setup.py

import os
import platform
import re
import sys
from distutils.command.build_ext import build_ext
from distutils.errors import CCompilerError
from distutils.errors import DistutilsExecError
from distutils.errors import DistutilsPlatformError
from setuptools import Distribution as _Distribution, Extension
from setuptools import setup
from setuptools import find_packages
from setuptools.command.test import test as TestCommand

cmdclass = {}
if sys.version_info < (2, 7):
    raise Exception("SQLAlchemy requires Python 2.7 or higher.")

cpython = platform.python_implementation() == 'CPython'

ext_modules = [
    Extension('sqlalchemy.cprocessors',
              sources=['lib/sqlalchemy/cextension/processors.c']),
    Extension('sqlalchemy.cresultproxy',
              sources=['lib/sqlalchemy/cextension/resultproxy.c']),
    Extension('sqlalchemy.cutils',
              sources=['lib/sqlalchemy/cextension/utils.c'])
]

ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError)
if sys.platform == 'win32':
    # 2.6's distutils.msvc9compiler can raise an IOError when failing to
    # find the compiler
    ext_errors += (IOError,)


class BuildFailed(Exception):

    def __init__(self):
        self.cause = sys.exc_info()[1]  # work around py 2/3 different syntax


class ve_build_ext(build_ext):
    # This class allows C extension building to fail.

    def run(self):
        try:
            build_ext.run(self)
        except DistutilsPlatformError:
            raise BuildFailed()

    def build_extension(self, ext):
        try:
            build_ext.build_extension(self, ext)
        except ext_errors:
            raise BuildFailed()
        except ValueError:
            # this can happen on Windows 64 bit, see Python issue 7511
            if "'path'" in str(sys.exc_info()[1]):  # works with both py 2/3
                raise BuildFailed()
            raise

cmdclass['build_ext'] = ve_build_ext


class Distribution(_Distribution):

    def has_ext_modules(self):
        # We want to always claim that we have ext_modules. This will be fine
        # if we don't actually have them (such as on PyPy) because nothing
        # will get built, however we don't want to provide an overally broad
        # Wheel package when building a wheel without C support. This will
        # ensure that Wheel knows to treat us as if the build output is
        # platform specific.
        return True


class PyTest(TestCommand):
    # from http://pytest.org/latest/goodpractices.html\
    # #integrating-with-setuptools-python-setup-py-test-pytest-runner
    # TODO: prefer pytest-runner package at some point, however it was
    # not working at the time of this comment.
    user_options = [('pytest-args=', 'a', "Arguments to pass to py.test")]

    default_options = ["-n", "4", "-q", "--nomemory"]

    def initialize_options(self):
        TestCommand.initialize_options(self)
        self.pytest_args = ""

    def finalize_options(self):
        TestCommand.finalize_options(self)
        self.test_args = []
        self.test_suite = True

    def run_tests(self):
        import shlex
        # import here, cause outside the eggs aren't loaded
        import pytest
        errno = pytest.main(self.default_options + shlex.split(self.pytest_args))
        sys.exit(errno)

cmdclass['test'] = PyTest


def status_msgs(*msgs):
    print('*' * 75)
    for msg in msgs:
        print(msg)
    print('*' * 75)


with open(
        os.path.join(
            os.path.dirname(__file__),
            'lib', 'sqlalchemy', '__init__.py')) as v_file:
    VERSION = re.compile(
        r".*__version__ = '(.*?)'",
        re.S).match(v_file.read()).group(1)

with open(os.path.join(os.path.dirname(__file__), 'README.rst')) as r_file:
    readme = r_file.read()


def run_setup(with_cext):
    kwargs = {}
    if with_cext:
        kwargs['ext_modules'] = ext_modules
    else:
        kwargs['ext_modules'] = []

    setup(
        name="SQLAlchemy",
        version=VERSION,
        description="Database Abstraction Library",
        author="Mike Bayer",
        author_email="mike_mp@zzzcomputing.com",
        url="http://www.sqlalchemy.org",
        packages=find_packages('lib'),
        package_dir={'': 'lib'},
        license="MIT License",
        cmdclass=cmdclass,
        tests_require=['pytest>=2.5.2,!=3.9.1,!=3.9.2', 'mock', 'pytest-xdist'],
        long_description=readme,
        python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*",
        classifiers=[
            "Development Status :: 5 - Production/Stable",
            "Intended Audience :: Developers",
            "License :: OSI Approved :: MIT License",
            "Programming Language :: Python",
            "Programming Language :: Python :: 2",
            "Programming Language :: Python :: 2.7",
            "Programming Language :: Python :: 3",
            "Programming Language :: Python :: 3.4",
            "Programming Language :: Python :: 3.5",
            "Programming Language :: Python :: 3.6",
            "Programming Language :: Python :: 3.7",
            "Programming Language :: Python :: Implementation :: CPython",
            "Programming Language :: Python :: Implementation :: PyPy",
            "Topic :: Database :: Front-Ends",
            "Operating System :: OS Independent",
        ],
        distclass=Distribution,
        extras_require={
            'mysql': ['mysqlclient'],
            'pymysql': ['pymysql'],
            'postgresql': ['psycopg2'],
            'postgresql_psycopg2binary': ['psycopg2-binary'],
            'postgresql_pg8000': ['pg8000'],
            'postgresql_psycopg2cffi': ['psycopg2cffi'],
            'oracle': ['cx_oracle'],
            'mssql_pyodbc': ['pyodbc'],
            'mssql_pymssql': ['pymssql'],
            'mssql': ['pyodbc'],
        },
        **kwargs
    )

if not cpython:
    run_setup(False)
    status_msgs(
        "WARNING: C extensions are not supported on " +
        "this Python platform, speedups are not enabled.",
        "Plain-Python build succeeded."
    )
elif os.environ.get('DISABLE_SQLALCHEMY_CEXT'):
    run_setup(False)
    status_msgs(
        "DISABLE_SQLALCHEMY_CEXT is set; " +
        "not attempting to build C extensions.",
        "Plain-Python build succeeded."
    )

else:
    try:
        run_setup(True)
    except BuildFailed as exc:
        status_msgs(
            exc.cause,
            "WARNING: The C extension could not be compiled, " +
            "speedups are not enabled.",
            "Failure information, if any, is above.",
            "Retrying the build without the C extension now."
        )

        run_setup(False)

        status_msgs(
            "WARNING: The C extension could not be compiled, " +
            "speedups are not enabled.",
            "Plain-Python build succeeded."
        )