Source code for ax.utils.common.serialization

#!/usr/bin/env python3
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.

import inspect
import pydoc
from types import FunctionType
from typing import Any, Callable, Dict, List, Optional, Type


# https://stackoverflow.com/a/39235373
[docs]def named_tuple_to_dict(data: Any) -> Any: """Recursively convert NamedTuples to dictionaries.""" if isinstance(data, dict): return {key: named_tuple_to_dict(value) for key, value in data.items()} elif isinstance(data, list): return [named_tuple_to_dict(value) for value in data] elif _is_named_tuple(data): return { key: named_tuple_to_dict(value) for key, value in data._asdict().items() } elif isinstance(data, tuple): return tuple(named_tuple_to_dict(value) for value in data) else: return data
# https://stackoverflow.com/a/2166841 def _is_named_tuple(x: Any) -> bool: """Return True if x is an instance of NamedTuple.""" t = type(x) b = t.__bases__ if len(b) != 1 or b[0] != tuple: return False f = getattr(t, "_fields", None) if not isinstance(f, tuple): return False # pragma nocover return all(type(n) == str for n in f)
[docs]def callable_to_reference(callable: Callable) -> str: """Obtains path to the callable of form <module>.<name>.""" if not isinstance(callable, (FunctionType, type)): raise TypeError(f"Expected to encode function or class, got: {callable}.") name = f"{callable.__module__}.{callable.__qualname__}" try: assert pydoc.locate(name) is callable return name except Exception as err: raise TypeError( f"Callable {callable.__qualname__} is not properly exposed in " f"{callable.__module__} (exception: {err})." )
[docs]def callable_from_reference(path: str) -> Callable: """Retrieves a callable by its path.""" return pydoc.locate(path) # pyre-ignore[7]
[docs]def serialize_init_args( object: Any, exclude_fields: Optional[List[str]] = None ) -> Dict[str, Any]: """Given an object, return a dictionary of the arguments that are needed by its constructor. """ properties = {} exclude_args = ["self", "args", "kwargs"] + (exclude_fields or []) signature = inspect.signature(object.__class__.__init__) for arg in signature.parameters: if arg in exclude_args: continue try: value = getattr(object, arg) except AttributeError: raise AttributeError( f"{object.__class__} is missing a value for {arg}, " f"which is needed by its constructor." ) properties[arg] = value return properties
[docs]def extract_init_args(args: Dict[str, Any], class_: Type) -> Dict[str, Any]: """Given a dictionary, extract the arguments required for the given class's constructor. """ init_args = {} signature = inspect.signature(class_.__init__) for arg, info in signature.parameters.items(): if arg in ["self", "args", "kwargs"]: continue value = args.get(arg) if value is None: # Only necessary to raise an exception if there is no default # value for this argument if info.default is inspect.Parameter.empty: raise ValueError( f"Cannot decode because required argument {arg} is missing." ) else: # Constructor will use default value continue # pragma: no cover init_args[arg] = value return init_args