Missing requirements: psutil

[dnltz]

This PDK now has a dependency to psutil, which is not part of the standard Python library.

Packages shouldn't be installed directly into a system. I would suggest to introduce https://virtualenv.pypa.io/en/latest/ with a requirements file for this. Alternative, drop psutil and find a better alternative, for example ps inside a subprocess call.

ERROR: /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/python/sg13g2_pycell_lib/__init__.py:105: ModuleNotFoundError: No module named 'psutil'
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/python/sg13g2_pycell_lib/__init__.py:105
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/python/sg13g2_pycell_lib/__init__.py:151
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/python/sg13g2_pycell_lib/__init__.py:240
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/tech/pymacros/autorun.lym:8 (class ModuleNotFoundError)
ERROR: AttributeError: 'NoneType' object has no attribute 'layout'
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout//tech/scripts/sealring.py:34
  /home/daniel/work/aesc/i2c-gpio-expander/pdks/IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout//tech/scripts/sealring.py:70

[ThomasZecha]

IMHO there is no reason to not use software besides the 'standard'. psutil is a well developed, cross-platform library which exactly addresses one need of the 'conditional PyCell compilation' feature.
I would not switch to a virtualenv, see also https://www.klayout.de/forum/discussion/2557/klayout-install-on-linux-system-python-vs-venv.
Nevertheless I've reduce the psutil dependency to the use of the feature, see #230

[KrzysztofHerman]

@dnltz @ThomasZecha can we close this issue ?

[ThomasZecha]

From my pov it can be closed.

[dnltz]

I'm not complaining about psutils itself. It's indeed a well-maintained project.

The problem is you should not install a Python package system-wide on your Linux machine. Actually Ubuntu24 kind-of blocks that now...

$ pip3 install psutils
error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.
    
    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.
    
    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.
    
    See /usr/share/doc/python3.12/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

I have multiple Python projects on my machine installed with each different tool requirements. Installing them all system-wide would end in a mess. You also want to make sure everyone is using the same version to lower support.

In my opinion: there should be a requirements.txt file in the project root directory and documentation how to create and use a virtualenv in the documentation.

[ThomasZecha]

Pleae make a proposal for 'there should be a requirements.txt file in the project root directory and documentation how to create and use a virtualenv in the documentation'

[dnltz]

Sure, @ThomasZecha can you explain when psutils is actually required? I figured out I can use the PDK for digital designs without it, after you moved the function. Would help me to write documentation then.

[ThomasZecha]

psutils will be used if one of the PyCells loaded by https://github.com/IHP-GmbH/IHP-Open-PDK/blob/dev/ihp-sg13g2/libs.tech/klayout/python/sg13g2_pycell_lib/__init__.py uses the #ifdef name instruction for conditional compilation, see also https://github.com/IHP-GmbH/IHP-Open-PDK/tree/dev/ihp-sg13g2/libs.tech/klayout/#readme

[dnltz]

@ThomasZecha thanks for clarification!