Commit Graph

11 Commits

Author SHA1 Message Date
John Snow 3c8de38c85 python: add tox support
This is intended to be a manually run, non-CI script.

Use tox to test the linters against all python versions from 3.6 to
3.10. This will only work if you actually have those versions installed
locally, but Fedora makes this easy:

> sudo dnf install python3.6 python3.7 python3.8 python3.9 python3.10

Unlike the pipenv tests (make venv-check), this pulls "whichever"
versions of the python packages, so they are unpinned and may break as
time goes on. In the case that breakages are found, setup.cfg should be
amended accordingly to avoid the bad dependant versions, or the code
should be amended to work around the issue.

With confidence that the tests pass on 3.6 through 3.10 inclusive, add
the appropriate classifiers to setup.cfg to indicate which versions we
claim to support.

Tox 3.18.0 or above is required to use the 'allowlist_externals' option.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-31-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 31622b2a8a python: add avocado-framework and tests
Try using avocado to manage our various tests; even though right now
they're only invoking shell scripts and not really running any
python-native code.

Create tests/, and add shell scripts which call out to mypy, flake8,
pylint and isort to enforce the standards in this directory.

Add avocado-framework to the setup.cfg development dependencies, and add
avocado.cfg to store some preferences for how we'd like the test output
to look.

Finally, add avocado-framework to the Pipfile environment and lock the
new dependencies. We are using avocado >= 87.0 here to take advantage of
some features that Cleber has helpfully added to make the test output
here *very* friendly and easy to read for developers that might chance
upon the output in Gitlab CI.

[Note: ALL of the dependencies get updated to the most modern versions
that exist at the time of this writing. No way around it that I have
seen. Not ideal, but so it goes.]

Provided you have the right development dependencies (mypy, flake8,
isort, pylint, and now avocado-framework) You should be able to run
"avocado --config avocado.cfg run tests/" from the python folder to run
all of these linters with the correct arguments.

(A forthcoming commit adds the much easier 'make check'.)

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-28-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow dbe75f5566 python: add devel package requirements to setuptools
setuptools doesn't have a formal understanding of development requires,
but it has an optional feataures section. Fine; add a "devel" feature
and add the requirements to it.

To avoid duplication, we can modify pipenv to install qemu[devel]
instead. This enables us to run invocations like "pip install -e
.[devel]" and test the package on bleeding-edge packages beyond those
specified in Pipfile.lock.

Importantly, this also allows us to install the qemu development
packages in a non-networked mode: `pip3 install --no-index -e .[devel]`
will now fail if the proper development dependencies are not already
met. This can be useful for automated build scripts where fetching
network packages may be undesirable.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-27-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 158ac451b9 python: move .isort.cfg into setup.cfg
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-24-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 0542a4c957 python: add mypy to pipenv
0.730 appears to be about the oldest version that works with the
features we want, including nice human readable output (to make sure
iotest 297 passes), and type-parameterized Popen generics.

0.770, however, supports adding 'strict' to the config file, so require
at least 0.770.

Now that we are checking a namespace package, we need to tell mypy to
allow PEP420 namespaces, so modify the mypy config as part of the move.

mypy can now be run from the python root by typing 'mypy -p qemu'.

A note on mypy invocation: Running it as "mypy qemu/" changes the import
path detection mechanisms in mypy slightly, and it will fail. See
https://github.com/python/mypy/issues/8584 for a decent entry point with
more breadcrumbs on the various behaviors that contribute to this subtle
difference.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-23-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow e941c844e4 python: move mypy.ini into setup.cfg
mypy supports reading its configuration values from a central project
configuration file; do so.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-22-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 21d0b86679 python: add excluded dirs to flake8 config
Instruct flake8 to avoid certain well-known directories created by
python tooling that it ought not check.

Note that at-present, nothing actually creates a ".venv" directory; but
it is in such widespread usage as a de-facto location for a developer's
virtual environment that it should be excluded anyway. A forthcoming
commit canonizes this with a "make venv" command.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-20-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 81f8c4467c python: move flake8 config to setup.cfg
Update the comment concerning the flake8 exception to match commit
42c0dd12, whose commit message stated:

A note on the flake8 exception: flake8 will warn on *any* bare except,
but pylint's is context-aware and will suppress the warning if you
re-raise the exception.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-19-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow ef42440d79 python: move pylintrc into setup.cfg
Delete the empty settings now that it's sharing a home with settings for
other tools.

pylint can now be run from this folder as "pylint qemu".

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-17-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 3afc32906f python: add VERSION file
Python infrastructure as it exists today is not capable reliably of
single-sourcing a package version from a parent directory. The authors
of pip are working to correct this, but as of today this is not possible.

The problem is that when using pip to build and install a python
package, it copies files over to a temporary directory and performs its
build there. This loses access to any information in the parent
directory, including git itself.

Further, Python versions have a standard (PEP 440) that may or may not
follow QEMU's versioning. In general, it does; but naturally QEMU does
not follow PEP 440. To avoid any automatically-generated conflict, a
manual version file is preferred.

I am proposing:

- Python tooling follows the QEMU version, indirectly, but with a major
  version of 0 to indicate that the API is not expected to be
  stable. This would mean version 0.5.2.0, 0.5.1.1, 0.5.3.0, etc.

- In the event that a Python package needs to be updated independently
  of the QEMU version, a pre-release alpha version should be preferred,
  but *only* after inclusion to the qemu development or stable branches.

  e.g. 0.5.2.0a1, 0.5.2.0a2, and so on should be preferred prior to
  5.2.0's release.

- The Python core tooling makes absolutely no version compatibility
  checks or constraints. It *may* work with releases of QEMU from the
  past or future, but it is not required to.

  i.e., "qemu.machine" will, for now, remain in lock-step with QEMU.

- We reserve the right to split the qemu package into independently
  versioned subpackages at a later date. This might allow for us to
  begin versioning QMP independently from QEMU at a later date, if
  we so choose.

Implement this versioning scheme by adding a VERSION file and setting it
to 0.6.0.0a1.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-12-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow ea1213b7cc python: add qemu package installer
Add setup.cfg and setup.py, necessary for installing a package via
pip. Add a ReST document (PACKAGE.rst) explaining the basics of what
this package is for and who to contact for more information. This
document will be used as the landing page for the package on PyPI.

List the subpackages we intend to package by name instead of using
find_namespace because find_namespace will naively also packages tests,
things it finds in the dist/ folder, etc. I could not figure out how to
modify this behavior; adding allow/deny lists to setuptools kept
changing the packaged hierarchy. This works, roll with it.

I am not yet using a pyproject.toml style package manifest, because
"editable" installs are not defined (yet?) by PEP-517/518.

I consider editable installs crucial for development, though they have
(apparently) always been somewhat poorly defined.

Pip now (19.2 and later) now supports editable installs for projects
using pyproject.toml manifests, but might require the use of the
--no-use-pep517 flag, which somewhat defeats the point. Full support for
setup.py-less editable installs was not introduced until pip 21.1.1:
7a95720e79

For now, while the dust settles, stick with the de-facto
setup.py/setup.cfg combination supported by setuptools. It will be worth
re-evaluating this point again in the future when our supported build
platforms all ship a fairly modern pip.

Additional reading on this matter:

https://github.com/pypa/packaging-problems/issues/256
https://github.com/pypa/pip/issues/6334
https://github.com/pypa/pip/issues/6375
https://github.com/pypa/pip/issues/6434
https://github.com/pypa/pip/issues/6438

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-11-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00