Add importlib_metadata to compat.py and discover_entry_points to import_tools.py

Author: domdfcoding

.isort.cfg

@@ -20,6 +20,7 @@ known_third_party =
     enum_tools
     faker
     github
+    importlib_metadata
     importlib_resources
     iniconfig
     pandas

domdf_python_tools/compat.py

@@ -12,6 +12,13 @@
 
 	`importlib_resources <https://importlib-resources.readthedocs.io/en/latest/>`_ on Python 3.6;
 	:mod:`importlib.resources` on Python 3.7 and later.
+
+.. py:data:: importlib_metadata
+
+	`importlib_metadata <https://importlib-metadata.readthedocs.io/en/latest/>`_ on Python 3.7 and earlier;
+	:mod:`importlib.metadata` on Python 3.8 and later.
+
+	.. versionadded:: 1.1.0
 """
 #
 #  Copyright © 2020 Dominic Davis-Foster <dominic@davis-foster.co.uk>
@@ -35,11 +42,19 @@
 # stdlib
 import sys
 
-__all__ = ["importlib_resources"]
+__all__ = ["importlib_resources", "importlib_metadata"]
 
 if sys.version_info < (3, 7):  # pragma: no cover (>=py37)
 	# 3rd party
 	import importlib_resources
 else:  # pragma: no cover (<py37)
 	# stdlib
 	import importlib.resources as importlib_resources
+
+
+if sys.version_info[:2] < (3, 8):  # pragma: no cover (>=py38)
+	# 3rd party
+	import importlib_metadata  # type: ignore
+else:  # pragma: no cover (<py38)
+	# stdlib
+	import importlib.metadata as importlib_metadata

domdf_python_tools/import_tools.py

@@ -53,6 +53,8 @@
 # 3rd party
 from typing_extensions import Literal
 
+from domdf_python_tools.compat import importlib_metadata
+
 __all__ = ["discover"]
 
 
@@ -80,10 +82,11 @@ def discover(
 		exclude_side_effects: bool = True,
 		) -> List[Any]:
 	"""
-	Returns a list of objects in the directory matched by ``match_func``.
+	Returns a list of objects in the given module,
+	optionally filtered by ``match_func``.
 
 	:param package: A Python package
-	:param match_func: Function taking an object and returning true if the object is to be included in the output.
+	:param match_func: Function taking an object and returning :py:obj:`True` if the object is to be included in the output.
 	:default match_func: :py:obj:`None`, which includes all objects.
 	:param exclude_side_effects: Don't include objects that are only there because of an import side effect.
 
@@ -94,7 +97,7 @@ def discover(
 		Added the ``exclude_side_effects`` parameter.
 	"""
 
-	matched_classes = list()
+	matching_objects = []
 
 	for _, module_name, _ in pkgutil.walk_packages(
 		# https://github.com/python/mypy/issues/1422
@@ -114,9 +117,9 @@ def discover(
 				if imported_objects.__module__ != module.__name__:
 					continue
 
-			matched_classes.append(imported_objects)
+			matching_objects.append(imported_objects)
 
-	return matched_classes
+	return matching_objects
 
 
 #
@@ -132,3 +135,33 @@ def discover(
 # 	spec.loader.exec_module(mod)
 # 	sys.modules[mod.__name__] = mod
 # 	return mod
+
+
+def discover_entry_points(
+		group_name: str,
+		match_func: Optional[Callable[[Any], bool]] = None,
+		) -> List[Any]:
+	"""
+	Returns a list of entry points in the given category,
+	optionally filtered by ``match_func``.
+
+	:param group_name: The entry point group name, e.g. ``'entry_points'``.
+	:param match_func: Function taking an object and returning :py:obj:`True` if the object is to be included in the output.
+	:default match_func: :py:obj:`None`, which includes all objects.
+
+	:return: List of matching objects.
+
+	.. versionadded:: 1.1.0
+	"""
+
+	matching_objects = []
+
+	for entry_point in importlib_metadata.entry_points().get(group_name, ()):
+		entry_point = entry_point.load()
+
+		if match_func is not None and not match_func(entry_point):
+			continue
+
+		matching_objects.append(entry_point)
+
+	return matching_objects

requirements.txt

@@ -1,5 +1,6 @@
 colorama>=0.4.3
 deprecation>=2.1.0
 importlib_resources>=3.0.0; python_version < "3.7"
+importlib_metadata>=1.5.0; python_version < "3.8"
 pydash>=4.7.4
 typing_extensions>=3.7.4.3