codekingpro/portable-devtools
114k
1"""Provide an enhanced dataclass that performs validation."""2 3from __future__ import annotations as _annotations4 5import dataclasses6import functools7import sys8import types9from typing import TYPE_CHECKING, Any, Callable, Generic, Literal, NoReturn, TypeVar, overload10from warnings import warn11 12from typing_extensions import TypeGuard, dataclass_transform13 14from ._internal import _config, _decorators, _mock_val_ser, _namespace_utils, _typing_extra15from ._internal import _dataclasses as _pydantic_dataclasses16from ._migration import getattr_migration17from .config import ConfigDict18from .errors import PydanticUserError19from .fields import Field, FieldInfo, PrivateAttr20 21if TYPE_CHECKING:22 from ._internal._dataclasses import PydanticDataclass23 from ._internal._namespace_utils import MappingNamespace24 25__all__ = 'dataclass', 'rebuild_dataclass'26 27_T = TypeVar('_T')28 29if sys.version_info >= (3, 10):30 31 @dataclass_transform(field_specifiers=(dataclasses.field, Field, PrivateAttr))32 @overload33 def dataclass(34 *,35 init: Literal[False] = False,36 repr: bool = True,37 eq: bool = True,38 order: bool = False,39 unsafe_hash: bool = False,40 frozen: bool = False,41 config: ConfigDict | type[object] | None = None,42 validate_on_init: bool | None = None,43 kw_only: bool = ...,44 slots: bool = ...,45 ) -> Callable[[type[_T]], type[PydanticDataclass]]: # type: ignore46 ...47 48 @dataclass_transform(field_specifiers=(dataclasses.field, Field, PrivateAttr))49 @overload50 def dataclass(51 _cls: type[_T], # type: ignore52 *,53 init: Literal[False] = False,54 repr: bool = True,55 eq: bool = True,56 order: bool = False,57 unsafe_hash: bool = False,58 frozen: bool | None = None,59 config: ConfigDict | type[object] | None = None,60 validate_on_init: bool | None = None,61 kw_only: bool = ...,62 slots: bool = ...,63 ) -> type[PydanticDataclass]: ...64 65else:66 67 @dataclass_transform(field_specifiers=(dataclasses.field, Field, PrivateAttr))68 @overload69 def dataclass(70 *,71 init: Literal[False] = False,72 repr: bool = True,73 eq: bool = True,74 order: bool = False,75 unsafe_hash: bool = False,76 frozen: bool | None = None,77 config: ConfigDict | type[object] | None = None,78 validate_on_init: bool | None = None,79 ) -> Callable[[type[_T]], type[PydanticDataclass]]: # type: ignore80 ...81 82 @dataclass_transform(field_specifiers=(dataclasses.field, Field, PrivateAttr))83 @overload84 def dataclass(85 _cls: type[_T], # type: ignore86 *,87 init: Literal[False] = False,88 repr: bool = True,89 eq: bool = True,90 order: bool = False,91 unsafe_hash: bool = False,92 frozen: bool | None = None,93 config: ConfigDict | type[object] | None = None,94 validate_on_init: bool | None = None,95 ) -> type[PydanticDataclass]: ...96 97 98@dataclass_transform(field_specifiers=(dataclasses.field, Field, PrivateAttr))99def dataclass(100 _cls: type[_T] | None = None,101 *,102 init: Literal[False] = False,103 repr: bool = True,104 eq: bool = True,105 order: bool = False,106 unsafe_hash: bool = False,107 frozen: bool | None = None,108 config: ConfigDict | type[object] | None = None,109 validate_on_init: bool | None = None,110 kw_only: bool = False,111 slots: bool = False,112) -> Callable[[type[_T]], type[PydanticDataclass]] | type[PydanticDataclass]:113 """!!! abstract "Usage Documentation"114 [`dataclasses`](../concepts/dataclasses.md)115 116 A decorator used to create a Pydantic-enhanced dataclass, similar to the standard Python `dataclass`,117 but with added validation.118 119 This function should be used similarly to `dataclasses.dataclass`.120 121 Args:122 _cls: The target `dataclass`.123 init: Included for signature compatibility with `dataclasses.dataclass`, and is passed through to124 `dataclasses.dataclass` when appropriate. If specified, must be set to `False`, as pydantic inserts its125 own `__init__` function.126 repr: A boolean indicating whether to include the field in the `__repr__` output.127 eq: Determines if a `__eq__` method should be generated for the class.128 order: Determines if comparison magic methods should be generated, such as `__lt__`, but not `__eq__`.129 unsafe_hash: Determines if a `__hash__` method should be included in the class, as in `dataclasses.dataclass`.130 frozen: Determines if the generated class should be a 'frozen' `dataclass`, which does not allow its131 attributes to be modified after it has been initialized. If not set, the value from the provided `config` argument will be used (and will default to `False` otherwise).132 config: The Pydantic config to use for the `dataclass`.133 validate_on_init: A deprecated parameter included for backwards compatibility; in V2, all Pydantic dataclasses134 are validated on init.135 kw_only: Determines if `__init__` method parameters must be specified by keyword only. Defaults to `False`.136 slots: Determines if the generated class should be a 'slots' `dataclass`, which does not allow the addition of137 new attributes after instantiation.138 139 Returns:140 A decorator that accepts a class as its argument and returns a Pydantic `dataclass`.141 142 Raises:143 AssertionError: Raised if `init` is not `False` or `validate_on_init` is `False`.144 """145 assert init is False, 'pydantic.dataclasses.dataclass only supports init=False'146 assert validate_on_init is not False, 'validate_on_init=False is no longer supported'147 148 if sys.version_info >= (3, 10):149 kwargs = {'kw_only': kw_only, 'slots': slots}150 else:151 kwargs = {}152 153 def create_dataclass(cls: type[Any]) -> type[PydanticDataclass]:154 """Create a Pydantic dataclass from a regular dataclass.155 156 Args:157 cls: The class to create the Pydantic dataclass from.158 159 Returns:160 A Pydantic dataclass.161 """162 from ._internal._utils import is_model_class163 164 if is_model_class(cls):165 raise PydanticUserError(166 f'Cannot create a Pydantic dataclass from {cls.__name__} as it is already a Pydantic model',167 code='dataclass-on-model',168 )169 170 original_cls = cls171 172 # we warn on conflicting config specifications, but only if the class doesn't have a dataclass base173 # because a dataclass base might provide a __pydantic_config__ attribute that we don't want to warn about174 has_dataclass_base = any(dataclasses.is_dataclass(base) for base in cls.__bases__)175 if not has_dataclass_base and config is not None and hasattr(cls, '__pydantic_config__'):176 warn(177 f'`config` is set via both the `dataclass` decorator and `__pydantic_config__` for dataclass {cls.__name__}. '178 f'The `config` specification from `dataclass` decorator will take priority.',179 category=UserWarning,180 stacklevel=2,181 )182 183 # if config is not explicitly provided, try to read it from the type184 config_dict = config if config is not None else getattr(cls, '__pydantic_config__', None)185 config_wrapper = _config.ConfigWrapper(config_dict)186 decorators = _decorators.DecoratorInfos.build(cls, replace_wrapped_methods=True)187 decorators.update_from_config(config_wrapper)188 189 # Keep track of the original __doc__ so that we can restore it after applying the dataclasses decorator190 # Otherwise, classes with no __doc__ will have their signature added into the JSON schema description,191 # since dataclasses.dataclass will set this as the __doc__192 original_doc = cls.__doc__193 194 if _pydantic_dataclasses.is_stdlib_dataclass(cls):195 # Vanilla dataclasses include a default docstring (representing the class signature),196 # which we don't want to preserve.197 original_doc = None198 199 # We don't want to add validation to the existing std lib dataclass, so we will subclass it200 # If the class is generic, we need to make sure the subclass also inherits from Generic201 # with all the same parameters.202 bases = (cls,)203 if issubclass(cls, Generic):204 generic_base = Generic[cls.__parameters__] # type: ignore205 bases = bases + (generic_base,)206 cls = types.new_class(cls.__name__, bases)207 208 # Respect frozen setting from dataclass constructor and fallback to config setting if not provided209 if frozen is not None:210 frozen_ = frozen211 if config_wrapper.frozen:212 # It's not recommended to define both, as the setting from the dataclass decorator will take priority.213 warn(214 f'`frozen` is set via both the `dataclass` decorator and `config` for dataclass {cls.__name__!r}.'215 'This is not recommended. The `frozen` specification on `dataclass` will take priority.',216 category=UserWarning,217 stacklevel=2,218 )219 else:220 frozen_ = config_wrapper.frozen or False221 222 # Make Pydantic's `Field()` function compatible with stdlib dataclasses. As we'll decorate223 # `cls` with the stdlib `@dataclass` decorator first, there are two attributes, `kw_only` and224 # `repr` that need to be understood *during* the stdlib creation. We do so in two steps:225 226 # 1. On the decorated class, wrap `Field()` assignment with `dataclass.field()`, with the227 # two attributes set (done in `as_dataclass_field()`)228 cls_anns = _typing_extra.safe_get_annotations(cls)229 for field_name in cls_anns:230 # We should look for assignments in `__dict__` instead, but for now we follow231 # the same behavior as stdlib dataclasses (see https://github.com/python/cpython/issues/88609)232 field_value = getattr(cls, field_name, None)233 if isinstance(field_value, FieldInfo):234 setattr(cls, field_name, _pydantic_dataclasses.as_dataclass_field(field_value))235 236 # 2. For bases of `cls` that are stdlib dataclasses, we temporarily patch their fields237 # (see the docstring of the context manager):238 with _pydantic_dataclasses.patch_base_fields(cls):239 cls = dataclasses.dataclass( # pyright: ignore[reportCallIssue]240 cls,241 # the value of init here doesn't affect anything except that it makes it easier to generate a signature242 init=True,243 repr=repr,244 eq=eq,245 order=order,246 unsafe_hash=unsafe_hash,247 frozen=frozen_,248 **kwargs,249 )250 251 if config_wrapper.validate_assignment:252 original_setattr = cls.__setattr__253 254 @functools.wraps(cls.__setattr__)255 def validated_setattr(instance: PydanticDataclass, name: str, value: Any, /) -> None:256 if frozen_:257 return original_setattr(instance, name, value) # pyright: ignore[reportCallIssue]258 inst_cls = type(instance)259 attr = getattr(inst_cls, name, None)260 261 if isinstance(attr, property):262 attr.__set__(instance, value)263 elif isinstance(attr, functools.cached_property):264 instance.__dict__.__setitem__(name, value)265 else:266 inst_cls.__pydantic_validator__.validate_assignment(instance, name, value)267 268 cls.__setattr__ = validated_setattr.__get__(None, cls) # type: ignore269 270 if slots and not hasattr(cls, '__setstate__'):271 # If slots is set, `pickle` (relied on by `copy.copy()`) will use272 # `__setattr__()` to reconstruct the dataclass. However, the custom273 # `__setattr__()` set above relies on `validate_assignment()`, which274 # in turn expects all the field values to be already present on the275 # instance, resulting in attribute errors.276 # As such, we make use of `object.__setattr__()` instead.277 # Note that we do so only if `__setstate__()` isn't already set (this is the278 # case if on top of `slots`, `frozen` is used).279 280 # Taken from `dataclasses._dataclass_get/setstate()`:281 def _dataclass_getstate(self: Any) -> list[Any]:282 return [getattr(self, f.name) for f in dataclasses.fields(self)]283 284 def _dataclass_setstate(self: Any, state: list[Any]) -> None:285 for field, value in zip(dataclasses.fields(self), state):286 object.__setattr__(self, field.name, value)287 288 cls.__getstate__ = _dataclass_getstate # pyright: ignore[reportAttributeAccessIssue]289 cls.__setstate__ = _dataclass_setstate # pyright: ignore[reportAttributeAccessIssue]290 291 # This is an undocumented attribute to distinguish stdlib/Pydantic dataclasses.292 # It should be set as early as possible:293 cls.__is_pydantic_dataclass__ = True294 cls.__pydantic_decorators__ = decorators # type: ignore295 cls.__doc__ = original_doc296 # Can be non-existent for dynamically created classes:297 firstlineno = getattr(original_cls, '__firstlineno__', None)298 cls.__module__ = original_cls.__module__299 if sys.version_info >= (3, 13) and firstlineno is not None:300 # As per https://docs.python.org/3/reference/datamodel.html#type.__firstlineno__:301 # Setting the `__module__` attribute removes the `__firstlineno__` item from the type’s dictionary.302 original_cls.__firstlineno__ = firstlineno303 cls.__firstlineno__ = firstlineno304 cls.__qualname__ = original_cls.__qualname__305 cls.__pydantic_fields_complete__ = classmethod(_pydantic_fields_complete)306 cls.__pydantic_complete__ = False # `complete_dataclass` will set it to `True` if successful.307 # TODO `parent_namespace` is currently None, but we could do the same thing as Pydantic models:308 # fetch the parent ns using `parent_frame_namespace` (if the dataclass was defined in a function),309 # and possibly cache it (see the `__pydantic_parent_namespace__` logic for models).310 _pydantic_dataclasses.complete_dataclass(cls, config_wrapper, raise_errors=False)311 return cls312 313 return create_dataclass if _cls is None else create_dataclass(_cls)314 315 316def _pydantic_fields_complete(cls: type[PydanticDataclass]) -> bool:317 """Return whether the fields were successfully collected (i.e. type hints were successfully resolved).318 319 This is a private helper, not meant to be used outside Pydantic.320 """321 return all(field_info._complete for field_info in cls.__pydantic_fields__.values())322 323 324__getattr__ = getattr_migration(__name__)325 326if sys.version_info < (3, 11):327 # Monkeypatch dataclasses.InitVar so that typing doesn't error if it occurs as a type when evaluating type hints328 # Starting in 3.11, typing.get_type_hints will not raise an error if the retrieved type hints are not callable.329 330 def _call_initvar(*args: Any, **kwargs: Any) -> NoReturn:331 """This function does nothing but raise an error that is as similar as possible to what you'd get332 if you were to try calling `InitVar[int]()` without this monkeypatch. The whole purpose is just333 to ensure typing._type_check does not error if the type hint evaluates to `InitVar[<parameter>]`.334 """335 raise TypeError("'InitVar' object is not callable")336 337 dataclasses.InitVar.__call__ = _call_initvar338 339 340def rebuild_dataclass(341 cls: type[PydanticDataclass],342 *,343 force: bool = False,344 raise_errors: bool = True,345 _parent_namespace_depth: int = 2,346 _types_namespace: MappingNamespace | None = None,347) -> bool | None:348 """Try to rebuild the pydantic-core schema for the dataclass.349 350 This may be necessary when one of the annotations is a ForwardRef which could not be resolved during351 the initial attempt to build the schema, and automatic rebuilding fails.352 353 This is analogous to `BaseModel.model_rebuild`.354 355 Args:356 cls: The class to rebuild the pydantic-core schema for.357 force: Whether to force the rebuilding of the schema, defaults to `False`.358 raise_errors: Whether to raise errors, defaults to `True`.359 _parent_namespace_depth: The depth level of the parent namespace, defaults to 2.360 _types_namespace: The types namespace, defaults to `None`.361 362 Returns:363 Returns `None` if the schema is already "complete" and rebuilding was not required.364 If rebuilding _was_ required, returns `True` if rebuilding was successful, otherwise `False`.365 """366 if not force and cls.__pydantic_complete__:367 return None368 369 for attr in ('__pydantic_core_schema__', '__pydantic_validator__', '__pydantic_serializer__'):370 if attr in cls.__dict__ and not isinstance(getattr(cls, attr), _mock_val_ser.MockValSer):371 # Deleting the validator/serializer is necessary as otherwise they can get reused in372 # pydantic-core. Same applies for the core schema that can be reused in schema generation.373 delattr(cls, attr)374 375 cls.__pydantic_complete__ = False376 377 if _types_namespace is not None:378 rebuild_ns = _types_namespace379 elif _parent_namespace_depth > 0:380 rebuild_ns = _typing_extra.parent_frame_namespace(parent_depth=_parent_namespace_depth, force=True) or {}381 else:382 rebuild_ns = {}383 384 ns_resolver = _namespace_utils.NsResolver(385 parent_namespace=rebuild_ns,386 )387 388 return _pydantic_dataclasses.complete_dataclass(389 cls,390 _config.ConfigWrapper(cls.__pydantic_config__, check=False),391 raise_errors=raise_errors,392 ns_resolver=ns_resolver,393 # We could provide a different config instead (with `'defer_build'` set to `True`)394 # of this explicit `_force_build` argument, but because config can come from the395 # decorator parameter or the `__pydantic_config__` attribute, `complete_dataclass`396 # will overwrite `__pydantic_config__` with the provided config above:397 _force_build=True,398 )399 400 401def is_pydantic_dataclass(class_: type[Any], /) -> TypeGuard[type[PydanticDataclass]]:402 """Whether a class is a pydantic dataclass.403 404 Args:405 class_: The class.406 407 Returns:408 `True` if the class is a pydantic dataclass, `False` otherwise.409 """410 try:411 return '__is_pydantic_dataclass__' in class_.__dict__ and dataclasses.is_dataclass(class_)412 except AttributeError:413 return False414 