python lsp

server/libs/cattrs/preconf/orjson.py

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+"""Preconfigured converters for orjson."""
+
+from base64 import b85decode, b85encode
+from collections.abc import Set
+from datetime import date, datetime
+from enum import Enum
+from functools import partial
+from typing import Any, TypeVar, Union
+
+from orjson import dumps, loads
+
+from .._compat import is_subclass
+from ..cols import is_mapping, is_namedtuple, namedtuple_unstructure_factory
+from ..converters import 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__ = ["OrjsonConverter", "configure_converter", "make_converter"]
+
+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: Converter) -> None:
+    """
+    Configure the converter for use with the orjson library.
+
+    * bytes are serialized as base85 strings
+    * datetimes and dates are passed through to be serialized as RFC 3339 by orjson
+    * typed namedtuples are serialized as lists
+    * sets are serialized as lists
+    * string enum mapping keys have special handling
+    * mapping keys are coerced into strings when unstructuring
+    * bare, string and int enums are passed through when unstructuring
+
+    .. versionchanged:: 24.1.0
+        Add support for typed namedtuples.
+    .. 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_structure_hook(datetime, lambda v, _: datetime.fromisoformat(v))
+    converter.register_structure_hook(date, lambda v, _: date.fromisoformat(v))
+
+    def unstructure_mapping_factory(cl: Any, unstructure_to=None):
+        key_handler = str
+        args = getattr(cl, "__args__", None)
+        if args:
+            if is_subclass(args[0], str) and is_subclass(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.get_unstructure_hook(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, unstructure_mapping_factory, True),
+            (
+                is_namedtuple,
+                partial(namedtuple_unstructure_factory, unstructure_to=tuple),
+                "extended",
+            ),
+        ]
+    )
+    converter.register_unstructure_hook_func(
+        partial(is_primitive_enum, include_bare_enums=True), identity
+    )
+    converter.register_unstructure_hook_factory(
+        is_literal_containing_enums, literals_with_enums_unstructure_factory
+    )
+    configure_union_passthrough(Union[str, bool, int, float, None], converter)
+
+
+@wrap(OrjsonConverter)
+def make_converter(*args: Any, **kwargs: Any) -> OrjsonConverter:
+    kwargs["unstruct_collection_overrides"] = {
+        Set: list,
+        **kwargs.get("unstruct_collection_overrides", {}),
+    }
+    res = OrjsonConverter(*args, **kwargs)
+    configure_converter(res)
+
+    return res