On 6/5/20 12:21 PM, Vladimir Sementsov-Ogievskiy wrote:
> 03.06.2020 03:15, John Snow wrote:
>> pipenv is a tool used for managing virtual environments with precisely
>> specified dependencies. It is separate from the dependencies listed in
>> setup.py, which are (by 'best practices') not supposed to be pinned.
>>
>> Note that pipenv is not required to install or use this module; this is
>> just a convenience for in-tree developing.
>>
>> 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 loudout 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 <js...@redhat.com>
>> ---
>> python/Pipfile | 11 +++++++++++
>> 1 file changed, 11 insertions(+)
>> create mode 100644 python/Pipfile
>>
>> diff --git a/python/Pipfile b/python/Pipfile
>> new file mode 100644
>> index 00000000000..9534830b5eb
>> --- /dev/null
>> +++ b/python/Pipfile
>> @@ -0,0 +1,11 @@
>> +[[source]]
>> +name = "pypi"
>> +url = "https://pypi.org/simple";
>> +verify_ssl = true
>> +
>> +[dev-packages]
>> +
>> +[packages]
>> +
>> +[requires]
>> +python_version = "3.6"
>>
>
> Should it be >= or something like this?
>
I think logistically that makes sense, but I'm not sure if the tool
supports it.
I decided to target the oldest version of Python we support (for
non-build infrastructure) to ensure a minimum viability.
> And, how should I use this all?
>
> My failed attempt:
> [root@kvm python]# pipenv install --python /usr/bin/python3
> Virtualenv already exists!
> Removing existing virtualenv…
> Creating a virtualenv for this project…
> Pipfile: /work/src/qemu/john-python-installable/python/Pipfile
> Using /usr/bin/python3 (3.7.5) to create virtualenv…
> ⠹ Creating virtual environment...created virtual environment
> CPython3.7.5.final.0-64 in 112ms
> creator
> CPython3Posix(dest=/root/.local/share/virtualenvs/python-4FwBBPCc,
> clear=False, global=False)
> seeder FromAppData(download=False, pip=latest, setuptools=latest,
> wheel=latest, via=copy,
> app_data_dir=/root/.local/share/virtualenv/seed-app-data/v1.0.1)
> activators
> BashActivator,CShellActivator,FishActivator,PowerShellActivator,PythonActivator,XonshActivator
>
>
> ✔ Successfully created virtual environment!
> Virtualenv location: /root/.local/share/virtualenvs/python-4FwBBPCc
> Warning: Your Pipfile requires python_version 3.6, but you are using
> 3.7.5 (/root/.local/share/v/p/bin/python).
> $ pipenv --rm and rebuilding the virtual environment may resolve the
> issue.
> $ pipenv check will surely fail.
> Installing dependencies from Pipfile.lock (44d7bd)…
> 🐍 ▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉ 0/0 — 00:00:00
> To activate this project's virtualenv, run pipenv shell.
> Alternatively, run a command inside the virtualenv with pipenv run.
> [root@kvm python]# pipenv shell
> Warning: Your Pipfile requires python_version 3.6, but you are using
> 3.7.5 (/root/.local/share/v/p/bin/python).
> $ pipenv --rm and rebuilding the virtual environment may resolve the
> issue.
> $ pipenv check will surely fail.
> Launching subshell in virtual environment…
> . /root/.local/share/virtualenvs/python-4FwBBPCc/bin/activate
> [root@kvm work]# .
> /root/.local/share/virtualenvs/python-4FwBBPCc/bin/activate
> (python) [root@kvm work]# python
> Python 3.7.5 (default, Oct 17 2019, 12:09:47)
> [GCC 9.2.1 20190827 (Red Hat 9.2.1-1)] on linux
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import pylint
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> ModuleNotFoundError: No module named 'pylint'
>>>>
>
> and iotest 297 says: "pylint-3 not found"
>
Ah! that's a bug in iotest 297. It's expecting the fedora package there.
I'll have to fix that.
> (honestly, I'm new to using python virtual environment)
>
Good questions. I'll document this in the README.rst for this folder,
actually...
1. Create a virtual environment
> pipenv sync --dev
jsnow@probe ~/s/q/python (python-package-refactor)> pipenv sync --dev
Creating a virtualenv for this project…
Pipfile: /home/jsnow/src/qemu/python/Pipfile
Using /usr/bin/python3.6 (3.6.10) to create virtualenv…
⠏ Creating virtual environment...Using base prefix '/usr'
New python executable in
/home/jsnow/.local/share/virtualenvs/python-QepCANQl/bin/python3.6
Also creating executable in
/home/jsnow/.local/share/virtualenvs/python-QepCANQl/bin/python
Installing setuptools, pip, wheel...done.
Running virtualenv with interpreter /usr/bin/python3.6
✔ Successfully created virtual environment!
Virtualenv location: /home/jsnow/.local/share/virtualenvs/python-QepCANQl
Installing dependencies from Pipfile.lock (44d7bd)…
🐍 ▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉▉ 17/17 — 00:00:07
To activate this project's virtualenv, run pipenv shell.
Alternatively, run a command inside the virtualenv with pipenv run.
All dependencies are now up-to-date!
This command can both create and synchronize the venv's packages with
those listed in Pipfile.lock.
It may be helpful to know that Pipfile describes which packages, with
coarse version requirements. Pipfile.lock describes EXACTLY which
package versions to install.
Pipenv, therefore, is a way to produce consistent execution environments
in which we can run tests that are the same for everybody.
When we want to update our packages for this repeatable environment, we
can use 'pipenv update' and commit the Pipfile.lock changes back to git.
(Note, using --dev here installs the development dependencies. If you
omit it, you won't get any packages installed, because there are no
runtime dependencies for this package!)
2. Where did it create the venv?
jsnow@probe ~/s/q/python (python-package-refactor)> pipenv --venv
/home/jsnow/.local/share/virtualenvs/python-QepCANQl
3. Entering the venv
jsnow@probe ~/s/q/python (python-package-refactor)> pipenv shell
Launching subshell in virtual environment…
Welcome to fish, the friendly interactive shell
jsnow@probe ~/s/q/python (python-package-refactor)> source
/home/jsnow/.local/share/virtualenvs/python-QepCANQl/bin/activate.fish
(python) jsnow@probe ~/s/q/python (python-package-refactor)>
^^^^^^ the virtual environment I am in
my git branch ^^^^^^^^^^^^^^^^^^^^^^^
This just automates opening a sub-shell and then sourcing the activation
file for you. You can do it manually if you'd like.
4. Installing the QEMU package in development mode to the venv
So far, pipenv only installed our development requirements. Install the
package itself.
>From inside `pipenv shell`:
> pip install -e .
Obtaining file:///home/jsnow/src/qemu/python
Installing collected packages: qemu
Running setup.py develop for qemu
Successfully installed qemu
Or, if you are outside the venv:
> pipenv run pip install -e .
5. Using the qemu package
(From inside the venv)
(python) jsnow@probe ~/s/q/python (python-package-refactor)> python3
Python 3.6.10 (default, Dec 27 2019, 13:40:13)
[GCC 9.2.1 20190827 (Red Hat 9.2.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import qemu.core
>>> dir(qemu.core)
['QEMUMachine', 'QEMUMonitorProtocol', 'QEMUQtestMachine',
'QEMUQtestProtocol', '__all__', '__builtins__', '__cached__', '__doc__',
'__file__', '__loader__', '__name__', '__package__', '__path__',
'__spec__', 'accel', 'kvm_available', 'list_accel', 'machine', 'qmp',
'qtest', 'tcg_available']
>>>
