simplify setup.py and single source version number in it

.gitlab-ci.yml

@@ -7,11 +7,9 @@ test-evalhyd-python:
   script:
     # print Python version
     - python --version
-    # install dependencies
-    - python -m pip install numpy pybind11
     # compile and install package
-    - python -m pip install .
-    # make sure package can be imported
-    - python -c "import evalhyd"
+    - python -m pip --user install .
+    # make sure package can be imported and check version
+    - python -c "import evalhyd;print(evalhyd.__version__)"
     # run test suite
     - (cd ./tests && python run_all_tests.py)

pyproject.toml

+[build-system]
+requires = [
+    "setuptools>=42",
+    "wheel",
+    "pybind11>=2.8.0",
+    "numpy>1.16",
+]
+
+build-backend = "setuptools.build_meta"

requirements.txt

-pybind11>=2.0.1
-numpy>=1.16

setup.py

-from setuptools import setup, Extension
-from setuptools.command.build_ext import build_ext
 import sys
 import os
-import setuptools
 
-__version__ = '0.0.1'
-
-
-def read_requirements(filename):
-    requires = []
-    with open(filename, 'r') as fr:
-        for line in fr:
-            package = line.strip()
-            if package:
-                requires.append(package)
-
-    return requires
-
-
-class get_pybind_include(object):
-    """Helper class to determine the pybind11 include path
-
-    The purpose of this class is to postpone importing pybind11
-    until it is actually installed, so that the ``get_include()``
-    method can be invoked. """
-
-    def __init__(self, user=False):
-        self.user = user
-
-    def __str__(self):
-        import pybind11
-        return pybind11.get_include(self.user)
-
-
-class get_numpy_include(object):
-    """Helper class to determine the numpy include path
+from pybind11 import get_cmake_dir
+from pybind11.setup_helpers import Pybind11Extension, build_ext
+from setuptools import setup
+import numpy
 
-    The purpose of this class is to postpone importing numpy
-    until it is actually installed, so that the ``get_include()``
-    method can be invoked. """
 
-    def __init__(self):
-        pass
-
-    def __str__(self):
-        import numpy as np
-        return np.get_include()
+__version__ = '0.0.1'
 
 
 ext_modules = [
-    Extension(
-        'evalhyd',
+    Pybind11Extension(
+        "evalhyd",
         ['src/evalhyd-python.cpp',
          'deps/evalhyd/src/probabilist/evaluator_brier.cpp',
          'deps/evalhyd/src/probabilist/evaluator_elements.cpp',
          'deps/evalhyd/src/probabilist/evaluator_quantiles.cpp'],
         include_dirs=[
-            # Path to pybind11 headers
-            get_pybind_include(),
-            get_pybind_include(user=True),
-            get_numpy_include(),
-            os.path.join(os.getcwd(), 'deps', 'evalhyd', 'deps', 'xtl', 'include'),
-            os.path.join(os.getcwd(), 'deps', 'evalhyd', 'deps', 'xtensor', 'include'),
+            numpy.get_include(),
+            os.path.join(os.getcwd(), 'deps', 'evalhyd', 'deps', 'xtl',
+                         'include'),
+            os.path.join(os.getcwd(), 'deps', 'evalhyd', 'deps', 'xtensor',
+                         'include'),
             os.path.join(os.getcwd(), 'deps', 'xtensor-python', 'include'),
             os.path.join(os.getcwd(), 'deps', 'evalhyd', 'include'),
             os.path.join(os.getcwd(), 'deps', 'evalhyd', 'src'),
             os.path.join(sys.prefix, 'include'),
             os.path.join(sys.prefix, 'Library', 'include')
         ],
-        language='c++'
+        language='c++',
+        define_macros=[('VERSION_INFO', __version__)],
     ),
 ]
 
-
-def has_flag(compiler, flagname):
-    """Return a boolean indicating whether a flag name is supported on
-    the specified compiler.
-    """
-    import tempfile
-    with tempfile.NamedTemporaryFile('w', suffix='.cpp') as f:
-        f.write('int main (int argc, char **argv) { return 0; }')
-        try:
-            compiler.compile([f.name], extra_postargs=[flagname])
-        except setuptools.distutils.errors.CompileError:
-            return False
-    return True
-
-
-def cpp_flag(compiler):
-    """Return the -std=c++14 compiler flag  and errors when the flag is
-    no available.
-    """
-    if has_flag(compiler, '-std=c++14'):
-        return '-std=c++14'
-    else:
-        raise RuntimeError('C++14 support is required by xtensor!')
-
-
-class BuildExt(build_ext):
-    """A custom build extension for adding compiler-specific options."""
-    c_opts = {
-        'msvc': ['/EHsc'],
-        'unix': [],
-    }
-
-    if sys.platform == 'darwin':
-        c_opts['unix'] += ['-stdlib=libc++', '-mmacosx-version-min=10.7']
-
-    def build_extensions(self):
-        ct = self.compiler.compiler_type
-        opts = self.c_opts.get(ct, [])
-        if ct == 'unix':
-            opts.append('-DVERSION_INFO="%s"' % self.distribution.get_version())
-            opts.append(cpp_flag(self.compiler))
-            if has_flag(self.compiler, '-fvisibility=hidden'):
-                opts.append('-fvisibility=hidden')
-        elif ct == 'msvc':
-            opts.append('/DVERSION_INFO=\\"%s\\"' % self.distribution.get_version())
-        for ext in self.extensions:
-            ext.extra_compile_args = opts
-        build_ext.build_extensions(self)
-
-
 setup(
     name='evalhyd-python',
     version=__version__,
@@ -131,7 +43,6 @@ setup(
     description='Python bindings for EvalHyd',
     long_description='An evaluator for streamflow predictions.',
     ext_modules=ext_modules,
-    install_requires=read_requirements('requirements.txt'),
-    cmdclass={'build_ext': BuildExt},
+    cmdclass={'build_ext': build_ext},
     zip_safe=False,
 )

src/evalhyd-python.cpp

 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>
 
+#define STRINGIFY(x) #x
+#define MACRO_STRINGIFY(x) STRINGIFY(x)
+
 #define FORCE_IMPORT_ARRAY
 #include <xtensor-python/pytensor.hpp>
 
@@ -203,4 +206,10 @@ PYBIND11_MODULE(evalhyd, m)
         py::arg("q_obs"), py::arg("q_prd"), py::arg("metrics"),
         py::arg("q_thr") = empty_1d, py::arg("t_msk") = empty_2d
     );
+
+#ifdef VERSION_INFO
+    m.attr("__version__") = MACRO_STRINGIFY(VERSION_INFO);
+#else
+    m.attr("__version__") = "dev";
+#endif
 }