23.09.2021 21:44, John Snow wrote:
On Thu, Sep 23, 2021 at 2:32 PM Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com
<mailto:vsement...@virtuozzo.com>> wrote:
23.09.2021 21:07, John Snow wrote:
> Add a warning for when 'iotests' runs against a qemu namespace that
> isn't the one in the source tree. This might occur if you have
> (accidentally) installed the Python namespace package to your local
> packages.
>
> (I'm not going to say that this is because I bit myself with this,
> but you can fill in the blanks.)
>
> In the future, we will pivot to always preferring a specific installed
> instance of qemu python packages managed directly by iotests. For now
> simply warn if there is an ambiguity over which instance that iotests
> might use.
>
> Example: If a user has navigated to ~/src/qemu/python and executed
> `pip install .`, you will see output like this when running `./check`:
>
> WARNING: 'qemu' python packages will be imported from outside the source
tree ('/home/jsnow/src/qemu/python')
> Importing instead from
'/home/jsnow/.local/lib/python3.9/site-packages/qemu'
>
> Signed-off-by: John Snow <js...@redhat.com <mailto:js...@redhat.com>>
> ---
> tests/qemu-iotests/testenv.py | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
>
> diff --git a/tests/qemu-iotests/testenv.py
b/tests/qemu-iotests/testenv.py
> index 99a57a69f3a..1c0f6358538 100644
> --- a/tests/qemu-iotests/testenv.py
> +++ b/tests/qemu-iotests/testenv.py
> @@ -16,6 +16,8 @@
> # along with this program. If not, see <http://www.gnu.org/licenses/
<http://www.gnu.org/licenses/>>.
> #
>
> +import importlib.util
> +import logging
> import os
> import sys
> import tempfile
> @@ -112,6 +114,27 @@ def init_directories(self) -> None:
> # Path where qemu goodies live in this source tree.
> qemu_srctree_path = Path(__file__, '../../../python').resolve()
>
> + # Warn if we happen to be able to find qemu namespace packages
> + # (using qemu.qmp as a bellwether) from an unexpected location.
> + # i.e. the package is already installed in the user's
environment.
> + try:
> + qemu_spec = importlib.util.find_spec('qemu.qmp')
> + except ModuleNotFoundError:
> + qemu_spec = None
> +
> + if qemu_spec and qemu_spec.origin:
> + spec_path = Path(qemu_spec.origin)
> + try:
> + _ = spec_path.relative_to(qemu_srctree_path)
It took some time and looking at specification trying to understand what's
going on here :)
Could we just use:
if not Path(qemu_spec.origin).is_relative_to(qemu_srctree_path):
... logging ...
Nope, that's 3.9+ only. (I made the same mistake.)
Oh :(
OK
> + except ValueError:
> + self._logger.warning(
> + "WARNING: 'qemu' python packages will be imported
from"
> + " outside the source tree ('%s')",
> + qemu_srctree_path)
why not use f-strings ? :)
> + self._logger.warning(
> + " Importing instead from '%s'",
> + spec_path.parents[1])
> +
Also, I'd move this new chunk of code to a separate function (may be even
out of class, as the only usage of self is self._logger, which you introduce
with this patch. Still a method would be OK too). And then, just call it from
__init__(). Just to keep init_directories() simpler. And with this new code we
don't init any directories to pass to further test execution, it's just a check
for runtime environment.
I wanted to keep the wiggly python import logic all in one place so that it was
harder to accidentally forget a piece of it if/when we adjust it.
Hmm right.. I didn't look from that point of view.
So, we actually check the library we are using now is the same which we pass to
called tests.
So, it's a right place for it. And it's about the fact that we are still
hacking around importing libraries :) Hope for bright future.
I can create a standalone function for it, but I'd need to stash that
qemu_srctree_path variable somewhere if we want to call that runtime check from
somewhere else, because I don't want to compute it twice. Is it still worth
doing in your opinion if I just create a method/function and pass it the
qemu_srctree_path variable straight from init_directories()?
My first impression was that init_directories() is not a right place. But now I
see that we want to check exactly this qemu_srctree_path, which we are going to
pass to tests.
So, I'm OK as is.
Still, may be adding helper function like
def warn_if_module_loads_not_from(module_name, path):
worth doing.. I'm not sure, up to you.
Another question comes to my mind:
You say "'qemu' python packages will be imported from". But are you sure? We
pass correct PYTHONPATH, where qemu_srctree_path goes first, doesn't it guarantee that
qemu package will be loaded from it?
I now read in spec about PYTHONPATH:
The default search path is installation dependent, but generally begins with
prefix/lib/pythonversion (see PYTHONHOME above). It is always appended to
PYTHONPATH.
So, if do warn something, it seems correct to say that "System version of qemu is
{spec_path.parents[1]}, but sorry, we prefer our own (and better) version at
{qemu_srctree_path}".
Or what I miss? In commit message it's not clean did you really see such
problem or not :)
Not adding _logger is valid, though. I almost removed it myself. I'll squash
that in.
> self.pythonpath = os.pathsep.join(filter(None, (
> self.source_iotests,
> str(qemu_srctree_path),
> @@ -230,6 +253,7 @@ def __init__(self, imgfmt: str, imgproto: str,
aiomode: str,
>
> self.build_root = os.path.join(self.build_iotests, '..', '..')
>
> + self._logger = logging.getLogger('qemu.iotests')
> self.init_directories()
> self.init_binaries()
>
>
--
Best regards,
Vladimir
--
Best regards,
Vladimir