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- """Support for alias configurations."""
-
- from __future__ import annotations
-
- import dataclasses
- from typing import Any, Callable, Literal
-
- from pydantic_core import PydanticUndefined
-
- from ._internal import _internal_dataclass
-
- __all__ = ('AliasGenerator', 'AliasPath', 'AliasChoices')
-
-
- @dataclasses.dataclass(**_internal_dataclass.slots_true)
- class AliasPath:
- """!!! abstract "Usage Documentation"
- [`AliasPath` and `AliasChoices`](../concepts/alias.md#aliaspath-and-aliaschoices)
-
- A data class used by `validation_alias` as a convenience to create aliases.
-
- Attributes:
- path: A list of string or integer aliases.
- """
-
- path: list[int | str]
-
- def __init__(self, first_arg: str, *args: str | int) -> None:
- self.path = [first_arg] + list(args)
-
- def convert_to_aliases(self) -> list[str | int]:
- """Converts arguments to a list of string or integer aliases.
-
- Returns:
- The list of aliases.
- """
- return self.path
-
- def search_dict_for_path(self, d: dict) -> Any:
- """Searches a dictionary for the path specified by the alias.
-
- Returns:
- The value at the specified path, or `PydanticUndefined` if the path is not found.
- """
- v = d
- for k in self.path:
- if isinstance(v, str):
- # disallow indexing into a str, like for AliasPath('x', 0) and x='abc'
- return PydanticUndefined
- try:
- v = v[k]
- except (KeyError, IndexError, TypeError):
- return PydanticUndefined
- return v
-
-
- @dataclasses.dataclass(**_internal_dataclass.slots_true)
- class AliasChoices:
- """!!! abstract "Usage Documentation"
- [`AliasPath` and `AliasChoices`](../concepts/alias.md#aliaspath-and-aliaschoices)
-
- A data class used by `validation_alias` as a convenience to create aliases.
-
- Attributes:
- choices: A list containing a string or `AliasPath`.
- """
-
- choices: list[str | AliasPath]
-
- def __init__(self, first_choice: str | AliasPath, *choices: str | AliasPath) -> None:
- self.choices = [first_choice] + list(choices)
-
- def convert_to_aliases(self) -> list[list[str | int]]:
- """Converts arguments to a list of lists containing string or integer aliases.
-
- Returns:
- The list of aliases.
- """
- aliases: list[list[str | int]] = []
- for c in self.choices:
- if isinstance(c, AliasPath):
- aliases.append(c.convert_to_aliases())
- else:
- aliases.append([c])
- return aliases
-
-
- @dataclasses.dataclass(**_internal_dataclass.slots_true)
- class AliasGenerator:
- """!!! abstract "Usage Documentation"
- [Using an `AliasGenerator`](../concepts/alias.md#using-an-aliasgenerator)
-
- A data class used by `alias_generator` as a convenience to create various aliases.
-
- Attributes:
- alias: A callable that takes a field name and returns an alias for it.
- validation_alias: A callable that takes a field name and returns a validation alias for it.
- serialization_alias: A callable that takes a field name and returns a serialization alias for it.
- """
-
- alias: Callable[[str], str] | None = None
- validation_alias: Callable[[str], str | AliasPath | AliasChoices] | None = None
- serialization_alias: Callable[[str], str] | None = None
-
- def _generate_alias(
- self,
- alias_kind: Literal['alias', 'validation_alias', 'serialization_alias'],
- allowed_types: tuple[type[str] | type[AliasPath] | type[AliasChoices], ...],
- field_name: str,
- ) -> str | AliasPath | AliasChoices | None:
- """Generate an alias of the specified kind. Returns None if the alias generator is None.
-
- Raises:
- TypeError: If the alias generator produces an invalid type.
- """
- alias = None
- if alias_generator := getattr(self, alias_kind):
- alias = alias_generator(field_name)
- if alias and not isinstance(alias, allowed_types):
- raise TypeError(
- f'Invalid `{alias_kind}` type. `{alias_kind}` generator must produce one of `{allowed_types}`'
- )
- return alias
-
- def generate_aliases(self, field_name: str) -> tuple[str | None, str | AliasPath | AliasChoices | None, str | None]:
- """Generate `alias`, `validation_alias`, and `serialization_alias` for a field.
-
- Returns:
- A tuple of three aliases - validation, alias, and serialization.
- """
- alias = self._generate_alias('alias', (str,), field_name)
- validation_alias = self._generate_alias('validation_alias', (str, AliasChoices, AliasPath), field_name)
- serialization_alias = self._generate_alias('serialization_alias', (str,), field_name)
-
- return alias, validation_alias, serialization_alias # type: ignore
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