Source code for detectron2.utils.registry

# Copyright (c) Facebook, Inc. and its affiliates.

from typing import Any
import pydoc
from fvcore.common.registry import Registry  # for backward compatibility.

``Registry`` and `locate` provide ways to map a string (typically found
in config files) to callable objects.

__all__ = ["Registry", "locate"]

def _convert_target_to_string(t: Any) -> str:
    Inverse of ``locate()``.

        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}"
            if locate(candidate) is t:
                return candidate
        except ImportError:
    return f"{module}.{qualname}"

[docs]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