databind.core/: improvement: Support Python 3.12 by using importlib.metadata instead of pkg_resources in Python 3.10 and newer (#55)

* databind.core/: improvement: Support Python 3.12 by using `importlib.metadata` instead of `pkg_resources` in Python 3.10 and newer

* Updated PR references in 1 changelogs.

skip-checks: true

* include 3.12 in tests

* fix mypy

---------

Co-authored-by: GitHub Action <[email protected]>

Author: NiklasRosenstein

.github/workflows/python.yaml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "3.x"]
+        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.x"]
     steps:
     - uses: actions/checkout@v2
     - uses: NiklasRosenstein/slap@gha/install/v1

databind.core/.changelog/_unreleased.toml

@@ -0,0 +1,6 @@
+[[entries]]
+id = "765031c7-ffd8-4078-8e54-4e5e9154f036"
+type = "improvement"
+description = "Support Python 3.12 by using `importlib.metadata` instead of `pkg_resources` in Python 3.10 and newer"
+author = "@NiklasRosenstein"
+pr = "https://github.com/NiklasRosenstein/python-databind/pull/55"

databind.core/pyproject.toml

@@ -18,6 +18,7 @@ python = "^3.6.3"
 Deprecated = "^1.2.12"
 nr-date = "^2.0.0"
 nr-stream = "^1.0.0"
+setuptools = { version = ">=40.8.0", markers = "python_version < '3.10'" }
 typeapi = "^2.0.1"
 typing-extensions = ">=3.10.0,<4.7"  # See https://github.com/python/typing_extensions/issues/265#issuecomment-1616809112
 

databind.core/src/databind/core/union.py

@@ -3,14 +3,23 @@
 import abc
 import dataclasses
 import importlib
+import sys
 import types
 import typing as t
 
-import pkg_resources
 from typeapi import ClassTypeHint, TypeHint
 
 from databind.core.utils import T
 
+if sys.version_info[:2] < (3, 10):
+    from pkg_resources import EntryPoint, iter_entry_points
+else:
+    from importlib.metadata import EntryPoint, entry_points
+
+    def iter_entry_points(group: str) -> t.Iterator[EntryPoint]:
+        return iter(entry_points(group=group))
+
+
 __all__ = ["UnionMembers", "StaticUnionMembers", "EntrypointUnionMembers", "ImportUnionMembers", "ChainUnionMembers"]
 
 
@@ -126,13 +135,13 @@ class EntrypointUnionMembers(UnionMembers):
     group: str
 
     def __post_init__(self) -> None:
-        self._entrypoints_cache: t.Optional[t.Dict[str, pkg_resources.EntryPoint]] = None
+        self._entrypoints_cache: t.Optional[t.Dict[str, EntryPoint]] = None
 
     @property
-    def _entrypoints(self) -> t.Dict[str, pkg_resources.EntryPoint]:
+    def _entrypoints(self) -> t.Dict[str, EntryPoint]:
         if self._entrypoints_cache is None:
             self._entrypoints_cache = {}
-            for ep in pkg_resources.iter_entry_points(self.group):
+            for ep in iter_entry_points(self.group):
                 self._entrypoints_cache[ep.name] = ep
         return self._entrypoints_cache