from typing import Optional
from jivago.inject import typing_meta_helper
from jivago.lang.annotations import Override
from jivago.lang.stream import Stream
from jivago.serialization.deserialization_strategy import DeserializationStrategy, T
[docs]class OptionalAttributeDeserializationStrategy(DeserializationStrategy):
def __init__(self, deserializer: "Deserializer"):
self.deserializer = deserializer
[docs] @Override
def can_handle_deserialization(self, declared_type: type) -> bool:
return typing_meta_helper.is_optional_typing_meta(declared_type)
[docs] @Override
def deserialize(self, obj, declared_type: Optional[T]) -> Optional[T]:
if obj is None:
return obj
non_nil_declared_type = Stream(declared_type.__args__).firstMatch(lambda x: x != type(None))
return self.deserializer.deserialize(obj, non_nil_declared_type)