mongo-python-driver/pymongo/_lazy_import.py
2024-03-25 12:55:41 -05:00

39 lines
1.3 KiB
Python

# Copyright 2024-present MongoDB, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you
# may not use this file except in compliance with the License. You
# may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied. See the License for the specific language governing
# permissions and limitations under the License.
from __future__ import annotations
import importlib.util
import sys
from types import ModuleType
def lazy_import(name: str) -> ModuleType:
"""Lazily import a module by name
From https://docs.python.org/3/library/importlib.html#implementing-lazy-imports
"""
try:
spec = importlib.util.find_spec(name)
except ValueError:
raise ModuleNotFoundError(name=name) from None
if spec is None:
raise ModuleNotFoundError(name=name)
assert spec is not None
loader = importlib.util.LazyLoader(spec.loader) # type:ignore[arg-type]
spec.loader = loader
module = importlib.util.module_from_spec(spec)
sys.modules[name] = module
loader.exec_module(module)
return module