# Copyright 2015 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""A setup module for the GRPC Python package."""

# NOTE(https://github.com/grpc/grpc/issues/24028): allow setuptools to monkey
# patch distutils
import setuptools  # isort:skip

# Monkey Patch the unix compiler to accept ASM
# files used by boring SSL.
from distutils.unixccompiler import UnixCCompiler

UnixCCompiler.src_extensions.append('.S')
del UnixCCompiler

from distutils import cygwinccompiler
from distutils import extension as _extension
from distutils import util
import os
import os.path
import pathlib
import platform
import re
import shlex
import shutil
import subprocess
from subprocess import PIPE
import sys
import sysconfig

import _metadata
import pkg_resources
from setuptools.command import egg_info

# Redirect the manifest template from MANIFEST.in to PYTHON-MANIFEST.in.
egg_info.manifest_maker.template = 'PYTHON-MANIFEST.in'

PY3 = sys.version_info.major == 3
PYTHON_STEM = os.path.join('src', 'python', 'grpcio')
CORE_INCLUDE = (
    'include',
    '.',
)
ABSL_INCLUDE = (os.path.join('third_party', 'abseil-cpp'),)
ADDRESS_SORTING_INCLUDE = (os.path.join('third_party', 'address_sorting',
                                        'include'),)
CARES_INCLUDE = (
    os.path.join('third_party', 'cares', 'cares', 'include'),
    os.path.join('third_party', 'cares'),
    os.path.join('third_party', 'cares', 'cares'),
)
if 'darwin' in sys.platform:
    CARES_INCLUDE += (os.path.join('third_party', 'cares', 'config_darwin'),)
if 'freebsd' in sys.platform:
    CARES_INCLUDE += (os.path.join('third_party', 'cares', 'config_freebsd'),)
if 'linux' in sys.platform:
    CARES_INCLUDE += (os.path.join('third_party', 'cares', 'config_linux'),)
if 'openbsd' in sys.platform:
    CARES_INCLUDE += (os.path.join('third_party', 'cares', 'config_openbsd'),)
RE2_INCLUDE = (os.path.join('third_party', 're2'),)
SSL_INCLUDE = (os.path.join('third_party', 'boringssl-with-bazel', 'src',
                            'include'),)
UPB_INCLUDE = (os.path.join('third_party', 'upb'),)
UPB_GRPC_GENERATED_INCLUDE = (os.path.join('src', 'core', 'ext',
                                           'upb-generated'),)
UPBDEFS_GRPC_GENERATED_INCLUDE = (os.path.join('src', 'core', 'ext',
                                               'upbdefs-generated'),)
XXHASH_INCLUDE = (os.path.join('third_party', 'xxhash'),)
ZLIB_INCLUDE = (os.path.join('third_party', 'zlib'),)
README = os.path.join(PYTHON_STEM, 'README.rst')

# Ensure we're in the proper directory whether or not we're being used by pip.
os.chdir(os.path.dirname(os.path.abspath(__file__)))
sys.path.insert(0, os.path.abspath(PYTHON_STEM))

# Break import-style to ensure we can actually find our in-repo dependencies.
import _parallel_compile_patch
import _spawn_patch
import grpc_core_dependencies

import commands
import grpc_version

_parallel_compile_patch.monkeypatch_compile_maybe()
_spawn_patch.monkeypatch_spawn()

LICENSE = 'Apache License 2.0'

CLASSIFIERS = [
    'Development Status :: 5 - Production/Stable',
    'Programming Language :: Python',
    'Programming Language :: Python :: 3',
    'Programming Language :: Python :: 3.7',
    'Programming Language :: Python :: 3.8',
    'Programming Language :: Python :: 3.9',
    'Programming Language :: Python :: 3.10',
    'Programming Language :: Python :: 3.11',
    'License :: OSI Approved :: Apache Software License',
]


def _env_bool_value(env_name, default):
    """Parses a bool option from an environment variable"""
    return os.environ.get(env_name, default).upper() not in ['FALSE', '0', '']


BUILD_WITH_BORING_SSL_ASM = _env_bool_value('GRPC_BUILD_WITH_BORING_SSL_ASM',
                                            'True')

# Export this environment variable to override the platform variant that will
# be chosen for boringssl assembly optimizations. This option is useful when
# crosscompiling and the host platform as obtained by distutils.utils.get_platform()
# doesn't match the platform we are targetting.
# Example value: "linux-aarch64"
BUILD_OVERRIDE_BORING_SSL_ASM_PLATFORM = os.environ.get(
    'GRPC_BUILD_OVERRIDE_BORING_SSL_ASM_PLATFORM', '')

# Environment variable to determine whether or not the Cython extension should
# *use* Cython or use the generated C files. Note that this requires the C files
# to have been generated by building first *with* Cython support. Even if this
# is set to false, if the script detects that the generated `.c` file isn't
# present, then it will still attempt to use Cython.
BUILD_WITH_CYTHON = _env_bool_value('GRPC_PYTHON_BUILD_WITH_CYTHON', 'False')

# Export this variable to use the system installation of openssl. You need to
# have the header files installed (in /usr/include/openssl) and during
# runtime, the shared library must be installed
BUILD_WITH_SYSTEM_OPENSSL = _env_bool_value('GRPC_PYTHON_BUILD_SYSTEM_OPENSSL',
                                            'False')

# Export this variable to use the system installation of zlib. You need to
# have the header files installed (in /usr/include/) and during
# runtime, the shared library must be installed
BUILD_WITH_SYSTEM_ZLIB = _env_bool_value('GRPC_PYTHON_BUILD_SYSTEM_ZLIB',
                                         'False')

# Export this variable to use the system installation of cares. You need to
# have the header files installed (in /usr/include/) and during
# runtime, the shared library must be installed
BUILD_WITH_SYSTEM_CARES = _env_bool_value('GRPC_PYTHON_BUILD_SYSTEM_CARES',
                                          'False')

# Export this variable to use the system installation of re2. You need to
# have the header files installed (in /usr/include/re2) and during
# runtime, the shared library must be installed
BUILD_WITH_SYSTEM_RE2 = _env_bool_value('GRPC_PYTHON_BUILD_SYSTEM_RE2', 'False')

# Export this variable to use the system installation of abseil. You need to
# have the header files installed (in /usr/include/absl) and during
# runtime, the shared library must be installed
BUILD_WITH_SYSTEM_ABSL = os.environ.get('GRPC_PYTHON_BUILD_SYSTEM_ABSL', False)

# Export this variable to force building the python extension with a statically linked libstdc++.
# At least on linux, this is normally not needed as we can build manylinux-compatible wheels on linux just fine
# without statically linking libstdc++ (which leads to a slight increase in the wheel size).
# This option is useful when crosscompiling wheels for aarch64 where
# it's difficult to ensure that the crosscompilation toolchain has a high-enough version
# of GCC (we require >=5.1) but still uses old-enough libstdc++ symbols.
# TODO(jtattermusch): remove this workaround once issues with crosscompiler version are resolved.
BUILD_WITH_STATIC_LIBSTDCXX = _env_bool_value(
    'GRPC_PYTHON_BUILD_WITH_STATIC_LIBSTDCXX', 'False')

# For local development use only: This skips building gRPC Core and its
# dependencies, including protobuf and boringssl. This allows "incremental"
# compilation by first building gRPC Core using make, then building only the
# Python/Cython layers here.
#
# Note that this requires libboringssl.a in the libs/{dbg,opt}/ directory, which
# may require configuring make to not use the system openssl implementation:
#
#    make HAS_SYSTEM_OPENSSL_ALPN=0
#
# TODO(ericgribkoff) Respect the BUILD_WITH_SYSTEM_* flags alongside this option
USE_PREBUILT_GRPC_CORE = _env_bool_value('GRPC_PYTHON_USE_PREBUILT_GRPC_CORE',
                                         'False')

# If this environmental variable is set, GRPC will not try to be compatible with
# libc versions old than the one it was compiled against.
DISABLE_LIBC_COMPATIBILITY = _env_bool_value(
    'GRPC_PYTHON_DISABLE_LIBC_COMPATIBILITY', 'False')

# Environment variable to determine whether or not to enable coverage analysis
# in Cython modules.
ENABLE_CYTHON_TRACING = _env_bool_value('GRPC_PYTHON_ENABLE_CYTHON_TRACING',
                                        'False')

# Environment variable specifying whether or not there's interest in setting up
# documentation building.
ENABLE_DOCUMENTATION_BUILD = _env_bool_value(
    'GRPC_PYTHON_ENABLE_DOCUMENTATION_BUILD', 'False')


def check_linker_need_libatomic():
    """Test if linker on system needs libatomic."""
    code_test = (b'#include <atomic>\n' +
                 b'int main() { return std::atomic<int64_t>{}; }')
    cxx = shlex.split(os.environ.get('CXX', 'c++'))
    cpp_test = subprocess.Popen(cxx + ['-x', 'c++', '-std=c++17', '-'],
                                stdin=PIPE,
                                stdout=PIPE,
                                stderr=PIPE)
    cpp_test.communicate(input=code_test)
    if cpp_test.returncode == 0:
        return False
    # Double-check to see if -latomic actually can solve the problem.
    # https://github.com/grpc/grpc/issues/22491
    cpp_test = subprocess.Popen(cxx +
                                ['-x', 'c++', '-std=c++17', '-', '-latomic'],
                                stdin=PIPE,
                                stdout=PIPE,
                                stderr=PIPE)
    cpp_test.communicate(input=code_test)
    return cpp_test.returncode == 0


# There are some situations (like on Windows) where CC, CFLAGS, and LDFLAGS are
# entirely ignored/dropped/forgotten by distutils and its Cygwin/MinGW support.
# We use these environment variables to thus get around that without locking
# ourselves in w.r.t. the multitude of operating systems this ought to build on.
# We can also use these variables as a way to inject environment-specific
# compiler/linker flags. We assume GCC-like compilers and/or MinGW as a
# reasonable default.
EXTRA_ENV_COMPILE_ARGS = os.environ.get('GRPC_PYTHON_CFLAGS', None)
EXTRA_ENV_LINK_ARGS = os.environ.get('GRPC_PYTHON_LDFLAGS', None)
if EXTRA_ENV_COMPILE_ARGS is None:
    EXTRA_ENV_COMPILE_ARGS = ' -std=c++17'
    if 'win32' in sys.platform:
        if sys.version_info < (3, 5):
            EXTRA_ENV_COMPILE_ARGS += ' -D_hypot=hypot'
            # We use define flags here and don't directly add to DEFINE_MACROS below to
            # ensure that the expert user/builder has a way of turning it off (via the
            # envvars) without adding yet more GRPC-specific envvars.
            # See https://sourceforge.net/p/mingw-w64/bugs/363/
            if '32' in platform.architecture()[0]:
                EXTRA_ENV_COMPILE_ARGS += ' -D_ftime=_ftime32 -D_timeb=__timeb32 -D_ftime_s=_ftime32_s'
            else:
                EXTRA_ENV_COMPILE_ARGS += ' -D_ftime=_ftime64 -D_timeb=__timeb64'
        else:
            # We need to statically link the C++ Runtime, only the C runtime is
            # available dynamically
            EXTRA_ENV_COMPILE_ARGS += ' /MT'
    elif "linux" in sys.platform:
        EXTRA_ENV_COMPILE_ARGS += ' -fvisibility=hidden -fno-wrapv -fno-exceptions'
    elif "darwin" in sys.platform:
        EXTRA_ENV_COMPILE_ARGS += ' -stdlib=libc++ -fvisibility=hidden -fno-wrapv -fno-exceptions -DHAVE_UNISTD_H'

if EXTRA_ENV_LINK_ARGS is None:
    EXTRA_ENV_LINK_ARGS = ''
    if "linux" in sys.platform or "darwin" in sys.platform:
        EXTRA_ENV_LINK_ARGS += ' -lpthread'
        if check_linker_need_libatomic():
            EXTRA_ENV_LINK_ARGS += ' -latomic'
    elif "win32" in sys.platform and sys.version_info < (3, 5):
        msvcr = cygwinccompiler.get_msvcr()[0]
        EXTRA_ENV_LINK_ARGS += (
            ' -static-libgcc -static-libstdc++ -mcrtdll={msvcr}'
            ' -static -lshlwapi'.format(msvcr=msvcr))
    if "linux" in sys.platform:
        EXTRA_ENV_LINK_ARGS += ' -static-libgcc'
        EXTRA_ENV_LINK_ARGS += ' -labsl_str_format_internal -labsl_time -labsl_bad_optional_access -labsl_hash -labsl_raw_hash_set -labsl_status -labsl_statusor -labsl_random_internal_randen_slow -labsl_random_internal_randen_hwaes_impl -labsl_random_internal_randen -labsl_random_internal_pool_urbg -labsl_bad_variant_access'

EXTRA_COMPILE_ARGS = shlex.split(EXTRA_ENV_COMPILE_ARGS)
EXTRA_LINK_ARGS = shlex.split(EXTRA_ENV_LINK_ARGS)

if BUILD_WITH_STATIC_LIBSTDCXX:
    EXTRA_LINK_ARGS.append('-static-libstdc++')

CYTHON_EXTENSION_PACKAGE_NAMES = ()

CYTHON_EXTENSION_MODULE_NAMES = ('grpc._cython.cygrpc',)

CYTHON_HELPER_C_FILES = ()

CORE_C_FILES = tuple(grpc_core_dependencies.CORE_SOURCE_FILES)
if "win32" in sys.platform:
    CORE_C_FILES = filter(lambda x: 'third_party/cares' not in x, CORE_C_FILES)

if BUILD_WITH_SYSTEM_OPENSSL:
    CORE_C_FILES = filter(lambda x: 'third_party/boringssl' not in x,
                          CORE_C_FILES)
    CORE_C_FILES = filter(lambda x: 'src/boringssl' not in x, CORE_C_FILES)
    SSL_INCLUDE = (os.path.join('/usr', 'include', 'openssl'),)

if BUILD_WITH_SYSTEM_ZLIB:
    CORE_C_FILES = filter(lambda x: 'third_party/zlib' not in x, CORE_C_FILES)
    ZLIB_INCLUDE = (os.path.join('/usr', 'include'),)

if BUILD_WITH_SYSTEM_CARES:
    CORE_C_FILES = filter(lambda x: 'third_party/cares' not in x, CORE_C_FILES)
    CARES_INCLUDE = (os.path.join('/usr', 'include'),)

if BUILD_WITH_SYSTEM_RE2:
    CORE_C_FILES = filter(lambda x: 'third_party/re2' not in x, CORE_C_FILES)
    RE2_INCLUDE = (os.path.join('/usr', 'include', 're2'),)

if BUILD_WITH_SYSTEM_ABSL:
    CORE_C_FILES = filter(lambda x: 'third_party/abseil-cpp' not in x,
                          CORE_C_FILES)
    ABSL_INCLUDE = (os.path.join('/usr', 'include'),)

EXTENSION_INCLUDE_DIRECTORIES = ((PYTHON_STEM,) + CORE_INCLUDE + ABSL_INCLUDE +
                                 ADDRESS_SORTING_INCLUDE + CARES_INCLUDE +
                                 RE2_INCLUDE + SSL_INCLUDE + UPB_INCLUDE +
                                 UPB_GRPC_GENERATED_INCLUDE +
                                 UPBDEFS_GRPC_GENERATED_INCLUDE +
                                 XXHASH_INCLUDE + ZLIB_INCLUDE)

EXTENSION_LIBRARIES = ()
if "linux" in sys.platform:
    EXTENSION_LIBRARIES += ('rt',)
if not "win32" in sys.platform:
    EXTENSION_LIBRARIES += ('m',)
if "win32" in sys.platform:
    EXTENSION_LIBRARIES += (
        'advapi32',
        'bcrypt',
        'dbghelp',
        'ws2_32',
    )
if BUILD_WITH_SYSTEM_OPENSSL:
    EXTENSION_LIBRARIES += (
        'ssl',
        'crypto',
    )
if BUILD_WITH_SYSTEM_ZLIB:
    EXTENSION_LIBRARIES += ('z',)
if BUILD_WITH_SYSTEM_CARES:
    EXTENSION_LIBRARIES += ('cares',)
if BUILD_WITH_SYSTEM_RE2:
    EXTENSION_LIBRARIES += ('re2',)
if BUILD_WITH_SYSTEM_ABSL:
    EXTENSION_LIBRARIES += tuple(
        lib.stem[3:] for lib in pathlib.Path('/usr').glob('lib*/libabsl_*.so'))

DEFINE_MACROS = (('_WIN32_WINNT', 0x600),)
asm_files = []


# Quotes on Windows build macros are evaluated differently from other platforms,
# so we must apply quotes asymmetrically in order to yield the proper result in
# the binary.
def _quote_build_define(argument):
    if "win32" in sys.platform:
        return '"\\\"{}\\\""'.format(argument)
    return '"{}"'.format(argument)


DEFINE_MACROS += (
    ("GRPC_XDS_USER_AGENT_NAME_SUFFIX", _quote_build_define("Python")),
    ("GRPC_XDS_USER_AGENT_VERSION_SUFFIX",
     _quote_build_define(_metadata.__version__)),
)

asm_key = ''
if BUILD_WITH_BORING_SSL_ASM and not BUILD_WITH_SYSTEM_OPENSSL:
    boringssl_asm_platform = BUILD_OVERRIDE_BORING_SSL_ASM_PLATFORM if BUILD_OVERRIDE_BORING_SSL_ASM_PLATFORM else util.get_platform(
    )
    LINUX_X86_64 = 'linux-x86_64'
    LINUX_ARM = 'linux-arm'
    LINUX_AARCH64 = 'linux-aarch64'
    if LINUX_X86_64 == boringssl_asm_platform:
        asm_key = 'crypto_linux_x86_64'
    elif LINUX_ARM == boringssl_asm_platform:
        asm_key = 'crypto_linux_arm'
    elif LINUX_AARCH64 == boringssl_asm_platform:
        asm_key = 'crypto_linux_aarch64'
    elif "mac" in boringssl_asm_platform and "x86_64" in boringssl_asm_platform:
        asm_key = 'crypto_mac_x86_64'
    else:
        print("ASM Builds for BoringSSL currently not supported on:",
              boringssl_asm_platform)
if asm_key:
    asm_files = grpc_core_dependencies.ASM_SOURCE_FILES[asm_key]
else:
    DEFINE_MACROS += (('OPENSSL_NO_ASM', 1),)

if not DISABLE_LIBC_COMPATIBILITY:
    DEFINE_MACROS += (('GPR_BACKWARDS_COMPATIBILITY_MODE', 1),)

if "win32" in sys.platform:
    # TODO(zyc): Re-enable c-ares on x64 and x86 windows after fixing the
    # ares_library_init compilation issue
    DEFINE_MACROS += (
        ('WIN32_LEAN_AND_MEAN', 1),
        ('CARES_STATICLIB', 1),
        ('GRPC_ARES', 0),
        ('NTDDI_VERSION', 0x06000000),
        ('NOMINMAX', 1),
    )
    if '64bit' in platform.architecture()[0]:
        DEFINE_MACROS += (('MS_WIN64', 1),)
    elif sys.version_info >= (3, 5):
        # For some reason, this is needed to get access to inet_pton/inet_ntop
        # on msvc, but only for 32 bits
        DEFINE_MACROS += (('NTDDI_VERSION', 0x06000000),)
else:
    DEFINE_MACROS += (
        ('HAVE_CONFIG_H', 1),
        ('GRPC_ENABLE_FORK_SUPPORT', 1),
    )

LDFLAGS = tuple(EXTRA_LINK_ARGS)
CFLAGS = tuple(EXTRA_COMPILE_ARGS)
if "linux" in sys.platform or "darwin" in sys.platform:
    pymodinit_type = 'PyObject*' if PY3 else 'void'
    pymodinit = 'extern "C" __attribute__((visibility ("default"))) {}'.format(
        pymodinit_type)
    DEFINE_MACROS += (('PyMODINIT_FUNC', pymodinit),)
    DEFINE_MACROS += (('GRPC_POSIX_FORK_ALLOW_PTHREAD_ATFORK', 1),)

# By default, Python3 distutils enforces compatibility of
# c plugins (.so files) with the OSX version Python was built with.
# We need OSX 10.10, the oldest which supports C++ thread_local.
# Python 3.9: Mac OS Big Sur sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET') returns int (11)
if 'darwin' in sys.platform:
    mac_target = sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET')
    if mac_target:
        mac_target = pkg_resources.parse_version(str(mac_target))
        if mac_target < pkg_resources.parse_version('10.10.0'):
            os.environ['MACOSX_DEPLOYMENT_TARGET'] = '10.10'
            os.environ['_PYTHON_HOST_PLATFORM'] = re.sub(
                r'macosx-[0-9]+\.[0-9]+-(.+)', r'macosx-10.10-\1',
                util.get_platform())


def cython_extensions_and_necessity():
    cython_module_files = [
        os.path.join(PYTHON_STEM,
                     name.replace('.', '/') + '.pyx')
        for name in CYTHON_EXTENSION_MODULE_NAMES
    ]
    config = os.environ.get('CONFIG', 'opt')
    prefix = 'libs/' + config + '/'
    if USE_PREBUILT_GRPC_CORE:
        extra_objects = [
            prefix + 'libares.a', prefix + 'libboringssl.a',
            prefix + 'libgpr.a', prefix + 'libgrpc.a'
        ]
        core_c_files = []
    else:
        core_c_files = list(CORE_C_FILES)
        extra_objects = []
    extensions = [
        _extension.Extension(
            name=module_name,
            sources=([module_file] + list(CYTHON_HELPER_C_FILES) +
                     core_c_files + asm_files),
            include_dirs=list(EXTENSION_INCLUDE_DIRECTORIES),
            libraries=list(EXTENSION_LIBRARIES),
            define_macros=list(DEFINE_MACROS),
            extra_objects=extra_objects,
            extra_compile_args=list(CFLAGS),
            extra_link_args=list(LDFLAGS),
        ) for (module_name, module_file
              ) in zip(list(CYTHON_EXTENSION_MODULE_NAMES), cython_module_files)
    ]
    need_cython = BUILD_WITH_CYTHON
    if not BUILD_WITH_CYTHON:
        need_cython = need_cython or not commands.check_and_update_cythonization(
            extensions)
    # TODO: the strategy for conditional compiling and exposing the aio Cython
    # dependencies will be revisited by https://github.com/grpc/grpc/issues/19728
    return commands.try_cythonize(extensions,
                                  linetracing=ENABLE_CYTHON_TRACING,
                                  mandatory=BUILD_WITH_CYTHON), need_cython


CYTHON_EXTENSION_MODULES, need_cython = cython_extensions_and_necessity()

PACKAGE_DIRECTORIES = {
    '': PYTHON_STEM,
}

INSTALL_REQUIRES = ()

EXTRAS_REQUIRES = {
    'protobuf': 'grpcio-tools>={version}'.format(version=grpc_version.VERSION),
}

SETUP_REQUIRES = INSTALL_REQUIRES + (
    'Sphinx',) if ENABLE_DOCUMENTATION_BUILD else ()

try:
    import Cython
except ImportError:
    if BUILD_WITH_CYTHON:
        sys.stderr.write(
            "You requested a Cython build via GRPC_PYTHON_BUILD_WITH_CYTHON, "
            "but do not have Cython installed. We won't stop you from using "
            "other commands, but the extension files will fail to build.\n")
    elif need_cython:
        sys.stderr.write(
            'We could not find Cython. Setup may take 10-20 minutes.\n')
        SETUP_REQUIRES += ('cython>=3.0.0',)

COMMAND_CLASS = {
    'doc': commands.SphinxDocumentation,
    'build_project_metadata': commands.BuildProjectMetadata,
    'build_py': commands.BuildPy,
    'build_ext': commands.BuildExt,
    'gather': commands.Gather,
    'clean': commands.Clean,
}

# Ensure that package data is copied over before any commands have been run:
credentials_dir = os.path.join(PYTHON_STEM, 'grpc', '_cython', '_credentials')
try:
    os.mkdir(credentials_dir)
except OSError:
    pass
shutil.copyfile(os.path.join('etc', 'roots.pem'),
                os.path.join(credentials_dir, 'roots.pem'))

PACKAGE_DATA = {
    # Binaries that may or may not be present in the final installation, but are
    # mentioned here for completeness.
    'grpc._cython': [
        '_credentials/roots.pem',
        '_windows/grpc_c.32.python',
        '_windows/grpc_c.64.python',
    ],
}
PACKAGES = setuptools.find_packages(PYTHON_STEM)

setuptools.setup(
    name='grpcio',
    version=grpc_version.VERSION,
    description='HTTP/2-based RPC framework',
    author='The gRPC Authors',
    author_email='grpc-io@googlegroups.com',
    url='https://grpc.io',
    license=LICENSE,
    classifiers=CLASSIFIERS,
    long_description=open(README).read(),
    ext_modules=CYTHON_EXTENSION_MODULES,
    packages=list(PACKAGES),
    package_dir=PACKAGE_DIRECTORIES,
    package_data=PACKAGE_DATA,
    python_requires='>=3.7',
    install_requires=INSTALL_REQUIRES,
    extras_require=EXTRAS_REQUIRES,
    setup_requires=SETUP_REQUIRES,
    cmdclass=COMMAND_CLASS,
)