torchx: use importlib_metadata for Python 3.10+ syntax (#623)

Summary:
importlib.metadata in 3.12 breaks compatibility with the dict style interface. This switches TorchX to use importlib_metadata for all versions and switches the code to use the 3.10+ select style interface instead of dict.

This avoids having to pin importlib_metadata<5 such as in pytorch/tutorials#2091

Pull Request resolved: #623

Test Plan: Unit tests on both importlib_metadata 5.0 and 4.1.3

Reviewed By: priyaramani

Differential Revision: D40561638

Pulled By: d4l3k

fbshipit-source-id: 95144406c0e3dcbe203ada3ff3236f7384ab2a5c

dev-requirements.txt

@@ -7,7 +7,6 @@ classy-vision>=0.6.0
 flake8==3.9.0
 fsspec[s3]==2022.1.0
 hydra-core
-importlib-metadata<5.0
 ipython
 kfp==1.8.9
 moto==3.0.2

requirements.txt

@@ -1,5 +1,6 @@
 pyre-extensions
 docstring-parser==0.8.1
+importlib-metadata
 pyyaml
 docker
 filelock

setup.py

@@ -82,9 +82,6 @@ def get_nightly_version():
             "kubernetes": ["kubernetes>=11"],
             "ray": ["ray>=1.12.1"],
             "dev": dev_reqs,
-            ':python_version < "3.8"': [
-                "importlib-metadata",
-            ],
         },
         # PyPI package information.
         classifiers=[

torchx/util/entrypoints.py

@@ -4,14 +4,11 @@
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
 
-try:
-    from importlib import metadata
-    from importlib.metadata import EntryPoint
-except ImportError:
-    import importlib_metadata as metadata
-    from importlib_metadata import EntryPoint
 from typing import Any, Dict, Optional
 
+import importlib_metadata as metadata
+from importlib_metadata import EntryPoint
+
 
 # pyre-ignore-all-errors[3, 2]
 def load(group: str, name: str, default=None):
@@ -31,18 +28,13 @@ def load(group: str, name: str, default=None):
     raises an error.
     """
 
-    entrypoints = metadata.entry_points()
+    entrypoints = metadata.entry_points().select(group=group)
 
-    if group not in entrypoints and default:
+    if name not in entrypoints.names and default is not None:
         return default
 
-    eps: Dict[str, EntryPoint] = {ep.name: ep for ep in entrypoints[group]}
-
-    if name not in eps and default:
-        return default
-    else:
-        ep = eps[name]
-        return ep.load()
+    ep = entrypoints[name]
+    return ep.load()
 
 
 def _defer_load_ep(ep: EntryPoint) -> object:
@@ -75,12 +67,12 @@ def load_group(
 
     """
 
-    entrypoints = metadata.entry_points()
+    entrypoints = metadata.entry_points().select(group=group)
 
-    if group not in entrypoints:
+    if len(entrypoints) == 0:
         return default
 
     eps = {}
-    for ep in entrypoints[group]:
+    for ep in entrypoints:
         eps[ep.name] = _defer_load_ep(ep)
     return eps

torchx/util/test/entrypoints_test.py

@@ -5,15 +5,12 @@
 # LICENSE file in the root directory of this source tree.
 
 import unittest
-
-try:
-    from importlib.metadata import EntryPoint
-except ImportError:
-    from importlib_metadata import EntryPoint
 from configparser import ConfigParser
-from typing import Dict, List
+from typing import List
 from unittest.mock import MagicMock, patch
 
+from importlib_metadata import EntryPoint, EntryPoints
+
 from torchx.util.entrypoints import load, load_group
 
 
@@ -61,12 +58,12 @@ def barbaz() -> str:
 [ep.grp.missing.mod.test]
 baz = torchx.util.test.entrypoints_test.missing_module
 """
-_ENTRY_POINTS: Dict[str, List[EntryPoint]] = {
-    "entrypoints.test": EntryPoint_from_text(_EP_TXT),
-    "ep.grp.test": EntryPoint_from_text(_EP_GRP_TXT),
-    "ep.grp.missing.attr.test": EntryPoint_from_text(_EP_GRP_IGN_ATTR_TXT),
-    "ep.grp.missing.mod.test": EntryPoint_from_text(_EP_GRP_IGN_MOD_TXT),
-}
+_ENTRY_POINTS: EntryPoints = EntryPoints(
+    EntryPoint_from_text(_EP_TXT)
+    + EntryPoint_from_text(_EP_GRP_TXT)
+    + EntryPoint_from_text(_EP_GRP_IGN_ATTR_TXT)
+    + EntryPoint_from_text(_EP_GRP_IGN_MOD_TXT)
+)
 
 _METADATA_EPS: str = "torchx.util.entrypoints.metadata.entry_points"
 
@@ -77,6 +74,9 @@ def test_load(self, mock_md_eps: MagicMock) -> None:
         print(type(load("entrypoints.test", "foo")))
         self.assertEqual("foobar", load("entrypoints.test", "foo")())
 
+        with self.assertRaisesRegex(KeyError, "baz"):
+            load("entrypoints.test", "baz")()
+
     @patch(_METADATA_EPS, return_value=_ENTRY_POINTS)
     def test_load_with_default(self, mock_md_eps: MagicMock) -> None:
         self.assertEqual("barbaz", load("entrypoints.test", "missing", barbaz)())
@@ -86,7 +86,7 @@ def test_load_with_default(self, mock_md_eps: MagicMock) -> None:
     @patch(_METADATA_EPS, return_value=_ENTRY_POINTS)
     def test_load_group(self, mock_md_eps: MagicMock) -> None:
         eps = load_group("ep.grp.test")
-        self.assertEqual(2, len(eps))
+        self.assertEqual(2, len(eps), eps)
         self.assertEqual("foobar", eps["foo"]())
         self.assertEqual("barbaz", eps["bar"]())