| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290 |
- """Provide an enhanced dataclass that performs validation."""
- from __future__ import annotations as _annotations
- import dataclasses
- import sys
- import types
- from typing import TYPE_CHECKING, Any, Callable, Generic, NoReturn, TypeVar, overload
- from typing_extensions import Literal, TypeGuard, dataclass_transform
- from ._internal import _config, _decorators, _typing_extra
- from ._internal import _dataclasses as _pydantic_dataclasses
- from ._migration import getattr_migration
- from .config import ConfigDict
- from .fields import Field
- if TYPE_CHECKING:
- from ._internal._dataclasses import PydanticDataclass
- __all__ = 'dataclass', 'rebuild_dataclass'
- _T = TypeVar('_T')
- if sys.version_info >= (3, 10):
- @dataclass_transform(field_specifiers=(dataclasses.field, Field))
- @overload
- def dataclass(
- *,
- init: Literal[False] = False,
- repr: bool = True,
- eq: bool = True,
- order: bool = False,
- unsafe_hash: bool = False,
- frozen: bool = False,
- config: ConfigDict | type[object] | None = None,
- validate_on_init: bool | None = None,
- kw_only: bool = ...,
- slots: bool = ...,
- ) -> Callable[[type[_T]], type[PydanticDataclass]]: # type: ignore
- ...
- @dataclass_transform(field_specifiers=(dataclasses.field, Field))
- @overload
- def dataclass(
- _cls: type[_T], # type: ignore
- *,
- init: Literal[False] = False,
- repr: bool = True,
- eq: bool = True,
- order: bool = False,
- unsafe_hash: bool = False,
- frozen: bool = False,
- config: ConfigDict | type[object] | None = None,
- validate_on_init: bool | None = None,
- kw_only: bool = ...,
- slots: bool = ...,
- ) -> type[PydanticDataclass]:
- ...
- else:
- @dataclass_transform(field_specifiers=(dataclasses.field, Field))
- @overload
- def dataclass(
- *,
- init: Literal[False] = False,
- repr: bool = True,
- eq: bool = True,
- order: bool = False,
- unsafe_hash: bool = False,
- frozen: bool = False,
- config: ConfigDict | type[object] | None = None,
- validate_on_init: bool | None = None,
- ) -> Callable[[type[_T]], type[PydanticDataclass]]: # type: ignore
- ...
- @dataclass_transform(field_specifiers=(dataclasses.field, Field))
- @overload
- def dataclass(
- _cls: type[_T], # type: ignore
- *,
- init: Literal[False] = False,
- repr: bool = True,
- eq: bool = True,
- order: bool = False,
- unsafe_hash: bool = False,
- frozen: bool = False,
- config: ConfigDict | type[object] | None = None,
- validate_on_init: bool | None = None,
- ) -> type[PydanticDataclass]:
- ...
- @dataclass_transform(field_specifiers=(dataclasses.field, Field))
- def dataclass(
- _cls: type[_T] | None = None,
- *,
- init: Literal[False] = False,
- repr: bool = True,
- eq: bool = True,
- order: bool = False,
- unsafe_hash: bool = False,
- frozen: bool = False,
- config: ConfigDict | type[object] | None = None,
- validate_on_init: bool | None = None,
- kw_only: bool = False,
- slots: bool = False,
- ) -> Callable[[type[_T]], type[PydanticDataclass]] | type[PydanticDataclass]:
- """Usage docs: https://docs.pydantic.dev/2.4/concepts/dataclasses/
- A decorator used to create a Pydantic-enhanced dataclass, similar to the standard Python `dataclass`,
- but with added validation.
- This function should be used similarly to `dataclasses.dataclass`.
- Args:
- _cls: The target `dataclass`.
- init: Included for signature compatibility with `dataclasses.dataclass`, and is passed through to
- `dataclasses.dataclass` when appropriate. If specified, must be set to `False`, as pydantic inserts its
- own `__init__` function.
- repr: A boolean indicating whether or not to include the field in the `__repr__` output.
- eq: Determines if a `__eq__` should be generated for the class.
- order: Determines if comparison magic methods should be generated, such as `__lt__`, but not `__eq__`.
- unsafe_hash: Determines if an unsafe hashing function should be included in the class.
- frozen: Determines if the generated class should be a 'frozen' `dataclass`, which does not allow its
- attributes to be modified from its constructor.
- config: A configuration for the `dataclass` generation.
- validate_on_init: A deprecated parameter included for backwards compatibility; in V2, all Pydantic dataclasses
- are validated on init.
- kw_only: Determines if `__init__` method parameters must be specified by keyword only. Defaults to `False`.
- slots: Determines if the generated class should be a 'slots' `dataclass`, which does not allow the addition of
- new attributes after instantiation.
- Returns:
- A decorator that accepts a class as its argument and returns a Pydantic `dataclass`.
- Raises:
- AssertionError: Raised if `init` is not `False` or `validate_on_init` is `False`.
- """
- assert init is False, 'pydantic.dataclasses.dataclass only supports init=False'
- assert validate_on_init is not False, 'validate_on_init=False is no longer supported'
- if sys.version_info >= (3, 10):
- kwargs = dict(kw_only=kw_only, slots=slots)
- else:
- kwargs = {}
- def create_dataclass(cls: type[Any]) -> type[PydanticDataclass]:
- """Create a Pydantic dataclass from a regular dataclass.
- Args:
- cls: The class to create the Pydantic dataclass from.
- Returns:
- A Pydantic dataclass.
- """
- original_cls = cls
- config_dict = config
- if config_dict is None:
- # if not explicitly provided, read from the type
- cls_config = getattr(cls, '__pydantic_config__', None)
- if cls_config is not None:
- config_dict = cls_config
- config_wrapper = _config.ConfigWrapper(config_dict)
- decorators = _decorators.DecoratorInfos.build(cls)
- # Keep track of the original __doc__ so that we can restore it after applying the dataclasses decorator
- # Otherwise, classes with no __doc__ will have their signature added into the JSON schema description,
- # since dataclasses.dataclass will set this as the __doc__
- original_doc = cls.__doc__
- if _pydantic_dataclasses.is_builtin_dataclass(cls):
- # Don't preserve the docstring for vanilla dataclasses, as it may include the signature
- # This matches v1 behavior, and there was an explicit test for it
- original_doc = None
- # We don't want to add validation to the existing std lib dataclass, so we will subclass it
- # If the class is generic, we need to make sure the subclass also inherits from Generic
- # with all the same parameters.
- bases = (cls,)
- if issubclass(cls, Generic):
- generic_base = Generic[cls.__parameters__] # type: ignore
- bases = bases + (generic_base,)
- cls = types.new_class(cls.__name__, bases)
- cls = dataclasses.dataclass( # type: ignore[call-overload]
- cls,
- # the value of init here doesn't affect anything except that it makes it easier to generate a signature
- init=True,
- repr=repr,
- eq=eq,
- order=order,
- unsafe_hash=unsafe_hash,
- frozen=frozen,
- **kwargs,
- )
- cls.__pydantic_decorators__ = decorators # type: ignore
- cls.__doc__ = original_doc
- cls.__module__ = original_cls.__module__
- cls.__qualname__ = original_cls.__qualname__
- pydantic_complete = _pydantic_dataclasses.complete_dataclass(
- cls, config_wrapper, raise_errors=False, types_namespace=None
- )
- cls.__pydantic_complete__ = pydantic_complete # type: ignore
- return cls
- if _cls is None:
- return create_dataclass
- return create_dataclass(_cls)
- __getattr__ = getattr_migration(__name__)
- if (3, 8) <= sys.version_info < (3, 11):
- # Monkeypatch dataclasses.InitVar so that typing doesn't error if it occurs as a type when evaluating type hints
- # Starting in 3.11, typing.get_type_hints will not raise an error if the retrieved type hints are not callable.
- def _call_initvar(*args: Any, **kwargs: Any) -> NoReturn:
- """This function does nothing but raise an error that is as similar as possible to what you'd get
- if you were to try calling `InitVar[int]()` without this monkeypatch. The whole purpose is just
- to ensure typing._type_check does not error if the type hint evaluates to `InitVar[<parameter>]`.
- """
- raise TypeError("'InitVar' object is not callable")
- dataclasses.InitVar.__call__ = _call_initvar
- def rebuild_dataclass(
- cls: type[PydanticDataclass],
- *,
- force: bool = False,
- raise_errors: bool = True,
- _parent_namespace_depth: int = 2,
- _types_namespace: dict[str, Any] | None = None,
- ) -> bool | None:
- """Try to rebuild the pydantic-core schema for the dataclass.
- This may be necessary when one of the annotations is a ForwardRef which could not be resolved during
- the initial attempt to build the schema, and automatic rebuilding fails.
- This is analogous to `BaseModel.model_rebuild`.
- Args:
- cls: The class to build the dataclass core schema for.
- force: Whether to force the rebuilding of the model schema, defaults to `False`.
- raise_errors: Whether to raise errors, defaults to `True`.
- _parent_namespace_depth: The depth level of the parent namespace, defaults to 2.
- _types_namespace: The types namespace, defaults to `None`.
- Returns:
- Returns `None` if the schema is already "complete" and rebuilding was not required.
- If rebuilding _was_ required, returns `True` if rebuilding was successful, otherwise `False`.
- """
- if not force and cls.__pydantic_complete__:
- return None
- else:
- if _types_namespace is not None:
- types_namespace: dict[str, Any] | None = _types_namespace.copy()
- else:
- if _parent_namespace_depth > 0:
- frame_parent_ns = _typing_extra.parent_frame_namespace(parent_depth=_parent_namespace_depth) or {}
- # Note: we may need to add something similar to cls.__pydantic_parent_namespace__ from BaseModel
- # here when implementing handling of recursive generics. See BaseModel.model_rebuild for reference.
- types_namespace = frame_parent_ns
- else:
- types_namespace = {}
- types_namespace = _typing_extra.get_cls_types_namespace(cls, types_namespace)
- return _pydantic_dataclasses.complete_dataclass(
- cls,
- _config.ConfigWrapper(cls.__pydantic_config__, check=False),
- raise_errors=raise_errors,
- types_namespace=types_namespace,
- )
- def is_pydantic_dataclass(__cls: type[Any]) -> TypeGuard[type[PydanticDataclass]]:
- """Whether a class is a pydantic dataclass.
- Args:
- __cls: The class.
- Returns:
- `True` if the class is a pydantic dataclass, `False` otherwise.
- """
- return dataclasses.is_dataclass(__cls) and '__pydantic_validator__' in __cls.__dict__
|