python lsp

server/libs/cattrs/preconf/json.py

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+"""Preconfigured converters for the stdlib json."""
+
+from base64 import b85decode, b85encode
+from collections.abc import Set
+from datetime import date, datetime
+from json import dumps, loads
+from typing import Any, TypeVar, Union
+
+from .._compat import Counter
+from ..converters import BaseConverter, Converter
+from ..fns import identity
+from ..literals import is_literal_containing_enums
+from ..strategies import configure_union_passthrough
+from . import is_primitive_enum, literals_with_enums_unstructure_factory, wrap
+
+__all__ = ["JsonConverter", "configure_converter", "make_converter"]
+
+T = TypeVar("T")
+
+
+class JsonConverter(Converter):
+    def dumps(self, obj: Any, unstructure_as: Any = None, **kwargs: Any) -> str:
+        return dumps(self.unstructure(obj, unstructure_as=unstructure_as), **kwargs)
+
+    def loads(self, data: Union[bytes, str], cl: type[T], **kwargs: Any) -> T:
+        return self.structure(loads(data, **kwargs), cl)
+
+
+def configure_converter(converter: BaseConverter) -> None:
+    """
+    Configure the converter for use with the stdlib json module.
+
+    * bytes are serialized as base85 strings
+    * datetimes are serialized as ISO 8601
+    * counters are serialized as dicts
+    * sets are serialized as lists
+    * string and int enums are passed through when unstructuring
+    * union passthrough is configured for unions of strings, bools, ints,
+      floats and None
+
+    .. versionchanged:: 24.2.0
+        Enums are left to the library to unstructure, speeding them up.
+    """
+    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))
+    converter.register_unstructure_hook_factory(
+        is_literal_containing_enums, literals_with_enums_unstructure_factory
+    )
+    converter.register_unstructure_hook_func(is_primitive_enum, identity)
+    configure_union_passthrough(Union[str, bool, int, float, None], converter)
+
+
+@wrap(JsonConverter)
+def make_converter(*args: Any, **kwargs: Any) -> JsonConverter:
+    kwargs["unstruct_collection_overrides"] = {
+        Set: list,
+        Counter: dict,
+        **kwargs.get("unstruct_collection_overrides", {}),
+    }
+    res = JsonConverter(*args, **kwargs)
+    configure_converter(res)
+
+    return res