[Python Modernization] Deprecate pkg_resources (grpc#35849)

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Closes grpc#35849

PiperOrigin-RevId: 607144827

setup.py

@@ -37,7 +37,6 @@
 import sysconfig
 
 import _metadata
-import pkg_resources
 from setuptools import Extension
 from setuptools.command import egg_info
 
@@ -454,22 +453,6 @@ def _quote_build_define(argument):
     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",
-                sysconfig.get_platform(),
-            )
-
 
 def cython_extensions_and_necessity():
     cython_module_files = [

src/python/grpcio/README.rst

@@ -72,32 +72,6 @@ Troubleshooting
 
 Help, I ...
 
-* **... see a** :code:`pkg_resources.VersionConflict` **when I try to install
-  grpc**
-
-  This is likely because :code:`pip` doesn't own the offending dependency,
-  which in turn is likely because your operating system's package manager owns
-  it. You'll need to force the installation of the dependency:
-
-  :code:`pip install --ignore-installed $OFFENDING_DEPENDENCY`
-
-  For example, if you get an error like the following:
-
-  ::
-
-    Traceback (most recent call last):
-    File "<string>", line 17, in <module>
-     ...
-    File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 509, in find
-      raise VersionConflict(dist, req)
-    pkg_resources.VersionConflict: (six 1.8.0 (/usr/lib/python2.7/dist-packages), Requirement.parse('six>=1.10'))
-
-  You can fix it by doing:
-
-  ::
-
-    sudo pip install --ignore-installed six
-
 * **... see the following error on some platforms**
 
   ::

src/python/grpcio_observability/setup.py

@@ -22,7 +22,6 @@
 import sys
 import sysconfig
 
-import pkg_resources
 import setuptools
 from setuptools import Extension
 from setuptools.command import build_ext
@@ -206,22 +205,6 @@ def get_ext_filename(self, ext_name):
     pymodinit = 'extern "C" __attribute__((visibility ("default"))) PyObject*'
     DEFINE_MACROS += (("PyMODINIT_FUNC", pymodinit),)
 
-# 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.
-if "darwin" in sys.platform:
-    mac_target = sysconfig.get_config_var("MACOSX_DEPLOYMENT_TARGET")
-    if mac_target and (
-        pkg_resources.parse_version(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",
-            sysconfig.get_platform(),
-        )
-
 
 def extension_modules():
     if BUILD_WITH_CYTHON:

src/python/grpcio_tests/tests/protoc_plugin/_split_definitions_test.py

@@ -26,7 +26,12 @@
 
 import grpc
 from grpc_tools import protoc
-import pkg_resources
+
+if sys.version_info >= (3, 9, 0):
+    from importlib import resources
+else:
+    import pkg_resources
+
 
 from tests.unit import test_common
 
@@ -48,6 +53,22 @@ def _system_path(path_insertion):
     sys.path = old_system_path
 
 
+def _get_resource_file_name(
+    package_or_requirement: str, resource_name: str
+) -> str:
+    """Obtain the filename for a resource on the file system."""
+    file_name = None
+    if sys.version_info >= (3, 9, 0):
+        file_name = (
+            resources.files(package_or_requirement) / resource_name
+        ).resolve()
+    else:
+        file_name = pkg_resources.resource_filename(
+            package_or_requirement, resource_name
+        )
+    return str(file_name)
+
+
 # NOTE(nathaniel): https://twitter.com/exoplaneteer/status/677259364256747520
 # Life lesson "just always default to idempotence" reinforced.
 def _create_directory_tree(root, path_components_sequence):
@@ -367,7 +388,7 @@ class WellKnownTypesTest(unittest.TestCase):
     def testWellKnownTypes(self):
         os.chdir(_TEST_DIR)
         out_dir = tempfile.mkdtemp(suffix="wkt_test", dir=".")
-        well_known_protos_include = pkg_resources.resource_filename(
+        well_known_protos_include = _get_resource_file_name(
             "grpc_tools", "_proto"
         )
         args = [

tools/distrib/python/grpcio_tools/README.rst

@@ -75,32 +75,6 @@ Troubleshooting
 
 Help, I ...
 
-* **... see a** :code:`pkg_resources.VersionConflict` **when I try to install
-  grpc**
-
-  This is likely because :code:`pip` doesn't own the offending dependency,
-  which in turn is likely because your operating system's package manager owns
-  it. You'll need to force the installation of the dependency:
-
-  :code:`pip install --ignore-installed $OFFENDING_DEPENDENCY`
-
-  For example, if you get an error like the following:
-
-  ::
-
-    Traceback (most recent call last):
-    File "<string>", line 17, in <module>
-     ...
-    File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 509, in find
-      raise VersionConflict(dist, req)
-    pkg_resources.VersionConflict: (six 1.8.0 (/usr/lib/python2.7/dist-packages), Requirement.parse('six>=1.10'))
-
-  You can fix it by doing:
-
-  ::
-
-    sudo pip install --ignore-installed six
-
 * **... see compiler errors on some platforms when either installing from source or from the source distribution**
 
   If you see

tools/distrib/python/grpcio_tools/grpc_tools/command.py

@@ -16,9 +16,29 @@
 import sys
 
 from grpc_tools import protoc
-import pkg_resources
 import setuptools
 
+if sys.version_info >= (3, 9, 0):
+    from importlib import resources
+else:
+    import pkg_resources
+
+
+def _get_resource_file_name(
+    package_or_requirement: str, resource_name: str
+) -> str:
+    """Obtain the filename for a resource on the file system."""
+    file_name = None
+    if sys.version_info >= (3, 9, 0):
+        file_name = (
+            resources.files(package_or_requirement) / resource_name
+        ).resolve()
+    else:
+        file_name = pkg_resources.resource_filename(
+            package_or_requirement, resource_name
+        )
+    return str(file_name)
+
 
 def build_package_protos(package_root, strict_mode=False):
     proto_files = []
@@ -30,9 +50,7 @@ def build_package_protos(package_root, strict_mode=False):
                     os.path.abspath(os.path.join(root, filename))
                 )
 
-    well_known_protos_include = pkg_resources.resource_filename(
-        "grpc_tools", "_proto"
-    )
+    well_known_protos_include = _get_resource_file_name("grpc_tools", "_proto")
 
     for proto_file in proto_files:
         command = [

tools/distrib/python/grpcio_tools/setup.py

@@ -24,7 +24,6 @@
 import sys
 import sysconfig
 
-import pkg_resources
 import setuptools
 from setuptools import Extension
 from setuptools.command import build_ext
@@ -214,22 +213,6 @@ def get_ext_filename(self, ext_name):
 elif "linux" in sys.platform or "darwin" in sys.platform:
     DEFINE_MACROS += (("HAVE_PTHREAD", 1),)
 
-# By default, Python3 setuptools(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.
-if "darwin" in sys.platform:
-    mac_target = sysconfig.get_config_var("MACOSX_DEPLOYMENT_TARGET")
-    if mac_target and (
-        pkg_resources.parse_version(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",
-            sysconfig.get_platform(),
-        )
-
 
 def package_data():
     tools_path = GRPC_PYTHON_TOOLS_PACKAGE.replace(".", os.path.sep)

tools/distrib/python/xds_protos/build.py

@@ -15,15 +15,36 @@
 """Builds the content of xds-protos package"""
 
 import os
+import sys
 
 from grpc_tools import protoc
-import pkg_resources
+
+if sys.version_info >= (3, 9, 0):
+    from importlib import resources
+else:
+    import pkg_resources
 
 
 def localize_path(p):
     return os.path.join(*p.split("/"))
 
 
+def _get_resource_file_name(
+    package_or_requirement: str, resource_name: str
+) -> str:
+    """Obtain the filename for a resource on the file system."""
+    file_name = None
+    if sys.version_info >= (3, 9, 0):
+        file_name = (
+            resources.files(package_or_requirement) / resource_name
+        ).resolve()
+    else:
+        file_name = pkg_resources.resource_filename(
+            package_or_requirement, resource_name
+        )
+    return str(file_name)
+
+
 # We might not want to compile all the protos
 EXCLUDE_PROTO_PACKAGES_LIST = tuple(
     localize_path(p)
@@ -46,7 +67,7 @@ def localize_path(p):
     GRPC_ROOT, "third_party", "opencensus-proto", "src"
 )
 OPENTELEMETRY_PROTO_ROOT = os.path.join(GRPC_ROOT, "third_party", "opentelemetry")
-WELL_KNOWN_PROTOS_INCLUDE = pkg_resources.resource_filename("grpc_tools", "_proto")
+WELL_KNOWN_PROTOS_INCLUDE = _get_resource_file_name("grpc_tools", "_proto")
 
 OUTPUT_PATH = WORK_DIR