default_union_deserializer()   A
last analyzed

Complexity

Conditions 4

Size

Total Lines 22
Code Lines 11

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
eloc 11
dl 0
loc 22
rs 9.85
c 0
b 0
f 0
cc 4
nop 3
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from typing import Union
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from jsons._common_impl import get_class_name
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from jsons._compatibility_impl import get_union_params
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from jsons._load_impl import load
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from jsons.exceptions import JsonsError, DeserializationError
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def default_union_deserializer(obj: object, cls: Union, **kwargs) -> object:
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    """
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    Deserialize an object to any matching type of the given union. The first
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    successful deserialization is returned.
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    :param obj: The object that needs deserializing.
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    :param cls: The Union type with a generic (e.g. Union[str, int]).
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    :param kwargs: Any keyword arguments that are passed through the
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    deserialization process.
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    :return: An object of the first type of the Union that could be
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    deserialized successfully.
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    """
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    for sub_type in get_union_params(cls):
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        try:
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            return load(obj, sub_type, **kwargs)
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        except JsonsError:
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            pass  # Try the next one.
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    else:
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        args_msg = ', '.join([get_class_name(cls_)
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                              for cls_ in get_union_params(cls)])
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        err_msg = ('Could not match the object of type "{}" to any type of '
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                   'the Union: {}'.format(type(obj).__name__, args_msg))
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        raise DeserializationError(err_msg, obj, cls)
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