importlib.metadata is included in Python 3.8, so there is no
need to fallback to either importlib-metadata or pkgresources
when generating console script shims.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Debian 10 is not anymore a supported distro, since Debian 12 was
released on June 10, 2023. Our supported build platforms as of today
all support at least 3.8 (and all of them except for Ubuntu 20.04
support 3.9):
openSUSE Leap 15.5: 3.6.15 (3.11.2)
CentOS Stream 8: 3.6.8 (3.8.13, 3.9.16, 3.11.4)
CentOS Stream 9: 3.9.17 (3.11.4)
Fedora 37: 3.11.4
Fedora 38: 3.11.4
Debian 11: 3.9.2
Debian 12: 3.11.2
Alpine 3.14, 3.15: 3.9.16
Alpine 3.16, 3.17: 3.10.10
Ubuntu 20.04 LTS: 3.8.10
Ubuntu 22.04 LTS: 3.10.12
NetBSD 9.3: 3.9.13*
FreeBSD 12.4: 3.9.16
FreeBSD 13.1: 3.9.18
OpenBSD 7.2: 3.9.17
Note: NetBSD does not appear to have a default meta-package, but offers
several options, the lowest of which is 3.7.15. However, "python39"
appears to be a pre-requisite to one of the other packages we request
in tests/vm/netbsd.
Since it is safe under our supported platform policy, bump our
minimum supported version of Python to 3.8. The two most interesting
features to have by default include:
- the importlib.metadata module, whose lack is responsible for over 100
lines of code in mkvenv.py
- improvements to asyncio, for example asyncio.CancelledError
inherits from BaseException rather than Exception
In addition, code can now use the assignment operator ':='
Because mypy now learns about importlib.metadata, a small change to
mkvenv.py is needed to pass type checking.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit e8e4298fea.
ensuregroup allows to specify both the acceptable versions of avocado,
and a locked version to be used when avocado is not installed as a system
pacakge. This lets us install avocado in pyvenv/ using "mkvenv.py" and
reuse the distro package on Fedora and CentOS Stream (the only distros
where it's available).
ensuregroup's usage of "(>=..., <=...)" constraints when evaluating
the distro package, and "==" constraints when installing it from PyPI,
makes it possible to avoid conflicts between the known-good version and
a package plugins included in the distro.
This is because package plugins have "==" constraints on the version
that is included in the distro, and, using "pip install avocado==88.1"
on a venv that includes system packages will result in an error:
avocado-framework-plugin-varianter-yaml-to-mux 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.
avocado-framework-plugin-result-html 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.
But at the same time, if the venv does not include a system distribution
of avocado then we can install a known-good version and stick to LTS
releases.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1663
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce a new subcommand that retrieves the packages to be installed
from a TOML file. This allows being more flexible in using the system
version of a package, while at the same time using a known-good version
when installing the package. This is important for packages that
sometimes have backwards-incompatible changes or that depend on
specific versions of their dependencies.
Compared to JSON, TOML is more human readable and easier to edit. A
parser is available in 3.11 but also available as a small (12k) package
for older versions, tomli. While tomli is bundled with pip, this is only
true of recent versions of pip. Of all the supported OSes pretty much
only FreeBSD has a recent enough version of pip while staying on Python
<3.11. So we cannot use the same trick that is in place for distlib.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We would like to place all Python dependencies in the same file, so that
we can add more information without having long and complex command lines.
The plan is to have a TOML file with one entry per package, for example
[avocado]
avocado-framework = {
accepted = "(>=88.1, <93.0)",
installed = "88.1",
canary = "avocado"
}
Each TOML section will thus be a dictionary of dictionaries. Modify
mkvenv.py's workhorse function, _do_ensure, to already operate on such
a data structure. The "ensure" subcommand is modified to separate the
depspec into a name and a version part, and use the result (plus the
--diagnose argument) to build a dictionary for each command line argument.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the matching between the "absent" array and dep_specs[0] inside
the loop, preparing for the possibility of having multiple canaries
among the installed packages.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let pip decide whether a new version should be installed or the current
one is okay. This ensures that the virtual environment is updated
(either upgraded or downgraded) whenever a new version of a package is
requested.
The hardest part here is figuring out if a package is installed in
the venv (which also has to be done twice to account for the presence
of either setuptools in Python <3.8, or importlib in Python >=3.8).
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Cc: John Snow <jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If sphinx is present but the theme is not, mkvenv will print an
inaccurate diagnostic:
ERROR: Could not find a version that satisfies the requirement sphinx-rtd-theme>=0.5.0 (from versions: none)
ERROR: No matching distribution found for sphinx-rtd-theme>=0.5.0
'sphinx>=1.6.0' not found:
• Python package 'sphinx' version '5.3.0' was found, but isn't suitable.
• mkvenv was configured to operate offline and did not check PyPI.
Instead, ignore the packages that were found to be present, and report
an error based on the first absent package.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
importlib.metadata is just as good as distlib.database and a bit more
battle-proven for "egg" based distributions, and in fact that is exactly
why mkvenv.py is not using distlib.database to find entry points: it
simply does not work for eggs.
The only disadvantage of importlib.metadata is that it is not available
by default before Python 3.8, so we need a fallback to pkg_resources
(again, just like for the case of finding entry points). Do so to
fix issues where incorrect egg metadata results in a JSONDecodeError.
While at it, reuse the new _get_version function to diagnose an incorrect
version of the package even if importlib.metadata is not available.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is only available in Python 3.7+.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-26-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is a workaround intended for Debian 10, where the debian-patched
pip does not function correctly if accessed from within a virtual
environment.
We don't support Debian 10 as a build platform any longer, though we do
still utilize it for our build-tricore-softmmu CI test. It's also
possible that this bug might appear on other derivative platforms and
this workaround may prove useful.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-11-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
distlib is usually not installed on Linux distribution, but it is vendored
into pip. Because the virtual environment has pip via ensurepip, we
can piggy-back on pip's vendored version. This could break if they move
our cheese in the future, but the fix would be simply to require distlib.
If it is debundled, as it is on msys, it is simply available directly.
Signed-off-by: John Snow <jsnow@redhat.com>
[Move to toplevel. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When creating a virtual environment that inherits system packages,
script entry points (like "meson", "sphinx-build", etc) are not
re-generated with the correct shebang. When you are *inside* of the
venv, this is not a problem, but if you are *outside* of it, you will
not have a script that engages the virtual environment appropriately.
Add a mechanism that generates new entry points for pre-existing
packages so that we can use these scripts to run "meson",
"sphinx-build", "pip", unambiguously inside the venv.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-9-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is a routine that is designed to print some usable info for human
beings back out to the terminal if/when "mkvenv ensure" fails to locate
or install a package during configure time, such as meson or sphinx.
Since we are requiring that "meson" and "sphinx" are installed to the
same Python environment as QEMU is configured to build with, this can
produce some surprising failures when things are mismatched. This method
is here to try and ease that sting by offering some actionable
diagnosis.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-8-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This command is to be used to add various packages (or ensure they're
already present) into the configure-provided venv in a modular fashion.
Examples:
mkvenv ensure --online --dir "${source_dir}/python/wheels/" "meson>=0.61.5"
mkvenv ensure --online "sphinx>=1.6.0"
mkvenv ensure "qemu.qmp==0.0.2"
It's designed to look for packages in three places, in order:
(1) In system packages, if the version installed is already good
enough. This way your distribution-provided meson, sphinx, etc are
always used as first preference.
(2) In a vendored packages directory. Here I am suggesting
qemu.git/python/wheels/ as that directory. This is intended to serve as
a replacement for vendoring the meson source for QEMU tarballs. It is
also highly likely to be extremely useful for packaging the "qemu.qmp"
package in source distributions for platforms that do not yet package
qemu.qmp separately.
(3) Online, via PyPI, ***only when "--online" is passed***. This is only
ever used as a fallback if the first two sources do not have an
appropriate package that meets the requirement. The ability to build
QEMU and run tests *completely offline* is not impinged.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-7-jsnow@redhat.com>
[Use distlib to lookup distributions. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Python virtual environments do not typically nest; they may inherit from
the top-level system packages or not at all.
For our purposes, it would be convenient to emulate "nested" virtual
environments to allow callers of the configure script to install
specific versions of python utilities in order to test build system
features, utility version compatibility, etc.
While it is possible to install packages into the system environment
(say, by using the --user flag), it's nicer to install test packages
into a totally isolated environment instead.
As detailed in https://www.qemu.org/2023/03/24/python/, Emulate a nested
venv environment by using .pth files installed into the site-packages
folder that points to the parent environment when appropriate.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-6-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Debian debundles ensurepip for python; NetBSD debundles pyexpat but
ensurepip needs pyexpat. Try our best to offer a helpful error message
instead of just failing catastrophically.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-5-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This script will be responsible for building a lightweight Python
virtual environment at configure time. It works with Python 3.6 or
newer.
It has been designed to:
- work *offline*, no PyPI required.
- work *quickly*, The fast path is only ~65ms on my machine.
- work *robustly*, with multiple fallbacks to keep things working.
- work *cooperatively*, using system packages where possible.
(You can use your distro's meson, no problem.)
Due to its unique position in the build chain, it exists outside of the
installable python packages in-tree and *must* be runnable without any
third party dependencies.
Under normal circumstances, the only dependency required to execute this
script is Python 3.6+ itself. The script is *faster* by several seconds
when setuptools and pip are installed in the host environment, which is
probably the case for a typical multi-purpose developer workstation.
In the event that pip/setuptools are missing or not usable, additional
dependencies may be required on some distributions which remove certain
Python stdlib modules to package them separately:
- Debian may require python3-venv to provide "ensurepip"
- NetBSD may require py310-expat to provide "pyexpat" *
(* Or whichever version is current for NetBSD.)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230511035435.734312-4-jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
