Enable Scikit-build as the build backend

.github/workflows/ci.yaml

@@ -20,6 +20,7 @@ jobs:
         export PATH="/opt/drake/bin${PATH:+:${PATH}}"
         export PYTHONPATH="/opt/drake/lib/python$(python3 -c 'import sys; print("{0}.{1}".format(*sys.version_info))')/site-packages${PYTHONPATH:+:${PYTHONPATH}}"
         export LD_LIBRARY_PATH="/opt/drake/lib${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}"
-        pip3 install pybind11[global] pytest
+        pip3 uninstall numpy
+        pip3 install pybind11[global] pytest numpy drake
         pip3 install --verbose .[test]
-        py.test
+        python3 -m pytest

CMakeLists.txt

@@ -6,12 +6,14 @@ cmake_minimum_required(VERSION 3.16...3.27)
 
 # Scikit-build-core sets these values for you, or you can just hard-code the
 # name and version.
-project(drake_extension LANGUAGES CXX)
+project(
+  ${SKBUILD_PROJECT_NAME}
+  VERSION ${SKBUILD_PROJECT_VERSION}
+  LANGUAGES CXX)
 
 include(CTest)
 option(RUN_X11_TESTS "Run tests that require X11" OFF)
 find_package(drake CONFIG REQUIRED)
-find_package(pybind11 CONFIG REQUIRED)
 
 execute_process(COMMAND ${Python3_EXECUTABLE}-config --exec-prefix
   OUTPUT_VARIABLE PYTHON_EXEC_PREFIX
@@ -24,6 +26,11 @@ get_filename_component(PYTHONPATH
   REALPATH
 )
 
+# Find the module development requirements (requires FindPython from 3.17 or
+# scikit-build-core's built-in backport)
+#find_package(Python3 REQUIRED COMPONENTS Interpreter Development.Module)
+find_package(pybind11 CONFIG REQUIRED)
+
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
@@ -32,6 +39,14 @@ set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 # Add a library using FindPython's tooling (pybind11 also provides a helper like
 # this)
-pybind11_add_module(drake_extension MODULE src/drake_extension.cpp)
-target_link_libraries(drake_extension PUBLIC drake::drake)
-set_target_properties(drake_extension PROPERTIES CXX_VISIBILITY_PRESET default)
+#python3_add_library(_ext MODULE src/ext.cpp WITH_SOABI)
+#target_link_libraries(_ext PUBLIC drake::drake pybind11::headers)
+pybind11_add_module(_ext MODULE src/ext.cpp)
+target_link_libraries(_ext PUBLIC drake::drake)
+set_target_properties(_ext PROPERTIES CXX_VISIBILITY_PRESET default)
+
+# This is passing in the version as a define just as an example
+target_compile_definitions(_ext PRIVATE VERSION_INFO=${PROJECT_VERSION})
+
+# The install directory is the output (wheel) directory
+install(TARGETS _ext DESTINATION drake_extension)

README.md

@@ -16,7 +16,7 @@ If you think the current setup can be improved, please open an issue or a pull r
 
 ## Setup Guide
 > [!NOTE]
-> The setup has only been tested with Ubuntu 24.04 (Noble) operating system, Python 3.12 and Drake v1.32.0
+> The setup has only been tested with Ubuntu 22.04 (Jammy) operating system, Python 3.10 and Drake v1.32.0
 > If you encountered any issues feel free to leave an issue so we can fix it together.
 > You are also welcome to make a PR and extend the support.
 
@@ -47,7 +47,6 @@ py.test
 ```
 
 ## TODOs
-- [ ] Add Github Actions to Automated Testing
 - [ ] Add a Dockerfile for more reproducibility and transparency of the setup
 - [ ] Try `nanobind` and compare resulting binary sizes with `pybind`
 - [ ] Add information about how to shared the packaged python wheel.

pyproject.toml

@@ -1,11 +1,7 @@
 [build-system]
-requires = [
-    "setuptools>=42",
-    "wheel",
-    "ninja",
-    "cmake>=3.12",
-]
-build-backend = "setuptools.build_meta"
+requires = ["scikit-build-core>=0.3.3", "pybind11"]
+build-backend = "scikit_build_core.build"
+
 
 [project]
 name = "drake_extension"
@@ -40,6 +36,9 @@ filterwarnings = [
 ]
 testpaths = ["tests"]
 
+[tool.scikit-build]
+cmake.verbose = true
+logging.level = "INFO"
 
 [tool.cibuildwheel]
 build-frontend = "build[uv]"

src/drake_extension/__init__.py

@@ -0,0 +1,4 @@
+from __future__ import annotations
+from ._ext import __doc__, __version__, SimpleAdder
+
+__all__ = ["__doc__", "__version__", "SimpleAdder"]

src/drake_extension.cpp → src/ext.cpp

@@ -6,6 +6,9 @@
 #include <pybind11/pybind11.h>
 #include <drake/systems/framework/leaf_system.h>
 
+#define STRINGIFY(x) #x
+#define MACRO_STRINGIFY(x) STRINGIFY(x)
+
 namespace py = pybind11;
 
 using drake::systems::BasicVector;
@@ -37,7 +40,7 @@ class SimpleAdder : public LeafSystem<T> {
 };
 
 
-PYBIND11_MODULE(drake_extension , m) {
+PYBIND11_MODULE(_ext , m) {
   m.doc() = "Example module interfacing with pydrake and Drake C++";
 
   py::module::import("pydrake.systems.framework");
@@ -46,6 +49,12 @@ PYBIND11_MODULE(drake_extension , m) {
 
   py::class_<SimpleAdder<T>, LeafSystem<T>>(m, "SimpleAdder")
       .def(py::init<T>(), py::arg("add"));
+
+  #ifdef VERSION_INFO
+    m.attr("__version__") = MACRO_STRINGIFY(VERSION_INFO);
+  #else
+    m.attr("__version__") = "dev";
+  #endif
 }
 
 }  // namespace drake_extension

tests/test_simple_adder.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import numpy as np
 from drake_extension import SimpleAdder