| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116 |
- # This file is dual licensed under the terms of the Apache License, Version
- # 2.0, and the BSD License. See the LICENSE file in the root of this repository
- # for complete details.
- from __future__ import annotations
- import dataclasses
- import sys
- import typing
- if sys.version_info < (3, 11):
- import typing_extensions
- # We use the `include_extras` parameter of `get_type_hints`, which was
- # added in Python 3.9. This can be replaced by the `typing` version
- # once the min version is >= 3.9
- if sys.version_info < (3, 9):
- get_type_hints = typing_extensions.get_type_hints
- else:
- get_type_hints = typing.get_type_hints
- else:
- get_type_hints = typing.get_type_hints
- from cryptography.hazmat.bindings._rust import declarative_asn1
- T = typing.TypeVar("T", covariant=True)
- U = typing.TypeVar("U")
- encode_der = declarative_asn1.encode_der
- def _normalize_field_type(
- field_type: typing.Any, field_name: str
- ) -> declarative_asn1.AnnotatedType:
- annotation = declarative_asn1.Annotation()
- if hasattr(field_type, "__asn1_root__"):
- annotated_root = field_type.__asn1_root__
- if not isinstance(annotated_root, declarative_asn1.AnnotatedType):
- raise TypeError(f"unsupported root type: {annotated_root}")
- return annotated_root
- else:
- rust_field_type = declarative_asn1.non_root_python_to_rust(field_type)
- return declarative_asn1.AnnotatedType(rust_field_type, annotation)
- def _annotate_fields(
- raw_fields: dict[str, type],
- ) -> dict[str, declarative_asn1.AnnotatedType]:
- fields = {}
- for field_name, field_type in raw_fields.items():
- # Recursively normalize the field type into something that the
- # Rust code can understand.
- annotated_field_type = _normalize_field_type(field_type, field_name)
- fields[field_name] = annotated_field_type
- return fields
- def _register_asn1_sequence(cls: type[U]) -> None:
- raw_fields = get_type_hints(cls, include_extras=True)
- root = declarative_asn1.AnnotatedType(
- declarative_asn1.Type.Sequence(cls, _annotate_fields(raw_fields)),
- declarative_asn1.Annotation(),
- )
- setattr(cls, "__asn1_root__", root)
- # Due to https://github.com/python/mypy/issues/19731, we can't define an alias
- # for `dataclass_transform` that conditionally points to `typing` or
- # `typing_extensions` depending on the Python version (like we do for
- # `get_type_hints`).
- # We work around it by making the whole decorated class conditional on the
- # Python version.
- if sys.version_info < (3, 11):
- @typing_extensions.dataclass_transform(kw_only_default=True)
- def sequence(cls: type[U]) -> type[U]:
- # We use `dataclasses.dataclass` to add an __init__ method
- # to the class with keyword-only parameters.
- if sys.version_info >= (3, 10):
- dataclass_cls = dataclasses.dataclass(
- repr=False,
- eq=False,
- # `match_args` was added in Python 3.10 and defaults
- # to True
- match_args=False,
- # `kw_only` was added in Python 3.10 and defaults to
- # False
- kw_only=True,
- )(cls)
- else:
- dataclass_cls = dataclasses.dataclass(
- repr=False,
- eq=False,
- )(cls)
- _register_asn1_sequence(dataclass_cls)
- return dataclass_cls
- else:
- @typing.dataclass_transform(kw_only_default=True)
- def sequence(cls: type[U]) -> type[U]:
- # Only add an __init__ method, with keyword-only
- # parameters.
- dataclass_cls = dataclasses.dataclass(
- repr=False,
- eq=False,
- match_args=False,
- kw_only=True,
- )(cls)
- _register_asn1_sequence(dataclass_cls)
- return dataclass_cls
|