Resolve

objectory.resolve

Provide a generic resolution utility for creating objects from an existing instance or an objectory configuration dictionary.

objectory.resolve.resolve_object

resolve_object(
    obj: T | dict[str, Any], cls: type[T] = object
) -> T

Resolve an instance of cls from an existing object or a configuration dictionary.

If obj is already an instance of cls it is returned as-is. If it is a :class:dict, it is treated as an objectory factory configuration and instantiated via :func:objectory.factory.

Note

Any :class:dict (including instances of dict subclasses, e.g. Counter or OrderedDict) is always treated as a factory configuration, even when it is already a valid instance of cls. Do not use this function to resolve objects whose expected type is itself a dict subclass.

Parameters:

Name	Type	Description	Default
obj	T | dict[str, Any]	Either a fully configured instance of cls, or a :class:dict containing an objectory factory specification (must include a "_target_" key pointing to the fully-qualified class name).	required
cls	type[T]	The expected type. Used to validate the resolved object, whether obj was already an instance or was built from a configuration dictionary. Defaults to :class:object, which accepts any resolved value without validation.	object

Returns:

Type	Description
T	A configured instance of cls.

Raises:

Type	Description
IncorrectTypeFactoryError	If obj is a :class:dict missing the "_target_" key, or if the resolved object is not an instance of cls.

Example

>>> from datetime import date
>>> from objectory import resolve_object
>>> # From an existing instance:
>>> d = resolve_object(date(2020, 1, 1), cls=date)
>>> # From a configuration dictionary:
>>> d = resolve_object(
...     {"_target_": "datetime.date", "year": 2020, "month": 1, "day": 1}, cls=date
... )