Add initial skeleton nqm.irimager C extension module

.github/workflows/test.yml

@@ -22,5 +22,9 @@ jobs:
           # see https://github.com/pre-commit/pre-commit-hooks/issues/265
           SKIP: "no-commit-to-branch"
         run: poetry run pre-commit run --show-diff-on-failure --color=always
+      - name: Check whether nqm.irimager stubs match implementation
+        env:
+          MYPYPATH: src
+        run: poetry run stubtest nqm.irimager
       - name: Test with pytest
         run: poetry run pytest

.gitignore

@@ -135,6 +135,10 @@ ipython_config.py
 #   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
 #poetry.lock
 
+#   The setup.py file is auto-generated by Poetry if you have
+#   `tool.poetry.build.generate-setup-file = true` set in your pyproject.toml file
+setup.py
+
 # pdm
 #   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
 #pdm.lock

.pre-commit-config.yaml

@@ -44,6 +44,7 @@ repos:
             [
               "-rn", # Only display messages
               "-sn", # Don't display the score
+              "--extension-pkg-whitelist=nqm.irimager", # import our custom C extension
             ]
     -   id: mypy
         name: mypy

README.md

@@ -35,6 +35,21 @@ Tests are written using [`pytest`](https://docs.pytest.org/en/7.2.x/), and can b
 poetry run pytest
 ```
 
+#### Mypy stubtest
+
+You can use
+[Mypy's `stubtest` tool](https://mypy.readthedocs.io/en/stable/stubtest.html)
+to automatically check whether the types in a stub file match the
+implementation.
+
+For most Python code, we put the type information directly in the
+implementation, so we only need this for C/C++ Python extensions, like the
+`nqm.irimager` module.
+
+```bash
+MYPYPATH=src poetry run stubtest nqm.irimager
+```
+
 ### Documentation
 
 [Sphinx](https://www.sphinx-doc.org/en/master/index.html) is used to generate

build.py

@@ -0,0 +1,23 @@
+"""Poetry build script that builds the nqm.irimager Python C++ extension
+"""
+
+from setuptools.extension import Extension
+
+nqm_irimager_extension = Extension(
+    "nqm.irimager",
+    sources=["src/nqm/irimager/irimager.cpp"],
+    define_macros=[("PY_SSIZE_T_CLEAN", None)],
+)
+
+
+def build(setup_kwargs):
+    """
+    This is a callback for poetry used to hook in our extensions.
+    """
+
+    setup_kwargs.update(
+        {
+            # declare the extension so that setuptools will compile it
+            "ext_modules": [nqm_irimager_extension],
+        }
+    )

pyproject.toml

@@ -9,6 +9,12 @@ license = "UNLICENSED"
 readme = "README.md"
 packages = [{include = "nqm", from = "src"}]
 
+
+[tool.poetry.build]
+# build a custom C++ extension using build.py
+script = "build.py"
+generate-setup-file = true
+
 [tool.poetry.dependencies]
 python = "^3.8"
 
@@ -21,9 +27,10 @@ pytest = "^7.2.1"
 sphinx = "^5.3.0"
 myst-parser = "^0.18.1"
 isort = "^5.12.0"
+types-setuptools = ">=45.2.0"
 
 [build-system]
-requires = ["poetry-core"]
+requires = ["poetry-core", "setuptools>=45.2.0"]
 build-backend = "poetry.core.masonry.api"
 
 [tool.pylint.main]

src/nqm/_irimager/__init__.py

@@ -0,0 +1 @@
+# This is a dummy package just to make Poetry happy

src/nqm/irimager/__init__.pyi

@@ -0,0 +1,16 @@
+# This file was auto-generated and modified by hand from
+# `poetry run stubgen -m nqm.irimager`
+
+"""Optris PI and XI imager IR camera controller
+
+We use the IRImagerDirect SDK
+(see http://documentation.evocortex.com/libirimager2/html/index.html)
+to control these cameras.
+"""
+
+class IRImager:
+    """IRImager object - interfaces with a camera."""
+
+    def __init__(self, *args, **kwargs) -> None: ...
+    def test(self) -> int:
+        """Return the number 42"""

src/nqm/irimager/irimager.cpp

@@ -0,0 +1,146 @@
+// contains example code adapted from https://opensource.com/article/22/11/extend-c-python
+
+#include <Python.h>
+#include "structmember.h"
+
+#include <iostream>
+
+// A struct contains the definition of a module
+PyModuleDef irimager = {
+    PyModuleDef_HEAD_INIT,
+    "irimager", // Module name
+    R"(Optris PI and XI imager IR camera controller
+
+We use the IRImagerDirect SDK
+(see http://documentation.evocortex.com/libirimager2/html/index.html)
+to control these cameras.)", // docstring
+    -1,      // Optional size of the module state memory
+    nullptr, // Optional module methods
+    nullptr, // Optional slot definitions
+    nullptr, // Optional traversal function
+    nullptr, // Optional clear function
+    nullptr  // Optional module deallocation function
+};
+
+class IRImager {
+    public:
+    int test() {
+        return 42;
+    }
+};
+
+// Python object that stores an IRImager
+typedef struct {
+    PyObject_HEAD
+    IRImager* m_myclass;
+} IRImagerObject;
+
+PyObject* IRImager_test(PyObject *self, PyObject *args){
+    assert(self);
+
+    IRImagerObject* _self = reinterpret_cast<IRImagerObject*>(self);
+    int val = _self->m_myclass->test();
+    return PyLong_FromLong(val);
+}
+
+static PyMethodDef IRImager_methods[] = {
+    {"test", (PyCFunction)IRImager_test, METH_NOARGS, PyDoc_STR("Return the number 42")},
+    {0, nullptr} /* Sentinel */
+};
+
+static PyMemberDef IRImager_members[] = {
+    // currently no members
+    {nullptr, 0, 0, 0, nullptr} /* Sentinel */
+};
+
+PyObject *IRImager_new(PyTypeObject *type, PyObject *args, PyObject *kwds){
+    std::cout << "IRImager_new() called!" << std::endl;
+
+    IRImagerObject *self = (IRImagerObject*) type->tp_alloc(type, 0);
+    if(self != nullptr){ // -> allocation successfull
+        // assign initial values
+        self->m_myclass = nullptr;
+    }
+    return (PyObject*) self;
+}
+
+int IRImager_init(PyObject *self, PyObject *args, PyObject *kwds){
+    IRImagerObject* m = (IRImagerObject*)self;
+    m->m_myclass = (IRImager*)PyObject_Malloc(sizeof(IRImager));
+
+    if(!m->m_myclass){
+        PyErr_SetString(PyExc_RuntimeError, "Memory allocation failed");
+        return -1;
+    }
+
+    try {
+        new (m->m_myclass) IRImager();
+    } catch (const std::exception& ex) {
+        PyObject_Free(m->m_myclass);
+        m->m_myclass = nullptr;
+        PyErr_SetString(PyExc_RuntimeError, ex.what());
+        return -1;
+    } catch(...) {
+        PyObject_Free(m->m_myclass);
+        m->m_myclass = nullptr;
+        PyErr_SetString(PyExc_RuntimeError, "Initialization failed");
+        return -1;
+    }
+
+    return 0;
+}
+
+void IRImager_dealloc(IRImagerObject *self){
+    std::cout << "IRImager_dealloc() called!" << std::endl;
+    PyTypeObject *tp = Py_TYPE(self);
+
+    IRImagerObject* m = reinterpret_cast<IRImagerObject*>(self);
+
+    if(m->m_myclass){
+        m->m_myclass->~IRImager();
+        PyObject_Free(m->m_myclass);
+    }
+
+    tp->tp_free(self);
+    Py_DECREF(tp);
+};
+
+PyDoc_STRVAR(IRImager_doc, R"(IRImager object - interfaces with a camera.)");
+
+static PyType_Slot IRImager_slots[] = {
+    {Py_tp_new,     (void*)IRImager_new},
+    {Py_tp_init,    (void*)IRImager_init},
+    {Py_tp_dealloc, (void*)IRImager_dealloc},
+    {Py_tp_members, IRImager_members},
+    {Py_tp_methods, IRImager_methods},
+    {Py_tp_doc,     (void*)IRImager_doc},
+    {0, nullptr} /* Sentinel */
+};
+
+static PyType_Spec spec_IrImager = {
+    "nqm.irimager.IRImager",                    // name
+    sizeof(IRImagerObject) + sizeof(IRImager),  // basicsize
+    0,                                          // itemsize
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,   // flags
+    IRImager_slots                              // slots
+};
+
+PyMODINIT_FUNC
+PyInit_irimager(void) {
+    PyObject* module = PyModule_Create(&irimager);
+
+    PyObject *irimager_class = PyType_FromSpec(&spec_IrImager);
+    if (irimager_class == NULL){
+        std::cerr << "Failed to make irimager_class!" << std::endl;
+        return nullptr;
+    }
+    Py_INCREF(irimager_class);
+
+    if(PyModule_AddObject(module, "IRImager", irimager_class) < 0){
+        std::cerr << "Failed to add IRImager!" << std::endl;
+        Py_DECREF(irimager_class);
+        Py_DECREF(module);
+        return nullptr;
+    }
+    return module;
+}

src/nqm/irimager/py.typed

@@ -0,0 +1 @@
+# This file is left blank and is needed for PEP 561 (typing info)

tests/test_irimager.py

@@ -0,0 +1,9 @@
+"""Tests for nqm.irimager.IRImager"""
+from nqm.irimager import IRImager
+
+
+def test_irimager_test():
+    """Tests nqm.irimager.IRImager"""
+    irimager = IRImager()
+
+    assert irimager.test() == 42