# SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved. | |
# SPDX-License-Identifier: Apache-2.0 | |
# | |
# 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. | |
import pydoc | |
from typing import Any | |
""" | |
`locate` provide ways to map a string (typically found | |
in config files) to callable objects. | |
""" | |
__all__ = ["locate"] | |
def _convert_target_to_string(t: Any) -> str: | |
""" | |
Inverse of ``locate()``. | |
Args: | |
t: any object with ``__module__`` and ``__qualname__`` | |
""" | |
module, qualname = t.__module__, t.__qualname__ | |
# Compress the path to this object, e.g. ``module.submodule._impl.class`` | |
# may become ``module.submodule.class``, if the later also resolves to the same | |
# object. This simplifies the string, and also is less affected by moving the | |
# class implementation. | |
module_parts = module.split(".") | |
for k in range(1, len(module_parts)): | |
prefix = ".".join(module_parts[:k]) | |
candidate = f"{prefix}.{qualname}" | |
try: | |
if locate(candidate) is t: | |
return candidate | |
except ImportError: | |
pass | |
return f"{module}.{qualname}" | |
def locate(name: str) -> Any: | |
""" | |
Locate and return an object ``x`` using an input string ``{x.__module__}.{x.__qualname__}``, | |
such as "module.submodule.class_name". | |
Raise Exception if it cannot be found. | |
""" | |
obj = pydoc.locate(name) | |
# Some cases (e.g. torch.optim.sgd.SGD) not handled correctly | |
# by pydoc.locate. Try a private function from hydra. | |
if obj is None: | |
try: | |
# from hydra.utils import get_method - will print many errors | |
from hydra.utils import _locate | |
except ImportError as e: | |
raise ImportError(f"Cannot dynamically locate object {name}!") from e | |
else: | |
obj = _locate(name) # it raises if fails | |
return obj | |