Switch from entrypoints to importlib.metadata

Since the minimum Python version supported now directly supports
querying entry points using the standard library, write a wrapper around
to support both upstream APIs, and make use of it, rather than the
external entrypoints package.

Author: s-t-e-v-e-n-k

MANIFEST.in

@@ -20,6 +20,9 @@ include *.toml
 
 include .bumpversion.cfg
 
+include papermill/tests/fixtures/foo-0.0.1.dist-info/METADATA
+include papermill/tests/fixtures/foo-0.0.1.dist-info/entry_points.txt
+
 # Documentation
 prune docs
 

papermill/engines.py

@@ -4,13 +4,12 @@
 from functools import wraps
 
 import dateutil
-import entrypoints
 
 from .clientwrap import PapermillNotebookClient
 from .exceptions import PapermillException
 from .iorw import write_ipynb
 from .log import logger
-from .utils import merge_kwargs, nb_kernel_name, nb_language, remove_args
+from .utils import get_entrypoints_group, merge_kwargs, nb_kernel_name, nb_language, remove_args
 
 
 class PapermillEngines:
@@ -33,7 +32,7 @@ def register_entry_points(self):
 
         Load handlers provided by other packages
         """
-        for entrypoint in entrypoints.get_group_all("papermill.engine"):
+        for entrypoint in get_entrypoints_group("papermill.engine"):
             self.register(entrypoint.name, entrypoint.load())
 
     def get_engine(self, name=None):

papermill/iorw.py

@@ -5,7 +5,6 @@
 import warnings
 from contextlib import contextmanager
 
-import entrypoints
 import nbformat
 import requests
 import yaml
@@ -18,7 +17,7 @@
     missing_environment_variable_generator,
 )
 from .log import logger
-from .utils import chdir
+from .utils import chdir, get_entrypoints_group
 from .version import version as __version__
 
 try:
@@ -116,7 +115,7 @@ def register(self, scheme, handler):
 
     def register_entry_points(self):
         # Load handlers provided by other packages
-        for entrypoint in entrypoints.get_group_all("papermill.io"):
+        for entrypoint in get_entrypoints_group("papermill.io"):
             self.register(entrypoint.name, entrypoint.load())
 
     def get_handler(self, path, extensions=None):

papermill/tests/fixtures/foo-0.0.1.dist-info/METADATA

@@ -0,0 +1,3 @@
+Metadata-Version: 2.3
+Name: foo
+Version: 0.0.1

papermill/tests/fixtures/foo-0.0.1.dist-info/entry_points.txt

@@ -0,0 +1,2 @@
+[papermill.tests.fake]
+foo = bar

papermill/tests/test_engines.py

@@ -492,7 +492,8 @@ def test_registering_entry_points(self):
         fake_entrypoint = Mock(load=Mock())
         fake_entrypoint.name = "fake-engine"
 
-        with patch("entrypoints.get_group_all", return_value=[fake_entrypoint]) as mock_get_group_all:
+        entry_points = {"papermill.engine": [fake_entrypoint]}
+        with patch("papermill.utils.entry_points", return_value=entry_points) as mock_entry_points:
             self.papermill_engines.register_entry_points()
-            mock_get_group_all.assert_called_once_with("papermill.engine")
+            mock_entry_points.assert_called_once()
             self.assertEqual(self.papermill_engines.get_engine("fake-engine"), fake_entrypoint.load.return_value)

papermill/tests/test_iorw.py

@@ -104,9 +104,10 @@ def test_entrypoint_register(self):
         fake_entrypoint = Mock(load=Mock())
         fake_entrypoint.name = "fake-from-entry-point://"
 
-        with patch("entrypoints.get_group_all", return_value=[fake_entrypoint]) as mock_get_group_all:
+        entry_points = {"papermill.io": [fake_entrypoint]}
+        with patch("papermill.utils.entry_points", return_value=entry_points) as mock_entry_points:
             self.papermill_io.register_entry_points()
-            mock_get_group_all.assert_called_once_with("papermill.io")
+            mock_entry_points.assert_called_once()
             fake_ = self.papermill_io.get_handler("fake-from-entry-point://")
             assert fake_ == fake_entrypoint.load.return_value
 

papermill/tests/test_utils.py

@@ -1,3 +1,4 @@
+import sys
 import warnings
 from pathlib import Path
 from tempfile import TemporaryDirectory
@@ -10,6 +11,7 @@
 from ..utils import (
     any_tagged_cell,
     chdir,
+    get_entrypoints_group,
     merge_kwargs,
     remove_args,
     retry,
@@ -58,3 +60,14 @@ def test_chdir():
             assert Path.cwd() == Path(temp_dir)
 
     assert Path.cwd() == old_cwd
+
+
+def test_get_entrypoints_group():
+    # We don't need to mock anything here, there is just enough metadata
+    # present to give us one entry point.
+    sys.path.insert(0, Path(__file__).parent / "fixtures")
+    # We need to cast to a list here, 3.8/3.9 and 3.10+ return different
+    # types.
+    eps = list(get_entrypoints_group("papermill.tests.fake"))
+    sys.path.pop()
+    assert eps[0].name == "foo"

papermill/utils.py

@@ -3,6 +3,7 @@
 import warnings
 from contextlib import contextmanager
 from functools import wraps
+from importlib.metadata import entry_points
 
 from .exceptions import PapermillParameterOverwriteWarning
 
@@ -190,3 +191,20 @@ def chdir(path):
             yield
         finally:
             os.chdir(old_dir)
+
+
+def get_entrypoints_group(group):
+    """Return a given group of entrypoints.
+
+    Since the importlib.metadata entry points API is very simple in 3.8 and
+    more complete in 3.10+, we need to support both. This function can be
+    removed when 3.10 is the minimum supported version, and replaced
+    with ``entry_points(group=group)``.
+    """
+    eps = entry_points()
+    if hasattr(eps, "select"):
+        # New and shiny Python 3.10+ API
+        return eps.select(group=group)
+    else:
+        # Python 3.8 and 3.9
+        return eps.get(group, [])

requirements.txt

@@ -4,7 +4,6 @@ nbformat >= 5.2.0
 nbclient >= 0.2.0
 tqdm >= 4.32.2
 requests
-entrypoints
 tenacity >= 5.0.2
 aiohttp >=3.9.0; python_version=="3.12"
 ansicolors