83 lines
2.8 KiB
Python
83 lines
2.8 KiB
Python
"""Preconfigured converters for orjson."""
|
|
from base64 import b85decode, b85encode
|
|
from datetime import date, datetime
|
|
from enum import Enum
|
|
from typing import Any, Type, TypeVar, Union
|
|
|
|
from orjson import dumps, loads
|
|
|
|
from cattrs._compat import AbstractSet, is_mapping
|
|
|
|
from ..converters import BaseConverter, Converter
|
|
from ..fns import identity
|
|
from ..strategies import configure_union_passthrough
|
|
|
|
T = TypeVar("T")
|
|
|
|
|
|
class OrjsonConverter(Converter):
|
|
def dumps(self, obj: Any, unstructure_as: Any = None, **kwargs: Any) -> bytes:
|
|
return dumps(self.unstructure(obj, unstructure_as=unstructure_as), **kwargs)
|
|
|
|
def loads(self, data: Union[bytes, bytearray, memoryview, str], cl: Type[T]) -> T:
|
|
return self.structure(loads(data), cl)
|
|
|
|
|
|
def configure_converter(converter: BaseConverter):
|
|
"""
|
|
Configure the converter for use with the orjson library.
|
|
|
|
* bytes are serialized as base85 strings
|
|
* datetimes are serialized as ISO 8601
|
|
* sets are serialized as lists
|
|
* string enum mapping keys have special handling
|
|
* mapping keys are coerced into strings when unstructuring
|
|
"""
|
|
converter.register_unstructure_hook(
|
|
bytes, lambda v: (b85encode(v) if v else b"").decode("utf8")
|
|
)
|
|
converter.register_structure_hook(bytes, lambda v, _: b85decode(v))
|
|
|
|
converter.register_unstructure_hook(datetime, lambda v: v.isoformat())
|
|
converter.register_structure_hook(datetime, lambda v, _: datetime.fromisoformat(v))
|
|
converter.register_unstructure_hook(date, lambda v: v.isoformat())
|
|
converter.register_structure_hook(date, lambda v, _: date.fromisoformat(v))
|
|
|
|
def gen_unstructure_mapping(cl: Any, unstructure_to=None):
|
|
key_handler = str
|
|
args = getattr(cl, "__args__", None)
|
|
if args:
|
|
if issubclass(args[0], str) and issubclass(args[0], Enum):
|
|
|
|
def key_handler(v):
|
|
return v.value
|
|
|
|
else:
|
|
# It's possible the handler for the key type has been overridden.
|
|
# (For example base85 encoding for bytes.)
|
|
# In that case, we want to use the override.
|
|
|
|
kh = converter._unstructure_func.dispatch(args[0])
|
|
if kh != identity:
|
|
key_handler = kh
|
|
|
|
return converter.gen_unstructure_mapping(
|
|
cl, unstructure_to=unstructure_to, key_handler=key_handler
|
|
)
|
|
|
|
converter._unstructure_func.register_func_list(
|
|
[(is_mapping, gen_unstructure_mapping, True)]
|
|
)
|
|
configure_union_passthrough(Union[str, bool, int, float, None], converter)
|
|
|
|
|
|
def make_converter(*args: Any, **kwargs: Any) -> OrjsonConverter:
|
|
kwargs["unstruct_collection_overrides"] = {
|
|
AbstractSet: list,
|
|
**kwargs.get("unstruct_collection_overrides", {}),
|
|
}
|
|
res = OrjsonConverter(*args, **kwargs)
|
|
configure_converter(res)
|
|
|
|
return res
|