Github-CI:

This is an example of how to create a Modern CMake C++/Python Project.

This project aim to explain how you build a Python 3.6+ native wheel package using Python3 and a setup.py.
e.g. You have a cross platform C++ library (using a CMake based build) and a Python wrapper on it thanks to SWIG.
Then you want to provide a cross-platform Python packages to consume it in a Python project...

This project should run on GNU/Linux, MacOS and Windows.

You'll need:

• "CMake >= 3.18".
• "Python >= 3.6" and python module 'pip' (ed "setuptools" and "wheel" will be auto installed on demand).

The project layout is as follow:

• CMakeLists.txt Top-level for CMake based build.

• cmake Subsidiary CMake files.

  • python.cmake All internall Python CMake stuff.

• ci Root directory for continuous integration.

• Foo Root directory for Foo library.

  • CMakeLists.txt for Foo.
  • include public folder.
    • foo
      • Foo.hpp
  • src private folder.
    • src/Foo.cpp
  • python
    • CMakeLists.txt for Foo Python.
    • foo.i SWIG Python wrapper.

• Bar Root directory for Bar library.

  • CMakeLists.txt for Bar.
  • include public folder.
    • bar
      • Bar.hpp
  • src private folder.
    • src/Bar.cpp
  • python
    • CMakeLists.txt for Bar Python.
    • bar.i SWIG Python wrapper.

• FooBar Root directory for FooBar library.

  • CMakeLists.txt for FooBar.
  • include public folder.
    • foobar
      • FooBar.hpp
  • src private folder.
    • src/FooBar.cpp
  • python
    • CMakeLists.txt for FooBar Python.
    • foobar.i SWIG Python wrapper.

• python Root directory for Python template files

  • setup.py.in setup.py template for the Python native package.

To complexify a little, the CMake project is composed of three libraries (Foo, Bar and FooBar) with the following dependencies:

Foo:
Bar:
FooBar: PUBLIC Foo PRIVATE Bar

To Create a native dependent package which will contains two parts:

• A bunch of native libraries for the supported platform targeted.
• The Python code depending on it.

note: Since Pypi.org support multiple packages, we will simply upload one package per supported platform.

The pipeline for linux-x86-64 should be as follow:

Thus we have the C++ shared library libFoo.so and the SWIG generated Python wrappers e.g. pyfoo.py in the same package.

Here some dev-note concerning this setup.py.

• This package is a native package containing native libraries.

Then you can generate the package and install it locally using:

python3 setup.py bdist_wheel
python3 -m pip install --user --find-links=dist pythonnative

If everything good the package (located in <buildir>/python/dist) should have this layout:

{...}/dist/pythonnative-X.Y.9999-cp3Z-cp3Z-<platform>.whl:
\- pythonnative
   \- __init__.py
   \- .libs
      \- libFoo.so
      \- ...
   \- foo
      \- __init__.py
      \- pyFoo.py
      \- _pyFoo.so
...

note: <platform> could be manylinux2014_x86_64, macosx_10_9_x86_64 or win-amd64.

tips: since wheel package are just zip archive you can use unzip -l <package>.whl to study their layout.

Few links on the subject...

Project layout:

• The Pitchfork Layout Revision 1 (cxx-pflR1)

CMake:

• https://llvm.org/docs/CMakePrimer.html
• https://cliutils.gitlab.io/modern-cmake/
• https://cgold.readthedocs.io/en/latest/

Python:

• Packaging Python Project
• PEP 600 Future 'manylinux' Platform Tags

Image has been generated using plantuml:

plantuml -Tsvg docs/{file}.dot

So you can find the dot source files in docs.

Apache 2. See the LICENSE file for details.

This is not an official Google product, it is just code that happens to be owned by Google.