pybind / scikit_build_example Goto Github PK

I was just playing around with this to learn more about skikit-build (which is pretty nifty!). I had a two small observations/suggestions:

1. What do you think about making the version requirement more relaxed, e.g.:

cmake_minimum_required(VERSION 3.13...3.18)

It's sometimes useful to run CMake directly using the system-provided distribution, and Ubuntu 20.04.1 LTS is still at CMake 3.16.3.

2. Related: the execute_process command in to extract the site packages directory doesn't parse correctly on that version of CMake. Here, it fails with:

CMake Error at CMakeLists.txt:17 (execute_process):                                               
  execute_process given unknown argument "ECHO_OUTPUT_VARIABLE". 

Is the echo step potentially a leftover from debugging on your end? It seems potentially confusing to users. I would suggest removing it, and also using the `pybind`` package for resolving the path rather than skikit-build:

execute_process(
  COMMAND
    "${Python_EXECUTABLE}" -c
    "import pybind11, os; print(os.path.dirname(os.path.dirname(pybind11.__file__)))"
  OUTPUT_VARIABLE _tmp_sitepackages OUTPUT_STRIP_TRAILING_WHITESPACE)

Hello, everyone

First of all, thank you for providing this build example.

To give some context for my question. I aim to create a pybind11 binding for one C++ function to enable its invocation from Python code. But this function dependes on a third-party library called OpenCASCADE.

I'm building on a windows OS. I have cloned this repository and tried to add a simple function into the main.cpp to test the build. I have added the following lines:

main.cpp:

#include <TopoDS_Shape.hxx>
#include <BRepPrimAPI_MakeBox.hxx>

TopoDS_Shape makeBox(float length, float width, float height){
   return BRepPrimAPI_MakeBox(length, width, height).Shape();
}

    m.def("make_box", &makeBox, "A function that returns a TopoDS_Shape");

And I have also added these lines into the CmakeLists.txt to take into account the OpenCASCADE dependecy:

CmakeLists.txt:

set(OpenCASCADE_DIR "C:/Program Files/OCCT/opencascade-install/cmake")

# OpenCascade
find_package(OpenCASCADE)

# Configure C++ compiler's includes dir
include_directories(SYSTEM ${OpenCASCADE_INCLUDE_DIR})

# Add linker options
foreach(LIB ${OpenCASCADE_LIBRARIES})
    # TODO: add only optimized build in production
    #target_link_libraries(_core PUBLIC debug ${OpenCASCADE_LIBRARY_DIR}d/${LIB}.lib)
    target_link_libraries(_core PUBLIC optimized ${OpenCASCADE_LIBRARY_DIR}/${LIB}.lib)

endforeach(LIB)

set_property(TARGET _core PROPERTY VS_DEBUGGER_ENVIRONMENT "PATH=$<$<CONFIG:DEBUG>:${OpenCASCADE_BINARY_DIR}d>$<$<NOT:$<CONFIG:DEBUG>>:${OpenCASCADE_BINARY_DIR}>;%PATH%")

When I run pip install ./scikit_build_example I have a successful installation, but then when I try to import scikit_build_example I get the following error:

module = self._system_import(name, *args, **kwargs)
ImportError: DLL load failed while importing _core: The specified module could not be found.

Searching about this error I've found some people saying that to solve I could use the following code:

import os
os.add_dll_directory()

So I've tried referencing my opencascade installation folder, that on my machine is on the path: "C:/Program Files/OCCT/opencascade-install/win64/vc14/bin"

It worked. I would like to know if is there some way to specify this path in the moment of the build. If it should be specified in the CmakeLists.txt or in other file like pyproject.toml.

Any insights or examples on this matter would be highly appreciated!

Thank you very much for the attention

Hi:
I can't find wheels.yml anywhere, could you help me?

Windows 11, Python 3.6, pip 21.3.1.

Repeat-by:
Follow instructions in README.md.
Git clone works.
Then type pip install ./scikit_build_example

Expected: builds
Actual:

ERROR: Invalid requirement: './scikit_build_example'

Well, it's Windows, does changing the / to a \ help?
Expected: builds
Actual:

ERROR: Invalid requirement: '.\\scikit_build_example'
Hint: It looks like a path. File '.\scikit_build_example' does not exist.
What about changing it from . to .. so that there's something with the right name it can look at?

It also helps scikit-build-core. :) I'd say it's a hacky interm solution for all backends to pick up on setuptools configuraiton, but it's a reasonable solution until we have a better cross compiling standard.

Expected: builds:
Actual:

Processing c:\users\beryl\source\repos\scikit_build_example
  Installing build dependencies ... error
  ERROR: Command errored out with exit status 1:
   command: 'c:\program files\python36\python.exe' 'c:\Program Files\python36\lib\site-packages\pip' install --ignore-installed --no-user --prefix 'C:\Users\beryl\AppData\Local\Temp\pip-build-env-n4hg686l\overlay' --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'scikit-build-core>=0.3.3' pybind11
       cwd: None
  Complete output (2 lines):
  ERROR: Could not find a version that satisfies the requirement scikit-build-core>=0.3.3 (from versions: none)
  ERROR: No matching distribution found for scikit-build-core>=0.3.3
  ----------------------------------------
WARNING: Discarding file:///C:/Users/beryl/source/repos/scikit_build_example. Command errored out with exit status 1: 'c:\program files\python36\python.exe' 'c:\Program Files\python36\lib\site-packages\pip' install --ignore-installed --no-user --prefix 'C:\Users\beryl\AppData\Local\Temp\pip-build-env-n4hg686l\overlay' --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'scikit-build-core>=0.3.3' pybind11 Check the logs for full command output.
ERROR: Command errored out with exit status 1: 'c:\program files\python36\python.exe' 'c:\Program Files\python36\lib\site-packages\pip' install --ignore-installed --no-user --prefix 'C:\Users\beryl\AppData\Local\Temp\pip-build-env-n4hg686l\overlay' --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'scikit-build-core>=0.3.3' pybind11 Check the logs for full command output.

Hi, how would I go about creating a single module package? Say I have one module with a few classes. The automatically generated signatures of the class functions contain then something like
packagename.modulename.classname
However, as this package only contains one module, the packagename and modulename are redundant information. Is there away to create just the module, and not a package? Or to omit these names in the signatures?

The documentation generated using Sphinx does not contain the signature and the docstrings of the functions add and subtract defined in the extension module code in src/main.cpp.

Steps to reproduce the issue:

• Clone this repository
• cd scikit_build_example/
• Install the package: pip install .
• cd docs/
• make html
• html files generated in docs/_build/ does not contain function signatures and docstrings. See screenshot below

The target module from which docstrings and function signature are to be extracted as documentation is incorrectly referenced in docs/python_example.rst as highlighted in the make html outout below.

$ make html
sphinx-build -b html -d _build/doctrees   . _build/html
Running Sphinx v7.3.6

WARNING: Failed to import python_example.
Possible hints:
* ModuleNotFoundError: No module named 'python_example'
* KeyError: 'python_example'
building [mo]: targets for 0 po files that are out of date
writing output...
building [html]: targets for 2 source files that are out of date
updating environment: [new config] 2 added, 0 changed, 0 removed
reading sources... [100%] python_example
WARNING: autodoc: failed to import module 'python_example'; the following exception was raised:
No module named 'python_example'

writing output... [100%] python_example
/~/scikit_build_example/docs/index.rst:6: WARNING: toctree contains reference to document 'python_example' that doesn't have a title: no link will be generated
/~/scikit_build_example/docs/index.rst:6: WARNING: toctree contains reference to document 'python_example' that doesn't have a title: no link will be generated
/~/scikit_build_example/docs/index.rst:6: WARNING: toctree contains reference to document 'python_example' that doesn't have a title: no link will be generated
generating indices... genindex /~/scikit_build_example/docs/index.rst:6: WARNING: toctree contains reference to document 'python_example' that doesn't have a title: no link will be generated
done
writing additional pages... search /~/scikit_build_example/docs/index.rst:6: WARNING: toctree contains reference to document 'python_example' that doesn't have a title: no link will be generated
done
dumping search index in English (code: en)... done
dumping object inventory... done

Fix

scikit_build_example is the correct target module to mention in docs/python_example.rst from which the function signatures and docstrings are to be extracted.

Hi there, I found this repo when I was deciding on how to port some C++ code to python.

I used to go the way via described in the cmake_example, but after watching @henryiii 's talk from SciPy22 I thought about scikit_build_example would be worth a try.

However, I find it quite hard to understand what the (minimum) necessary components are and how this example works, especially since new/unknown/fancy tools like nox and ruff are used.
For example in this file a beginner wonders if the imports from future are necessary. Comments would be helpful there as well as in the CMakeLists.txt where one can not assume that beginners know where SKBUILD_PROJECT_NAME etc. come from.

Please don't get me wrong, I appreciate this project. I just think it needs a bit more documentation to be really usable for a broader audience

Hello,
I'm trying to make my package "pip installable" by using this project as reference but the lines cited here seem to force an installation directory.

I believe the most standard usage of cmake would require something along the lines of:

include(GNUInstallDirs)
install(TARGETS ${mypybindlib}
  EXPORT ${CMAKE_PROJECT_NAME}Targets
  ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
  LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
  RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})

For instance, CMAKE_INSTALL_LIBDIR translates to a relative directory lib on my system.

I've noticed that this is important because it determines the cmake_install_dir (here) and the import path in src/scikit_build_example/__init__.py.

Is there a way to make this work?

Maybe I'm just missing a way to tell scikit-build to pass a variable to cmake, so that I could handle it directly inside the CMakeLists.txt.

edit:
I found a workaround. It's not ideal (because it doesn't load the install directory from the GNUInstallDirs or my CMakeLists.txt) but it works:

from .lib._core import *

Thanks for the great examples and sorry for the naive question, but I am not a python packaging expert, but when I do:

$ pip install -e .
Obtaining file:///home/gailuron/workspace/formations/scikit_build_example
  Installing build dependencies ... done
  Checking if build backend supports build_editable ... done
ERROR: Project file:///home/gailuron/workspace/formations/scikit_build_example has a 'pyproject.toml' and its build backend is missing the 'build_editable' hook. Since it does not have a 'setup.py' nor a 'setup.cfg', it cannot be installed in editable mode. Consider using a build backend that supports PEP 660.

And I don't know where to start to fix this error.

Maybe proposing a setup.py like this one. But the information are quite redundant with the pyproject.toml.

I'm working on a few python packages using this setup, and there is extra code/functionality on the C++ side that I don't expose to python. I'd like to be able to write unit tests, perhaps using GTEST, that I can integrate into this setup. I attempted incorporating the setup in this tutorial, but I'm unclear about a few things. The way that I understand it, a possible solution could be:

1. Have a github action run tests separately, following an explicit build, not with pip, and then manually run the tests. Perhaps something like this.
2. This seems to require fetching pybind11 explicitly within CMakeLists.txt. I'm not sure if this is fine.
3. This also probably requires CMakeLists.txt files that would work both with pip and cmake. (I'm a beginner in cmake, so I'm assuming there's a way to do this.)

Can someone chime in? Am I overcomplicating things?