MOTOR-902 Since Python 3.10 asyncio.get_event_loop() is deprecated (#155

)

.github/workflows/test-python.yml

@@ -39,7 +39,7 @@ jobs:
           mongod --fork --dbpath=$(pwd)/data --logpath=$PWD/mongo.log --setParameter enableTestCommands=1
       - name: Install Python dependencies
         run: |
-          python -m pip install -U pip tox tox-gh-actions
+          python -m pip install -U pip tox tox-gh-actions setuptools
       - name: Run tests
         run: |
           tox

doc/examples/aiohttp_example.py

@@ -41,8 +41,7 @@ async def page_handler(request):
 # -- handler-end --
 
 # -- main-start --
-loop = asyncio.get_event_loop()
-db = loop.run_until_complete(setup_db())
+db = asyncio.run(setup_db())
 app = web.Application()
 app["db"] = db
 # Route requests to the page_handler() coroutine.

doc/examples/aiohttp_gridfs_example.py

@@ -33,7 +33,7 @@ async def put_gridfile():
         )
 
 
-asyncio.get_event_loop().run_until_complete(put_gridfile())
+asyncio.run(put_gridfile())
 
 
 # Add "Content-Encoding: gzip" header for compressed data.

doc/examples/auto_csfle_example.py

@@ -98,5 +98,4 @@ async def main():
 
 
 if __name__ == "__main__":
-    loop = asyncio.get_event_loop()
-    loop.run_until_complete(main())
+    asyncio.run(main())

doc/examples/explicit_encryption_automatic_decryption_example.py

@@ -73,5 +73,4 @@ async def main():
 
 
 if __name__ == "__main__":
-    loop = asyncio.get_event_loop()
-    loop.run_until_complete(main())
+    asyncio.run(main())

doc/examples/explicit_encryption_example.py

@@ -65,5 +65,4 @@ async def main():
 
 
 if __name__ == "__main__":
-    loop = asyncio.get_event_loop()
-    loop.run_until_complete(main())
+    asyncio.run(main())

doc/examples/server_fle_enforcement_example.py

@@ -97,5 +97,4 @@ async def main():
 
 
 if __name__ == "__main__":
-    loop = asyncio.get_event_loop()
-    loop.run_until_complete(main())
+    asyncio.run(main())

doc/tutorial-asyncio.rst

@@ -12,14 +12,16 @@ Tutorial: Using Motor With :mod:`asyncio`
   import pymongo
   import motor.motor_asyncio
   import asyncio
-  db = motor.motor_asyncio.AsyncIOMotorClient().test_database
+  client = motor.motor_asyncio.AsyncIOMotorClient()
+  db = client.test_database
 
 .. testsetup:: after-inserting-2000-docs
 
   import pymongo
   import motor.motor_asyncio
   import asyncio
-  db = motor.motor_asyncio.AsyncIOMotorClient().test_database
+  client = motor.motor_asyncio.AsyncIOMotorClient()
+  db = client.test_database
   pymongo.MongoClient().test_database.test_collection.insert_many(
       [{'i': i} for i in range(2000)])
 
@@ -144,7 +146,7 @@ store a document in MongoDB, call :meth:`~AsyncIOMotorCollection.insert_one` in
   ...
   >>>
   >>> import asyncio
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_insert())
   result ObjectId('...')
 
@@ -166,7 +168,7 @@ Insert documents in large batches with :meth:`~AsyncIOMotorCollection.insert_man
   ...         [{'i': i} for i in range(2000)])
   ...     print('inserted %d docs' % (len(result.inserted_ids),))
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_insert())
   inserted 2000 docs
 
@@ -183,7 +185,7 @@ less than 1:
   ...     document = await db.test_collection.find_one({'i': {'$lt': 1}})
   ...     pprint.pprint(document)
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_find_one())
   {'_id': ObjectId('...'), 'i': 0}
 
@@ -211,7 +213,7 @@ To find all documents with "i" less than 5:
   ...     for document in await cursor.to_list(length=100):
   ...         pprint.pprint(document)
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_find())
   {'_id': ObjectId('...'), 'i': 0}
   {'_id': ObjectId('...'), 'i': 1}
@@ -234,7 +236,7 @@ You can handle one document at a time in an ``async for`` loop:
   ...     async for document in c.find({'i': {'$lt': 2}}):
   ...         pprint.pprint(document)
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_find())
   {'_id': ObjectId('...'), 'i': 0}
   {'_id': ObjectId('...'), 'i': 1}
@@ -250,7 +252,7 @@ You can apply a sort, limit, or skip to a query before you begin iterating:
   ...     async for document in cursor:
   ...         pprint.pprint(document)
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_find())
   {'_id': ObjectId('...'), 'i': 2}
   {'_id': ObjectId('...'), 'i': 1}
@@ -274,7 +276,7 @@ that match a query:
   ...     n = await db.test_collection.count_documents({'i': {'$gt': 1000}})
   ...     print('%s documents where i > 1000' % n)
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_count())
   2000 documents in collection
   999 documents where i > 1000
@@ -299,7 +301,7 @@ replacement document. The query follows the same syntax as for :meth:`find` or
   ...     new_document = await coll.find_one({'_id': _id})
   ...     print('document is now %s' % pprint.pformat(new_document))
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_replace())
   found document: {'_id': ObjectId('...'), 'i': 50}
   replaced 1 document
@@ -322,7 +324,7 @@ operator to set "key" to "value":
   ...     new_document = await coll.find_one({'i': 51})
   ...     print('document is now %s' % pprint.pformat(new_document))
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_update())
   updated 1 document
   document is now {'_id': ObjectId('...'), 'i': 51, 'key': 'value'}
@@ -353,7 +355,7 @@ Deleting Documents
   ...     result = await db.test_collection.delete_many({'i': {'$gte': 1000}})
   ...     print('%s documents after' % (await coll.count_documents({})))
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(do_delete_many())
   2000 documents before calling delete_many()
   1000 documents after
@@ -373,7 +375,7 @@ the :meth:`~motor.motor_asyncio.AsyncIOMotorDatabase.command` method on
   ...     response = await db.command(SON([("distinct", "test_collection"),
   ...                                      ("key", "i")]))
   ...
-  >>> loop = asyncio.get_event_loop()
+  >>> loop = client.get_io_loop()
   >>> loop.run_until_complete(use_distinct_command())
 
 Since the order of command parameters matters, don't use a Python dict to pass

motor/core.py

@@ -137,7 +137,8 @@ def __init__(self, *args, **kwargs):
             io_loop = kwargs.pop("io_loop")
             self._framework.check_event_loop(io_loop)
         else:
-            io_loop = self._framework.get_event_loop()
+            io_loop = None
+        self._io_loop = io_loop
 
         kwargs.setdefault("connect", False)
         kwargs.setdefault(
@@ -146,7 +147,12 @@ def __init__(self, *args, **kwargs):
 
         delegate = self.__delegate_class__(*args, **kwargs)
         super().__init__(delegate)
-        self.io_loop = io_loop
+
+    @property
+    def io_loop(self):
+        if self._io_loop is None:
+            self._io_loop = self._framework.get_event_loop()
+        return self._io_loop
 
     def get_io_loop(self):
         return self.io_loop
@@ -1069,22 +1075,13 @@ def main():
                       change_stream.close()
 
           # asyncio
-          from asyncio import get_event_loop
-
-          def main():
-              loop = get_event_loop()
-              task = loop.create_task(watch_collection)
-
-              try:
-                  loop.run_forever()
-              except KeyboardInterrupt:
+          try:
+              asyncio.run(watch_collection)
+          except KeyboardInterrupt:
                   pass
-              finally:
-                  if change_stream is not None:
-                      change_stream.close()
-
-                  # Prevent "Task was destroyed but it is pending!"
-                  loop.run_until_complete(task)
+          finally:
+              if change_stream is not None:
+                  change_stream.close()
 
         The :class:`~MotorChangeStream` async iterable blocks
         until the next change document is returned or an error is raised. If
@@ -1946,13 +1943,19 @@ def __init__(
         if io_loop:
             self._framework.check_event_loop(io_loop)
         else:
-            io_loop = self._framework.get_event_loop()
+            io_loop = None
         sync_client = key_vault_client.delegate
         delegate = self.__delegate_class__(
             kms_providers, key_vault_namespace, sync_client, codec_options
         )
         super().__init__(delegate)
-        self.io_loop = io_loop
+        self._io_loop = io_loop
+
+    @property
+    def io_loop(self):
+        if self._io_loop is None:
+            self._io_loop = self._framework.get_event_loop()
+        return self._io_loop
 
     def get_io_loop(self):
         return self.io_loop

motor/frameworks/asyncio/__init__.py

@@ -37,7 +37,11 @@
 
 
 def get_event_loop():
-    return asyncio.get_event_loop()
+    try:
+        return asyncio.get_running_loop()
+    except RuntimeError:
+        # Workaround for bugs.python.org/issue39529.
+        return asyncio.get_event_loop_policy().get_event_loop()
 
 
 def is_event_loop(loop):

setup.py

@@ -1,6 +1,12 @@
 import sys
-from distutils.cmd import Command
-from distutils.errors import DistutilsOptionError
+
+if sys.version_info[:2] < (3, 10):
+    from distutils.cmd import Command
+    from distutils.errors import DistutilsOptionError as OptionError
+else:
+    from setuptools import Command
+    from setuptools.errors import OptionError
+
 
 from setuptools import setup
 
@@ -69,7 +75,7 @@ def finalize_options(self):
         if self.test_suite is None and self.test_module is None:
             self.test_module = "test"
         elif self.test_module is not None and self.test_suite is not None:
-            raise DistutilsOptionError("You may specify a module or suite, but not both")
+            raise OptionError("You may specify a module or suite, but not both")
 
     def run(self):
         # Installing required packages, running egg_info and build_ext are

tox.ini

@@ -70,6 +70,8 @@ deps =
     synchro37: tornado>=6,<7
     synchro37: nose
 
+setenv =
+    PYTHONWARNINGS="error,ignore:The distutils package is deprecated:DeprecationWarning"
 commands =
     python --version
     python setup.py test --xunit-output=xunit-results {posargs}