Invalid .whl name compiling inside a python virtual (venv) environment

[firth650]

Hi
I had previously tried to compile Pangolin inside a system environment, and, as I was not using a venv, (as is now required), I chose to force the pip install using "--break-system-packages". This compiled and installed fine, and I could run the examples. Unfortunately, as may have been expected, I broke my system packages. and thus had to remove the Pangolin elements.

I have now tried to compile Pangolin inside a venv, and the wheel is not being correctly created. (This is the latest Pangolin from github with the Python_EXECUTABLE swapped for Python3_EXECUTABLE changes)

This is on a raspberry pi4 running Bookworm. In order to keep things simple: This a 100% fresh sdcard install with no other software on the card with all OS updates included.

These were my commands:

git clone --recursive https://github.com/stevenlovegrove/Pangolin.git
 cd Pangolin
./scripts/install_prerequisites.sh recommended
cmake -B build
cmake --build build -t pypangolin_pip_install

This runs without any errors until the final python .whl install (The .whl has an empty name) Output is as below

[ 98%] Linking CXX shared module pypangolin-0.9.2.data/purelib/pypangolin.cpython-311-aarch64-linux-gnu.so
lto-wrapper: warning: using serial compilation of 23 LTRANS jobs
lto-wrapper: note: see the ‘-flto’ option documentation for more information

[ 98%] Built target pypangolin
[ 98%] Creating Wheel /home/robot/LearnOpenCV/Pangolin/build/.whl
[ 98%] Built target pypangolin_wheel
[100%] Installing for selected Python '/home/robot/LearnOpenCV/bin/python3'
ERROR: Invalid requirement: '/home/robot/LearnOpenCV/Pangolin/build/.whl'
Hint: It looks like a path. The path does exist. 
gmake[3]: *** [CMakeFiles/pypangolin_pip_install.dir/build.make:71: CMakeFiles/pypangolin_pip_install] Error 1
gmake[2]: *** [CMakeFiles/Makefile2:957: CMakeFiles/pypangolin_pip_install.dir/all] Error 2
gmake[1]: *** [CMakeFiles/Makefile2:964: CMakeFiles/pypangolin_pip_install.dir/rule] Error 2
gmake: *** [Makefile:390: pypangolin_pip_install] Error 2

I am assuming that the switch to a venv has caused this, but I am unsure

[christian-rauch]

Can you provide steps (creating the virtual environment, building, ...) to reproduce this? I have not tested this in a virtual environment before, so this may indeed cause the problem.

[christian-rauch]

I can reproduce this with the following steps:

# create and active a virtual environment
python3 -m venv pangovenv
source pangovenv/bin/activate
# build and install the pypangolin wheel file
git clone https://github.com/stevenlovegrove/Pangolin.git
cd Pangolin
cmake -B build
cmake --build build -t pypangolin_pip_install

This shows me that Python is correctly found inside the virtual environment:

-- Found Python3: [...]/pangovenv/bin/python3.10 (found version "3.10.12") found components: Interpreter Development Development.Module Development.Embed 
-- Selected Python: '[...]/pangovenv/bin/python3.10'. cmake --build . -t pypangolin_pip_install to use pypangolin module.

and that the pypangolin.cpython-*.so is built:

[ 98%] Linking CXX shared module pypangolin-0.9.2.data/purelib/pypangolin.cpython-310-x86_64-linux-gnu.so

but the wheel file indeed has no name (.whl):

[100%] Creating Wheel [...]/Pangolin/build/.whl
[100%] Built target pypangolin_wheel
[100%] Installing for selected Python '[...]/pangovenv/bin/python3.10'
ERROR: Invalid requirement: '[...]/Pangolin/build/.whl'
Hint: It looks like a path. The path does exist.

[christian-rauch]

The snippet that generated the wheel name fails with:

distutils.errors.DistutilsModuleError: invalid command 'bdist_wheel'

After a:

pip install wheel

the wheel file name should be correct.

[firth650]

Yes, the steps that you took were exactly the same as I did, and I also saw python being correctly found etc.

[christian-rauch]

Can you provide more details which OS and Python version you are using? Which versions of setuptools (pip show setuptools) and wheel (pip show wheel) you have installed?

[christian-rauch]

@firth650 Can you try with #960 if this shows better error messages that help you to debug the issue?

[firth650]

I'm using:
Debian GNU/Linux 12 (bookworm)
setuptools Version: 66.1.1

(LearnOpenCV) robot@:$ pip show wheel
WARNING: Package(s) not found: wheel

AHH!! You had already diagnosed this 100% correctly. I apologise, my mistake. I had installed wheel outside of venv.

It now compiles/installs and runs the "PythonExamples" fine

Again apologies.