def _get_parents(cls: type, lizers: list) -> list:
"""
Return a list of serializers or deserializers that can handle a parent
of ``cls``.
:param cls: the type that
:param lizers: a list of serializers or deserializers.
:return: a list of serializers or deserializers.
"""
parents = []
naked_cls = get_naked_class(cls)
for cls_ in lizers:
try:
if issubclass(naked_cls, cls_):
parents.append(cls_)
except (TypeError, AttributeError):
pass # Some types do not support `issubclass` (e.g. Union).
return parents
def default_mapping_deserializer(obj: dict, cls: type, **kwargs) -> Mapping:
"""
Deserialize a (JSON) dict into a mapping by deserializing all items of that
dict.
:param obj: the dict that needs deserializing.
:param cls: the type, optionally with a generic (e.g. Set[str]).
:param kwargs: any keyword arguments.
:return: a deserialized set instance.
"""
cls_ = Mapping
if hasattr(cls, '__args__'):
cls_ = MappingType[cls.__args__]
dict_ = default_dict_deserializer(obj, cls_, **kwargs)
result = dict_
# Strip any generics from cls to allow for an instance check.
naked_cls = get_naked_class(cls)
if not isinstance(result, naked_cls):
result = cls(dict_)
return result
def default_iterable_deserializer(obj: list, cls: type, **kwargs) -> Iterable:
"""
Deserialize a (JSON) list into an ``Iterable`` by deserializing all items
of that list. The given obj is assumed to be homogeneous; if the list has a
generic type (e.g. Set[datetime]) then it is assumed that all elements can
be deserialized to that type.
:param obj: The list that needs deserializing to an ``Iterable``.
:param cls: The type, optionally with a generic (e.g. Deque[str]).
:param kwargs: Any keyword arguments.
:return: A deserialized ``Iterable`` (e.g. ``set``) instance.
"""
cls_ = Mapping
if hasattr(cls, '__args__'):
cls_ = IterableType[cls.__args__]
list_ = default_list_deserializer(obj, cls_, **kwargs)
result = list_
naked_cls = get_naked_class(cls)
if not isinstance(result, naked_cls):
result = naked_cls(list_)
return result
