere
with static analysis tools being able to locate and analyze the code
being imported.

Package installation also normally provides executable console scripts,
so that tools like ``qmp-shell`` are always available via $PATH. To
invoke them without installation, you can invoke e.g.:

``> PYTHONPATH=~/src/qemu/python python3 -m qemu.aqmp.qmp_shell``

The mappings between console script name and python module path can be
found in ``setup.cfg``.


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

- ``qemu/`` Python 'qemu' namespace package source directory.
- ``tests/`` Python package tests directory.
- ``avocado.cfg`` Configuration for the Avocado test-runner.
  Used by ``make check`` et al.
- ``Makefile`` provides some common testing/installation invocations.
  Try ``make help`` to see available targets.
- ``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 check-pipenv``.
- ``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.